.forgejo/patches/ghc-9.8.patch

@@ -1,18 +0,0 @@
-Support ghc-9.8 by widening a lot of constraints.
-
-This patch can be removed once upstream supports ghc 9.8 offically.
-
-diff -uprN git-annex-10.20240227.orig/cabal.project git-annex-10.20240227/cabal.project
---- git-annex-10.20240227.orig/cabal.project	1970-01-01 01:00:00.000000000 +0100
-+++ git-annex-10.20240227/cabal.project	2024-04-28 13:30:14.061706299 +0200
-@@ -0,0 +1,10 @@
-+packages: *.cabal
-+
-+allow-newer: dav
-+allow-newer: haskeline:filepath
-+allow-newer: haskeline:directory
-+allow-newer: xml-hamlet
-+allow-newer: aws:filepath
-+allow-newer: dbus:network
-+allow-newer: dbus:filepath
-+allow-newer: microstache:filepath

.forgejo/workflows/generate-lockfile.yml

@@ -1,85 +0,0 @@
-on:
-  workflow_dispatch:
-    inputs:
-      ref_name:
-        description: 'Tag or commit'
-        required: true
-        type: string
-
-  push:
-    tags:
-      - '*'
-
-jobs:
-  cabal-config-edge:
-    name: Generate cabal config for edge
-    runs-on: x86_64
-    container:
-      image: alpine:edge
-    env:
-      CI_ALPINE_TARGET_RELEASE: edge
-    steps:
-      - name: Environment setup
-        run: apk add nodejs git cabal patch
-      - name: Repo pull
-        uses: actions/checkout@v4
-        with:
-          fetch-depth: 1
-          ref: ${{ inputs.ref_name }}
-      - name: Config generation
-        run: |
-          patch -p1 -i .forgejo/patches/ghc-9.8.patch
-          HOME="${{ github.workspace}}"/cabal_cache cabal update
-          HOME="${{ github.workspace}}"/cabal_cache cabal v2-freeze --shadow-installed-packages --strong-flags --flags="+assistant +webapp +pairing +production +torrentparser +magicmime +benchmark -debuglocks +dbus +networkbsd +gitlfs +httpclientrestricted"
-          mv cabal.project.freeze git-annex.config
-      - name: Package upload
-        uses: forgejo/upload-artifact@v3
-        with:
-          name: cabalconfigedge
-          path: git-annex*.config
-  cabal-config-v321:
-    name: Generate cabal config for v3.21
-    runs-on: x86_64
-    container:
-      image: alpine:3.21
-    env:
-      CI_ALPINE_TARGET_RELEASE: v3.21
-    steps:
-      - name: Environment setup
-        run: apk add nodejs git cabal patch
-      - name: Repo pull
-        uses: actions/checkout@v4
-        with:
-          fetch-depth: 1
-          ref: ${{ inputs.ref_name }}
-      - name: Config generation
-        run: |
-          patch -p1 -i .forgejo/patches/ghc-9.8.patch
-          HOME="${{ github.workspace }}"/cabal_cache cabal update
-          HOME="${{ github.workspace }}"/cabal_cache cabal v2-freeze --shadow-installed-packages --strong-flags --flags="+assistant +webapp +pairing +production +torrentparser +magicmime +benchmark -debuglocks +dbus +networkbsd +gitlfs +httpclientrestricted"
-          mv cabal.project.freeze git-annex.config
-      - name: Package upload
-        uses: forgejo/upload-artifact@v3
-        with:
-          name: cabalconfig321
-          path: git-annex*.config
-  upload-tarball:
-    name: Upload to generic repo
-    runs-on: x86_64
-    needs: [cabal-config-edge,cabal-config-v321]
-    container:
-      image: alpine:latest
-    steps:
-      - name: Environment setup
-        run: apk add nodejs curl findutils
-      - name: Package download
-        uses: forgejo/download-artifact@v3
-      - name: Package deployment 
-        run: |
-          if test $GITHUB_REF_NAME == "ci" ; then
-            CI_REF_NAME=${{ inputs.ref_name }}
-          else
-            CI_REF_NAME=$GITHUB_REF_NAME
-          fi
-          curl --user ${{ vars.CODE_FORGEJO_USER }}:${{ secrets.CODE_FORGEJO_TOKEN }} --upload-file ./cabalconfigedge/git-annex.config ${{ github.server_url }}/api/packages/mirrors/generic/git-annex/$CI_REF_NAME/git-annex-$CI_REF_NAME-edge.cabal
-          curl --user ${{ vars.CODE_FORGEJO_USER }}:${{ secrets.CODE_FORGEJO_TOKEN }} --upload-file ./cabalconfig321/git-annex.config ${{ github.server_url }}/api/packages/mirrors/generic/git-annex/$CI_REF_NAME/git-annex-$CI_REF_NAME-v321.cabal

.forgejo/workflows/mirror-repository.yml

@@ -1,50 +0,0 @@
-on:
-  workflow_dispatch:
-
-  schedule:
-    - cron: '@hourly'
-
-jobs:
-  mirror:
-    name: Pull from upstream
-    runs-on: x86_64
-    container:
-      image: alpine:latest
-    env:
-      upstream: https://git.joeyh.name/git/git-annex.git 
-      tags: '10.2025*'
-    steps:
-      - name: Environment setup
-        run: apk add grep git sed coreutils bash nodejs
-      - name: Fetch destination
-        uses: actions/checkout@v4
-        with:
-          fetch_depth: 1
-          ref: ci
-          token: ${{ secrets.CODE_FORGEJO_TOKEN }}
-      - name: Missing tag detecting
-        run: |
-          git ls-remote $upstream "refs/tags/$tags" | grep -v '{' | sed 's|.*/||' | sort > upstream_tags
-          git ls-remote ${{ github.server_url}}/${{ github.repository }} "refs/tags/$tags" | grep -v '{' | sed 's|.*/||' | sort > destination_tags
-          comm -23 upstream_tags destination_tags > missing_tags
-          echo "Missing tags:"
-          cat missing_tags
-      - name: Missing tag fetch
-        run: |
-          git remote add upstream $upstream
-          while read tag; do
-            git fetch upstream tag $tag --no-tags
-          done < missing_tags
-      - name: Packaging workflow injection
-        run: |
-          while read tag; do
-            git checkout $tag
-            git tag -d $tag
-            git checkout ci -- ./.forgejo
-            git config user.name "forgejo-actions[bot]"
-            git config user.email "dev@ayakael.net"
-            git commit -m 'Inject custom workflow'
-            git tag -a $tag -m $tag
-          done < missing_tags
-      - name: Push to destination
-        run: git push --force origin refs/tags/*:refs/tags/* --tags   

.ghci

@@ -0,0 +1 @@
+:load Common

.gitattributes

@@ -0,0 +1 @@
+debian/changelog merge=dpkg-mergechangelogs

.gitignore

@@ -0,0 +1,35 @@
+tags
+Setup
+*.hi
+*.o
+tmp
+test
+build-stamp
+Build/SysConfig.hs
+Build/InstallDesktopFile
+Build/EvilSplicer
+Build/Standalone
+Build/OSXMkLibs
+Build/LinuxMkLibs
+Build/BuildVersion
+git-annex
+git-annex.1
+git-annex-shell.1
+git-union-merge
+git-union-merge.1
+doc/.ikiwiki
+html
+*.tix
+.hpc
+dist
+# Sandboxed builds
+cabal-dev
+.cabal-sandbox
+cabal.sandbox.config
+cabal.config
+# Project-local emacs configuration
+.dir-locals.el
+# OSX related
+.DS_Store
+.virthualenv
+.tasty-rerun-log

.mailmap

@@ -0,0 +1,7 @@
+Joey Hess <id@joeyh.name> http://joey.kitenet.net/ <joey@web>
+Joey Hess <id@joeyh.name> http://joeyh.name/ <joey@web>
+Joey Hess <id@joeyh.name> http://joeyh.name/ <http://joeyh.name/@web>
+Yaroslav Halchenko <debian@onerussian.com>
+Yaroslav Halchenko <debian@onerussian.com> http://yarikoptic.myopenid.com/ <site-myopenid@web>
+Yaroslav Halchenko <debian@onerussian.com> https://www.google.com/accounts/o8/id?id=AItOawnx8kHW66N3BqmkVpgtXDlYMvr8TJ5VvfY <Yaroslav@web>
+Richard Hartmann <richih@debian.org> https://www.google.com/accounts/o8/id?id=AItOawl9sYlePmv1xK-VvjBdN-5doOa_Xw-jH4U <Richard@web>

Annex.hs

@@ -0,0 +1,312 @@
+{- git-annex monad
+ -
+ - Copyright 2010-2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP, GeneralizedNewtypeDeriving, PackageImports #-}
+
+module Annex (
+	Annex,
+	AnnexState(..),
+	new,
+	run,
+	eval,
+	getState,
+	changeState,
+	withState,
+	setFlag,
+	setField,
+	setOutput,
+	getFlag,
+	getField,
+	addCleanup,
+	gitRepo,
+	inRepo,
+	fromRepo,
+	calcRepo,
+	getGitConfig,
+	changeGitConfig,
+	changeGitRepo,
+	getRemoteGitConfig,
+	withCurrentState,
+	changeDirectory,
+) where
+
+import Common
+import qualified Git
+import qualified Git.Config
+import Annex.Direct.Fixup
+import Git.CatFile
+import Git.CheckAttr
+import Git.CheckIgnore
+import Git.SharedRepository
+import qualified Git.Hook
+import qualified Git.Queue
+import Types.Key
+import Types.Backend
+import Types.GitConfig
+import qualified Types.Remote
+import Types.Crypto
+import Types.BranchState
+import Types.TrustLevel
+import Types.Group
+import Types.Messages
+import Types.UUID
+import Types.FileMatcher
+import Types.NumCopies
+import Types.LockPool
+import Types.MetaData
+import Types.DesktopNotify
+import Types.CleanupActions
+#ifdef WITH_QUVI
+import Utility.Quvi (QuviVersion)
+#endif
+import Utility.InodeCache
+import Utility.Url
+
+import "mtl" Control.Monad.Reader
+import Control.Concurrent
+import qualified Data.Map as M
+import qualified Data.Set as S
+
+{- git-annex's monad is a ReaderT around an AnnexState stored in a MVar.
+ - The MVar is not exposed outside this module.
+ -
+ - Note that when an Annex action fails and the exception is caught,
+ - ny changes the action has made to the AnnexState are retained,
+ - due to the use of the MVar to store the state.
+ -}
+newtype Annex a = Annex { runAnnex :: ReaderT (MVar AnnexState) IO a }
+	deriving (
+		Monad,
+		MonadIO,
+		MonadReader (MVar AnnexState),
+		MonadCatch,
+		MonadThrow,
+		MonadMask,
+		Functor,
+		Applicative
+	)
+
+-- internal state storage
+data AnnexState = AnnexState
+	{ repo :: Git.Repo
+	, gitconfig :: GitConfig
+	, backends :: [BackendA Annex]
+	, remotes :: [Types.Remote.RemoteA Annex]
+	, remoteannexstate :: M.Map UUID AnnexState
+	, output :: MessageState
+	, force :: Bool
+	, fast :: Bool
+	, auto :: Bool
+	, daemon :: Bool
+	, branchstate :: BranchState
+	, repoqueue :: Maybe Git.Queue.Queue
+	, catfilehandles :: M.Map FilePath CatFileHandle
+	, checkattrhandle :: Maybe CheckAttrHandle
+	, checkignorehandle :: Maybe (Maybe CheckIgnoreHandle)
+	, forcebackend :: Maybe String
+	, globalnumcopies :: Maybe NumCopies
+	, forcenumcopies :: Maybe NumCopies
+	, limit :: ExpandableMatcher Annex
+	, uuidmap :: Maybe UUIDMap
+	, preferredcontentmap :: Maybe (FileMatcherMap Annex)
+	, requiredcontentmap :: Maybe (FileMatcherMap Annex)
+	, shared :: Maybe SharedRepository
+	, forcetrust :: TrustMap
+	, trustmap :: Maybe TrustMap
+	, groupmap :: Maybe GroupMap
+	, ciphers :: M.Map StorableCipher Cipher
+	, lockpool :: LockPool
+	, flags :: M.Map String Bool
+	, fields :: M.Map String String
+	, modmeta :: [ModMeta]
+	, cleanup :: M.Map CleanupAction (Annex ())
+	, sentinalstatus :: Maybe SentinalStatus
+	, useragent :: Maybe String
+	, errcounter :: Integer
+	, unusedkeys :: Maybe (S.Set Key)
+	, tempurls :: M.Map Key URLString
+#ifdef WITH_QUVI
+	, quviversion :: Maybe QuviVersion
+#endif
+	, existinghooks :: M.Map Git.Hook.Hook Bool
+	, desktopnotify :: DesktopNotify
+	}
+
+newState :: GitConfig -> Git.Repo -> AnnexState
+newState c r = AnnexState
+	{ repo = r
+	, gitconfig = c
+	, backends = []
+	, remotes = []
+	, remoteannexstate = M.empty
+	, output = defaultMessageState
+	, force = False
+	, fast = False
+	, auto = False
+	, daemon = False
+	, branchstate = startBranchState
+	, repoqueue = Nothing
+	, catfilehandles = M.empty
+	, checkattrhandle = Nothing
+	, checkignorehandle = Nothing
+	, forcebackend = Nothing
+	, globalnumcopies = Nothing
+	, forcenumcopies = Nothing
+	, limit = BuildingMatcher []
+	, uuidmap = Nothing
+	, preferredcontentmap = Nothing
+	, requiredcontentmap = Nothing
+	, shared = Nothing
+	, forcetrust = M.empty
+	, trustmap = Nothing
+	, groupmap = Nothing
+	, ciphers = M.empty
+	, lockpool = M.empty
+	, flags = M.empty
+	, fields = M.empty
+	, modmeta = []
+	, cleanup = M.empty
+	, sentinalstatus = Nothing
+	, useragent = Nothing
+	, errcounter = 0
+	, unusedkeys = Nothing
+	, tempurls = M.empty
+#ifdef WITH_QUVI
+	, quviversion = Nothing
+#endif
+	, existinghooks = M.empty
+	, desktopnotify = mempty
+	}
+
+{- Makes an Annex state object for the specified git repo.
+ - Ensures the config is read, if it was not already. -}
+new :: Git.Repo -> IO AnnexState
+new r = do
+	r' <- Git.Config.read =<< Git.relPath r
+	let c = extractGitConfig r'
+	newState c <$> if annexDirect c then fixupDirect r' else return r'
+
+{- Performs an action in the Annex monad from a starting state,
+ - returning a new state. -}
+run :: AnnexState -> Annex a -> IO (a, AnnexState)
+run s a = do
+	mvar <- newMVar s
+	r <- runReaderT (runAnnex a) mvar
+	s' <- takeMVar mvar
+	return (r, s')
+
+{- Performs an action in the Annex monad from a starting state, 
+ - and throws away the new state. -}
+eval :: AnnexState -> Annex a -> IO a
+eval s a = do
+	mvar <- newMVar s
+	runReaderT (runAnnex a) mvar
+
+getState :: (AnnexState -> v) -> Annex v
+getState selector = do
+	mvar <- ask
+	s <- liftIO $ readMVar mvar
+	return $ selector s
+
+changeState :: (AnnexState -> AnnexState) -> Annex ()
+changeState modifier = do
+	mvar <- ask
+	liftIO $ modifyMVar_ mvar $ return . modifier
+
+withState :: (AnnexState -> (AnnexState, b)) -> Annex b
+withState modifier = do
+	mvar <- ask
+	liftIO $ modifyMVar mvar $ return . modifier
+
+{- Sets a flag to True -}
+setFlag :: String -> Annex ()
+setFlag flag = changeState $ \s ->
+	s { flags = M.insertWith' const flag True $ flags s }
+
+{- Sets a field to a value -}
+setField :: String -> String -> Annex ()
+setField field value = changeState $ \s ->
+	s { fields = M.insertWith' const field value $ fields s }
+
+{- Adds a cleanup action to perform. -}
+addCleanup :: CleanupAction -> Annex () -> Annex ()
+addCleanup k a = changeState $ \s ->
+	s { cleanup = M.insertWith' const k a $ cleanup s }
+
+{- Sets the type of output to emit. -}
+setOutput :: OutputType -> Annex ()
+setOutput o = changeState $ \s ->
+	s { output = (output s) { outputType = o } }
+
+{- Checks if a flag was set. -}
+getFlag :: String -> Annex Bool
+getFlag flag = fromMaybe False . M.lookup flag <$> getState flags
+
+{- Gets the value of a field. -}
+getField :: String -> Annex (Maybe String)
+getField field = M.lookup field <$> getState fields
+
+{- Returns the annex's git repository. -}
+gitRepo :: Annex Git.Repo
+gitRepo = getState repo
+
+{- Runs an IO action in the annex's git repository. -}
+inRepo :: (Git.Repo -> IO a) -> Annex a
+inRepo a = liftIO . a =<< gitRepo
+
+{- Extracts a value from the annex's git repisitory. -}
+fromRepo :: (Git.Repo -> a) -> Annex a
+fromRepo a = a <$> gitRepo
+
+{- Calculates a value from an annex's git repository and its GitConfig. -}
+calcRepo :: (Git.Repo -> GitConfig -> IO a) -> Annex a
+calcRepo a = do
+	s <- getState id
+	liftIO $ a (repo s) (gitconfig s)
+
+{- Gets the GitConfig settings. -}
+getGitConfig :: Annex GitConfig
+getGitConfig = getState gitconfig
+
+{- Modifies a GitConfig setting. -}
+changeGitConfig :: (GitConfig -> GitConfig) -> Annex ()
+changeGitConfig a = changeState $ \s -> s { gitconfig = a (gitconfig s) }
+
+{- Changing the git Repo data also involves re-extracting its GitConfig. -}
+changeGitRepo :: Git.Repo -> Annex ()
+changeGitRepo r = changeState $ \s -> s
+	{ repo = r
+	, gitconfig = extractGitConfig r
+	}
+
+{- Gets the RemoteGitConfig from a remote, given the Git.Repo for that
+ - remote. -}
+getRemoteGitConfig :: Git.Repo -> Annex RemoteGitConfig
+getRemoteGitConfig r = do
+	g <- gitRepo
+	return $ extractRemoteGitConfig g (Git.repoDescribe r)
+
+{- Converts an Annex action into an IO action, that runs with a copy
+ - of the current Annex state. 
+ -
+ - Use with caution; the action should not rely on changing the
+ - state, as it will be thrown away. -}
+withCurrentState :: Annex a -> Annex (IO a)
+withCurrentState a = do
+	s <- getState id
+	return $ eval s a
+
+{- It's not safe to use setCurrentDirectory in the Annex monad,
+ - because the git repo paths are stored relative.
+ - Instead, use this.
+ -}
+changeDirectory :: FilePath -> Annex ()
+changeDirectory d = do
+	r <- liftIO . Git.adjustPath absPath =<< gitRepo
+	liftIO $ setCurrentDirectory d
+	r' <- liftIO $ Git.relPath r
+	changeState $ \s -> s { repo = r' }

Annex/AutoMerge.hs

@@ -0,0 +1,206 @@
+{- git-annex automatic merge conflict resolution
+ -
+ - Copyright 2012-2014 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.AutoMerge
+	( autoMergeFrom
+	, resolveMerge
+	, commitResolvedMerge
+	) where
+
+import Common.Annex
+import qualified Annex.Queue
+import Annex.Direct
+import Annex.CatFile
+import Annex.Link
+import qualified Git.LsFiles as LsFiles
+import qualified Git.UpdateIndex as UpdateIndex
+import qualified Git.Merge
+import qualified Git.Ref
+import qualified Git
+import qualified Git.Branch
+import Git.Types (BlobType(..))
+import Config
+import Annex.ReplaceFile
+import Git.FileMode
+import Annex.VariantFile
+
+import qualified Data.Set as S
+
+{- Merges from a branch into the current branch
+ - (which may not exist yet),
+ - with automatic merge conflict resolution.
+ -
+ - Callers should use Git.Branch.changed first, to make sure that
+ - there are changed from the current branch to the branch being merged in.
+ -}
+autoMergeFrom :: Git.Ref -> (Maybe Git.Ref) -> Git.Branch.CommitMode -> Annex Bool
+autoMergeFrom branch currbranch commitmode = do
+	showOutput
+	case currbranch of
+		Nothing -> go Nothing
+		Just b -> go =<< inRepo (Git.Ref.sha b)
+  where
+	go old = ifM isDirect
+		( mergeDirect currbranch old branch (resolveMerge old branch) commitmode
+		, inRepo (Git.Merge.mergeNonInteractive branch commitmode)
+			<||> (resolveMerge old branch <&&> commitResolvedMerge commitmode)
+		)
+
+{- Resolves a conflicted merge. It's important that any conflicts be
+ - resolved in a way that itself avoids later merge conflicts, since
+ - multiple repositories may be doing this concurrently.
+ -
+ - Only merge conflicts where at least one side is an annexed file
+ - is resolved.
+ -
+ - This uses the Keys pointed to by the files to construct new
+ - filenames. So when both sides modified annexed file foo, 
+ - it will be deleted, and replaced with files foo.variant-A and
+ - foo.variant-B.
+ -
+ - On the other hand, when one side deleted foo, and the other modified it,
+ - it will be deleted, and the modified version stored as file
+ - foo.variant-A (or B).
+ -
+ - It's also possible that one side has foo as an annexed file, and
+ - the other as a directory or non-annexed file. The annexed file
+ - is renamed to resolve the merge, and the other object is preserved as-is.
+ -
+ - In indirect mode, the merge is resolved in the work tree and files
+ - staged, to clean up from a conflicted merge that was run in the work
+ - tree.
+ -
+ - In direct mode, the work tree is not touched here; files are staged to
+ - the index, and written to the gitAnnexMergeDir, for later handling by
+ - the direct mode merge code.
+ -}
+resolveMerge :: Maybe Git.Ref -> Git.Ref -> Annex Bool
+resolveMerge us them = do
+	top <- fromRepo Git.repoPath
+	(fs, cleanup) <- inRepo (LsFiles.unmerged [top])
+	mergedfs <- catMaybes <$> mapM (resolveMerge' us them) fs
+	let merged = not (null mergedfs)
+	void $ liftIO cleanup
+
+	unlessM isDirect $ do
+		(deleted, cleanup2) <- inRepo (LsFiles.deleted [top])
+		unless (null deleted) $
+			Annex.Queue.addCommand "rm" [Params "--quiet -f --"] deleted
+		void $ liftIO cleanup2
+
+	when merged $ do
+		unlessM isDirect $
+			cleanConflictCruft mergedfs top
+		Annex.Queue.flush
+		showLongNote "Merge conflict was automatically resolved; you may want to examine the result."
+	return merged
+
+resolveMerge' :: Maybe Git.Ref -> Git.Ref -> LsFiles.Unmerged -> Annex (Maybe FilePath)
+resolveMerge' Nothing _ _ = return Nothing
+resolveMerge' (Just us) them u = do
+	kus <- getkey LsFiles.valUs LsFiles.valUs 
+	kthem <- getkey LsFiles.valThem LsFiles.valThem
+	case (kus, kthem) of
+		-- Both sides of conflict are annexed files
+		(Just keyUs, Just keyThem)
+			| keyUs /= keyThem -> resolveby $ do
+				makelink keyUs
+				makelink keyThem
+			| otherwise -> resolveby $
+				makelink keyUs
+		-- Our side is annexed file, other side is not.
+		(Just keyUs, Nothing) -> resolveby $ do
+			graftin them file LsFiles.valThem LsFiles.valThem
+			makelink keyUs
+		-- Our side is not annexed file, other side is.
+		(Nothing, Just keyThem) -> resolveby $ do
+			graftin us file LsFiles.valUs LsFiles.valUs
+			makelink keyThem
+		-- Neither side is annexed file; cannot resolve.
+		(Nothing, Nothing) -> return Nothing
+  where
+	file = LsFiles.unmergedFile u
+
+	getkey select select'
+		| select (LsFiles.unmergedBlobType u) == Just SymlinkBlob =
+			case select' (LsFiles.unmergedSha u) of
+				Nothing -> return Nothing
+				Just sha -> catKey sha symLinkMode
+		| otherwise = return Nothing
+	
+	makelink key = do
+		let dest = variantFile file key
+		l <- calcRepo $ gitAnnexLink dest key
+		replacewithlink dest l
+		stageSymlink dest =<< hashSymlink l
+
+	replacewithlink dest link = ifM isDirect
+		( do
+			d <- fromRepo gitAnnexMergeDir
+			replaceFile (d </> dest) $ makeGitLink link
+		, replaceFile dest $ makeGitLink link
+		)
+
+	{- Stage a graft of a directory or file from a branch.
+	 -
+	 - When there is a conflicted merge where one side is a directory
+	 - or file, and the other side is a symlink, git merge always
+	 - updates the work tree to contain the non-symlink. So, the
+	 - directory or file will already be in the work tree correctly,
+	 - and they just need to be staged into place. Do so by copying the
+	 - index. (Note that this is also better than calling git-add
+	 - because on a crippled filesystem, it preserves any symlink
+	 - bits.)
+	 -
+	 - It's also possible for the branch to have a symlink in it,
+	 - which is not a git-annex symlink. In this special case,
+	 - git merge does not update the work tree to contain the symlink
+	 - from the branch, so we have to do so manually.
+	 -}
+	graftin b item select select' = do
+		Annex.Queue.addUpdateIndex
+			=<< fromRepo (UpdateIndex.lsSubTree b item)
+		when (select (LsFiles.unmergedBlobType u) == Just SymlinkBlob) $
+			case select' (LsFiles.unmergedSha u) of
+				Nothing -> noop
+				Just sha -> do
+					link <- catLink True sha
+					replacewithlink item link
+		
+	resolveby a = do
+		{- Remove conflicted file from index so merge can be resolved. -}
+		Annex.Queue.addCommand "rm" [Params "--quiet -f --cached --"] [file]
+		void a
+		return (Just file)
+
+{- git-merge moves conflicting files away to files
+ - named something like f~HEAD or f~branch or just f, but the
+ - exact name chosen can vary. Once the conflict is resolved,
+ - this cruft can be deleted. To avoid deleting legitimate
+ - files that look like this, only delete files that are
+ - A) not staged in git and B) look like git-annex symlinks.
+ -}
+cleanConflictCruft :: [FilePath] -> FilePath -> Annex ()
+cleanConflictCruft resolvedfs top = do
+	(fs, cleanup) <- inRepo $ LsFiles.notInRepo False [top]
+	mapM_ clean fs
+	void $ liftIO cleanup
+  where
+	clean f
+		| matchesresolved f = whenM (isJust <$> isAnnexLink f) $
+			liftIO $ nukeFile f
+		| otherwise = noop
+	s = S.fromList resolvedfs
+	matchesresolved f = S.member f s || S.member (base f) s
+	base f = reverse $ drop 1 $ dropWhile (/= '~') $ reverse f
+	
+commitResolvedMerge :: Git.Branch.CommitMode -> Annex Bool
+commitResolvedMerge commitmode = inRepo $ Git.Branch.commitCommand commitmode
+	[ Param "--no-verify"
+	, Param "-m"
+	, Param "git-annex automatic merge conflict fix"
+	]

Annex/Branch.hs

@@ -0,0 +1,559 @@
+{- management of the git-annex branch
+ -
+ - Copyright 2011-2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.Branch (
+	fullname,
+	name,
+	hasOrigin,
+	hasSibling,
+	siblingBranches,
+	create,
+	update,
+	forceUpdate,
+	updateTo,
+	get,
+	getHistorical,
+	change,
+	commit,
+	forceCommit,
+	files,
+	withIndex,
+	performTransitions,
+) where
+
+import qualified Data.ByteString.Lazy as L
+import qualified Data.Set as S
+import qualified Data.Map as M
+import Data.Bits.Utils
+import Control.Concurrent (threadDelay)
+
+import Common.Annex
+import Annex.BranchState
+import Annex.Journal
+import Annex.Index
+import qualified Git
+import qualified Git.Command
+import qualified Git.Ref
+import qualified Git.Sha
+import qualified Git.Branch
+import qualified Git.UnionMerge
+import qualified Git.UpdateIndex
+import Git.HashObject
+import Git.Types
+import Git.FilePath
+import Annex.CatFile
+import Annex.Perms
+import Logs
+import Logs.Transitions
+import Logs.Trust.Pure
+import Logs.Difference.Pure
+import Annex.ReplaceFile
+import qualified Annex.Queue
+import Annex.Branch.Transitions
+import qualified Annex
+
+{- Name of the branch that is used to store git-annex's information. -}
+name :: Git.Ref
+name = Git.Ref "git-annex"
+
+{- Fully qualified name of the branch. -}
+fullname :: Git.Ref
+fullname = Git.Ref $ "refs/heads/" ++ fromRef name
+
+{- Branch's name in origin. -}
+originname :: Git.Ref
+originname = Git.Ref $ "origin/" ++ fromRef name
+
+{- Does origin/git-annex exist? -}
+hasOrigin :: Annex Bool
+hasOrigin = inRepo $ Git.Ref.exists originname
+
+{- Does the git-annex branch or a sibling foo/git-annex branch exist? -}
+hasSibling :: Annex Bool
+hasSibling = not . null <$> siblingBranches
+
+{- List of git-annex (refs, branches), including the main one and any
+ - from remotes. Duplicate refs are filtered out. -}
+siblingBranches :: Annex [(Git.Ref, Git.Branch)]
+siblingBranches = inRepo $ Git.Ref.matchingUniq [name]
+
+{- Creates the branch, if it does not already exist. -}
+create :: Annex ()
+create = void getBranch
+
+{- Returns the ref of the branch, creating it first if necessary. -}
+getBranch :: Annex Git.Ref
+getBranch = maybe (hasOrigin >>= go >>= use) return =<< branchsha
+  where
+	go True = do
+		inRepo $ Git.Command.run
+			[Param "branch", Param $ fromRef name, Param $ fromRef originname]
+		fromMaybe (error $ "failed to create " ++ fromRef name)
+			<$> branchsha
+	go False = withIndex' True $
+		inRepo $ Git.Branch.commitAlways Git.Branch.AutomaticCommit "branch created" fullname []
+	use sha = do
+		setIndexSha sha
+		return sha
+	branchsha = inRepo $ Git.Ref.sha fullname
+
+{- Ensures that the branch and index are up-to-date; should be
+ - called before data is read from it. Runs only once per git-annex run. -}
+update :: Annex ()
+update = runUpdateOnce $ void $ updateTo =<< siblingBranches
+
+{- Forces an update even if one has already been run. -}
+forceUpdate :: Annex Bool
+forceUpdate = updateTo =<< siblingBranches
+
+{- Merges the specified Refs into the index, if they have any changes not
+ - already in it. The Branch names are only used in the commit message;
+ - it's even possible that the provided Branches have not been updated to
+ - point to the Refs yet.
+ - 
+ - The branch is fast-forwarded if possible, otherwise a merge commit is
+ - made.
+ -
+ - Before Refs are merged into the index, it's important to first stage the
+ - journal into the index. Otherwise, any changes in the journal would
+ - later get staged, and might overwrite changes made during the merge.
+ - This is only done if some of the Refs do need to be merged.
+ -
+ - Also handles performing any Transitions that have not yet been
+ - performed, in either the local branch, or the Refs.
+ -
+ - Returns True if any refs were merged in, False otherwise.
+ -}
+updateTo :: [(Git.Ref, Git.Branch)] -> Annex Bool
+updateTo pairs = do
+	-- ensure branch exists, and get its current ref
+	branchref <- getBranch
+	dirty <- journalDirty
+	ignoredrefs <- getIgnoredRefs
+	(refs, branches) <- unzip <$> filterM (isnewer ignoredrefs) pairs
+	if null refs
+		{- Even when no refs need to be merged, the index
+		 - may still be updated if the branch has gotten ahead 
+		 - of the index. -}
+		then whenM (needUpdateIndex branchref) $ lockJournal $ \jl -> do
+			forceUpdateIndex jl branchref
+			{- When there are journalled changes
+			 - as well as the branch being updated,
+			 - a commit needs to be done. -}
+			when dirty $
+				go branchref True [] [] jl
+		else lockJournal $ go branchref dirty refs branches
+	return $ not $ null refs
+  where
+	isnewer ignoredrefs (r, _)
+		| S.member r ignoredrefs = return False
+		| otherwise = inRepo $ Git.Branch.changed fullname r
+	go branchref dirty refs branches jl = withIndex $ do
+		cleanjournal <- if dirty then stageJournal jl else return noop
+		let merge_desc = if null branches
+			then "update"
+			else "merging " ++
+				unwords (map Git.Ref.describe branches) ++ 
+				" into " ++ fromRef name
+		localtransitions <- parseTransitionsStrictly "local"
+			<$> getLocal transitionsLog
+		unless (null branches) $ do
+			showSideAction merge_desc
+			mapM_ checkBranchDifferences refs
+			mergeIndex jl refs
+		let commitrefs = nub $ fullname:refs
+		unlessM (handleTransitions jl localtransitions commitrefs) $ do
+			ff <- if dirty
+				then return False
+				else inRepo $ Git.Branch.fastForward fullname refs
+			if ff
+				then updateIndex jl branchref
+				else commitIndex jl branchref merge_desc commitrefs
+		liftIO cleanjournal
+
+{- Gets the content of a file, which may be in the journal, or in the index
+ - (and committed to the branch).
+ - 
+ - Updates the branch if necessary, to ensure the most up-to-date available
+ - content is returned.
+ -
+ - Returns an empty string if the file doesn't exist yet. -}
+get :: FilePath -> Annex String
+get file = do
+	update
+	getLocal file
+
+{- Like get, but does not merge the branch, so the info returned may not
+ - reflect changes in remotes.
+ - (Changing the value this returns, and then merging is always the
+ - same as using get, and then changing its value.) -}
+getLocal :: FilePath -> Annex String
+getLocal file = go =<< getJournalFileStale file
+  where
+	go (Just journalcontent) = return journalcontent
+	go Nothing = getRaw file
+
+getRaw :: FilePath -> Annex String
+getRaw = getRef fullname
+
+getHistorical :: RefDate -> FilePath -> Annex String
+getHistorical date = getRef (Git.Ref.dateRef fullname date)
+
+getRef :: Ref -> FilePath -> Annex String
+getRef ref file = withIndex $ decodeBS <$> catFile ref file
+
+{- Applies a function to modifiy the content of a file.
+ -
+ - Note that this does not cause the branch to be merged, it only
+ - modifes the current content of the file on the branch.
+ -}
+change :: FilePath -> (String -> String) -> Annex ()
+change file a = lockJournal $ \jl -> a <$> getLocal file >>= set jl file
+
+{- Records new content of a file into the journal -}
+set :: JournalLocked -> FilePath -> String -> Annex ()
+set = setJournalFile
+
+{- Stages the journal, and commits staged changes to the branch. -}
+commit :: String -> Annex ()
+commit = whenM journalDirty . forceCommit
+
+{- Commits the current index to the branch even without any journalled
+ - changes. -}
+forceCommit :: String -> Annex ()
+forceCommit message = lockJournal $ \jl -> do
+	cleanjournal <- stageJournal jl
+	ref <- getBranch
+	withIndex $ commitIndex jl ref message [fullname]
+	liftIO cleanjournal
+
+{- Commits the staged changes in the index to the branch.
+ - 
+ - Ensures that the branch's index file is first updated to merge the state
+ - of the branch at branchref, before running the commit action. This
+ - is needed because the branch may have had changes pushed to it, that
+ - are not yet reflected in the index.
+ - 
+ - The branchref value can have been obtained using getBranch at any
+ - previous point, though getting it a long time ago makes the race
+ - more likely to occur.
+ -
+ - Note that changes may be pushed to the branch at any point in time!
+ - So, there's a race. If the commit is made using the newly pushed tip of
+ - the branch as its parent, and that ref has not yet been merged into the
+ - index, then the result is that the commit will revert the pushed
+ - changes, since they have not been merged into the index. This race
+ - is detected and another commit made to fix it.
+ -
+ - (It's also possible for the branch to be overwritten,
+ - losing the commit made here. But that's ok; the data is still in the
+ - index and will get committed again later.)
+ -}
+commitIndex :: JournalLocked -> Git.Ref -> String -> [Git.Ref] -> Annex ()
+commitIndex jl branchref message parents = do
+	showStoringStateAction
+	commitIndex' jl branchref message message 0 parents
+commitIndex' :: JournalLocked -> Git.Ref -> String -> String -> Integer -> [Git.Ref] -> Annex ()
+commitIndex' jl branchref message basemessage retrynum parents = do
+	updateIndex jl branchref
+	committedref <- inRepo $ Git.Branch.commitAlways Git.Branch.AutomaticCommit message fullname parents
+	setIndexSha committedref
+	parentrefs <- commitparents <$> catObject committedref
+	when (racedetected branchref parentrefs) $
+		fixrace committedref parentrefs
+  where
+	-- look for "parent ref" lines and return the refs
+	commitparents = map (Git.Ref . snd) . filter isparent .
+		map (toassoc . decodeBS) . L.split newline
+	newline = c2w8 '\n'
+	toassoc = separate (== ' ')
+	isparent (k,_) = k == "parent"
+		
+	{- The race can be detected by checking the commit's
+	 - parent, which will be the newly pushed branch,
+	 - instead of the expected ref that the index was updated to. -}
+	racedetected expectedref parentrefs
+		| expectedref `elem` parentrefs = False -- good parent
+		| otherwise = True -- race!
+		
+	{- To recover from the race, union merge the lost refs
+	 - into the index. -}
+	fixrace committedref lostrefs = do
+		showSideAction "recovering from race"
+		let retrynum' = retrynum+1
+		-- small sleep to let any activity that caused
+		-- the race settle down
+		liftIO $ threadDelay (100000 + fromInteger retrynum')
+		mergeIndex jl lostrefs
+		let racemessage = basemessage ++ " (recovery from race #" ++ show retrynum' ++ "; expected commit parent " ++ show branchref ++ " but found " ++ show lostrefs ++ " )"
+		commitIndex' jl committedref racemessage basemessage retrynum' [committedref]
+
+{- Lists all files on the branch. There may be duplicates in the list. -}
+files :: Annex [FilePath]
+files = do
+	update
+	(++)
+		<$> branchFiles
+		<*> getJournalledFilesStale
+
+{- Files in the branch, not including any from journalled changes,
+ - and without updating the branch. -}
+branchFiles :: Annex [FilePath]
+branchFiles = withIndex $ inRepo $ Git.Command.pipeNullSplitZombie
+	[ Params "ls-tree --name-only -r -z"
+	, Param $ fromRef fullname
+	]
+
+{- Populates the branch's index file with the current branch contents.
+ - 
+ - This is only done when the index doesn't yet exist, and the index 
+ - is used to build up changes to be commited to the branch, and merge
+ - in changes from other branches.
+ -}
+genIndex :: Git.Repo -> IO ()
+genIndex g = Git.UpdateIndex.streamUpdateIndex g
+	[Git.UpdateIndex.lsTree fullname g]
+
+{- Merges the specified refs into the index.
+ - Any changes staged in the index will be preserved. -}
+mergeIndex :: JournalLocked -> [Git.Ref] -> Annex ()
+mergeIndex jl branches = do
+	prepareModifyIndex jl
+	h <- catFileHandle
+	inRepo $ \g -> Git.UnionMerge.mergeIndex h g branches
+
+{- Removes any stale git lock file, to avoid git falling over when
+ - updating the index.
+ -
+ - Since all modifications of the index are performed inside this module,
+ - and only when the journal is locked, the fact that the journal has to be
+ - locked when this is called ensures that no other process is currently
+ - modifying the index. So any index.lock file must be stale, caused
+ - by git running when the system crashed, or the repository's disk was
+ - removed, etc.
+ -}
+prepareModifyIndex :: JournalLocked -> Annex ()
+prepareModifyIndex _jl = do
+	index <- fromRepo gitAnnexIndex
+	void $ liftIO $ tryIO $ removeFile $ index ++ ".lock"
+
+{- Runs an action using the branch's index file. -}
+withIndex :: Annex a -> Annex a
+withIndex = withIndex' False
+withIndex' :: Bool -> Annex a -> Annex a
+withIndex' bootstrapping a = do
+	f <- liftIO . absPath =<< fromRepo gitAnnexIndex
+	withIndexFile f $ do
+		checkIndexOnce $ unlessM (liftIO $ doesFileExist f) $ do
+			unless bootstrapping create
+			createAnnexDirectory $ takeDirectory f
+			unless bootstrapping $ inRepo genIndex
+		a
+
+{- Updates the branch's index to reflect the current contents of the branch.
+ - Any changes staged in the index will be preserved.
+ -
+ - Compares the ref stored in the lock file with the current
+ - ref of the branch to see if an update is needed.
+ -}
+updateIndex :: JournalLocked -> Git.Ref -> Annex ()
+updateIndex jl branchref = whenM (needUpdateIndex branchref) $
+	forceUpdateIndex jl branchref
+
+forceUpdateIndex :: JournalLocked -> Git.Ref -> Annex ()
+forceUpdateIndex jl branchref = do
+	withIndex $ mergeIndex jl [fullname]
+	setIndexSha branchref
+
+{- Checks if the index needs to be updated. -}
+needUpdateIndex :: Git.Ref -> Annex Bool
+needUpdateIndex branchref = do
+	f <- fromRepo gitAnnexIndexStatus
+	committedref <- Git.Ref . firstLine <$>
+		liftIO (catchDefaultIO "" $ readFileStrict f)
+	return (committedref /= branchref)
+
+{- Record that the branch's index has been updated to correspond to a
+ - given ref of the branch. -}
+setIndexSha :: Git.Ref -> Annex ()
+setIndexSha ref = do
+	f <- fromRepo gitAnnexIndexStatus
+	liftIO $ writeFile f $ fromRef ref ++ "\n"
+	setAnnexFilePerm f
+
+{- Stages the journal into the index and returns an action that will
+ - clean up the staged journal files, which should only be run once
+ - the index has been committed to the branch.
+ -
+ - Before staging, this removes any existing git index file lock.
+ - This is safe to do because stageJournal is the only thing that
+ - modifies this index file, and only one can run at a time, because
+ - the journal is locked. So any existing git index file lock must be
+ - stale, and the journal must contain any data that was in the process
+ - of being written to the index file when it crashed.
+ -}
+stageJournal :: JournalLocked -> Annex (IO ())
+stageJournal jl = withIndex $ do
+	prepareModifyIndex jl
+	g <- gitRepo
+	let dir = gitAnnexJournalDir g
+	(jlogf, jlogh) <- openjlog
+	withJournalHandle $ \jh -> do
+		h <- hashObjectStart g
+		Git.UpdateIndex.streamUpdateIndex g
+			[genstream dir h jh jlogh]
+		hashObjectStop h
+	return $ cleanup dir jlogh jlogf
+  where
+	genstream dir h jh jlogh streamer = do
+		v <- readDirectory jh
+		case v of
+			Nothing -> return ()
+			Just file -> do
+				unless (dirCruft file) $ do
+					let path = dir </> file
+					sha <- hashFile h path
+					hPutStrLn jlogh file
+					streamer $ Git.UpdateIndex.updateIndexLine
+						sha FileBlob (asTopFilePath $ fileJournal file)
+				genstream dir h jh jlogh streamer
+	-- Clean up the staged files, as listed in the temp log file.
+	-- The temp file is used to avoid needing to buffer all the
+	-- filenames in memory.
+	cleanup dir jlogh jlogf = do
+		hFlush jlogh
+		hSeek jlogh AbsoluteSeek 0
+		stagedfs <- lines <$> hGetContents jlogh
+		mapM_ (removeFile . (dir </>)) stagedfs
+		hClose jlogh
+		nukeFile jlogf
+	openjlog = do
+		tmpdir <- fromRepo gitAnnexTmpMiscDir
+		createAnnexDirectory tmpdir
+		liftIO $ openTempFile tmpdir "jlog"
+
+{- This is run after the refs have been merged into the index,
+ - but before the result is committed to the branch.
+ - (Which is why it's passed the contents of the local branches's
+ - transition log before that merge took place.)
+ -
+ - When the refs contain transitions that have not yet been done locally,
+ - the transitions are performed on the index, and a new branch
+ - is created from the result.
+ -
+ - When there are transitions recorded locally that have not been done
+ - to the remote refs, the transitions are performed in the index,
+ - and committed to the existing branch. In this case, the untransitioned
+ - remote refs cannot be merged into the branch (since transitions
+ - throw away history), so they are added to the list of refs to ignore,
+ - to avoid re-merging content from them again.
+ -}
+handleTransitions :: JournalLocked -> Transitions -> [Git.Ref] -> Annex Bool
+handleTransitions jl localts refs = do
+	m <- M.fromList <$> mapM getreftransition refs
+	let remotets = M.elems m
+	if all (localts ==) remotets
+		then return False
+		else do
+			let allts = combineTransitions (localts:remotets)
+			let (transitionedrefs, untransitionedrefs) =
+				partition (\r -> M.lookup r m == Just allts) refs
+			performTransitionsLocked jl allts (localts /= allts) transitionedrefs
+			ignoreRefs untransitionedrefs
+			return True
+  where
+	getreftransition ref = do
+		ts <- parseTransitionsStrictly "remote" . decodeBS
+			<$> catFile ref transitionsLog
+		return (ref, ts)
+
+ignoreRefs :: [Git.Ref] -> Annex ()
+ignoreRefs rs = do
+	old <- getIgnoredRefs
+	let s = S.unions [old, S.fromList rs]
+	f <- fromRepo gitAnnexIgnoredRefs
+	replaceFile f $ \tmp -> liftIO $ writeFile tmp $
+		unlines $ map fromRef $ S.elems s
+
+getIgnoredRefs :: Annex (S.Set Git.Ref)
+getIgnoredRefs = S.fromList . mapMaybe Git.Sha.extractSha . lines <$> content
+  where
+	content = do
+		f <- fromRepo gitAnnexIgnoredRefs
+		liftIO $ catchDefaultIO "" $ readFile f
+
+{- Performs the specified transitions on the contents of the index file,
+ - commits it to the branch, or creates a new branch.
+ -}
+performTransitions :: Transitions -> Bool -> [Ref] -> Annex ()
+performTransitions ts neednewlocalbranch transitionedrefs = lockJournal $ \jl ->
+	performTransitionsLocked jl ts neednewlocalbranch transitionedrefs
+performTransitionsLocked :: JournalLocked -> Transitions -> Bool -> [Ref] -> Annex ()
+performTransitionsLocked jl ts neednewlocalbranch transitionedrefs = do
+	-- For simplicity & speed, we're going to use the Annex.Queue to
+	-- update the git-annex branch, while it usually holds changes
+	-- for the head branch. Flush any such changes.
+	Annex.Queue.flush
+	withIndex $ do
+		prepareModifyIndex jl
+		run $ mapMaybe getTransitionCalculator $ transitionList ts
+		Annex.Queue.flush
+		if neednewlocalbranch
+			then do
+				committedref <- inRepo $ Git.Branch.commitAlways Git.Branch.AutomaticCommit message fullname transitionedrefs
+				setIndexSha committedref
+			else do
+				ref <- getBranch
+				commitIndex jl ref message (nub $ fullname:transitionedrefs)
+  where
+	message
+		| neednewlocalbranch && null transitionedrefs = "new branch for transition " ++ tdesc
+		| otherwise = "continuing transition " ++ tdesc
+	tdesc = show $ map describeTransition $ transitionList ts
+
+	{- The changes to make to the branch are calculated and applied to
+	 - the branch directly, rather than going through the journal,
+	 - which would be innefficient. (And the journal is not designed
+	 - to hold changes to every file in the branch at once.)
+	 -
+	 - When a file in the branch is changed by transition code,
+	 - that value is remembered and fed into the code for subsequent
+	 - transitions.
+	 -}
+	run [] = noop
+	run changers = do
+		trustmap <- calcTrustMap <$> getRaw trustLog
+		fs <- branchFiles
+		hasher <- inRepo hashObjectStart
+		forM_ fs $ \f -> do
+			content <- getRaw f
+			apply changers hasher f content trustmap
+		liftIO $ hashObjectStop hasher
+	apply [] _ _ _ _ = return ()
+	apply (changer:rest) hasher file content trustmap =
+		case changer file content trustmap of
+			RemoveFile -> do
+				Annex.Queue.addUpdateIndex
+					=<< inRepo (Git.UpdateIndex.unstageFile file)
+				-- File is deleted; can't run any other
+				-- transitions on it.
+				return ()
+			ChangeFile content' -> do
+				sha <- inRepo $ hashObject BlobObject content'
+				Annex.Queue.addUpdateIndex $ Git.UpdateIndex.pureStreamer $
+					Git.UpdateIndex.updateIndexLine sha FileBlob (asTopFilePath file)
+				apply rest hasher file content' trustmap
+			PreserveFile ->
+				apply rest hasher file content trustmap
+
+checkBranchDifferences :: Git.Ref -> Annex ()
+checkBranchDifferences ref = do
+	theirdiffs <- allDifferences . parseDifferencesLog . decodeBS
+		<$> catFile ref differenceLog
+	mydiffs <- annexDifferences <$> Annex.getGitConfig
+	when (theirdiffs /= mydiffs) $
+		error "Remote repository is tuned in incompatable way; cannot be merged with local repository."

Annex/Branch/Transitions.hs

@@ -0,0 +1,64 @@
+{- git-annex branch transitions
+ -
+ - Copyright 2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.Branch.Transitions (
+	FileTransition(..),
+	getTransitionCalculator
+) where
+
+import Logs
+import Logs.Transitions
+import qualified Logs.UUIDBased as UUIDBased
+import qualified Logs.Presence.Pure as Presence
+import qualified Logs.Chunk.Pure as Chunk
+import Types.TrustLevel
+import Types.UUID
+
+import qualified Data.Map as M
+import Data.Default
+
+data FileTransition
+	= ChangeFile String
+	| RemoveFile
+	| PreserveFile
+
+type TransitionCalculator = FilePath -> String -> TrustMap -> FileTransition
+
+getTransitionCalculator :: Transition -> Maybe TransitionCalculator
+getTransitionCalculator ForgetGitHistory = Nothing
+getTransitionCalculator ForgetDeadRemotes = Just dropDead
+
+dropDead :: FilePath -> String -> TrustMap -> FileTransition
+dropDead f content trustmap = case getLogVariety f of
+	Just UUIDBasedLog
+		-- Don't remove the dead repo from the trust log,
+		-- because git remotes may still exist, and they need
+		-- to still know it's dead.
+		| f == trustLog -> PreserveFile
+		| otherwise -> ChangeFile $ UUIDBased.showLog id $ dropDeadFromMapLog trustmap id $ UUIDBased.parseLog Just content
+	Just NewUUIDBasedLog -> ChangeFile $
+		UUIDBased.showLogNew id $ dropDeadFromMapLog trustmap id $ UUIDBased.parseLogNew Just content
+	Just (ChunkLog _) -> ChangeFile $
+		Chunk.showLog $ dropDeadFromMapLog trustmap fst $ Chunk.parseLog content
+	Just (PresenceLog _) ->
+		let newlog = Presence.compactLog $ dropDeadFromPresenceLog trustmap $ Presence.parseLog content
+		in if null newlog
+			then RemoveFile
+			else ChangeFile $ Presence.showLog newlog
+	Just OtherLog -> PreserveFile
+	Nothing -> PreserveFile
+
+dropDeadFromMapLog :: Ord k => TrustMap -> (k -> UUID) -> M.Map k v -> M.Map k v
+dropDeadFromMapLog trustmap getuuid = M.filterWithKey $ \k _v -> notDead trustmap getuuid k
+
+{- Presence logs can contain UUIDs or other values. Any line that matches
+ - a dead uuid is dropped; any other values are passed through. -}
+dropDeadFromPresenceLog :: TrustMap -> [Presence.LogLine] -> [Presence.LogLine]
+dropDeadFromPresenceLog trustmap = filter $ notDead trustmap (toUUID . Presence.info)
+
+notDead :: TrustMap -> (v -> UUID) -> v -> Bool
+notDead trustmap a v = M.findWithDefault def (a v) trustmap /= DeadTrusted

Annex/BranchState.hs

@@ -0,0 +1,43 @@
+{- git-annex branch state management
+ -
+ - Runtime state about the git-annex branch.
+ -
+ - Copyright 2011-2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.BranchState where
+
+import Common.Annex
+import Types.BranchState
+import qualified Annex
+
+getState :: Annex BranchState
+getState = Annex.getState Annex.branchstate
+
+setState :: BranchState -> Annex ()
+setState state = Annex.changeState $ \s -> s { Annex.branchstate = state }
+
+changeState :: (BranchState -> BranchState) -> Annex ()
+changeState changer = setState =<< changer <$> getState
+
+{- Runs an action to check that the index file exists, if it's not been
+ - checked before in this run of git-annex. -}
+checkIndexOnce :: Annex () -> Annex ()
+checkIndexOnce a = unlessM (indexChecked <$> getState) $ do
+	a
+	changeState $ \s -> s { indexChecked = True }
+
+{- Runs an action to update the branch, if it's not been updated before
+ - in this run of git-annex. -}
+runUpdateOnce :: Annex () -> Annex ()
+runUpdateOnce a = unlessM (branchUpdated <$> getState) $ do
+	a
+	disableUpdate
+
+{- Avoids updating the branch. A useful optimisation when the branch
+ - is known to have not changed, or git-annex won't be relying on info
+ - from it. -}
+disableUpdate :: Annex ()
+disableUpdate = changeState $ \s -> s { branchUpdated = True }

Annex/CatFile.hs

@@ -0,0 +1,158 @@
+{- git cat-file interface, with handle automatically stored in the Annex monad
+ -
+ - Copyright 2011-2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.CatFile (
+	catFile,
+	catFileDetails,
+	catObject,
+	catTree,
+	catObjectDetails,
+	catFileHandle,
+	catFileStop,
+	catKey,
+	catKeyFile,
+	catKeyFileHEAD,
+	catLink,
+) where
+
+import qualified Data.ByteString.Lazy as L
+import qualified Data.Map as M
+import System.PosixCompat.Types
+
+import Common.Annex
+import qualified Git
+import qualified Git.CatFile
+import qualified Annex
+import Git.Types
+import Git.FilePath
+import Git.FileMode
+import qualified Git.Ref
+
+catFile :: Git.Branch -> FilePath -> Annex L.ByteString
+catFile branch file = do
+	h <- catFileHandle
+	liftIO $ Git.CatFile.catFile h branch file
+
+catFileDetails :: Git.Branch -> FilePath -> Annex (Maybe (L.ByteString, Sha, ObjectType))
+catFileDetails branch file = do
+	h <- catFileHandle
+	liftIO $ Git.CatFile.catFileDetails h branch file
+
+catObject :: Git.Ref -> Annex L.ByteString
+catObject ref = do
+	h <- catFileHandle
+	liftIO $ Git.CatFile.catObject h ref
+
+catTree :: Git.Ref -> Annex [(FilePath, FileMode)]
+catTree ref = do
+	h <- catFileHandle
+	liftIO $ Git.CatFile.catTree h ref
+
+catObjectDetails :: Git.Ref -> Annex (Maybe (L.ByteString, Sha, ObjectType))
+catObjectDetails ref = do
+	h <- catFileHandle
+	liftIO $ Git.CatFile.catObjectDetails h ref
+
+{- There can be multiple index files, and a different cat-file is needed
+ - for each. This is selected by setting GIT_INDEX_FILE in the gitEnv. -}
+catFileHandle :: Annex Git.CatFile.CatFileHandle
+catFileHandle = do
+	m <- Annex.getState Annex.catfilehandles
+	indexfile <- fromMaybe "" . maybe Nothing (lookup "GIT_INDEX_FILE")
+		<$> fromRepo gitEnv
+	case M.lookup indexfile m of
+		Just h -> return h
+		Nothing -> do
+			h <- inRepo Git.CatFile.catFileStart
+			let m' = M.insert indexfile h m
+			Annex.changeState $ \s -> s { Annex.catfilehandles = m' }
+			return h
+
+{- Stops all running cat-files. Should only be run when it's known that
+ - nothing is using the handles, eg at shutdown. -}
+catFileStop :: Annex ()
+catFileStop = do
+	m <- Annex.withState $ \s ->
+		(s { Annex.catfilehandles = M.empty }, Annex.catfilehandles s)
+	liftIO $ mapM_ Git.CatFile.catFileStop (M.elems m)
+
+{- From the Sha or Ref of a symlink back to the key.
+ -
+ - Requires a mode witness, to guarantee that the file is a symlink.
+ -}
+catKey :: Ref -> FileMode -> Annex (Maybe Key)
+catKey = catKey' True
+
+catKey' :: Bool -> Sha -> FileMode -> Annex (Maybe Key)
+catKey' modeguaranteed sha mode
+	| isSymLink mode = do
+		l <- catLink modeguaranteed sha
+		return $ if isLinkToAnnex l
+			then fileKey $ takeFileName l
+			else Nothing
+	| otherwise = return Nothing
+
+{- Gets a symlink target. -}
+catLink :: Bool -> Sha -> Annex String
+catLink modeguaranteed sha = fromInternalGitPath . decodeBS <$> get
+  where
+	-- If the mode is not guaranteed to be correct, avoid
+	-- buffering the whole file content, which might be large.
+	-- 8192 is enough if it really is a symlink.
+	get
+		| modeguaranteed = catObject sha
+		| otherwise = L.take 8192 <$> catObject sha
+
+{- Looks up the key corresponding to the Ref using the running cat-file.
+ -
+ - Currently this always has to look in HEAD, because cat-file --batch
+ - does not offer a way to specify that we want to look up a tree object
+ - in the index. So if the index has a file staged not as a symlink,
+ - and it is a symlink in head, the wrong mode is gotten.
+ - Also, we have to assume the file is a symlink if it's not yet committed
+ - to HEAD. For these reasons, modeguaranteed is not set.
+ -}
+catKeyChecked :: Bool -> Ref -> Annex (Maybe Key)
+catKeyChecked needhead ref@(Ref r) =
+	catKey' False ref =<< findmode <$> catTree treeref
+  where
+	pathparts = split "/" r
+	dir = intercalate "/" $ take (length pathparts - 1) pathparts
+	file = fromMaybe "" $ lastMaybe pathparts
+	treeref = Ref $ if needhead then "HEAD" ++ dir ++ "/" else dir ++ "/"
+	findmode = fromMaybe symLinkMode . headMaybe .
+		 map snd . filter (\p -> fst p == file)
+
+{- From a file in the repository back to the key.
+ -
+ - Ideally, this should reflect the key that's staged in the index,
+ - not the key that's committed to HEAD. Unfortunately, git cat-file
+ - does not refresh the index file after it's started up, so things
+ - newly staged in the index won't show up. It does, however, notice
+ - when branches change.
+ -
+ - For command-line git-annex use, that doesn't matter. It's perfectly
+ - reasonable for things staged in the index after the currently running
+ - git-annex process to not be noticed by it. However, we do want to see
+ - what's in the index, since it may have uncommitted changes not in HEAD
+ -
+ - For the assistant, this is much more of a problem, since it commits
+ - files and then needs to be able to immediately look up their keys.
+ - OTOH, the assistant doesn't keep changes staged in the index for very
+ - long at all before committing them -- and it won't look at the keys
+ - of files until after committing them.
+ -
+ - So, this gets info from the index, unless running as a daemon.
+ -}
+catKeyFile :: FilePath -> Annex (Maybe Key)
+catKeyFile f = ifM (Annex.getState Annex.daemon)
+	( catKeyFileHEAD f
+	, catKeyChecked True $ Git.Ref.fileRef f
+	)
+
+catKeyFileHEAD :: FilePath -> Annex (Maybe Key)
+catKeyFileHEAD f = catKeyChecked False $ Git.Ref.fileFromRef Git.Ref.headRef f

Annex/CheckAttr.hs

@@ -0,0 +1,35 @@
+{- git check-attr interface, with handle automatically stored in the Annex monad
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.CheckAttr (
+	checkAttr,
+	checkAttrHandle
+) where
+
+import Common.Annex
+import qualified Git.CheckAttr as Git
+import qualified Annex
+
+{- All gitattributes used by git-annex. -}
+annexAttrs :: [Git.Attr]
+annexAttrs =
+	[ "annex.backend"
+	, "annex.numcopies"
+	]
+
+checkAttr :: Git.Attr -> FilePath -> Annex String
+checkAttr attr file = do
+	h <- checkAttrHandle
+	liftIO $ Git.checkAttr h attr file
+
+checkAttrHandle :: Annex Git.CheckAttrHandle
+checkAttrHandle = maybe startup return =<< Annex.getState Annex.checkattrhandle
+  where
+	startup = do
+		h <- inRepo $ Git.checkAttrStart annexAttrs
+		Annex.changeState $ \s -> s { Annex.checkattrhandle = Just h }
+		return h

Annex/CheckIgnore.hs

@@ -0,0 +1,32 @@
+{- git check-ignore interface, with handle automatically stored in
+ - the Annex monad
+ -
+ - Copyright 2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.CheckIgnore (
+	checkIgnored,
+	checkIgnoreHandle
+) where
+
+import Common.Annex
+import qualified Git.CheckIgnore as Git
+import qualified Annex
+
+checkIgnored :: FilePath -> Annex Bool
+checkIgnored file = go =<< checkIgnoreHandle
+  where
+	go Nothing = return False
+	go (Just h) = liftIO $ Git.checkIgnored h file
+
+checkIgnoreHandle :: Annex (Maybe Git.CheckIgnoreHandle)
+checkIgnoreHandle = maybe startup return =<< Annex.getState Annex.checkignorehandle
+  where
+	startup = do
+		v <- inRepo Git.checkIgnoreStart
+		when (isNothing v) $
+			warning "The installed version of git is too old for .gitignores to be honored by git-annex."
+		Annex.changeState $ \s -> s { Annex.checkignorehandle = Just v }
+		return v

Annex/Content.hs

@@ -0,0 +1,637 @@
+{- git-annex file content managing
+ -
+ - Copyright 2010-2014 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Annex.Content (
+	inAnnex,
+	inAnnexSafe,
+	inAnnexCheck,
+	lockContent,
+	getViaTmp,
+	getViaTmpChecked,
+	getViaTmpUnchecked,
+	prepGetViaTmpChecked,
+	prepTmp,
+	withTmp,
+	checkDiskSpace,
+	moveAnnex,
+	sendAnnex,
+	prepSendAnnex,
+	removeAnnex,
+	fromAnnex,
+	moveBad,
+	KeyLocation(..),
+	getKeysPresent,
+	saveState,
+	downloadUrl,
+	preseedTmp,
+	freezeContent,
+	thawContent,
+	dirKeys,
+	withObjectLoc,
+) where
+
+import System.IO.Unsafe (unsafeInterleaveIO)
+
+import Common.Annex
+import Logs.Location
+import qualified Git
+import qualified Annex
+import qualified Annex.Queue
+import qualified Annex.Branch
+import Utility.DiskFree
+import Utility.FileMode
+import qualified Annex.Url as Url
+import Types.Key
+import Utility.DataUnits
+import Utility.CopyFile
+import Config
+import Git.SharedRepository
+import Annex.Perms
+import Annex.Link
+import Annex.Content.Direct
+import Annex.ReplaceFile
+import Utility.LockFile
+
+{- Checks if a given key's content is currently present. -}
+inAnnex :: Key -> Annex Bool
+inAnnex key = inAnnexCheck key $ liftIO . doesFileExist
+
+{- Runs an arbitrary check on a key's content. -}
+inAnnexCheck :: Key -> (FilePath -> Annex Bool) -> Annex Bool
+inAnnexCheck key check = inAnnex' id False check key
+
+{- Generic inAnnex, handling both indirect and direct mode.
+ -
+ - In direct mode, at least one of the associated files must pass the
+ - check. Additionally, the file must be unmodified.
+ -}
+inAnnex' :: (a -> Bool) -> a -> (FilePath -> Annex a) -> Key -> Annex a
+inAnnex' isgood bad check key = withObjectLoc key checkindirect checkdirect
+  where
+	checkindirect loc = do
+		whenM (fromRepo Git.repoIsUrl) $
+			error "inAnnex cannot check remote repo"
+		check loc
+	checkdirect [] = return bad
+	checkdirect (loc:locs) = do
+		r <- check loc
+		if isgood r
+			then ifM (goodContent key loc)
+				( return r
+				, checkdirect locs
+				)
+			else checkdirect locs
+
+{- A safer check; the key's content must not only be present, but
+ - is not in the process of being removed. -}
+inAnnexSafe :: Key -> Annex (Maybe Bool)
+inAnnexSafe key = inAnnex' (fromMaybe False) (Just False) go key
+  where
+	is_locked = Nothing
+	is_unlocked = Just True
+	is_missing = Just False
+
+	go contentfile = maybe (checkindirect contentfile) (checkdirect contentfile)
+		=<< contentLockFile key
+
+#ifndef mingw32_HOST_OS
+	checkindirect contentfile = liftIO $ checkOr is_missing contentfile
+	{- In direct mode, the content file must exist, but
+	 - the lock file generally won't exist unless a removal is in
+	 - process. -}
+	checkdirect contentfile lockfile = liftIO $
+		ifM (doesFileExist contentfile)
+			( checkOr is_unlocked lockfile
+			, return is_missing
+			)
+	checkOr d lockfile = do
+		v <- checkLocked lockfile
+		return $ case v of
+			Nothing -> d
+			Just True -> is_locked
+			Just False -> is_unlocked
+#else
+	checkindirect f = liftIO $ ifM (doesFileExist f)
+		( do
+			v <- lockShared f
+			case v of
+				Nothing -> return is_locked
+				Just lockhandle -> do
+					dropLock lockhandle
+					return is_unlocked
+		, return is_missing
+		)
+	{- In Windows, see if we can take a shared lock. If so, 
+	 - remove the lock file to clean up after ourselves. -}
+	checkdirect contentfile lockfile =
+		ifM (liftIO $ doesFileExist contentfile)
+			( modifyContent lockfile $ liftIO $ do
+				v <- lockShared lockfile
+				case v of
+					Nothing -> return is_locked
+					Just lockhandle -> do
+						dropLock lockhandle
+						void $ tryIO $ nukeFile lockfile
+						return is_unlocked
+			, return is_missing
+			)
+#endif
+
+{- Direct mode and especially Windows has to use a separate lock
+ - file from the content, since locking the actual content file
+ - would interfere with the user's use of it. -}
+contentLockFile :: Key -> Annex (Maybe FilePath)
+contentLockFile key = ifM isDirect
+	( Just <$> calcRepo (gitAnnexContentLock key)
+	, return Nothing
+	)
+
+newtype ContentLock = ContentLock Key
+
+{- Content is exclusively locked while running an action that might remove
+ - it. (If the content is not present, no locking is done.)
+ -}
+lockContent :: Key -> (ContentLock -> Annex a) -> Annex a
+lockContent key a = do
+	contentfile <- calcRepo $ gitAnnexLocation key
+	lockfile <- contentLockFile key
+	maybe noop setuplockfile lockfile
+	bracket
+		(lock contentfile lockfile)
+		(unlock lockfile)
+		(const $ a $ ContentLock key)
+  where
+	alreadylocked = error "content is locked"
+	setuplockfile lockfile = modifyContent lockfile $
+		void $ liftIO $ tryIO $
+			writeFile lockfile ""
+	cleanuplockfile lockfile = modifyContent lockfile $
+		void $ liftIO $ tryIO $
+			nukeFile lockfile
+#ifndef mingw32_HOST_OS
+	lock contentfile Nothing = liftIO $
+		opencontentforlock contentfile >>= dolock
+	lock _ (Just lockfile) = do
+		mode <- annexFileMode
+		liftIO $ createLockFile mode lockfile >>= dolock . Just
+	{- Since content files are stored with the write bit disabled, have
+	 - to fiddle with permissions to open for an exclusive lock. -}
+	opencontentforlock f = catchDefaultIO Nothing $ 
+		withModifiedFileMode f
+			(`unionFileModes` ownerWriteMode)
+			(openExistingLockFile f)
+	dolock Nothing = return Nothing
+	dolock (Just fd) = do
+		v <- tryIO $ setLock fd (WriteLock, AbsoluteSeek, 0, 0)
+		case v of
+			Left _ -> alreadylocked
+			Right _ -> return $ Just fd
+	unlock mlockfile mfd = do
+		maybe noop cleanuplockfile mlockfile
+		liftIO $ maybe noop closeFd mfd
+#else
+	lock _ (Just lockfile) = liftIO $
+		maybe alreadylocked (return . Just) =<< lockExclusive lockfile
+	lock _ Nothing = return Nothing
+	unlock mlockfile mlockhandle = do
+		liftIO $ maybe noop dropLock mlockhandle
+		maybe noop cleanuplockfile mlockfile
+#endif
+
+{- Runs an action, passing it a temporary filename to get,
+ - and if the action succeeds, moves the temp file into 
+ - the annex as a key's content. -}
+getViaTmp :: Key -> (FilePath -> Annex Bool) -> Annex Bool
+getViaTmp = getViaTmpChecked (return True)
+
+{- Like getViaTmp, but does not check that there is enough disk space
+ - for the incoming key. For use when the key content is already on disk
+ - and not being copied into place. -}
+getViaTmpUnchecked :: Key -> (FilePath -> Annex Bool) -> Annex Bool
+getViaTmpUnchecked = finishGetViaTmp (return True)
+
+getViaTmpChecked :: Annex Bool -> Key -> (FilePath -> Annex Bool) -> Annex Bool
+getViaTmpChecked check key action = 
+	prepGetViaTmpChecked key False $
+		finishGetViaTmp check key action
+
+{- Prepares to download a key via a tmp file, and checks that there is
+ - enough free disk space.
+ -
+ - When the temp file already exists, count the space it is using as
+ - free, since the download will overwrite it or resume.
+ -
+ - Wen there's enough free space, runs the download action.
+ -}
+prepGetViaTmpChecked :: Key -> a -> Annex a -> Annex a
+prepGetViaTmpChecked key unabletoget getkey = do
+	tmp <- fromRepo $ gitAnnexTmpObjectLocation key
+
+	e <- liftIO $ doesFileExist tmp
+	alreadythere <- liftIO $ if e
+		then getFileSize tmp
+		else return 0
+	ifM (checkDiskSpace Nothing key alreadythere)
+		( do
+			-- The tmp file may not have been left writable
+			when e $ thawContent tmp
+			getkey
+		, return unabletoget
+		)
+
+finishGetViaTmp :: Annex Bool -> Key -> (FilePath -> Annex Bool) -> Annex Bool
+finishGetViaTmp check key action = do
+	tmpfile <- prepTmp key
+	ifM (action tmpfile <&&> check)
+		( do
+			moveAnnex key tmpfile
+			logStatus key InfoPresent
+			return True
+		-- the tmp file is left behind, in case caller wants
+		-- to resume its transfer
+		, return False
+		)
+
+prepTmp :: Key -> Annex FilePath
+prepTmp key = do
+	tmp <- fromRepo $ gitAnnexTmpObjectLocation key
+	createAnnexDirectory (parentDir tmp)
+	return tmp
+
+{- Creates a temp file for a key, runs an action on it, and cleans up
+ - the temp file. If the action throws an exception, the temp file is
+ - left behind, which allows for resuming.
+ -}
+withTmp :: Key -> (FilePath -> Annex a) -> Annex a
+withTmp key action = do
+	tmp <- prepTmp key
+	res <- action tmp
+	liftIO $ nukeFile tmp
+	return res
+
+{- Checks that there is disk space available to store a given key,
+ - in a destination (or the annex) printing a warning if not. -}
+checkDiskSpace :: Maybe FilePath -> Key -> Integer -> Annex Bool
+checkDiskSpace destination key alreadythere = do
+	reserve <- annexDiskReserve <$> Annex.getGitConfig
+	free <- liftIO . getDiskFree =<< dir
+	force <- Annex.getState Annex.force
+	case (free, keySize key) of
+		(Just have, Just need) -> do
+			let ok = (need + reserve <= have + alreadythere) || force
+			unless ok $
+				needmorespace (need + reserve - have - alreadythere)
+			return ok
+		_ -> return True
+  where
+	dir = maybe (fromRepo gitAnnexDir) return destination
+	needmorespace n =
+		warning $ "not enough free space, need " ++ 
+			roughSize storageUnits True n ++
+			" more" ++ forcemsg
+	forcemsg = " (use --force to override this check or adjust annex.diskreserve)"
+
+{- Moves a key's content into .git/annex/objects/
+ -
+ - In direct mode, moves it to the associated file, or files.
+ -
+ - What if the key there already has content? This could happen for
+ - various reasons; perhaps the same content is being annexed again.
+ - Perhaps there has been a hash collision generating the keys.
+ -
+ - The current strategy is to assume that in this case it's safe to delete
+ - one of the two copies of the content; and the one already in the annex
+ - is left there, assuming it's the original, canonical copy.
+ -
+ - I considered being more paranoid, and checking that both files had
+ - the same content. Decided against it because A) users explicitly choose
+ - a backend based on its hashing properties and so if they're dealing
+ - with colliding files it's their own fault and B) adding such a check
+ - would not catch all cases of colliding keys. For example, perhaps 
+ - a remote has a key; if it's then added again with different content then
+ - the overall system now has two different peices of content for that
+ - key, and one of them will probably get deleted later. So, adding the
+ - check here would only raise expectations that git-annex cannot truely
+ - meet.
+ -}
+moveAnnex :: Key -> FilePath -> Annex ()
+moveAnnex key src = withObjectLoc key storeobject storedirect
+  where
+	storeobject dest = ifM (liftIO $ doesFileExist dest)
+		( alreadyhave
+		, modifyContent dest $ do
+			liftIO $ moveFile src dest
+			freezeContent dest
+		)
+	storeindirect = storeobject =<< calcRepo (gitAnnexLocation key)
+
+	{- In direct mode, the associated file's content may be locally
+	 - modified. In that case, it's preserved. However, the content
+	 - we're moving into the annex may be the only extant copy, so
+	 - it's important we not lose it. So, when the key's content
+	 - cannot be moved to any associated file, it's stored in indirect
+	 - mode.
+	 -}
+	storedirect = storedirect' storeindirect
+	storedirect' fallback [] = fallback
+	storedirect' fallback (f:fs) = do
+		thawContent src
+		v <- isAnnexLink f
+		if Just key == v
+			then do
+				updateInodeCache key src
+				replaceFile f $ liftIO . moveFile src
+				chmodContent f
+				forM_ fs $
+					addContentWhenNotPresent key f
+			else ifM (goodContent key f)
+				( storedirect' alreadyhave fs
+				, storedirect' fallback fs
+				)
+	
+	alreadyhave = liftIO $ removeFile src
+
+{- Runs an action to transfer an object's content.
+ -
+ - In direct mode, it's possible for the file to change as it's being sent.
+ - If this happens, runs the rollback action and returns False. The
+ - rollback action should remove the data that was transferred.
+ -}
+sendAnnex :: Key -> Annex () -> (FilePath -> Annex Bool) -> Annex Bool
+sendAnnex key rollback sendobject = go =<< prepSendAnnex key
+  where
+	go Nothing = return False
+	go (Just (f, checksuccess)) = do
+		r <- sendobject f
+		ifM checksuccess
+			( return r
+			, do
+				rollback
+				return False
+			)
+
+{- Returns a file that contains an object's content,
+ - and a check to run after the transfer is complete.
+ -
+ - In direct mode, it's possible for the file to change as it's being sent,
+ - and the check detects this case and returns False.
+ -
+ - Note that the returned check action is, in some cases, run in the
+ - Annex monad of the remote that is receiving the object, rather than
+ - the sender. So it cannot rely on Annex state.
+ -}
+prepSendAnnex :: Key -> Annex (Maybe (FilePath, Annex Bool))
+prepSendAnnex key = withObjectLoc key indirect direct
+  where
+	indirect f = return $ Just (f, return True)
+	direct [] = return Nothing
+	direct (f:fs) = do
+		cache <- recordedInodeCache key
+		-- check that we have a good file
+		ifM (sameInodeCache f cache)
+			( return $ Just (f, sameInodeCache f cache)
+			, direct fs
+			)
+
+{- Performs an action, passing it the location to use for a key's content.
+ -
+ - In direct mode, the associated files will be passed. But, if there are
+ - no associated files for a key, the indirect mode action will be
+ - performed instead. -}
+withObjectLoc :: Key -> (FilePath -> Annex a) -> ([FilePath] -> Annex a) -> Annex a
+withObjectLoc key indirect direct = ifM isDirect
+	( do
+		fs <- associatedFiles key
+		if null fs
+			then goindirect
+			else direct fs
+	, goindirect
+	)
+  where
+	goindirect = indirect =<< calcRepo (gitAnnexLocation key)
+
+cleanObjectLoc :: Key -> Annex () -> Annex ()
+cleanObjectLoc key cleaner = do
+	file <- calcRepo $ gitAnnexLocation key
+	void $ tryIO $ thawContentDir file
+	cleaner
+	liftIO $ removeparents file (3 :: Int)
+  where
+	removeparents _ 0 = noop
+	removeparents file n = do
+		let dir = parentDir file
+		maybe noop (const $ removeparents dir (n-1))
+			<=< catchMaybeIO $ removeDirectory dir
+
+{- Removes a key's file from .git/annex/objects/
+ -
+ - In direct mode, deletes the associated files or files, and replaces
+ - them with symlinks.
+ -}
+removeAnnex :: ContentLock -> Annex ()
+removeAnnex (ContentLock key) = withObjectLoc key remove removedirect
+  where
+	remove file = cleanObjectLoc key $ do
+		secureErase file
+		liftIO $ nukeFile file
+		removeInodeCache key
+	removedirect fs = do
+		cache <- recordedInodeCache key
+		removeInodeCache key
+		mapM_ (resetfile cache) fs
+	resetfile cache f = whenM (sameInodeCache f cache) $ do
+		l <- calcRepo $ gitAnnexLink f key
+		secureErase f
+		replaceFile f $ makeAnnexLink l
+
+{- Runs the secure erase command if set, otherwise does nothing.
+ - File may or may not be deleted at the end; caller is responsible for
+ - making sure it's deleted. -}
+secureErase :: FilePath -> Annex ()
+secureErase file = maybe noop go =<< annexSecureEraseCommand <$> Annex.getGitConfig
+  where
+	go basecmd = void $ liftIO $
+		boolSystem "sh" [Param "-c", Param $ gencmd basecmd]
+	gencmd = massReplace [ ("%file", shellEscape file) ]
+
+{- Moves a key's file out of .git/annex/objects/ -}
+fromAnnex :: Key -> FilePath -> Annex ()
+fromAnnex key dest = cleanObjectLoc key $ do
+	file <- calcRepo $ gitAnnexLocation key
+	thawContent file
+	liftIO $ moveFile file dest
+
+{- Moves a key out of .git/annex/objects/ into .git/annex/bad, and
+ - returns the file it was moved to. -}
+moveBad :: Key -> Annex FilePath
+moveBad key = do
+	src <- calcRepo $ gitAnnexLocation key
+	bad <- fromRepo gitAnnexBadDir
+	let dest = bad </> takeFileName src
+	createAnnexDirectory (parentDir dest)
+	cleanObjectLoc key $
+		liftIO $ moveFile src dest
+	logStatus key InfoMissing
+	return dest
+
+data KeyLocation = InAnnex | InRepository
+
+{- List of keys whose content exists in the specified location.
+ 
+ - InAnnex only lists keys under .git/annex/objects,
+ - while InRepository, in direct mode, also finds keys located in the
+ - work tree.
+ -
+ - Note that InRepository has to check whether direct mode files
+ - have goodContent.
+ -}
+getKeysPresent :: KeyLocation -> Annex [Key]
+getKeysPresent keyloc = do
+	direct <- isDirect
+	dir <- fromRepo gitAnnexObjectDir
+	s <- getstate direct
+	liftIO $ traverse s direct (2 :: Int) dir
+  where
+	traverse s direct depth dir = do
+		contents <- catchDefaultIO [] (dirContents dir)
+		if depth == 0
+			then do
+				contents' <- filterM (present s direct) contents
+				let keys = mapMaybe (fileKey . takeFileName) contents'
+				continue keys []
+			else do
+				let deeper = traverse s direct (depth - 1)
+				continue [] (map deeper contents)
+	continue keys [] = return keys
+	continue keys (a:as) = do
+		{- Force lazy traversal with unsafeInterleaveIO. -}
+		morekeys <- unsafeInterleaveIO a
+		continue (morekeys++keys) as
+
+	present _ False d = presentInAnnex d
+	present s True d = presentDirect s d <||> presentInAnnex d
+
+	presentInAnnex = doesFileExist . contentfile
+	contentfile d = d </> takeFileName d
+
+	presentDirect s d = case keyloc of
+		InAnnex -> return False
+		InRepository -> case fileKey (takeFileName d) of
+			Nothing -> return False
+			Just k -> Annex.eval s $ 
+				anyM (goodContent k) =<< associatedFiles k
+
+	{- In order to run Annex monad actions within unsafeInterleaveIO,
+	 - the current state is taken and reused. No changes made to this
+	 - state will be preserved. 
+	 -
+	 - As an optimsation, call inodesChanged to prime the state with
+	 - a cached value that will be used in the call to goodContent.
+	 -}
+	getstate direct = do
+		when direct $
+			void $ inodesChanged
+		Annex.getState id
+
+{- Things to do to record changes to content when shutting down.
+ -
+ - It's acceptable to avoid committing changes to the branch,
+ - especially if performing a short-lived action.
+ -}
+saveState :: Bool -> Annex ()
+saveState nocommit = doSideAction $ do
+	Annex.Queue.flush
+	unless nocommit $
+		whenM (annexAlwaysCommit <$> Annex.getGitConfig) $
+			Annex.Branch.commit "update"
+
+{- Downloads content from any of a list of urls. -}
+downloadUrl :: [Url.URLString] -> FilePath -> Annex Bool
+downloadUrl urls file = go =<< annexWebDownloadCommand <$> Annex.getGitConfig
+  where
+	go Nothing = Url.withUrlOptions $ \uo ->
+		anyM (\u -> Url.download u file uo) urls
+	go (Just basecmd) = liftIO $ anyM (downloadcmd basecmd) urls
+	downloadcmd basecmd url =
+		boolSystem "sh" [Param "-c", Param $ gencmd url basecmd]
+			<&&> doesFileExist file
+	gencmd url = massReplace
+		[ ("%file", shellEscape file)
+		, ("%url", shellEscape url)
+		]
+
+{- Copies a key's content, when present, to a temp file.
+ - This is used to speed up some rsyncs. -}
+preseedTmp :: Key -> FilePath -> Annex Bool
+preseedTmp key file = go =<< inAnnex key
+  where
+	go False = return False
+	go True = do
+		ok <- copy
+		when ok $ thawContent file
+		return ok
+	copy = ifM (liftIO $ doesFileExist file)
+		( return True
+		, do
+			s <- calcRepo $ gitAnnexLocation key
+			liftIO $ copyFileExternal CopyTimeStamps s file
+		)
+
+{- Blocks writing to an annexed file, and modifies file permissions to
+ - allow reading it, per core.sharedRepository setting. -}
+freezeContent :: FilePath -> Annex ()
+freezeContent file = unlessM crippledFileSystem $
+	liftIO . go =<< fromRepo getSharedRepository
+  where
+	go GroupShared = modifyFileMode file $
+		removeModes writeModes .
+		addModes [ownerReadMode, groupReadMode]
+	go AllShared = modifyFileMode file $
+		removeModes writeModes .
+		addModes readModes
+	go _ = modifyFileMode file $
+		removeModes writeModes .
+		addModes [ownerReadMode]
+
+{- Adjusts read mode of annexed file per core.sharedRepository setting. -}
+chmodContent :: FilePath -> Annex ()
+chmodContent file = unlessM crippledFileSystem $
+	liftIO . go =<< fromRepo getSharedRepository
+  where
+	go GroupShared = modifyFileMode file $
+		addModes [ownerReadMode, groupReadMode]
+	go AllShared = modifyFileMode file $
+		addModes readModes
+	go _ = modifyFileMode file $
+		addModes [ownerReadMode]
+
+{- Allows writing to an annexed file that freezeContent was called on
+ - before. -}
+thawContent :: FilePath -> Annex ()
+thawContent file = unlessM crippledFileSystem $
+	liftIO . go =<< fromRepo getSharedRepository
+  where
+	go GroupShared = groupWriteRead file
+	go AllShared = groupWriteRead file
+	go _ = allowWrite file
+
+{- Finds files directly inside a directory like gitAnnexBadDir 
+ - (not in subdirectories) and returns the corresponding keys. -}
+dirKeys :: (Git.Repo -> FilePath) -> Annex [Key]
+dirKeys dirspec = do
+	dir <- fromRepo dirspec
+	ifM (liftIO $ doesDirectoryExist dir)
+		( do
+			contents <- liftIO $ getDirectoryContents dir
+			files <- liftIO $ filterM doesFileExist $
+				map (dir </>) contents
+			return $ mapMaybe (fileKey . takeFileName) files
+		, return []
+		)
+

Annex/Content/Direct.hs

@@ -0,0 +1,263 @@
+{- git-annex file content managing for direct mode
+ -
+ - Copyright 2012-2014 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Annex.Content.Direct (
+	associatedFiles,
+	associatedFilesRelative,
+	removeAssociatedFile,
+	removeAssociatedFileUnchecked,
+	removeAssociatedFiles,
+	addAssociatedFile,
+	goodContent,
+	recordedInodeCache,
+	updateInodeCache,
+	addInodeCache,
+	writeInodeCache,
+	compareInodeCaches,
+	compareInodeCachesWith,
+	sameInodeCache,
+	elemInodeCaches,
+	sameFileStatus,
+	removeInodeCache,
+	toInodeCache,
+	inodesChanged,
+	createInodeSentinalFile,
+	addContentWhenNotPresent,
+	withTSDelta,
+	getTSDelta,
+) where
+
+import Common.Annex
+import qualified Annex
+import Annex.Perms
+import qualified Git
+import Utility.Tmp
+import Logs.Location
+import Utility.InodeCache
+import Utility.CopyFile
+import Annex.ReplaceFile
+import Annex.Link
+
+{- Absolute FilePaths of Files in the tree that are associated with a key. -}
+associatedFiles :: Key -> Annex [FilePath]
+associatedFiles key = do
+	files <- associatedFilesRelative key
+	top <- fromRepo Git.repoPath
+	return $ map (top </>) files
+
+{- List of files in the tree that are associated with a key, relative to
+ - the top of the repo. -}
+associatedFilesRelative :: Key -> Annex [FilePath] 
+associatedFilesRelative key = do
+	mapping <- calcRepo $ gitAnnexMapping key
+	liftIO $ catchDefaultIO [] $ withFile mapping ReadMode $ \h -> do
+		fileEncoding h
+		-- Read strictly to ensure the file is closed
+		-- before changeAssociatedFiles tries to write to it.
+		-- (Especially needed on Windows.)
+		lines <$> hGetContentsStrict h
+
+{- Changes the associated files information for a key, applying a
+ - transformation to the list. Returns new associatedFiles value. -}
+changeAssociatedFiles :: Key -> ([FilePath] -> [FilePath]) -> Annex [FilePath]
+changeAssociatedFiles key transform = do
+	mapping <- calcRepo $ gitAnnexMapping key
+	files <- associatedFilesRelative key
+	let files' = transform files
+	when (files /= files') $
+		modifyContent mapping $
+			liftIO $ viaTmp writeFileAnyEncoding mapping $
+				unlines files'
+	top <- fromRepo Git.repoPath
+	return $ map (top </>) files'
+
+{- Removes the list of associated files. -}
+removeAssociatedFiles :: Key -> Annex ()
+removeAssociatedFiles key = do
+	mapping <- calcRepo $ gitAnnexMapping key
+	modifyContent mapping $
+		liftIO $ nukeFile mapping
+
+{- Removes an associated file. Returns new associatedFiles value.
+ - Checks if this was the last copy of the object, and updates location
+ - log. -}
+removeAssociatedFile :: Key -> FilePath -> Annex [FilePath]
+removeAssociatedFile key file = do
+	fs <- removeAssociatedFileUnchecked key file
+	when (null fs) $
+		logStatus key InfoMissing
+	return fs
+
+{- Removes an associated file. Returns new associatedFiles value. -}
+removeAssociatedFileUnchecked :: Key -> FilePath -> Annex [FilePath]
+removeAssociatedFileUnchecked key file = do
+	file' <- normaliseAssociatedFile file
+	changeAssociatedFiles key $ filter (/= file')
+
+{- Adds an associated file. Returns new associatedFiles value. -}
+addAssociatedFile :: Key -> FilePath -> Annex [FilePath]
+addAssociatedFile key file = do
+	file' <- normaliseAssociatedFile file
+	changeAssociatedFiles key $ \files ->
+		if file' `elem` files
+			then files
+			else file':files
+
+{- Associated files are always stored relative to the top of the repository.
+ - The input FilePath is relative to the CWD, or is absolute. -}
+normaliseAssociatedFile :: FilePath -> Annex FilePath
+normaliseAssociatedFile file = do
+	top <- fromRepo Git.repoPath
+	liftIO $ relPathDirToFile top file
+
+{- Checks if a file in the tree, associated with a key, has not been modified.
+ -
+ - To avoid needing to fsck the file's content, which can involve an
+ - expensive checksum, this relies on a cache that contains the file's
+ - expected mtime and inode.
+ -}
+goodContent :: Key -> FilePath -> Annex Bool
+goodContent key file = sameInodeCache file =<< recordedInodeCache key
+
+{- Gets the recorded inode cache for a key. 
+ -
+ - A key can be associated with multiple files, so may return more than
+ - one. -}
+recordedInodeCache :: Key -> Annex [InodeCache]
+recordedInodeCache key = withInodeCacheFile key $ \f ->
+	liftIO $ catchDefaultIO [] $
+		mapMaybe readInodeCache . lines <$> readFileStrict f
+
+{- Caches an inode for a file.
+ -
+ - Anything else already cached is preserved.
+ -}
+updateInodeCache :: Key -> FilePath -> Annex ()
+updateInodeCache key file = maybe noop (addInodeCache key)
+	=<< withTSDelta (liftIO . genInodeCache file)
+
+{- Adds another inode to the cache for a key. -}
+addInodeCache :: Key -> InodeCache -> Annex ()
+addInodeCache key cache = do
+	oldcaches <- recordedInodeCache key
+	unlessM (elemInodeCaches cache oldcaches) $
+		writeInodeCache key (cache:oldcaches)
+
+{- Writes inode cache for a key. -}
+writeInodeCache :: Key -> [InodeCache] -> Annex ()
+writeInodeCache key caches = withInodeCacheFile key $ \f -> 
+	modifyContent f $
+		liftIO $ writeFile f $
+			unlines $ map showInodeCache caches
+
+{- Removes an inode cache. -}
+removeInodeCache :: Key -> Annex ()
+removeInodeCache key = withInodeCacheFile key $ \f ->
+	modifyContent f $
+		liftIO $ nukeFile f
+
+withInodeCacheFile :: Key -> (FilePath -> Annex a) -> Annex a
+withInodeCacheFile key a = a =<< calcRepo (gitAnnexInodeCache key)
+
+{- Checks if a InodeCache matches the current version of a file. -}
+sameInodeCache :: FilePath -> [InodeCache] -> Annex Bool
+sameInodeCache _ [] = return False
+sameInodeCache file old = go =<< withTSDelta (liftIO . genInodeCache file)
+  where
+	go Nothing = return False
+	go (Just curr) = elemInodeCaches curr old
+
+{- Checks if a FileStatus matches the recorded InodeCache of a file. -}
+sameFileStatus :: Key -> FilePath -> FileStatus -> Annex Bool
+sameFileStatus key f status = do
+	old <- recordedInodeCache key
+	curr <- withTSDelta $ \delta -> liftIO $ toInodeCache delta f status
+	case (old, curr) of
+		(_, Just c) -> elemInodeCaches c old
+		([], Nothing) -> return True
+		_ -> return False
+
+{- If the inodes have changed, only the size and mtime are compared. -}
+compareInodeCaches :: InodeCache -> InodeCache -> Annex Bool
+compareInodeCaches x y
+	| compareStrong x y = return True
+	| otherwise = ifM inodesChanged
+		( return $ compareWeak x y
+		, return False
+		)
+
+elemInodeCaches :: InodeCache -> [InodeCache] -> Annex Bool
+elemInodeCaches _ [] = return False
+elemInodeCaches c (l:ls) = ifM (compareInodeCaches c l)
+	( return True
+	, elemInodeCaches c ls
+	)
+
+compareInodeCachesWith :: Annex InodeComparisonType
+compareInodeCachesWith = ifM inodesChanged ( return Weakly, return Strongly )
+
+{- Copies the contentfile to the associated file, if the associated
+ - file has no content. If the associated file does have content,
+ - even if the content differs, it's left unchanged. -}
+addContentWhenNotPresent :: Key -> FilePath -> FilePath -> Annex ()
+addContentWhenNotPresent key contentfile associatedfile = do
+	v <- isAnnexLink associatedfile
+	when (Just key == v) $
+		replaceFile associatedfile $
+			liftIO . void . copyFileExternal CopyAllMetaData contentfile
+	updateInodeCache key associatedfile	
+
+{- Some filesystems get new inodes each time they are mounted.
+ - In order to work on such a filesystem, a sentinal file is used to detect
+ - when the inodes have changed.
+ -
+ - If the sentinal file does not exist, we have to assume that the
+ - inodes have changed.
+ -}
+inodesChanged :: Annex Bool
+inodesChanged = sentinalInodesChanged <$> sentinalStatus
+
+withTSDelta :: (TSDelta -> Annex a) -> Annex a
+withTSDelta a = a =<< getTSDelta
+
+getTSDelta :: Annex TSDelta
+#ifdef mingw32_HOST_OS
+getTSDelta = sentinalTSDelta <$> sentinalStatus
+#else
+getTSDelta = pure noTSDelta -- optimisation
+#endif
+
+sentinalStatus :: Annex SentinalStatus
+sentinalStatus = maybe check return =<< Annex.getState Annex.sentinalstatus
+  where
+	check = do
+		sc <- liftIO . checkSentinalFile =<< annexSentinalFile
+		Annex.changeState $ \s -> s { Annex.sentinalstatus = Just sc }
+		return sc
+
+{- The sentinal file is only created when first initializing a repository.
+ - If there are any annexed objects in the repository already, creating
+ - the file would invalidate their inode caches. -}
+createInodeSentinalFile :: Annex ()
+createInodeSentinalFile = unlessM (alreadyexists <||> hasobjects) $ do
+	s <- annexSentinalFile
+	createAnnexDirectory (parentDir (sentinalFile s))
+	liftIO $ writeSentinalFile s
+  where
+	alreadyexists = liftIO. sentinalFileExists =<< annexSentinalFile
+	hasobjects = liftIO . doesDirectoryExist =<< fromRepo gitAnnexObjectDir
+
+annexSentinalFile :: Annex SentinalFile
+annexSentinalFile = do
+	sentinalfile <- fromRepo gitAnnexInodeSentinal
+	sentinalcachefile <- fromRepo gitAnnexInodeSentinalCache
+	return $ SentinalFile
+		{ sentinalFile = sentinalfile
+		, sentinalCacheFile = sentinalcachefile
+		}

Annex/Difference.hs

@@ -0,0 +1,58 @@
+{- git-annex repository differences
+ -
+ - Copyright 2015 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.Difference (
+	module Types.Difference,
+	setDifferences,
+) where
+
+import Common.Annex
+import Types.Difference
+import Logs.Difference
+import Config
+import Annex.UUID
+import Logs.UUID
+import Annex.Version
+import qualified Annex
+
+import qualified Data.Map as M
+
+-- Differences are only allowed to be tweaked when initializing a
+-- repository for the first time, and then only if there is not another
+-- known uuid. If the repository was cloned from elsewhere, it inherits
+-- the existing settings.
+--
+-- Must be called before setVersion, so it can check if this is the first
+-- time the repository is being initialized.
+setDifferences :: Annex ()
+setDifferences = do
+	u <- getUUID
+	otherds <- allDifferences <$> recordedDifferences
+	ds <- mappend otherds . annexDifferences <$> Annex.getGitConfig
+	when (ds /= mempty) $ do
+		ds' <- ifM (isJust <$> getVersion)
+			( do
+				oldds <- recordedDifferencesFor u
+				when (ds /= oldds) $
+					warning $ "Cannot change tunable parameters in already initialized repository."
+				return oldds
+			, if otherds == mempty
+				then ifM (not . null . filter (/= u) . M.keys <$> uuidMap)
+					( do
+						warning "Cannot change tunable parameters in a clone of an existing repository."
+						return mempty
+					, return ds
+					)
+				else if otherds /= ds
+					then do
+						warning "The specified tunable parameters differ from values being used in other clones of this repository."
+						return otherds
+					else return ds
+			)
+		forM_ (listDifferences ds') $ \d ->
+			setConfig (ConfigKey $ differenceConfigKey d) (differenceConfigVal d)
+		recordDifferences ds' u

Annex/DirHashes.hs

@@ -0,0 +1,86 @@
+{- git-annex file locations
+ -
+ - Copyright 2010-2015 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.DirHashes (
+	Hasher,
+	HashLevels(..),
+	objectHashLevels,
+	branchHashLevels,
+	branchHashDir,
+	dirHashes,
+	hashDirMixed,
+	hashDirLower,
+) where
+
+import Data.Bits
+import Data.Word
+import Data.Hash.MD5
+import Data.Default
+
+import Common
+import Types.Key
+import Types.GitConfig
+import Types.Difference
+
+type Hasher = Key -> FilePath
+
+-- Number of hash levels to use. 2 is the default.
+newtype HashLevels = HashLevels Int
+
+instance Default HashLevels where
+	def = HashLevels 2
+
+objectHashLevels :: GitConfig -> HashLevels
+objectHashLevels = configHashLevels OneLevelObjectHash
+
+branchHashLevels :: GitConfig -> HashLevels
+branchHashLevels = configHashLevels OneLevelBranchHash
+
+configHashLevels :: Difference -> GitConfig -> HashLevels
+configHashLevels d config
+	| hasDifference d (annexDifferences config) = HashLevels 1
+	| otherwise = def
+
+branchHashDir :: GitConfig -> Key -> String
+branchHashDir config key = hashDirLower (branchHashLevels config) key
+
+{- Two different directory hashes may be used. The mixed case hash
+ - came first, and is fine, except for the problem of case-strict
+ - filesystems such as Linux VFAT (mounted with shortname=mixed),
+ - which do not allow using a directory "XX" when "xx" already exists.
+ - To support that, most repositories use the lower case hash for new data. -}
+dirHashes :: [HashLevels -> Hasher]
+dirHashes = [hashDirLower, hashDirMixed]
+
+hashDirs :: HashLevels -> Int -> String -> FilePath
+hashDirs (HashLevels 1) sz s = addTrailingPathSeparator $ take sz s
+hashDirs _ sz s = addTrailingPathSeparator $ take sz s </> drop sz s
+
+hashDirMixed :: HashLevels -> Hasher
+hashDirMixed n k = hashDirs n 2 $ take 4 $ display_32bits_as_dir =<< [a,b,c,d]
+  where
+	ABCD (a,b,c,d) = md5 $ md5FilePath $ key2file $ nonChunkKey k
+
+hashDirLower :: HashLevels -> Hasher
+hashDirLower n k = hashDirs n 3 $ take 6 $ md5s $ md5FilePath $ key2file $ nonChunkKey k
+
+{- modified version of display_32bits_as_hex from Data.Hash.MD5
+ -   Copyright (C) 2001 Ian Lynagh 
+ -   License: Either BSD or GPL
+ -}
+display_32bits_as_dir :: Word32 -> String
+display_32bits_as_dir w = trim $ swap_pairs cs
+  where 
+	-- Need 32 characters to use. To avoid inaverdently making
+	-- a real word, use letters that appear less frequently.
+	chars = ['0'..'9'] ++ "zqjxkmvwgpfZQJXKMVWGPF"
+	cs = map (\x -> getc $ (shiftR w (6*x)) .&. 31) [0..7]
+	getc n = chars !! fromIntegral n
+	swap_pairs (x1:x2:xs) = x2:x1:swap_pairs xs
+	swap_pairs _ = []
+	-- Last 2 will always be 00, so omit.
+	trim = take 6

Annex/Direct.hs

@@ -0,0 +1,456 @@
+{- git-annex direct mode
+ -
+ - Copyright 2012-2014 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.Direct where
+
+import Common.Annex
+import qualified Annex
+import qualified Git
+import qualified Git.LsFiles
+import qualified Git.Merge
+import qualified Git.DiffTree as DiffTree
+import qualified Git.Config
+import qualified Git.Ref
+import qualified Git.Branch
+import Git.Sha
+import Git.FilePath
+import Git.Types
+import Config
+import Annex.CatFile
+import qualified Annex.Queue
+import Logs.Location
+import Backend
+import Types.KeySource
+import Annex.Content
+import Annex.Content.Direct
+import Annex.Link
+import Utility.InodeCache
+import Utility.CopyFile
+import Annex.Perms
+import Annex.ReplaceFile
+import Annex.VariantFile
+import Git.Index
+import Annex.Index
+import Annex.LockFile
+
+{- Uses git ls-files to find files that need to be committed, and stages
+ - them into the index. Returns True if some changes were staged. -}
+stageDirect :: Annex Bool
+stageDirect = do
+	Annex.Queue.flush
+	top <- fromRepo Git.repoPath
+	(l, cleanup) <- inRepo $ Git.LsFiles.stagedOthersDetails [top]
+	forM_ l go
+	void $ liftIO cleanup
+	staged <- Annex.Queue.size
+	Annex.Queue.flush
+	return $ staged /= 0
+  where
+	{- Determine what kind of modified or deleted file this is, as
+	 - efficiently as we can, by getting any key that's associated
+	 - with it in git, as well as its stat info. -}
+	go (file, Just sha, Just mode) = withTSDelta $ \delta -> do
+		shakey <- catKey sha mode
+		mstat <- liftIO $ catchMaybeIO $ getSymbolicLinkStatus file
+		mcache <- liftIO $ maybe (pure Nothing) (toInodeCache delta file) mstat
+		filekey <- isAnnexLink file
+		case (shakey, filekey, mstat, mcache) of
+			(_, Just key, _, _)
+				| shakey == filekey -> noop
+				{- A changed symlink. -}
+				| otherwise -> stageannexlink file key
+			(Just key, _, _, Just cache) -> do
+				{- All direct mode files will show as
+				 - modified, so compare the cache to see if
+				 - it really was. -}
+				oldcache <- recordedInodeCache key
+				case oldcache of
+					[] -> modifiedannexed file key cache
+					_ -> unlessM (elemInodeCaches cache oldcache) $
+						modifiedannexed file key cache
+			(Just key, _, Nothing, _) -> deletedannexed file key
+			(Nothing, _, Nothing, _) -> deletegit file
+			(_, _, Just _, _) -> addgit file
+	go _ = noop
+
+	modifiedannexed file oldkey cache = do
+		void $ removeAssociatedFile oldkey file
+		void $ addDirect file cache
+	
+	deletedannexed file key = do
+		void $ removeAssociatedFile key file
+		deletegit file
+	
+	stageannexlink file key = do
+		l <- calcRepo $ gitAnnexLink file key
+		stageSymlink file =<< hashSymlink l
+		void $ addAssociatedFile key file
+
+	addgit file = Annex.Queue.addCommand "add" [Param "-f"] [file]
+
+	deletegit file = Annex.Queue.addCommand "rm" [Param "-qf"] [file]
+
+{- Run before a commit to update direct mode bookeeping to reflect the
+ - staged changes being committed. -}
+preCommitDirect :: Annex Bool
+preCommitDirect = do
+	(diffs, clean) <- inRepo $ DiffTree.diffIndex Git.Ref.headRef
+	makeabs <- flip fromTopFilePath <$> gitRepo
+	forM_ diffs (go makeabs)
+	liftIO clean
+  where
+	go makeabs diff = do
+		withkey (DiffTree.srcsha diff) (DiffTree.srcmode diff) removeAssociatedFile
+		withkey (DiffTree.dstsha diff) (DiffTree.dstmode diff) addAssociatedFile
+	  where
+		withkey sha mode a = when (sha /= nullSha) $ do
+			k <- catKey sha mode
+			case k of
+				Nothing -> noop
+				Just key -> void $ a key $
+					makeabs $ DiffTree.file diff
+
+{- Adds a file to the annex in direct mode. Can fail, if the file is
+ - modified or deleted while it's being added. -}
+addDirect :: FilePath -> InodeCache -> Annex Bool
+addDirect file cache = do
+	showStart "add" file
+	let source = KeySource
+		{ keyFilename = file
+		, contentLocation = file
+		, inodeCache = Just cache
+		}
+	got =<< genKey source =<< chooseBackend file
+  where
+	got Nothing = do
+		showEndFail
+		return False
+	got (Just (key, _)) = ifM (sameInodeCache file [cache])
+		( do
+			l <- calcRepo $ gitAnnexLink file key
+			stageSymlink file =<< hashSymlink l
+			addInodeCache key cache
+			void $ addAssociatedFile key file
+			logStatus key InfoPresent
+			showEndOk
+			return True
+		, do
+			showEndFail
+			return False
+		)
+
+{- In direct mode, git merge would usually refuse to do anything, since it
+ - sees present direct mode files as type changed files.
+ -
+ - So, to handle a merge, it's run with the work tree set to a temp
+ - directory, and the merge is staged into a copy of the index.
+ - Then the work tree is updated to reflect the merge, and
+ - finally, the merge is committed and the real index updated.
+ -
+ - A lock file is used to avoid races with any other caller of mergeDirect.
+ - 
+ - To avoid other git processes from making change to the index while our
+ - merge is in progress, the index lock file is used as the temp index
+ - file. This is the same as what git does when updating the index
+ - normally.
+ -}
+mergeDirect :: Maybe Git.Ref -> Maybe Git.Ref -> Git.Branch -> Annex Bool -> Git.Branch.CommitMode -> Annex Bool
+mergeDirect startbranch oldref branch resolvemerge commitmode = exclusively $ do
+	reali <- liftIO . absPath =<< fromRepo indexFile
+	tmpi <- liftIO . absPath =<< fromRepo indexFileLock
+	liftIO $ copyFile reali tmpi
+
+	d <- fromRepo gitAnnexMergeDir
+	liftIO $ do
+		whenM (doesDirectoryExist d) $
+			removeDirectoryRecursive d
+		createDirectoryIfMissing True d
+
+	withIndexFile tmpi $ do
+		merged <- stageMerge d branch commitmode
+		r <- if merged
+			then return True
+			else resolvemerge
+		mergeDirectCleanup d (fromMaybe Git.Sha.emptyTree oldref)
+		mergeDirectCommit merged startbranch branch commitmode
+
+		liftIO $ rename tmpi reali
+
+		return r
+  where
+	exclusively = withExclusiveLock gitAnnexMergeLock
+
+{- Stage a merge into the index, avoiding changing HEAD or the current
+ - branch. -}
+stageMerge :: FilePath -> Git.Branch -> Git.Branch.CommitMode -> Annex Bool
+stageMerge d branch commitmode = do
+	-- XXX A bug in git makes stageMerge unsafe to use if the git repo
+	-- is configured with core.symlinks=false
+	-- Using mergeNonInteractive is not ideal though, since it will
+	-- update the current branch immediately, before the work tree
+	-- has been updated, which would leave things in an inconsistent
+	-- state if mergeDirectCleanup is interrupted.
+	-- <http://marc.info/?l=git&m=140262402204212&w=2>
+	merger <- ifM (coreSymlinks <$> Annex.getGitConfig)
+		( return Git.Merge.stageMerge
+		, return $ \ref -> Git.Merge.mergeNonInteractive ref commitmode
+		)
+	inRepo $ \g -> do
+		wd <- liftIO $ absPath d
+		gd <- liftIO $ absPath $ Git.localGitDir g
+		merger branch $ 
+			g { location = Local { gitdir = gd, worktree = Just (addTrailingPathSeparator wd) } }
+
+{- Commits after a direct mode merge is complete, and after the work
+ - tree has been updated by mergeDirectCleanup.
+ -}
+mergeDirectCommit :: Bool -> Maybe Git.Ref -> Git.Branch -> Git.Branch.CommitMode -> Annex ()
+mergeDirectCommit allowff old branch commitmode = do
+	void preCommitDirect
+	d <- fromRepo Git.localGitDir
+	let merge_head = d </> "MERGE_HEAD"
+	let merge_msg = d </> "MERGE_MSG"
+	let merge_mode = d </> "MERGE_MODE"
+	ifM (pure allowff <&&> canff)
+		( inRepo $ Git.Branch.update Git.Ref.headRef branch -- fast forward
+		, do
+			msg <- liftIO $
+				catchDefaultIO ("merge " ++ fromRef branch) $
+					readFile merge_msg
+			void $ inRepo $ Git.Branch.commit commitmode False msg
+				Git.Ref.headRef [Git.Ref.headRef, branch]
+		)
+	liftIO $ mapM_ nukeFile [merge_head, merge_msg, merge_mode]
+  where
+	canff = maybe (return False) (\o -> inRepo $ Git.Branch.fastForwardable o branch) old
+
+mergeDirectCleanup :: FilePath -> Git.Ref -> Annex ()
+mergeDirectCleanup d oldref = do
+	updateWorkTree d oldref
+	liftIO $ removeDirectoryRecursive d
+
+{- Updates the direct mode work tree to reflect the changes staged in the
+ - index by a git command, that was run in a temporary work tree.
+ -
+ - Uses diff-index to compare the staged changes with provided ref
+ - which should be the tree before the merge, and applies those
+ - changes to the work tree.
+ -
+ - There are really only two types of changes: An old item can be deleted,
+ - or a new item added. Two passes are made, first deleting and then
+ - adding. This is to handle cases where eg, a file is deleted and a
+ - directory is added. (The diff-tree output may list these in the opposite
+ - order, but we cannot add the directory until the file with the
+ - same name is removed.)
+ -}
+updateWorkTree :: FilePath -> Git.Ref -> Annex ()
+updateWorkTree d oldref = do
+	(items, cleanup) <- inRepo $ DiffTree.diffIndex oldref
+	makeabs <- flip fromTopFilePath <$> gitRepo
+	let fsitems = zip (map (makeabs . DiffTree.file) items) items
+	forM_ fsitems $
+		go makeabs DiffTree.srcsha DiffTree.srcmode moveout moveout_raw
+	forM_ fsitems $
+		go makeabs DiffTree.dstsha DiffTree.dstmode movein movein_raw
+	void $ liftIO cleanup
+  where
+	go makeabs getsha getmode a araw (f, item)
+		| getsha item == nullSha = noop
+		| otherwise = void $
+			tryNonAsync . maybe (araw item makeabs f) (\k -> void $ a item makeabs k f)
+				=<< catKey (getsha item) (getmode item)
+
+	moveout _ _ = removeDirect
+
+	{- Files deleted by the merge are removed from the work tree.
+	 - Empty work tree directories are removed, per git behavior. -}
+	moveout_raw _ _ f = liftIO $ do
+		nukeFile f
+		void $ tryIO $ removeDirectory $ parentDir f
+	
+	{- If the file is already present, with the right content for the
+	 - key, it's left alone. 
+	 -
+	 - If the file is already present, and does not exist in the
+	 - oldref, preserve this local file.
+	 -
+	 - Otherwise, create the symlink and then if possible, replace it
+	 - with the content. -}
+	movein item makeabs k f = unlessM (goodContent k f) $ do
+		preserveUnannexed item makeabs f oldref
+		l <- calcRepo $ gitAnnexLink f k
+		replaceFile f $ makeAnnexLink l
+		toDirect k f
+	
+	{- Any new, modified, or renamed files were written to the temp
+	 - directory by the merge, and are moved to the real work tree. -}
+	movein_raw item makeabs f = do
+		preserveUnannexed item makeabs f oldref
+		liftIO $ do
+			createDirectoryIfMissing True $ parentDir f
+			void $ tryIO $ rename (d </> getTopFilePath (DiffTree.file item)) f
+
+{- If the file that's being moved in is already present in the work
+ - tree, but did not exist in the oldref, preserve this
+ - local, unannexed file (or directory), as "variant-local".
+ -
+ - It's also possible that the file that's being moved in
+ - is in a directory that collides with an exsting, non-annexed
+ - file (not a directory), which should be preserved.
+ -}
+preserveUnannexed :: DiffTree.DiffTreeItem -> (TopFilePath -> FilePath) -> FilePath -> Ref -> Annex ()
+preserveUnannexed item makeabs absf oldref = do
+	whenM (liftIO (collidingitem absf) <&&> unannexed absf) $
+		liftIO $ findnewname absf 0
+	checkdirs (DiffTree.file item)
+  where
+	checkdirs from = case upFrom (getTopFilePath from) of
+		Nothing -> noop
+		Just p -> do
+			let d = asTopFilePath p
+			let absd = makeabs d
+			whenM (liftIO (colliding_nondir absd) <&&> unannexed absd) $
+				liftIO $ findnewname absd 0
+			checkdirs d
+			
+	collidingitem f = isJust
+		<$> catchMaybeIO (getSymbolicLinkStatus f)
+	colliding_nondir f = maybe False (not . isDirectory)
+		<$> catchMaybeIO (getSymbolicLinkStatus f)
+
+	unannexed f = (isNothing <$> isAnnexLink f)
+		<&&> (isNothing <$> catFileDetails oldref f)
+
+	findnewname :: FilePath -> Int -> IO ()
+	findnewname f n = do
+		let localf = mkVariant f 
+			("local" ++ if n > 0 then show n else "")
+		ifM (collidingitem localf)
+			( findnewname f (n+1)
+			, rename f localf
+				`catchIO` const (findnewname f (n+1))
+			)
+
+{- If possible, converts a symlink in the working tree into a direct
+ - mode file. If the content is not available, leaves the symlink
+ - unchanged. -}
+toDirect :: Key -> FilePath -> Annex ()
+toDirect k f = fromMaybe noop =<< toDirectGen k f
+
+toDirectGen :: Key -> FilePath -> Annex (Maybe (Annex ()))
+toDirectGen k f = do
+	loc <- calcRepo $ gitAnnexLocation k
+	ifM (liftIO $ doesFileExist loc)
+		( return $ Just $ fromindirect loc
+		, do
+			{- Copy content from another direct file. -}
+			absf <- liftIO $ absPath f
+			dlocs <- filterM (goodContent k) =<<
+				filterM (\l -> isNothing <$> getAnnexLinkTarget l) =<<
+				(filter (/= absf) <$> addAssociatedFile k f)
+			case dlocs of
+				[] -> return Nothing
+				(dloc:_) -> return $ Just $ fromdirect dloc
+		)
+  where
+	fromindirect loc = do
+		{- Move content from annex to direct file. -}
+		updateInodeCache k loc
+		void $ addAssociatedFile k f
+		modifyContent loc $ do
+			thawContent loc
+			liftIO (replaceFileFrom loc f)
+				`catchIO` (\_ -> freezeContent loc)
+	fromdirect loc = do
+		replaceFile f $
+			liftIO . void . copyFileExternal CopyAllMetaData loc
+		updateInodeCache k f
+
+{- Removes a direct mode file, while retaining its content in the annex
+ - (unless its content has already been changed). -}
+removeDirect :: Key -> FilePath -> Annex ()
+removeDirect k f = do
+	void $ removeAssociatedFileUnchecked k f
+	unlessM (inAnnex k) $
+		ifM (goodContent k f)
+			( moveAnnex k f
+			, logStatus k InfoMissing
+			)
+	liftIO $ do
+		nukeFile f
+		void $ tryIO $ removeDirectory $ parentDir f
+
+{- Called when a direct mode file has been changed. Its old content may be
+ - lost. -}
+changedDirect :: Key -> FilePath -> Annex ()
+changedDirect oldk f = do
+	locs <- removeAssociatedFile oldk f
+	whenM (pure (null locs) <&&> not <$> inAnnex oldk) $
+		logStatus oldk InfoMissing
+
+{- Enable/disable direct mode. -}
+setDirect :: Bool -> Annex ()
+setDirect wantdirect = do
+	if wantdirect
+		then do
+			switchHEAD
+			setbare
+		else do
+			setbare
+			switchHEADBack
+	setConfig (annexConfig "direct") val
+	Annex.changeGitConfig $ \c -> c { annexDirect = wantdirect }
+  where
+	val = Git.Config.boolConfig wantdirect
+	setbare = setConfig (ConfigKey Git.Config.coreBare) val
+
+{- Since direct mode sets core.bare=true, incoming pushes could change
+ - the currently checked out branch. To avoid this problem, HEAD
+ - is changed to a internal ref that nothing is going to push to.
+ -
+ - For refs/heads/master, use refs/heads/annex/direct/master;
+ - this way things that show HEAD (eg shell prompts) will
+ - hopefully show just "master". -}
+directBranch :: Ref -> Ref
+directBranch orighead = case split "/" $ fromRef orighead of
+	("refs":"heads":"annex":"direct":_) -> orighead
+	("refs":"heads":rest) ->
+		Ref $ "refs/heads/annex/direct/" ++ intercalate "/" rest
+	_ -> Ref $ "refs/heads/" ++ fromRef (Git.Ref.base orighead)
+
+{- Converts a directBranch back to the original branch.
+ -
+ - Any other ref is left unchanged.
+ -}
+fromDirectBranch :: Ref -> Ref
+fromDirectBranch directhead = case split "/" $ fromRef directhead of
+	("refs":"heads":"annex":"direct":rest) -> 
+		Ref $ "refs/heads/" ++ intercalate "/" rest
+	_ -> directhead
+
+switchHEAD :: Annex ()
+switchHEAD = maybe noop switch =<< inRepo Git.Branch.currentUnsafe
+  where
+	switch orighead = do
+		let newhead = directBranch orighead
+		maybe noop (inRepo . Git.Branch.update newhead)
+			=<< inRepo (Git.Ref.sha orighead)
+		inRepo $ Git.Branch.checkout newhead
+
+switchHEADBack :: Annex ()
+switchHEADBack = maybe noop switch =<< inRepo Git.Branch.currentUnsafe
+  where
+	switch currhead = do
+		let orighead = fromDirectBranch currhead
+		v <- inRepo $ Git.Ref.sha currhead
+		case v of
+			Just headsha
+				| orighead /= currhead -> do
+					inRepo $ Git.Branch.update orighead headsha
+					inRepo $ Git.Branch.checkout orighead
+					inRepo $ Git.Branch.delete currhead
+			_ -> inRepo $ Git.Branch.checkout orighead

Annex/Direct/Fixup.hs

@@ -0,0 +1,31 @@
+{- git-annex direct mode guard fixup
+ -
+ - Copyright 2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.Direct.Fixup where
+
+import Git.Types
+import Git.Config
+import qualified Git.Construct as Construct
+import Utility.Path
+import Utility.SafeCommand
+
+{- Direct mode repos have core.bare=true, but are not really bare.
+ - Fix up the Repo to be a non-bare repo, and arrange for git commands
+ - run by git-annex to be passed parameters that override this setting. -}
+fixupDirect :: Repo -> IO Repo
+fixupDirect r@(Repo { location = l@(Local { gitdir = d, worktree = Nothing }) }) = do
+	let r' = r
+		{ location = l { worktree = Just (parentDir d) }
+		, gitGlobalOpts = gitGlobalOpts r ++
+			[ Param "-c"
+			, Param $ coreBare ++ "=" ++ boolConfig False
+			]
+		}
+	-- Recalc now that the worktree is correct.
+	rs' <- Construct.fromRemotes r'
+	return $ r' { remotes = rs' }
+fixupDirect r = return r

Annex/Drop.hs

@@ -0,0 +1,123 @@
+{- dropping of unwanted content
+ -
+ - Copyright 2012-2014 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.Drop where
+
+import Common.Annex
+import Logs.Trust
+import Config.NumCopies
+import Types.Remote (uuid)
+import Types.Key (key2file)
+import qualified Remote
+import qualified Command.Drop
+import Command
+import Annex.Wanted
+import Config
+import Annex.Content.Direct
+
+import qualified Data.Set as S
+import System.Log.Logger (debugM)
+
+type Reason = String
+
+{- Drop a key from local and/or remote when allowed by the preferred content
+ - and numcopies settings.
+ -
+ - The UUIDs are ones where the content is believed to be present.
+ - The Remote list can include other remotes that do not have the content;
+ - only ones that match the UUIDs will be dropped from.
+ - If allowed to drop fromhere, that drop will be tried first.
+ -
+ - A remote can be specified that is known to have the key. This can be
+ - used an an optimisation when eg, a key has just been uploaded to a
+ - remote.
+ -
+ - In direct mode, all associated files are checked, and only if all
+ - of them are unwanted are they dropped.
+ -
+ - The runner is used to run commands, and so can be either callCommand
+ - or commandAction.
+ -}
+handleDropsFrom :: [UUID] -> [Remote] -> Reason -> Bool -> Key -> AssociatedFile -> Maybe Remote -> CommandActionRunner -> Annex ()
+handleDropsFrom locs rs reason fromhere key afile knownpresentremote runner = do
+	fs <- ifM isDirect
+		( do
+			l <- associatedFilesRelative key
+			return $ if null l
+				then maybeToList afile
+				else l
+		, return $ maybeToList afile
+		)
+	n <- getcopies fs
+	if fromhere && checkcopies n Nothing
+		then go fs rs =<< dropl fs n
+		else go fs rs n
+  where
+	getcopies fs = do
+		(untrusted, have) <- trustPartition UnTrusted locs
+		numcopies <- if null fs
+			then getNumCopies
+			else maximum <$> mapM getFileNumCopies fs
+		return (NumCopies (length have), numcopies, S.fromList untrusted)
+
+	{- Check that we have enough copies still to drop the content.
+	 - When the remote being dropped from is untrusted, it was not
+	 - counted as a copy, so having only numcopies suffices. Otherwise,
+	 - we need more than numcopies to safely drop. -}
+	checkcopies (have, numcopies, _untrusted) Nothing = have > numcopies
+	checkcopies (have, numcopies, untrusted) (Just u)
+		| S.member u untrusted = have >= numcopies
+		| otherwise = have > numcopies
+	
+	decrcopies (have, numcopies, untrusted) Nothing =
+		(NumCopies (fromNumCopies have - 1), numcopies, untrusted)
+	decrcopies v@(_have, _numcopies, untrusted) (Just u)
+		| S.member u untrusted = v
+		| otherwise = decrcopies v Nothing
+
+	go _ [] _ = noop
+	go fs (r:rest) n
+		| uuid r `S.notMember` slocs = go fs rest n
+		| checkcopies n (Just $ Remote.uuid r) =
+			dropr fs r n >>= go fs rest
+		| otherwise = noop
+
+	checkdrop fs n u a
+		| null fs = check $ -- no associated files; unused content
+			wantDrop True u (Just key) Nothing
+		| otherwise = check $
+			allM (wantDrop True u (Just key) . Just) fs
+		where
+			check c = ifM c
+				( dodrop n u a
+				, return n
+				)
+
+	dodrop n@(have, numcopies, _untrusted) u a = 
+		ifM (safely $ runner $ a numcopies)
+			( do
+				liftIO $ debugM "drop" $ unwords
+					[ "dropped"
+					, fromMaybe (key2file key) afile
+					, "(from " ++ maybe "here" show u ++ ")"
+					, "(copies now " ++ show (fromNumCopies have - 1) ++ ")"
+					, ": " ++ reason
+					]
+				return $ decrcopies n u
+			, return n
+			)
+
+	dropl fs n = checkdrop fs n Nothing $ \numcopies ->
+		Command.Drop.startLocal afile numcopies key knownpresentremote
+
+	dropr fs r n  = checkdrop fs n (Just $ Remote.uuid r) $ \numcopies ->
+		Command.Drop.startRemote afile numcopies key r
+
+	slocs = S.fromList locs
+	
+	safely a = either (const False) id <$> tryNonAsync a
+

Annex/Environment.hs

@@ -0,0 +1,58 @@
+{- git-annex environment
+ -
+ - Copyright 2012, 2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Annex.Environment where
+
+import Common.Annex
+import Utility.UserInfo
+import qualified Git.Config
+import Config
+import Utility.Env
+
+{- Checks that the system's environment allows git to function.
+ - Git requires a GECOS username, or suitable git configuration, or
+ - environment variables.
+ -
+ - Git also requires the system have a hostname containing a dot.
+ - Otherwise, it tries various methods to find a FQDN, and will fail if it
+ - does not. To avoid replicating that code here, which would break if its
+ - methods change, this function does not check the hostname is valid.
+ - Instead, code that commits can use ensureCommit.
+ -}
+checkEnvironment :: Annex ()
+checkEnvironment = do
+	gitusername <- fromRepo $ Git.Config.getMaybe "user.name"
+	when (isNothing gitusername || gitusername == Just "") $
+		liftIO checkEnvironmentIO
+
+checkEnvironmentIO :: IO ()
+checkEnvironmentIO = whenM (isNothing <$> myUserGecos) $ do
+	username <- myUserName
+	ensureEnv "GIT_AUTHOR_NAME" username
+	ensureEnv "GIT_COMMITTER_NAME" username
+  where
+#ifndef __ANDROID__
+	-- existing environment is not overwritten
+	ensureEnv var val = setEnv var val False
+#else
+	-- Environment setting is broken on Android, so this is dealt with
+	-- in runshell instead.
+	ensureEnv _ _ = noop
+#endif
+
+{- Runs an action that commits to the repository, and if it fails, 
+ - sets user.email and user.name to a dummy value and tries the action again. -}
+ensureCommit :: Annex a -> Annex a
+ensureCommit a = either retry return =<< tryNonAsync a 
+  where
+	retry _ = do
+		name <- liftIO myUserName
+		setConfig (ConfigKey "user.name") name
+		setConfig (ConfigKey "user.email") name
+		a

Annex/FileMatcher.hs

@@ -0,0 +1,116 @@
+{- git-annex file matching
+ -
+ - Copyright 2012-2014 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.FileMatcher where
+
+import qualified Data.Map as M
+
+import Common.Annex
+import Limit
+import Utility.Matcher
+import Types.Group
+import Logs.Group
+import Logs.Remote
+import Annex.UUID
+import qualified Annex
+import Types.FileMatcher
+import Git.FilePath
+import Types.Remote (RemoteConfig)
+
+import Data.Either
+import qualified Data.Set as S
+
+checkFileMatcher :: (FileMatcher Annex) -> FilePath -> Annex Bool
+checkFileMatcher matcher file = checkMatcher matcher Nothing (Just file) S.empty True
+
+checkMatcher :: (FileMatcher Annex) -> Maybe Key -> AssociatedFile -> AssumeNotPresent -> Bool -> Annex Bool
+checkMatcher matcher mkey afile notpresent d
+	| isEmpty matcher = return d
+	| otherwise = case (mkey, afile) of
+		(_, Just file) -> go =<< fileMatchInfo file
+		(Just key, _) -> go (MatchingKey key)
+		_ -> return d
+  where
+	go mi = matchMrun matcher $ \a -> a notpresent mi
+
+fileMatchInfo :: FilePath -> Annex MatchInfo
+fileMatchInfo file = do
+	matchfile <- getTopFilePath <$> inRepo (toTopFilePath file)
+	return $ MatchingFile FileInfo
+		{ matchFile = matchfile
+		, currFile = file
+		}
+
+matchAll :: FileMatcher Annex
+matchAll = generate []
+
+parsedToMatcher :: [Either String (Token (MatchFiles Annex))] -> Either String (FileMatcher Annex)
+parsedToMatcher parsed = case partitionEithers parsed of
+	([], vs) -> Right $ generate vs
+	(es, _) -> Left $ unwords $ map ("Parse failure: " ++) es
+
+exprParser :: FileMatcher Annex -> FileMatcher Annex -> GroupMap -> M.Map UUID RemoteConfig -> Maybe UUID -> String -> [Either String (Token (MatchFiles Annex))]
+exprParser matchstandard matchgroupwanted groupmap configmap mu expr =
+	map parse $ tokenizeMatcher expr
+  where
+	parse = parseToken
+		matchstandard
+		matchgroupwanted
+		(limitPresent mu)
+		(limitInDir preferreddir)
+		groupmap
+	preferreddir = fromMaybe "public" $
+		M.lookup "preferreddir" =<< (`M.lookup` configmap) =<< mu
+
+parseToken :: FileMatcher Annex -> FileMatcher Annex -> MkLimit Annex -> MkLimit Annex -> GroupMap -> String -> Either String (Token (MatchFiles Annex))
+parseToken matchstandard matchgroupwanted checkpresent checkpreferreddir groupmap t
+	| t `elem` tokens = Right $ token t
+	| t == "standard" = call matchstandard
+	| t == "groupwanted" = call matchgroupwanted
+	| t == "present" = use checkpresent
+	| t == "inpreferreddir" = use checkpreferreddir
+	| t == "unused" = Right $ Operation limitUnused
+	| otherwise = maybe (Left $ "near " ++ show t) use $ M.lookup k $
+		M.fromList
+			[ ("include", limitInclude)
+			, ("exclude", limitExclude)
+			, ("copies", limitCopies)
+			, ("lackingcopies", limitLackingCopies False)
+			, ("approxlackingcopies", limitLackingCopies True)
+			, ("inbackend", limitInBackend)
+			, ("largerthan", limitSize (>))
+			, ("smallerthan", limitSize (<))
+			, ("metadata", limitMetaData)
+			, ("inallgroup", limitInAllGroup groupmap)
+			]
+  where
+	(k, v) = separate (== '=') t
+	use a = Operation <$> a v
+	call sub = Right $ Operation $ \notpresent mi ->
+		matchMrun sub $ \a -> a notpresent mi
+
+{- This is really dumb tokenization; there's no support for quoted values.
+ - Open and close parens are always treated as standalone tokens;
+ - otherwise tokens must be separated by whitespace. -}
+tokenizeMatcher :: String -> [String]
+tokenizeMatcher = filter (not . null ) . concatMap splitparens . words
+  where
+	splitparens = segmentDelim (`elem` "()")
+
+{- Generates a matcher for files large enough (or meeting other criteria)
+ - to be added to the annex, rather than directly to git. -}
+largeFilesMatcher :: Annex (FileMatcher Annex)
+largeFilesMatcher = go =<< annexLargeFiles <$> Annex.getGitConfig
+  where
+	go Nothing = return matchAll
+	go (Just expr) = do
+		gm <- groupMap
+		rc <- readRemoteLog
+		u <- getUUID
+		either badexpr return $
+			parsedToMatcher $ exprParser matchAll matchAll gm rc (Just u) expr
+	badexpr e = error $ "bad annex.largefiles configuration: " ++ e

Annex/Hook.hs

@@ -0,0 +1,67 @@
+{- git-annex git hooks
+ -
+ - Note that it's important that the scripts installed by git-annex
+ - not change, otherwise removing old hooks using an old version of
+ - the script would fail.
+ -
+ - Copyright 2013-2014 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.Hook where
+
+import Common.Annex
+import qualified Git.Hook as Git
+import Config
+import qualified Annex
+import Utility.Shell
+
+import qualified Data.Map as M
+
+preCommitHook :: Git.Hook
+preCommitHook = Git.Hook "pre-commit" (mkHookScript "git annex pre-commit .")
+
+preCommitAnnexHook :: Git.Hook
+preCommitAnnexHook = Git.Hook "pre-commit-annex" ""
+
+mkHookScript :: String -> String
+mkHookScript s = unlines
+	[ shebang_local
+	, "# automatically configured by git-annex"
+	, s
+	]
+
+hookWrite :: Git.Hook -> Annex ()
+hookWrite h = 
+	-- cannot have git hooks in a crippled filesystem (no execute bit)
+	unlessM crippledFileSystem $
+		unlessM (inRepo $ Git.hookWrite h) $
+			hookWarning h "already exists, not configuring"
+
+hookUnWrite :: Git.Hook -> Annex ()
+hookUnWrite h = unlessM (inRepo $ Git.hookUnWrite h) $
+	hookWarning h "contents modified; not deleting. Edit it to remove call to git annex."
+
+hookWarning :: Git.Hook -> String -> Annex ()
+hookWarning h msg = do
+	r <- gitRepo
+	warning $ Git.hookName h ++ " hook (" ++ Git.hookFile h r ++ ") " ++ msg
+
+{- Runs a hook. To avoid checking if the hook exists every time,
+ - the existing hooks are cached. -}
+runAnnexHook :: Git.Hook -> Annex ()
+runAnnexHook hook = do
+	m <- Annex.getState Annex.existinghooks
+	case M.lookup hook m of
+		Just True -> run
+		Just False -> noop
+		Nothing -> do
+			exists <- inRepo $ Git.hookExists hook
+			Annex.changeState $ \s -> s
+				{ Annex.existinghooks = M.insert hook exists m }
+			when exists run
+  where
+	run = unlessM (inRepo $ Git.runHook hook) $ do
+		h <- fromRepo $ Git.hookFile hook
+		warning $ h ++ " failed"

Annex/Index.hs

@@ -0,0 +1,52 @@
+{- Using other git index files
+ -
+ - Copyright 2014 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Annex.Index (
+	withIndexFile,
+	addGitEnv,
+) where
+
+import qualified Control.Exception as E
+
+import Common.Annex
+import Git.Types
+import qualified Annex
+import Utility.Env
+
+{- Runs an action using a different git index file. -}
+withIndexFile :: FilePath -> Annex a -> Annex a
+withIndexFile f a = do
+	g <- gitRepo
+	g' <- liftIO $ addGitEnv g "GIT_INDEX_FILE" f
+
+	r <- tryNonAsync $ do
+		Annex.changeState $ \s -> s { Annex.repo = g' }
+		a
+	Annex.changeState $ \s -> s { Annex.repo = (Annex.repo s) { gitEnv = gitEnv g} }
+	either E.throw return r
+
+addGitEnv :: Repo -> String -> String -> IO Repo
+addGitEnv g var val = do
+	e <- maybe copyenv return (gitEnv g)
+	let e' = addEntry var val e
+	return $ g { gitEnv = Just e' }
+  where
+	copyenv = do
+#ifdef __ANDROID__
+		{- This should not be necessary on Android, but there is some
+		 - weird getEnvironment breakage. See
+		 - https://github.com/neurocyte/ghc-android/issues/7
+		 - Use getEnv to get some key environment variables that
+		 - git expects to have. -}
+		let keyenv = words "USER PATH GIT_EXEC_PATH HOSTNAME HOME"
+		let getEnvPair k = maybe Nothing (\v -> Just (k, v)) <$> getEnv k
+		liftIO $ catMaybes <$> forM keyenv getEnvPair
+#else
+		liftIO getEnvironment
+#endif

Annex/Init.hs

@@ -0,0 +1,195 @@
+{- git-annex repository initialization
+ -
+ - Copyright 2011 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Annex.Init (
+	ensureInitialized,
+	isInitialized,
+	initialize,
+	initialize',
+	uninitialize,
+	probeCrippledFileSystem,
+) where
+
+import Common.Annex
+import qualified Annex
+import qualified Git
+import qualified Git.LsFiles
+import qualified Git.Config
+import qualified Git.Objects
+import qualified Annex.Branch
+import Logs.UUID
+import Logs.Trust.Basic
+import Types.TrustLevel
+import Annex.Version
+import Annex.Difference
+import Annex.UUID
+import Config
+import Annex.Direct
+import Annex.Content.Direct
+import Annex.Environment
+import Backend
+import Annex.Hook
+import Upgrade
+#ifndef mingw32_HOST_OS
+import Utility.UserInfo
+import Utility.FileMode
+import Annex.Perms
+#endif
+
+genDescription :: Maybe String -> Annex String
+genDescription (Just d) = return d
+genDescription Nothing = do
+	reldir <- liftIO . relHome =<< liftIO . absPath =<< fromRepo Git.repoPath
+	hostname <- fromMaybe "" <$> liftIO getHostname
+#ifndef mingw32_HOST_OS
+	let at = if null hostname then "" else "@"
+	username <- liftIO myUserName
+	return $ concat [username, at, hostname, ":", reldir]
+#else
+	return $ concat [hostname, ":", reldir]
+#endif
+
+initialize :: Maybe String -> Annex ()
+initialize mdescription = do
+	prepUUID
+	initialize'
+
+	u <- getUUID
+	{- This will make the first commit to git, so ensure git is set up
+	 - properly to allow commits when running it. -}
+	ensureCommit $ do
+		Annex.Branch.create
+		describeUUID u =<< genDescription mdescription
+
+-- Everything except for uuid setup.
+initialize' :: Annex ()
+initialize' = do
+	checkFifoSupport
+	checkCrippledFileSystem
+	unlessM isBare $
+		hookWrite preCommitHook
+	setDifferences
+	setVersion supportedVersion
+	ifM (crippledFileSystem <&&> not <$> isBare)
+		( do
+			enableDirectMode
+			setDirect True
+		-- Handle case where this repo was cloned from a
+		-- direct mode repo
+		, unlessM isBare
+			switchHEADBack
+		)
+	createInodeSentinalFile
+	checkSharedClone
+
+uninitialize :: Annex ()
+uninitialize = do
+	hookUnWrite preCommitHook
+	removeRepoUUID
+	removeVersion
+
+{- Will automatically initialize if there is already a git-annex
+ - branch from somewhere. Otherwise, require a manual init
+ - to avoid git-annex accidentially being run in git
+ - repos that did not intend to use it.
+ -
+ - Checks repository version and handles upgrades too.
+ -}
+ensureInitialized :: Annex ()
+ensureInitialized = getVersion >>= maybe needsinit checkUpgrade
+  where
+	needsinit = ifM Annex.Branch.hasSibling
+			( initialize Nothing
+			, error "First run: git-annex init"
+			)
+
+{- Checks if a repository is initialized. Does not check version for ugrade. -}
+isInitialized :: Annex Bool
+isInitialized = maybe Annex.Branch.hasSibling (const $ return True) =<< getVersion
+
+isBare :: Annex Bool
+isBare = fromRepo Git.repoIsLocalBare
+
+{- A crippled filesystem is one that does not allow making symlinks,
+ - or removing write access from files. -}
+probeCrippledFileSystem :: Annex Bool
+probeCrippledFileSystem = do
+#ifdef mingw32_HOST_OS
+	return True
+#else
+	tmp <- fromRepo gitAnnexTmpMiscDir
+	let f = tmp </> "gaprobe"
+	createAnnexDirectory tmp
+	liftIO $ writeFile f ""
+	uncrippled <- liftIO $ probe f
+	liftIO $ removeFile f
+	return $ not uncrippled
+  where
+	probe f = catchBoolIO $ do
+		let f2 = f ++ "2"
+		nukeFile f2
+		createSymbolicLink f f2
+		nukeFile f2
+		preventWrite f
+		allowWrite f
+		return True
+#endif
+
+checkCrippledFileSystem :: Annex ()
+checkCrippledFileSystem = whenM probeCrippledFileSystem $ do
+	warning "Detected a crippled filesystem."
+	setCrippledFileSystem True
+
+	{- Normally git disables core.symlinks itself when the
+	 - filesystem does not support them, but in Cygwin, git
+	 - does support symlinks, while git-annex, not linking
+	 - with Cygwin, does not. -}
+	whenM (coreSymlinks <$> Annex.getGitConfig) $ do
+		warning "Disabling core.symlinks."
+		setConfig (ConfigKey "core.symlinks")
+			(Git.Config.boolConfig False)
+
+probeFifoSupport :: Annex Bool
+probeFifoSupport = do
+#ifdef mingw32_HOST_OS
+	return False
+#else
+	tmp <- fromRepo gitAnnexTmpMiscDir
+	let f = tmp </> "gaprobe"
+	createAnnexDirectory tmp
+	liftIO $ do
+		nukeFile f
+		ms <- tryIO $ do
+			createNamedPipe f ownerReadMode
+			getFileStatus f
+		nukeFile f
+		return $ either (const False) isNamedPipe ms
+#endif
+
+checkFifoSupport :: Annex ()
+checkFifoSupport = unlessM probeFifoSupport $ do
+	warning "Detected a filesystem without fifo support."
+	warning "Disabling ssh connection caching."
+	setConfig (annexConfig "sshcaching") (Git.Config.boolConfig False)
+
+enableDirectMode :: Annex ()
+enableDirectMode = unlessM isDirect $ do
+	warning "Enabling direct mode."
+	top <- fromRepo Git.repoPath
+	(l, clean) <- inRepo $ Git.LsFiles.inRepo [top]
+	forM_ l $ \f ->
+		maybe noop (`toDirect` f) =<< isAnnexLink f
+	void $ liftIO clean
+
+checkSharedClone :: Annex ()
+checkSharedClone = whenM (inRepo Git.Objects.isSharedClone) $ do
+	showSideAction "Repository was cloned with --shared; setting annex.hardlink=true and making repository untrusted."
+	u <- getUUID
+	trustSet u UnTrusted
+	setConfig (annexConfig "hardlink") (Git.Config.boolConfig True)

Annex/Journal.hs

@@ -0,0 +1,120 @@
+{- management of the git-annex journal
+ -
+ - The journal is used to queue up changes before they are committed to the
+ - git-annex branch. Among other things, it ensures that if git-annex is
+ - interrupted, its recorded data is not lost.
+ -
+ - Copyright 2011-2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Annex.Journal where
+
+import Common.Annex
+import qualified Git
+import Annex.Perms
+import Annex.LockFile
+
+{- Records content for a file in the branch to the journal.
+ -
+ - Using the journal, rather than immediatly staging content to the index
+ - avoids git needing to rewrite the index after every change.
+ - 
+ - The file in the journal is updated atomically, which allows
+ - getJournalFileStale to always return a consistent journal file
+ - content, although possibly not the most current one.
+ -}
+setJournalFile :: JournalLocked -> FilePath -> String -> Annex ()
+setJournalFile _jl file content = do
+	tmp <- fromRepo gitAnnexTmpMiscDir
+	createAnnexDirectory =<< fromRepo gitAnnexJournalDir
+	createAnnexDirectory tmp
+	-- journal file is written atomically
+	jfile <- fromRepo $ journalFile file
+	let tmpfile = tmp </> takeFileName jfile
+	liftIO $ do
+		withFile tmpfile WriteMode $ \h -> do
+			fileEncoding h
+#ifdef mingw32_HOST_OS
+			hSetNewlineMode h noNewlineTranslation
+#endif
+			hPutStr h content
+		moveFile tmpfile jfile
+
+{- Gets any journalled content for a file in the branch. -}
+getJournalFile :: JournalLocked -> FilePath -> Annex (Maybe String)
+getJournalFile _jl = getJournalFileStale
+
+{- Without locking, this is not guaranteed to be the most recent
+ - version of the file in the journal, so should not be used as a basis for
+ - changes. -}
+getJournalFileStale :: FilePath -> Annex (Maybe String)
+getJournalFileStale file = inRepo $ \g -> catchMaybeIO $
+	readFileStrictAnyEncoding $ journalFile file g
+
+{- List of files that have updated content in the journal. -}
+getJournalledFiles :: JournalLocked -> Annex [FilePath]
+getJournalledFiles jl = map fileJournal <$> getJournalFiles jl
+
+getJournalledFilesStale :: Annex [FilePath]
+getJournalledFilesStale = map fileJournal <$> getJournalFilesStale
+
+{- List of existing journal files. -}
+getJournalFiles :: JournalLocked -> Annex [FilePath]
+getJournalFiles _jl = getJournalFilesStale
+
+{- List of existing journal files, but without locking, may miss new ones
+ - just being added, or may have false positives if the journal is staged
+ - as it is run. -}
+getJournalFilesStale :: Annex [FilePath]
+getJournalFilesStale = do
+	g <- gitRepo
+	fs <- liftIO $ catchDefaultIO [] $
+		getDirectoryContents $ gitAnnexJournalDir g
+	return $ filter (`notElem` [".", ".."]) fs
+
+withJournalHandle :: (DirectoryHandle -> IO a) -> Annex a
+withJournalHandle a = do
+	d <- fromRepo gitAnnexJournalDir
+	bracketIO (openDirectory d) closeDirectory (liftIO . a)
+
+{- Checks if there are changes in the journal. -}
+journalDirty :: Annex Bool
+journalDirty = do
+	d <- fromRepo gitAnnexJournalDir
+	liftIO $ 
+		(not <$> isDirectoryEmpty d)
+			`catchIO` (const $ doesDirectoryExist d)
+
+{- Produces a filename to use in the journal for a file on the branch.
+ -
+ - The journal typically won't have a lot of files in it, so the hashing
+ - used in the branch is not necessary, and all the files are put directly
+ - in the journal directory.
+ -}
+journalFile :: FilePath -> Git.Repo -> FilePath
+journalFile file repo = gitAnnexJournalDir repo </> concatMap mangle file
+  where
+	mangle c
+		| c == pathSeparator = "_"
+		| c == '_' = "__"
+		| otherwise = [c]
+
+{- Converts a journal file (relative to the journal dir) back to the
+ - filename on the branch. -}
+fileJournal :: FilePath -> FilePath
+fileJournal = replace [pathSeparator, pathSeparator] "_" .
+	replace "_" [pathSeparator]
+
+{- Sentinal value, only produced by lockJournal; required
+ - as a parameter by things that need to ensure the journal is
+ - locked. -}
+data JournalLocked = ProduceJournalLocked
+
+{- Runs an action that modifies the journal, using locking to avoid
+ - contention with other git-annex processes. -}
+lockJournal :: (JournalLocked -> Annex a) -> Annex a
+lockJournal a = withExclusiveLock gitAnnexJournalLock $ a ProduceJournalLocked

Annex/Link.hs

@@ -0,0 +1,112 @@
+{- git-annex links to content
+ -
+ - On file systems that support them, symlinks are used.
+ -
+ - On other filesystems, git instead stores the symlink target in a regular
+ - file.
+ -
+ - Copyright 2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.Link where
+
+import Common.Annex
+import qualified Annex
+import qualified Git.HashObject
+import qualified Git.UpdateIndex
+import qualified Annex.Queue
+import Git.Types
+import Git.FilePath
+
+type LinkTarget = String
+
+{- Checks if a file is a link to a key. -}
+isAnnexLink :: FilePath -> Annex (Maybe Key)
+isAnnexLink file = maybe Nothing (fileKey . takeFileName) <$> getAnnexLinkTarget file
+
+{- Gets the link target of a symlink.
+ -
+ - On a filesystem that does not support symlinks, fall back to getting the
+ - link target by looking inside the file.
+ -
+ - Returns Nothing if the file is not a symlink, or not a link to annex
+ - content.
+ -}
+getAnnexLinkTarget :: FilePath -> Annex (Maybe LinkTarget)
+getAnnexLinkTarget f = getAnnexLinkTarget' f
+	=<< (coreSymlinks <$> Annex.getGitConfig)
+
+{- Pass False to force looking inside file. -}
+getAnnexLinkTarget' :: FilePath -> Bool -> Annex (Maybe LinkTarget)
+getAnnexLinkTarget' file coresymlinks = if coresymlinks
+	then check readSymbolicLink $
+		return Nothing
+	else check readSymbolicLink $
+		check probefilecontent $
+			return Nothing
+  where
+	check getlinktarget fallback = do
+		v <- liftIO $ catchMaybeIO $ getlinktarget file
+		case v of
+			Just l
+				| isLinkToAnnex (fromInternalGitPath l) -> return v
+				| otherwise -> return Nothing
+			Nothing -> fallback
+
+	probefilecontent f = withFile f ReadMode $ \h -> do
+		fileEncoding h
+		-- The first 8k is more than enough to read; link
+		-- files are small.
+		s <- take 8192 <$> hGetContents h
+		-- If we got the full 8k, the file is too large
+		if length s == 8192
+			then return ""
+			else 
+				-- If there are any NUL or newline
+				-- characters, or whitespace, we
+				-- certianly don't have a link to a
+				-- git-annex key.
+				return $ if any (`elem` s) "\0\n\r \t"
+					then ""
+					else s
+
+makeAnnexLink :: LinkTarget -> FilePath -> Annex ()
+makeAnnexLink = makeGitLink
+
+{- Creates a link on disk.
+ -
+ - On a filesystem that does not support symlinks, writes the link target
+ - to a file. Note that git will only treat the file as a symlink if
+ - it's staged as such, so use addAnnexLink when adding a new file or
+ - modified link to git.
+ -}
+makeGitLink :: LinkTarget -> FilePath -> Annex ()
+makeGitLink linktarget file = ifM (coreSymlinks <$> Annex.getGitConfig)
+	( liftIO $ do
+		void $ tryIO $ removeFile file
+		createSymbolicLink linktarget file
+	, liftIO $ writeFile file linktarget
+	)
+
+{- Creates a link on disk, and additionally stages it in git. -}
+addAnnexLink :: LinkTarget -> FilePath -> Annex ()
+addAnnexLink linktarget file = do
+	makeAnnexLink linktarget file
+	stageSymlink file =<< hashSymlink linktarget
+
+{- Injects a symlink target into git, returning its Sha. -}
+hashSymlink :: LinkTarget -> Annex Sha
+hashSymlink linktarget = inRepo $ Git.HashObject.hashObject BlobObject $ 
+	toInternalGitPath linktarget
+
+hashSymlink' :: Git.HashObject.HashObjectHandle -> LinkTarget -> Annex Sha
+hashSymlink' h linktarget = liftIO $ Git.HashObject.hashBlob h $
+	toInternalGitPath linktarget
+
+{- Stages a symlink to the annex, using a Sha of its target. -}
+stageSymlink :: FilePath -> Sha -> Annex ()
+stageSymlink file sha =
+	Annex.Queue.addUpdateIndex =<<
+		inRepo (Git.UpdateIndex.stageSymlink file sha)

Annex/LockFile.hs

@@ -0,0 +1,72 @@
+{- git-annex lock files.
+ -
+ - Copyright 2012, 2014 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Annex.LockFile (
+	lockFileShared,
+	unlockFile,
+	getLockPool,
+	withExclusiveLock,
+) where
+
+import Common.Annex
+import Annex
+import Types.LockPool
+import qualified Git
+import Annex.Perms
+import Utility.LockFile
+
+import qualified Data.Map as M
+
+{- Create a specified lock file, and takes a shared lock, which is retained
+ - in the pool. -}
+lockFileShared :: FilePath -> Annex ()
+lockFileShared file = go =<< fromLockPool file
+  where
+	go (Just _) = noop -- already locked
+	go Nothing = do
+#ifndef mingw32_HOST_OS
+		mode <- annexFileMode
+		lockhandle <- liftIO $ noUmask mode $ lockShared (Just mode) file
+#else
+		lockhandle <- liftIO $ waitToLock $ lockShared file
+#endif
+		changeLockPool $ M.insert file lockhandle
+
+unlockFile :: FilePath -> Annex ()
+unlockFile file = maybe noop go =<< fromLockPool file
+  where
+	go lockhandle = do
+		liftIO $ dropLock lockhandle
+		changeLockPool $ M.delete file
+
+getLockPool :: Annex LockPool
+getLockPool = getState lockpool
+
+fromLockPool :: FilePath -> Annex (Maybe LockHandle)
+fromLockPool file = M.lookup file <$> getLockPool
+
+changeLockPool :: (LockPool -> LockPool) -> Annex ()
+changeLockPool a = do
+	m <- getLockPool
+	changeState $ \s -> s { lockpool = a m }
+
+{- Runs an action with an exclusive lock held. If the lock is already
+ - held, blocks until it becomes free. -}
+withExclusiveLock :: (Git.Repo -> FilePath) -> Annex a -> Annex a
+withExclusiveLock getlockfile a = do
+	lockfile <- fromRepo getlockfile
+	createAnnexDirectory $ takeDirectory lockfile
+	mode <- annexFileMode
+	bracketIO (lock mode lockfile) dropLock (const a)
+  where
+#ifndef mingw32_HOST_OS
+	lock mode = noUmask mode . lockExclusive (Just mode)
+#else
+	lock _mode = waitToLock . lockExclusive
+#endif

Annex/MakeRepo.hs

@@ -0,0 +1,88 @@
+{- making local repositories (used by webapp mostly)
+ -
+ - Copyright 2012-2014 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.MakeRepo where
+
+import Assistant.WebApp.Common
+import Annex.Init
+import qualified Git.Construct
+import qualified Git.Config
+import qualified Git.Command
+import qualified Git.Branch
+import qualified Annex
+import Annex.UUID
+import Annex.Direct
+import Types.StandardGroups
+import Logs.PreferredContent
+import qualified Annex.Branch
+
+{- Makes a new git repository. Or, if a git repository already
+ - exists, returns False. -}
+makeRepo :: FilePath -> Bool -> IO Bool
+makeRepo path bare = ifM (probeRepoExists path)
+	( return False
+	, do
+		(transcript, ok) <-
+			processTranscript "git" (toCommand params) Nothing
+		unless ok $
+			error $ "git init failed!\nOutput:\n" ++ transcript
+		return True
+	)
+  where
+	baseparams = [Param "init", Param "--quiet"]
+	params
+		| bare = baseparams ++ [Param "--bare", File path]
+		| otherwise = baseparams ++ [File path]
+
+{- Runs an action in the git repository in the specified directory. -}
+inDir :: FilePath -> Annex a -> IO a
+inDir dir a = do
+	state <- Annex.new =<< Git.Config.read =<< Git.Construct.fromPath dir
+	Annex.eval state a
+
+{- Creates a new repository, and returns its UUID. -}
+initRepo :: Bool -> Bool -> FilePath -> Maybe String -> Maybe StandardGroup -> IO UUID
+initRepo True primary_assistant_repo dir desc mgroup = inDir dir $ do
+	initRepo' desc mgroup
+	{- Initialize the master branch, so things that expect
+	 - to have it will work, before any files are added. -}
+	unlessM (Git.Config.isBare <$> gitRepo) $
+		void $ inRepo $ Git.Branch.commitCommand Git.Branch.AutomaticCommit
+			[ Param "--quiet"
+			, Param "--allow-empty"
+			, Param "-m"
+			, Param "created repository"
+			]
+	{- Repositories directly managed by the assistant use direct mode.
+	 - 
+	 - Automatic gc is disabled, as it can be slow. Insted, gc is done
+	 - once a day.
+	 -}
+	when primary_assistant_repo $ do
+		setDirect True
+		inRepo $ Git.Command.run
+			[Param "config", Param "gc.auto", Param "0"]
+	getUUID
+{- Repo already exists, could be a non-git-annex repo though so
+ - still initialize it. -}
+initRepo False _ dir desc mgroup = inDir dir $ do
+	initRepo' desc mgroup
+	getUUID
+
+initRepo' :: Maybe String -> Maybe StandardGroup -> Annex ()
+initRepo' desc mgroup = unlessM isInitialized $ do
+	initialize desc
+	u <- getUUID
+	maybe noop (defaultStandardGroup u) mgroup
+	{- Ensure branch gets committed right away so it is
+	 - available for merging immediately. -}
+	Annex.Branch.commit "update"
+
+{- Checks if a git repo exists at a location. -}
+probeRepoExists :: FilePath -> IO Bool
+probeRepoExists dir = isJust <$>
+	catchDefaultIO Nothing (Git.Construct.checkForRepo dir)

Annex/MetaData.hs

@@ -0,0 +1,55 @@
+{- git-annex metadata
+ -
+ - Copyright 2014 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.MetaData (
+	genMetaData,
+	dateMetaData,
+	module X
+) where
+
+import Common.Annex
+import qualified Annex
+import Types.MetaData as X
+import Annex.MetaData.StandardFields as X
+import Logs.MetaData
+import Annex.CatFile
+
+import qualified Data.Set as S
+import qualified Data.Map as M
+import Data.Time.Calendar
+import Data.Time.Clock
+import Data.Time.Clock.POSIX
+
+{- Adds metadata for a file that has just been ingested into the
+ - annex, but has not yet been committed to git.
+ -
+ - When the file has been modified, the metadata is copied over
+ - from the old key to the new key. Note that it looks at the old key as
+ - committed to HEAD -- the new key may or may not have already been staged
+ - in th annex.
+ -
+ - Also, can generate new metadata, if configured to do so.
+ -}
+genMetaData :: Key -> FilePath -> FileStatus -> Annex ()
+genMetaData key file status = do
+	maybe noop (flip copyMetaData key) =<< catKeyFileHEAD file
+	whenM (annexGenMetaData <$> Annex.getGitConfig) $ do
+		curr <- getCurrentMetaData key
+		addMetaData key (dateMetaData mtime curr)
+  where
+	mtime = posixSecondsToUTCTime $ realToFrac $ modificationTime status
+
+{- Generates metadata for a file's date stamp.
+ - Does not overwrite any existing metadata values. -}
+dateMetaData :: UTCTime -> MetaData -> MetaData
+dateMetaData mtime old = MetaData $ M.fromList $ filter isnew
+	[ (yearMetaField, S.singleton $ toMetaValue $ show y)
+	, (monthMetaField, S.singleton $ toMetaValue $ show m)
+	]
+  where
+	isnew (f, _) = S.null (currentMetaDataValues f old)
+	(y, m, _d) = toGregorian $ utctDay $ mtime

Annex/MetaData/StandardFields.hs

@@ -0,0 +1,47 @@
+{- git-annex metadata, standard fields
+ -
+ - Copyright 2014 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.MetaData.StandardFields (
+	tagMetaField,
+	yearMetaField,
+	monthMetaField,
+	lastChangedField,
+	mkLastChangedField,
+	isLastChangedField
+) where
+
+import Types.MetaData
+
+import Data.List
+
+tagMetaField :: MetaField
+tagMetaField = mkMetaFieldUnchecked "tag"
+
+yearMetaField :: MetaField
+yearMetaField = mkMetaFieldUnchecked "year"
+
+monthMetaField :: MetaField
+monthMetaField = mkMetaFieldUnchecked "month"
+
+lastChangedField :: MetaField
+lastChangedField = mkMetaFieldUnchecked lastchanged
+
+mkLastChangedField :: MetaField -> MetaField
+mkLastChangedField f = mkMetaFieldUnchecked (fromMetaField f ++ lastchangedSuffix)
+
+isLastChangedField :: MetaField -> Bool
+isLastChangedField f
+	| f == lastChangedField = True
+	| otherwise = lastchanged `isSuffixOf` s && s /= lastchangedSuffix
+  where
+	s = fromMetaField f
+
+lastchanged :: String
+lastchanged = "lastchanged"
+
+lastchangedSuffix :: String
+lastchangedSuffix = "-lastchanged"

Annex/Notification.hs

@@ -0,0 +1,101 @@
+{- git-annex desktop notifications
+ -
+ - Copyright 2014 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Annex.Notification (NotifyWitness, notifyTransfer, notifyDrop) where
+
+import Common.Annex
+import Logs.Transfer
+#ifdef WITH_DBUS_NOTIFICATIONS
+import qualified Annex
+import Types.DesktopNotify
+import qualified DBus.Notify as Notify
+import qualified DBus.Client
+#endif
+
+-- Witness that notification has happened.
+data NotifyWitness = NotifyWitness
+
+{- Wrap around an action that performs a transfer, which may run multiple
+ - attempts. Displays notification when supported and when the user asked
+ - for it. -}
+notifyTransfer :: Direction -> Maybe FilePath -> (NotifyWitness -> Annex Bool) -> Annex Bool
+notifyTransfer _ Nothing a = a NotifyWitness
+#ifdef WITH_DBUS_NOTIFICATIONS
+notifyTransfer direction (Just f) a = do
+	wanted <- Annex.getState Annex.desktopnotify
+	if (notifyStart wanted || notifyFinish wanted)
+		then do
+			client <- liftIO DBus.Client.connectSession
+			startnotification <- liftIO $ if notifyStart wanted
+				then Just <$> Notify.notify client (startedTransferNote direction f)
+				else pure Nothing
+			ok <- a NotifyWitness
+			when (notifyFinish wanted) $ liftIO $ void $ maybe 
+				(Notify.notify client $ finishedTransferNote ok direction f)
+				(\n -> Notify.replace client n $ finishedTransferNote ok direction f)
+				startnotification
+			return ok
+		else a NotifyWitness
+#else
+notifyTransfer _ (Just _) a = do a NotifyWitness
+#endif
+
+notifyDrop :: Maybe FilePath -> Bool -> Annex ()
+notifyDrop Nothing _ = noop
+#ifdef WITH_DBUS_NOTIFICATIONS
+notifyDrop (Just f) ok = do
+	wanted <- Annex.getState Annex.desktopnotify
+	when (notifyFinish wanted) $ liftIO $ do
+		client <- DBus.Client.connectSession
+		void $ Notify.notify client (droppedNote ok f)
+#else
+notifyDrop (Just _) _ = noop
+#endif
+
+#ifdef WITH_DBUS_NOTIFICATIONS
+startedTransferNote :: Direction -> FilePath -> Notify.Note
+startedTransferNote Upload   = mkNote Notify.Transfer Notify.Low iconUpload
+	"Uploading"
+startedTransferNote Download = mkNote Notify.Transfer Notify.Low iconDownload
+	"Downloading"
+
+finishedTransferNote :: Bool -> Direction -> FilePath -> Notify.Note
+finishedTransferNote False Upload   = mkNote Notify.TransferError Notify.Normal iconFailure
+	"Failed to upload"
+finishedTransferNote False Download = mkNote Notify.TransferError Notify.Normal iconFailure
+	"Failed to download"
+finishedTransferNote True  Upload   = mkNote Notify.TransferComplete Notify.Low iconSuccess
+	"Finished uploading"
+finishedTransferNote True  Download = mkNote Notify.TransferComplete Notify.Low iconSuccess
+	"Finished downloading"
+
+droppedNote :: Bool -> FilePath -> Notify.Note
+droppedNote False = mkNote Notify.TransferError Notify.Normal iconFailure
+	"Failed to drop"
+droppedNote True  = mkNote Notify.TransferComplete Notify.Low iconSuccess
+	"Dropped"
+
+iconUpload, iconDownload, iconFailure, iconSuccess :: String
+iconUpload   = "network-transmit"
+iconDownload = "network-receive"
+iconFailure  = "dialog-error"
+iconSuccess  = "git-annex"  -- Is there a standard icon for success/completion?
+
+mkNote :: Notify.Category -> Notify.UrgencyLevel -> String -> String -> FilePath -> Notify.Note
+mkNote category urgency icon desc path = Notify.blankNote
+	{ Notify.appName = "git-annex"
+	, Notify.appImage = Just (Notify.Icon icon)
+	, Notify.summary = desc ++ " " ++ path
+	, Notify.hints =
+		[ Notify.Category category
+		, Notify.Urgency urgency
+		, Notify.SuppressSound True
+		]
+	}
+#endif

Annex/Path.hs

@@ -0,0 +1,34 @@
+{- git-annex program path
+ -
+ - Copyright 2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Annex.Path where
+
+import Common
+import Config.Files
+import System.Environment
+
+{- A fully qualified path to the currently running git-annex program.
+ - 
+ - getExecutablePath is available since ghc 7.4.2. On OSs it supports
+ - well, it returns the complete path to the program. But, on other OSs,
+ - it might return just the basename.
+ -}
+programPath :: IO (Maybe FilePath)
+programPath = do
+#if MIN_VERSION_base(4,6,0)
+	exe <- getExecutablePath
+	p <- if isAbsolute exe
+		then return exe
+		else readProgramFile
+#else
+	p <- readProgramFile
+#endif
+	-- In case readProgramFile returned just the command name,
+	-- fall back to finding it in PATH.
+	searchPath p

Annex/Perms.hs

@@ -0,0 +1,124 @@
+{- git-annex file permissions
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.Perms (
+	setAnnexFilePerm,
+	setAnnexDirPerm,
+	annexFileMode,
+	createAnnexDirectory,
+	noUmask,
+	createContentDir,
+	freezeContentDir,
+	thawContentDir,
+	modifyContent,
+) where
+
+import Common.Annex
+import Utility.FileMode
+import Git.SharedRepository
+import qualified Annex
+import Config
+
+import System.Posix.Types
+
+withShared :: (SharedRepository -> Annex a) -> Annex a
+withShared a = maybe startup a =<< Annex.getState Annex.shared
+  where
+	startup = do
+		shared <- fromRepo getSharedRepository
+		Annex.changeState $ \s -> s { Annex.shared = Just shared }
+		a shared
+
+setAnnexFilePerm :: FilePath -> Annex ()
+setAnnexFilePerm = setAnnexPerm False
+
+setAnnexDirPerm :: FilePath -> Annex ()
+setAnnexDirPerm = setAnnexPerm True
+
+{- Sets appropriate file mode for a file or directory in the annex,
+ - other than the content files and content directory. Normally,
+ - use the default mode, but with core.sharedRepository set,
+ - allow the group to write, etc. -}
+setAnnexPerm :: Bool -> FilePath -> Annex ()
+setAnnexPerm isdir file = unlessM crippledFileSystem $
+	withShared $ liftIO . go
+  where
+	go GroupShared = modifyFileMode file $ addModes $
+		groupSharedModes ++
+		if isdir then [ ownerExecuteMode, groupExecuteMode ] else []
+	go AllShared = modifyFileMode file $ addModes $
+		readModes ++
+		[ ownerWriteMode, groupWriteMode ] ++
+		if isdir then executeModes else []
+	go _ = noop
+
+{- Gets the appropriate mode to use for creating a file in the annex
+ - (other than content files, which are locked down more). -}
+annexFileMode :: Annex FileMode
+annexFileMode = withShared $ return . go
+  where
+	go GroupShared = sharedmode
+	go AllShared = combineModes (sharedmode:readModes)
+	go _ = stdFileMode
+	sharedmode = combineModes groupSharedModes
+
+{- Creates a directory inside the gitAnnexDir, including any parent
+ - directories. Makes directories with appropriate permissions. -}
+createAnnexDirectory :: FilePath -> Annex ()
+createAnnexDirectory dir = traverse dir [] =<< top
+  where
+	top = parentDir <$> fromRepo gitAnnexDir
+	traverse d below stop
+		| d `equalFilePath` stop = done
+		| otherwise = ifM (liftIO $ doesDirectoryExist d)
+			( done
+			, traverse (parentDir d) (d:below) stop
+			)
+	  where
+		done = forM_ below $ \p -> do
+			liftIO $ createDirectoryIfMissing True p
+			setAnnexDirPerm p
+
+{- Blocks writing to the directory an annexed file is in, to prevent the
+ - file accidentially being deleted. However, if core.sharedRepository
+ - is set, this is not done, since the group must be allowed to delete the
+ - file.
+ -}
+freezeContentDir :: FilePath -> Annex ()
+freezeContentDir file = unlessM crippledFileSystem $
+	liftIO . go =<< fromRepo getSharedRepository
+  where
+	dir = parentDir file
+	go GroupShared = groupWriteRead dir
+	go AllShared = groupWriteRead dir
+	go _ = preventWrite dir
+
+thawContentDir :: FilePath -> Annex ()
+thawContentDir file = unlessM crippledFileSystem $
+	liftIO $ allowWrite $ parentDir file
+
+{- Makes the directory tree to store an annexed file's content,
+ - with appropriate permissions on each level. -}
+createContentDir :: FilePath -> Annex ()
+createContentDir dest = do
+	unlessM (liftIO $ doesDirectoryExist dir) $
+		createAnnexDirectory dir 
+	-- might have already existed with restricted perms
+	unlessM crippledFileSystem $
+		liftIO $ allowWrite dir
+  where
+	dir = parentDir dest
+
+{- Creates the content directory for a file if it doesn't already exist,
+ - or thaws it if it does, then runs an action to modify the file, and
+ - finally, freezes the content directory. -}
+modifyContent :: FilePath -> Annex a -> Annex a
+modifyContent f a = do
+	createContentDir f -- also thaws it
+	v <- tryNonAsync a
+	freezeContentDir f
+	either throwM return v

Annex/Queue.hs

@@ -0,0 +1,62 @@
+{- git-annex command queue
+ -
+ - Copyright 2011, 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.Queue (
+	addCommand,
+	addUpdateIndex,
+	flush,
+	flushWhenFull,
+	size
+) where
+
+import Common.Annex
+import Annex hiding (new)
+import qualified Git.Queue
+import qualified Git.UpdateIndex
+
+{- Adds a git command to the queue. -}
+addCommand :: String -> [CommandParam] -> [FilePath] -> Annex ()
+addCommand command params files = do
+	q <- get
+	store <=< inRepo $ Git.Queue.addCommand command params files q
+
+{- Adds an update-index stream to the queue. -}
+addUpdateIndex :: Git.UpdateIndex.Streamer -> Annex ()
+addUpdateIndex streamer = do
+	q <- get
+	store <=< inRepo $ Git.Queue.addUpdateIndex streamer q
+
+{- Runs the queue if it is full. Should be called periodically. -}
+flushWhenFull :: Annex ()
+flushWhenFull = do
+	q <- get
+	when (Git.Queue.full q) flush
+
+{- Runs (and empties) the queue. -}
+flush :: Annex ()
+flush = do
+	q <- get
+	unless (0 == Git.Queue.size q) $ do
+		showStoringStateAction
+		q' <- inRepo $ Git.Queue.flush q
+		store q'
+
+{- Gets the size of the queue. -}
+size :: Annex Int
+size = Git.Queue.size <$> get
+
+get :: Annex Git.Queue.Queue
+get = maybe new return =<< getState repoqueue
+
+new :: Annex Git.Queue.Queue
+new = do
+	q <- Git.Queue.new . annexQueueSize <$> getGitConfig
+	store q
+	return q
+
+store :: Git.Queue.Queue -> Annex ()
+store q = changeState $ \s -> s { repoqueue = Just q }

Annex/Quvi.hs

@@ -0,0 +1,33 @@
+{- quvi options for git-annex
+ -
+ - Copyright 2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE Rank2Types #-}
+
+module Annex.Quvi where
+
+import Common.Annex
+import qualified Annex
+import Utility.Quvi
+import Utility.Url
+
+withQuviOptions :: forall a. Query a -> [QuviParam] -> URLString -> Annex a
+withQuviOptions a ps url = do
+	v <- quviVersion
+	opts <- map Param . annexQuviOptions <$> Annex.getGitConfig
+	liftIO $ a v (map (\mkp -> mkp v) ps++opts) url
+
+quviSupported :: URLString -> Annex Bool
+quviSupported u = liftIO . flip supported u =<< quviVersion
+
+quviVersion :: Annex QuviVersion
+quviVersion = go =<< Annex.getState Annex.quviversion
+  where
+	go (Just v) = return v
+	go Nothing = do
+		v <- liftIO probeVersion
+		Annex.changeState $ \s -> s { Annex.quviversion = Just v }
+		return v

Annex/ReplaceFile.hs

@@ -0,0 +1,50 @@
+{- git-annex file replacing
+ -
+ - Copyright 2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.ReplaceFile where
+
+import Common.Annex
+import Annex.Perms
+
+{- Replaces a possibly already existing file with a new version, 
+ - atomically, by running an action.
+ - 
+ - The action is passed a temp file, which it can write to, and once
+ - done the temp file is moved into place.
+ -
+ - The action can throw an IO exception, in which case the temp file
+ - will be deleted, and the existing file will be preserved.
+ -
+ - Throws an IO exception when it was unable to replace the file.
+ -}
+replaceFile :: FilePath -> (FilePath -> Annex ()) -> Annex ()
+replaceFile file action = replaceFileOr file action (liftIO . nukeFile)
+
+{- If unable to replace the file with the temp file, runs the
+ - rollback action, which is responsible for cleaning up the temp file. -}
+replaceFileOr :: FilePath -> (FilePath -> Annex ()) -> (FilePath -> Annex ()) -> Annex ()
+replaceFileOr file action rollback = do
+	tmpdir <- fromRepo gitAnnexTmpMiscDir
+	void $ createAnnexDirectory tmpdir
+	tmpfile <- liftIO $ setup tmpdir
+	go tmpfile `catchNonAsync` (const $ rollback tmpfile)
+  where
+	setup tmpdir = do
+		(tmpfile, h) <- openTempFileWithDefaultPermissions tmpdir "tmp"
+		hClose h
+		return tmpfile
+	go tmpfile = do
+		action tmpfile
+		liftIO $ replaceFileFrom tmpfile file
+
+replaceFileFrom :: FilePath -> FilePath -> IO ()
+replaceFileFrom src dest = go `catchIO` fallback
+  where
+	go = moveFile src dest
+	fallback _ = do
+		createDirectoryIfMissing True $ parentDir dest
+		go

Annex/Ssh.hs

@@ -0,0 +1,301 @@
+{- git-annex ssh interface, with connection caching
+ -
+ - Copyright 2012-2015 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Annex.Ssh (
+	sshOptions,
+	sshCacheDir,
+	sshReadPort,
+	forceSshCleanup,
+	sshOptionsEnv,
+	sshOptionsTo,
+	inRepoWithSshOptionsTo,
+	runSshOptions,
+	sshAskPassEnv,
+	runSshAskPass
+) where
+
+import qualified Data.Map as M
+import Data.Hash.MD5
+import System.Exit
+
+import Common.Annex
+import Annex.LockFile
+import qualified Build.SysConfig as SysConfig
+import qualified Annex
+import qualified Git
+import qualified Git.Url
+import Config
+import Config.Files
+import Utility.Env
+import Types.CleanupActions
+import Annex.Index (addGitEnv)
+#ifndef mingw32_HOST_OS
+import Annex.Perms
+import Utility.LockFile
+#endif
+
+{- Generates parameters to ssh to a given host (or user@host) on a given
+ - port. This includes connection caching parameters, and any ssh-options. -}
+sshOptions :: (String, Maybe Integer) -> RemoteGitConfig -> [CommandParam] -> Annex [CommandParam]
+sshOptions (host, port) gc opts = go =<< sshCachingInfo (host, port)
+  where
+	go (Nothing, params) = ret params
+	go (Just socketfile, params) = do
+		prepSocket socketfile
+		ret params
+	ret ps = return $ concat
+		[ ps
+		, map Param (remoteAnnexSshOptions gc)
+		, opts
+		, portParams port
+		, [Param "-T"]
+		]
+
+{- Returns a filename to use for a ssh connection caching socket, and
+ - parameters to enable ssh connection caching. -}
+sshCachingInfo :: (String, Maybe Integer) -> Annex (Maybe FilePath, [CommandParam])
+sshCachingInfo (host, port) = go =<< sshCacheDir
+  where
+	go Nothing = return (Nothing, [])
+	go (Just dir) = do
+		r <- liftIO $ bestSocketPath $ dir </> hostport2socket host port
+		return $ case r of
+			Nothing -> (Nothing, [])
+			Just socketfile -> (Just socketfile, sshConnectionCachingParams socketfile)
+
+{- Given an absolute path to use for a socket file,
+ - returns whichever is shorter of that or the relative path to the same
+ - file.
+ -
+ - If no path can be constructed that is a valid socket, returns Nothing. -}
+bestSocketPath :: FilePath -> IO (Maybe FilePath)
+bestSocketPath abssocketfile = do
+	relsocketfile <- liftIO $ relPathCwdToFile abssocketfile
+	let socketfile = if length abssocketfile <= length relsocketfile
+		then abssocketfile
+		else relsocketfile
+	return $ if valid_unix_socket_path (socketfile ++ sshgarbage)
+			then Just socketfile
+			else Nothing
+  where
+	-- ssh appends a 16 char extension to the socket when setting it
+	-- up, which needs to be taken into account when checking
+	-- that a valid socket was constructed.
+	sshgarbage = replicate (1+16) 'X'
+
+sshConnectionCachingParams :: FilePath -> [CommandParam]
+sshConnectionCachingParams socketfile = 
+	[ Param "-S", Param socketfile
+	, Params "-o ControlMaster=auto -o ControlPersist=yes"
+	]
+
+{- ssh connection caching creates sockets, so will not work on a
+ - crippled filesystem. A GIT_ANNEX_TMP_DIR can be provided to use
+ - a different filesystem. -}
+sshCacheDir :: Annex (Maybe FilePath)
+sshCacheDir
+	| SysConfig.sshconnectioncaching = ifM crippledFileSystem
+		( maybe (return Nothing) usetmpdir =<< gettmpdir
+		, ifM (fromMaybe True . annexSshCaching <$> Annex.getGitConfig)
+			( Just <$> fromRepo gitAnnexSshDir
+			, return Nothing
+			)
+		)
+	| otherwise = return Nothing
+  where
+	gettmpdir = liftIO $ getEnv "GIT_ANNEX_TMP_DIR"
+	usetmpdir tmpdir = liftIO $ catchMaybeIO $ do
+		let socktmp = tmpdir </> "ssh"
+		createDirectoryIfMissing True socktmp
+		return socktmp
+
+portParams :: Maybe Integer -> [CommandParam]
+portParams Nothing = []
+portParams (Just port) = [Param "-p", Param $ show port]
+
+{- Prepare to use a socket file. Locks a lock file to prevent
+ - other git-annex processes from stopping the ssh on this socket. -}
+prepSocket :: FilePath -> Annex ()
+prepSocket socketfile = do
+	-- If the lock pool is empty, this is the first ssh of this
+	-- run. There could be stale ssh connections hanging around
+	-- from a previous git-annex run that was interrupted.
+	whenM (not . any isLock . M.keys <$> getLockPool)
+		sshCleanup
+	-- Cleanup at end of this run.
+	Annex.addCleanup SshCachingCleanup sshCleanup
+
+	liftIO $ createDirectoryIfMissing True $ parentDir socketfile
+	lockFileShared $ socket2lock socketfile
+
+enumSocketFiles :: Annex [FilePath]
+enumSocketFiles = go =<< sshCacheDir
+  where
+	go Nothing = return []
+	go (Just dir) = liftIO $ filter (not . isLock)
+		<$> catchDefaultIO [] (dirContents dir)
+
+{- Stop any unused ssh connection caching processes. -}
+sshCleanup :: Annex ()
+sshCleanup = mapM_ cleanup =<< enumSocketFiles
+  where
+	cleanup socketfile = do
+#ifndef mingw32_HOST_OS
+		-- Drop any shared lock we have, and take an
+		-- exclusive lock, without blocking. If the lock
+		-- succeeds, nothing is using this ssh, and it can
+		-- be stopped.
+		--
+		-- After ssh is stopped cannot remove the lock file;
+		-- other processes may be waiting on our exclusive
+		-- lock to use it.
+		let lockfile = socket2lock socketfile
+		unlockFile lockfile
+		mode <- annexFileMode
+		v <- liftIO $ noUmask mode $ tryLockExclusive (Just mode) lockfile
+		case v of
+			Nothing -> noop
+			Just lck -> do
+				forceStopSsh socketfile
+				liftIO $ dropLock lck
+#else
+		forceStopSsh socketfile
+#endif
+
+{- Stop all ssh connection caching processes, even when they're in use. -}
+forceSshCleanup :: Annex ()
+forceSshCleanup = mapM_ forceStopSsh =<< enumSocketFiles
+
+forceStopSsh :: FilePath -> Annex ()
+forceStopSsh socketfile = do
+	let (dir, base) = splitFileName socketfile
+	let params = sshConnectionCachingParams base
+	-- "ssh -O stop" is noisy on stderr even with -q
+	void $ liftIO $ catchMaybeIO $
+		withQuietOutput createProcessSuccess $
+			(proc "ssh" $ toCommand $
+				[ Params "-O stop"
+				] ++ params ++ [Param "localhost"])
+				{ cwd = Just dir }
+	liftIO $ nukeFile socketfile
+
+{- This needs to be as short as possible, due to limitations on the length
+ - of the path to a socket file. At the same time, it needs to be unique
+ - for each host.
+ -}
+hostport2socket :: String -> Maybe Integer -> FilePath
+hostport2socket host Nothing = hostport2socket' host
+hostport2socket host (Just port) = hostport2socket' $ host ++ "!" ++ show port
+hostport2socket' :: String -> FilePath
+hostport2socket' s
+	| length s > lengthofmd5s = md5s (Str s)
+	| otherwise = s
+  where
+	lengthofmd5s = 32
+
+socket2lock :: FilePath -> FilePath
+socket2lock socket = socket ++ lockExt
+
+isLock :: FilePath -> Bool
+isLock f = lockExt `isSuffixOf` f
+
+lockExt :: String
+lockExt = ".lock"
+
+{- This is the size of the sun_path component of sockaddr_un, which
+ - is the limit to the total length of the filename of a unix socket.
+ -
+ - On Linux, this is 108. On OSX, 104. TODO: Probe
+ -}
+sizeof_sockaddr_un_sun_path :: Int
+sizeof_sockaddr_un_sun_path = 100
+
+{- Note that this looks at the true length of the path in bytes, as it will
+ - appear on disk. -}
+valid_unix_socket_path :: FilePath -> Bool
+valid_unix_socket_path f = length (decodeW8 f) < sizeof_sockaddr_un_sun_path
+
+{- Parses the SSH port, and returns the other OpenSSH options. If
+ - several ports are found, the last one takes precedence. -}
+sshReadPort :: [String] -> (Maybe Integer, [String])
+sshReadPort params = (port, reverse args)
+  where
+	(port,args) = aux (Nothing, []) params
+	aux (p,ps) [] = (p,ps)
+	aux (_,ps) ("-p":p:rest) = aux (readPort p, ps) rest
+	aux (p,ps) (q:rest) | "-p" `isPrefixOf` q = aux (readPort $ drop 2 q, ps) rest
+			    | otherwise = aux (p,q:ps) rest
+	readPort p = fmap fst $ listToMaybe $ reads p
+
+{- When this env var is set, git-annex runs ssh with the specified
+ - options. (The options are separated by newlines.)
+ -
+ - This is a workaround for GIT_SSH not being able to contain
+ - additional parameters to pass to ssh. -}
+sshOptionsEnv :: String
+sshOptionsEnv = "GIT_ANNEX_SSHOPTION"
+
+toSshOptionsEnv :: [CommandParam] -> String
+toSshOptionsEnv = unlines . toCommand
+
+fromSshOptionsEnv :: String -> [CommandParam]
+fromSshOptionsEnv = map Param . lines
+
+{- Enables ssh caching for git push/pull to a particular
+ - remote git repo. (Can safely be used on non-ssh remotes.)
+ -
+ - Also propigates any configured ssh-options.
+ -
+ - Like inRepo, the action is run with the local git repo.
+ - But here it's a modified version, with gitEnv to set GIT_SSH=git-annex,
+ - and sshOptionsEnv set so that git-annex will know what socket
+ - file to use. -}
+inRepoWithSshOptionsTo :: Git.Repo -> RemoteGitConfig -> (Git.Repo -> IO a) -> Annex a
+inRepoWithSshOptionsTo remote gc a =
+	liftIO . a =<< sshOptionsTo remote gc =<< gitRepo
+
+{- To make any git commands be run with ssh caching enabled,
+ - and configured ssh-options alters the local Git.Repo's gitEnv
+ - to set GIT_SSH=git-annex, and sets sshOptionsEnv. -}
+sshOptionsTo :: Git.Repo -> RemoteGitConfig -> Git.Repo -> Annex Git.Repo
+sshOptionsTo remote gc g 
+	| not (Git.repoIsUrl remote) || Git.repoIsHttp remote = uncached
+	| otherwise = case Git.Url.hostuser remote of
+		Nothing -> uncached
+		Just host -> do
+			(msockfile, _) <- sshCachingInfo (host, Git.Url.port remote)
+			case msockfile of
+				Nothing -> return g
+				Just sockfile -> do
+					command <- liftIO readProgramFile
+					prepSocket sockfile
+					let val = toSshOptionsEnv $ concat
+						[ sshConnectionCachingParams sockfile
+						, map Param (remoteAnnexSshOptions gc)
+						]
+					liftIO $ do
+						g' <- addGitEnv g sshOptionsEnv val
+						addGitEnv g' "GIT_SSH" command
+  where
+	uncached = return g
+
+runSshOptions :: [String] -> String -> IO ()
+runSshOptions args s = do
+	let args' = toCommand (fromSshOptionsEnv s) ++ args
+	let p = proc "ssh" args'
+	exitWith =<< waitForProcess . processHandle =<< createProcess p
+
+{- When this env var is set, git-annex is being used as a ssh-askpass
+ - program, and should read the password from the specified location,
+ - and output it for ssh to read. -}
+sshAskPassEnv :: String
+sshAskPassEnv = "GIT_ANNEX_SSHASKPASS"
+
+runSshAskPass :: FilePath -> IO ()
+runSshAskPass passfile = putStrLn =<< readFile passfile

Annex/TaggedPush.hs

@@ -0,0 +1,61 @@
+{- git-annex tagged pushes
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.TaggedPush where
+
+import Common.Annex
+import qualified Remote
+import qualified Annex.Branch
+import qualified Git
+import qualified Git.Ref
+import qualified Git.Command
+import qualified Git.Branch
+import Utility.Base64
+
+{- Converts a git branch into a branch that is tagged with a UUID, typically
+ - the UUID of the repo that will be pushing it, and possibly with other
+ - information.
+ -
+ - Pushing to branches on the remote that have our uuid in them is ugly,
+ - but it reserves those branches for pushing by us, and so our pushes will
+ - never conflict with other pushes.
+ -
+ - To avoid cluttering up the branch display, the branch is put under
+ - refs/synced/, rather than the usual refs/remotes/
+ -
+ - Both UUIDs and Base64 encoded data are always legal to be used in git
+ - refs, per git-check-ref-format.
+ -}
+toTaggedBranch :: UUID -> Maybe String -> Git.Branch -> Git.Branch
+toTaggedBranch u info b = Git.Ref $ intercalate "/" $ catMaybes
+	[ Just "refs/synced"
+	, Just $ fromUUID u
+	, toB64 <$> info
+	, Just $ Git.fromRef $ Git.Ref.base b
+	]
+
+fromTaggedBranch :: Git.Branch -> Maybe (UUID, Maybe String)
+fromTaggedBranch b = case split "/" $ Git.fromRef b of
+	("refs":"synced":u:info:_base) ->
+		Just (toUUID u, fromB64Maybe info)
+	("refs":"synced":u:_base) ->
+		Just (toUUID u, Nothing)
+	_ -> Nothing
+  where
+
+taggedPush :: UUID -> Maybe String -> Git.Ref -> Remote -> Git.Repo -> IO Bool
+taggedPush u info branch remote = Git.Command.runBool
+	[ Param "push"
+	, Param $ Remote.name remote
+	{- Using forcePush here is safe because we "own" the tagged branch
+	 - we're pushing; it has no other writers. Ensures it is pushed
+	 - even if it has been rewritten by a transition. -}
+	, Param $ Git.Branch.forcePush $ refspec Annex.Branch.name
+	, Param $ refspec branch
+	]
+  where
+	refspec b = Git.fromRef b ++ ":" ++ Git.fromRef (toTaggedBranch u info b)

Annex/Transfer.hs

@@ -0,0 +1,145 @@
+{- git-annex transfers
+ -
+ - Copyright 2012-2014 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Annex.Transfer (
+	module X,
+	upload,
+	download,
+	runTransfer,
+	alwaysRunTransfer,
+	noRetry,
+	forwardRetry,
+) where
+
+import Common.Annex
+import Logs.Transfer as X
+import Annex.Notification as X
+import Annex.Perms
+import Utility.Metered
+#ifdef mingw32_HOST_OS
+import Utility.LockFile
+#endif
+
+import Control.Concurrent
+
+upload :: UUID -> Key -> AssociatedFile -> RetryDecider -> (MeterUpdate -> Annex Bool) -> NotifyWitness -> Annex Bool
+upload u key f d a _witness = runTransfer (Transfer Upload u key) f d a
+
+download :: UUID -> Key -> AssociatedFile -> RetryDecider -> (MeterUpdate -> Annex Bool) -> NotifyWitness -> Annex Bool
+download u key f d a _witness = runTransfer (Transfer Download u key) f d a
+
+{- Runs a transfer action. Creates and locks the lock file while the
+ - action is running, and stores info in the transfer information
+ - file.
+ -
+ - If the transfer action returns False, the transfer info is 
+ - left in the failedTransferDir.
+ -
+ - If the transfer is already in progress, returns False.
+ -
+ - An upload can be run from a read-only filesystem, and in this case
+ - no transfer information or lock file is used.
+ -}
+runTransfer :: Transfer -> Maybe FilePath -> RetryDecider -> (MeterUpdate -> Annex Bool) -> Annex Bool
+runTransfer = runTransfer' False
+
+{- Like runTransfer, but ignores any existing transfer lock file for the
+ - transfer, allowing re-running a transfer that is already in progress.
+ -
+ - Note that this may result in confusing progress meter display in the
+ - webapp, if multiple processes are writing to the transfer info file. -}
+alwaysRunTransfer :: Transfer -> Maybe FilePath -> RetryDecider -> (MeterUpdate -> Annex Bool) -> Annex Bool
+alwaysRunTransfer = runTransfer' True
+
+runTransfer' :: Bool -> Transfer -> Maybe FilePath -> RetryDecider -> (MeterUpdate -> Annex Bool) -> Annex Bool
+runTransfer' ignorelock t file shouldretry a = do
+	info <- liftIO $ startTransferInfo file
+	(meter, tfile, metervar) <- mkProgressUpdater t info
+	mode <- annexFileMode
+	(fd, inprogress) <- liftIO $ prep tfile mode info
+	if inprogress && not ignorelock
+		then do
+			showNote "transfer already in progress"
+			return False
+		else do
+			ok <- retry info metervar $
+				bracketIO (return fd) (cleanup tfile) (const $ a meter)
+			unless ok $ recordFailedTransfer t info
+			return ok
+  where
+#ifndef mingw32_HOST_OS
+	prep tfile mode info = do
+		mfd <- catchMaybeIO $
+			openFd (transferLockFile tfile) ReadWrite (Just mode)
+				defaultFileFlags { trunc = True }
+		case mfd of
+			Nothing -> return (Nothing, False)
+			Just fd -> do
+				setFdOption fd CloseOnExec True
+				locked <- catchMaybeIO $
+					setLock fd (WriteLock, AbsoluteSeek, 0, 0)
+				if isNothing locked
+					then do
+						closeFd fd
+						return (Nothing, True)
+					else do
+						void $ tryIO $ writeTransferInfoFile info tfile
+						return (mfd, False)
+#else
+	prep tfile _mode info = do
+		v <- catchMaybeIO $ lockExclusive (transferLockFile tfile)
+		case v of
+			Nothing -> return (Nothing, False)
+			Just Nothing -> return (Nothing, True)
+			Just (Just lockhandle) -> do
+				void $ tryIO $ writeTransferInfoFile info tfile
+				return (Just lockhandle, False)
+#endif
+	cleanup _ Nothing = noop
+	cleanup tfile (Just lockhandle) = do
+		void $ tryIO $ removeFile tfile
+#ifndef mingw32_HOST_OS
+		void $ tryIO $ removeFile $ transferLockFile tfile
+		closeFd lockhandle
+#else
+		{- Windows cannot delete the lockfile until the lock
+		 - is closed. So it's possible to race with another
+		 - process that takes the lock before it's removed,
+		 - so ignore failure to remove.
+		 -}
+		dropLock lockhandle
+		void $ tryIO $ removeFile $ transferLockFile tfile
+#endif
+	retry oldinfo metervar run = do
+		v <- tryNonAsync run
+		case v of
+			Right b -> return b
+			Left e -> do
+				warning (show e)
+				b <- getbytescomplete metervar
+				let newinfo = oldinfo { bytesComplete = Just b }
+				if shouldretry oldinfo newinfo
+					then retry newinfo metervar run
+					else return False
+	getbytescomplete metervar
+		| transferDirection t == Upload =
+			liftIO $ readMVar metervar
+		| otherwise = do
+			f <- fromRepo $ gitAnnexTmpObjectLocation (transferKey t)
+			liftIO $ catchDefaultIO 0 $ getFileSize f
+
+type RetryDecider = TransferInfo -> TransferInfo -> Bool
+
+noRetry :: RetryDecider
+noRetry _ _ = False
+
+{- Retries a transfer when it fails, as long as the failed transfer managed
+ - to send some data. -}
+forwardRetry :: RetryDecider
+forwardRetry old new = bytesComplete old < bytesComplete new

Annex/UUID.hs

@@ -0,0 +1,110 @@
+{- git-annex uuids
+ -
+ - Each git repository used by git-annex has an annex.uuid setting that
+ - uniquely identifies that repository.
+ -
+ - UUIDs of remotes are cached in git config, using keys named
+ - remote.<name>.annex-uuid
+ -
+ - Copyright 2010-2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.UUID (
+	getUUID,
+	getRepoUUID,
+	getUncachedUUID,
+	prepUUID,
+	genUUID,
+	genUUIDInNameSpace,
+	gCryptNameSpace,
+	removeRepoUUID,
+	storeUUID,
+	storeUUIDIn,
+	setUUID,
+	webUUID,
+	bitTorrentUUID,
+) where
+
+import Common.Annex
+import qualified Git
+import qualified Git.Config
+import Config
+
+import qualified Data.UUID as U
+import qualified Data.UUID.V5 as U5
+import System.Random
+import Data.Bits.Utils
+
+configkey :: ConfigKey
+configkey = annexConfig "uuid"
+
+{- Generates a random UUID, that does not include the MAC address. -}
+genUUID :: IO UUID
+genUUID = UUID . show <$> (randomIO :: IO U.UUID)
+
+{- Generates a UUID from a given string, using a namespace.
+ - Given the same namespace, the same string will always result
+ - in the same UUID. -}
+genUUIDInNameSpace :: U.UUID -> String -> UUID
+genUUIDInNameSpace namespace = UUID . show . U5.generateNamed namespace . s2w8
+
+{- Namespace used for UUIDs derived from git-remote-gcrypt ids. -}
+gCryptNameSpace :: U.UUID
+gCryptNameSpace = U5.generateNamed U5.namespaceURL $
+	s2w8 "http://git-annex.branchable.com/design/gcrypt/" 
+
+{- Get current repository's UUID. -}
+getUUID :: Annex UUID
+getUUID = getRepoUUID =<< gitRepo
+
+{- Looks up a repo's UUID, caching it in .git/config if it's not already. -}
+getRepoUUID :: Git.Repo -> Annex UUID
+getRepoUUID r = do
+	c <- toUUID <$> getConfig cachekey ""
+	let u = getUncachedUUID r
+	
+	if c /= u && u /= NoUUID
+		then do
+			updatecache u
+			return u
+		else return c
+  where
+	updatecache u = do
+		g <- gitRepo
+		when (g /= r) $ storeUUIDIn cachekey u
+	cachekey = remoteConfig r "uuid"
+
+removeRepoUUID :: Annex ()
+removeRepoUUID = unsetConfig configkey
+
+getUncachedUUID :: Git.Repo -> UUID
+getUncachedUUID = toUUID . Git.Config.get key ""
+  where
+	(ConfigKey key) = configkey
+
+{- Make sure that the repo has an annex.uuid setting. -}
+prepUUID :: Annex ()
+prepUUID = whenM ((==) NoUUID <$> getUUID) $
+	storeUUID =<< liftIO genUUID
+
+storeUUID :: UUID -> Annex ()
+storeUUID = storeUUIDIn configkey
+
+storeUUIDIn :: ConfigKey -> UUID -> Annex ()
+storeUUIDIn configfield = setConfig configfield . fromUUID
+
+{- Only sets the configkey in the Repo; does not change .git/config -}
+setUUID :: Git.Repo -> UUID -> IO Git.Repo
+setUUID r u = do
+	let s = show configkey ++ "=" ++ fromUUID u
+	Git.Config.store s r
+
+-- Dummy uuid for the whole web. Do not alter.
+webUUID :: UUID
+webUUID = UUID "00000000-0000-0000-0000-000000000001"
+
+-- Dummy uuid for bittorrent. Do not alter.
+bitTorrentUUID :: UUID
+bitTorrentUUID = UUID "00000000-0000-0000-0000-000000000002"

Annex/Url.hs

@@ -0,0 +1,42 @@
+{- Url downloading, with git-annex user agent and configured http
+ - headers and wget/curl options.
+ -
+ - Copyright 2013-2014 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.Url (
+	module U,
+	withUrlOptions,
+	getUrlOptions,
+	getUserAgent,
+) where
+
+import Common.Annex
+import qualified Annex
+import Utility.Url as U
+import qualified Build.SysConfig as SysConfig
+
+defaultUserAgent :: U.UserAgent
+defaultUserAgent = "git-annex/" ++ SysConfig.packageversion
+
+getUserAgent :: Annex (Maybe U.UserAgent)
+getUserAgent = Annex.getState $ 
+	Just . fromMaybe defaultUserAgent . Annex.useragent
+
+getUrlOptions :: Annex U.UrlOptions
+getUrlOptions = mkUrlOptions
+	<$> getUserAgent
+	<*> headers
+	<*> options
+  where
+	headers = do
+		v <- annexHttpHeadersCommand <$> Annex.getGitConfig
+		case v of
+			Just cmd -> lines <$> liftIO (readProcess "sh" ["-c", cmd])
+			Nothing -> annexHttpHeaders <$> Annex.getGitConfig
+	options = map Param . annexWebOptions <$> Annex.getGitConfig
+
+withUrlOptions :: (U.UrlOptions -> IO a) -> Annex a
+withUrlOptions a = liftIO . a =<< getUrlOptions

Annex/VariantFile.hs

@@ -0,0 +1,45 @@
+{- git-annex .variant files for automatic merge conflict resolution
+ -
+ - Copyright 2014 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.VariantFile where
+
+import Common.Annex
+import Types.Key
+
+import Data.Hash.MD5
+
+variantMarker :: String
+variantMarker = ".variant-"
+
+mkVariant :: FilePath -> String -> FilePath
+mkVariant file variant = takeDirectory file
+	</> dropExtension (takeFileName file)
+	++ variantMarker ++ variant
+	++ takeExtension file
+
+{- The filename to use when resolving a conflicted merge of a file,
+ - that points to a key.
+ -
+ - Something derived from the key needs to be included in the filename,
+ - but rather than exposing the whole key to the user, a very weak hash
+ - is used. There is a very real, although still unlikely, chance of
+ - conflicts using this hash.
+ -
+ - In the event that there is a conflict with the filename generated
+ - for some other key, that conflict will itself be handled by the
+ - conflicted merge resolution code. That case is detected, and the full
+ - key is used in the filename.
+ -}
+variantFile :: FilePath -> Key -> FilePath
+variantFile file key
+	| doubleconflict = mkVariant file (key2file key)
+	| otherwise = mkVariant file (shortHash $ key2file key)
+  where
+	doubleconflict = variantMarker `isInfixOf` file
+
+shortHash :: String -> String
+shortHash = take 4 . md5s . md5FilePath

Annex/Version.hs

@@ -0,0 +1,41 @@
+{- git-annex repository versioning
+ -
+ - Copyright 2010,2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Annex.Version where
+
+import Common.Annex
+import Config
+import qualified Annex
+
+type Version = String
+
+supportedVersion :: Version
+supportedVersion = "5"
+
+upgradableVersions :: [Version]
+#ifndef mingw32_HOST_OS
+upgradableVersions = ["0", "1", "2", "4"]
+#else
+upgradableVersions = ["2", "3", "4"]
+#endif
+
+autoUpgradeableVersions :: [Version]
+autoUpgradeableVersions = ["3", "4"]
+
+versionField :: ConfigKey
+versionField = annexConfig "version"
+
+getVersion :: Annex (Maybe Version)
+getVersion = annexVersion <$> Annex.getGitConfig
+
+setVersion :: Version -> Annex ()
+setVersion = setConfig versionField
+
+removeVersion :: Annex ()
+removeVersion = unsetConfig versionField

Annex/View.hs

@@ -0,0 +1,450 @@
+{- metadata based branch views
+ -
+ - Copyright 2014 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.View where
+
+import Common.Annex
+import Annex.View.ViewedFile
+import Types.View
+import Types.MetaData
+import Annex.MetaData
+import qualified Git
+import qualified Git.DiffTree as DiffTree
+import qualified Git.Branch
+import qualified Git.LsFiles
+import qualified Git.Ref
+import Git.UpdateIndex
+import Git.Sha
+import Git.HashObject
+import Git.Types
+import Git.FilePath
+import qualified Backend
+import Annex.Index
+import Annex.Link
+import Annex.CatFile
+import Logs.MetaData
+import Logs.View
+import Utility.Glob
+import Utility.FileMode
+import Types.Command
+import Config
+import CmdLine.Action
+
+import qualified Data.Set as S
+import qualified Data.Map as M
+import "mtl" Control.Monad.Writer
+
+{- Each visible ViewFilter in a view results in another level of
+ - subdirectory nesting. When a file matches multiple ways, it will appear
+ - in multiple subdirectories. This means there is a bit of an exponential
+ - blowup with a single file appearing in a crazy number of places!
+ -
+ - Capping the view size to 5 is reasonable; why wants to dig
+ - through 5+ levels of subdirectories to find anything?
+ -}
+viewTooLarge :: View -> Bool
+viewTooLarge view = visibleViewSize view > 5
+
+visibleViewSize :: View -> Int
+visibleViewSize = length . filter viewVisible . viewComponents
+
+{- Parses field=value, field!=value, tag, and !tag
+ -
+ - Note that the field may not be a legal metadata field name,
+ - but it's let through anyway.
+ - This is useful when matching on directory names with spaces,
+ - which are not legal MetaFields.
+ -}
+parseViewParam :: String -> (MetaField, ViewFilter)
+parseViewParam s = case separate (== '=') s of
+	('!':tag, []) | not (null tag) ->
+		( tagMetaField
+		, mkExcludeValues tag
+		)
+	(tag, []) ->
+		( tagMetaField
+		, mkFilterValues tag
+		)
+	(field, wanted)
+		| end field == "!" ->
+			( mkMetaFieldUnchecked (beginning field)
+			, mkExcludeValues wanted
+			)
+		| otherwise ->
+			( mkMetaFieldUnchecked field
+			, mkFilterValues wanted
+			)
+  where
+	mkFilterValues v
+		| any (`elem` v) "*?" = FilterGlob v
+		| otherwise = FilterValues $ S.singleton $ toMetaValue v
+	mkExcludeValues = ExcludeValues . S.singleton . toMetaValue
+
+data ViewChange = Unchanged | Narrowing | Widening
+	deriving (Ord, Eq, Show)
+
+{- Updates a view, adding new fields to filter on (Narrowing), 
+ - or allowing new values in an existing field (Widening). -}
+refineView :: View -> [(MetaField, ViewFilter)] -> (View, ViewChange)
+refineView origview = checksize . calc Unchanged origview
+  where
+	calc c v [] = (v, c)
+	calc c v ((f, vf):rest) =
+		let (v', c') = refine v f vf
+		in calc (max c c') v' rest
+
+	refine view field vf
+		| field `elem` map viewField (viewComponents view) =
+			let (components', viewchanges) = runWriter $
+				mapM (\c -> updateViewComponent c field vf) (viewComponents view)
+			    viewchange = if field `elem` map viewField (viewComponents origview)
+				then maximum viewchanges
+				else Narrowing
+			in (view { viewComponents = components' }, viewchange)
+		| otherwise = 
+			let component = mkViewComponent field vf
+			    view' = view { viewComponents = component : viewComponents view }
+			in (view', Narrowing)
+	
+	checksize r@(v, _)
+		| viewTooLarge v = error $ "View is too large (" ++ show (visibleViewSize v) ++ " levels of subdirectories)"
+		| otherwise = r
+
+updateViewComponent :: ViewComponent -> MetaField -> ViewFilter -> Writer [ViewChange] ViewComponent
+updateViewComponent c field vf
+	| viewField c == field = do
+		let (newvf, viewchange) = combineViewFilter (viewFilter c) vf
+		tell [viewchange]
+		return $ mkViewComponent field newvf
+	| otherwise = return c
+
+{- Adds an additional filter to a view. This can only result in narrowing
+ - the view. Multivalued filters are added in non-visible form. -}
+filterView :: View -> [(MetaField, ViewFilter)] -> View
+filterView v vs = v { viewComponents = viewComponents f' ++ viewComponents v}
+  where
+	f = fst $ refineView (v {viewComponents = []}) vs
+	f' = f { viewComponents = map toinvisible (viewComponents f) }
+	toinvisible c = c { viewVisible = False }
+
+{- Combine old and new ViewFilters, yielding a result that matches
+ - either old+new, or only new.
+ -
+ - If we have FilterValues and change to a FilterGlob,
+ - it's always a widening change, because the glob could match other
+ - values. OTOH, going the other way, it's a Narrowing change if the old
+ - glob matches all the new FilterValues.
+ -
+ - With two globs, the old one is discarded, and the new one is used.
+ - We can tell if that's a narrowing change by checking if the old
+ - glob matches the new glob. For example, "*" matches "foo*",
+ - so that's narrowing. While "f?o" does not match "f??", so that's
+ - widening.
+ -}
+combineViewFilter :: ViewFilter -> ViewFilter -> (ViewFilter, ViewChange)
+combineViewFilter old@(FilterValues olds) (FilterValues news)
+	| combined == old = (combined, Unchanged)
+	| otherwise = (combined, Widening)
+  where
+	combined = FilterValues (S.union olds news)
+combineViewFilter old@(ExcludeValues olds) (ExcludeValues news)
+	| combined == old = (combined, Unchanged)
+	| otherwise = (combined, Narrowing)
+  where
+	combined = ExcludeValues (S.union olds news)
+combineViewFilter (FilterValues _) newglob@(FilterGlob _) =
+	(newglob, Widening)
+combineViewFilter (FilterGlob oldglob) new@(FilterValues s)
+	| all (matchGlob (compileGlob oldglob CaseInsensative) . fromMetaValue) (S.toList s) = (new, Narrowing)
+	| otherwise = (new, Widening)
+combineViewFilter (FilterGlob old) newglob@(FilterGlob new)
+	| old == new = (newglob, Unchanged)
+	| matchGlob (compileGlob old CaseInsensative) new = (newglob, Narrowing)
+	| otherwise = (newglob, Widening)
+combineViewFilter (FilterGlob _) new@(ExcludeValues _) = (new, Narrowing)
+combineViewFilter (ExcludeValues _) new@(FilterGlob _) = (new, Widening)
+combineViewFilter (FilterValues _) new@(ExcludeValues _) = (new, Narrowing)
+combineViewFilter (ExcludeValues _) new@(FilterValues _) = (new, Widening)
+
+{- Generates views for a file from a branch, based on its metadata
+ - and the filename used in the branch.
+ -
+ - Note that a file may appear multiple times in a view, when it
+ - has multiple matching values for a MetaField used in the View.
+ -
+ - Of course if its MetaData does not match the View, it won't appear at
+ - all.
+ -
+ - Note that for efficiency, it's useful to partially
+ - evaluate this function with the view parameter and reuse
+ - the result. The globs in the view will then be compiled and memoized.
+ -}
+viewedFiles :: View -> MkViewedFile -> FilePath -> MetaData -> [ViewedFile]
+viewedFiles view = 
+	let matchers = map viewComponentMatcher (viewComponents view)
+	in \mkviewedfile file metadata ->
+		let matches = map (\m -> m metadata) matchers
+		in if any isNothing matches
+			then []
+			else 
+				let paths = pathProduct $
+					map (map toViewPath) (visible matches)
+				in if null paths
+					then [mkviewedfile file]
+					else map (</> mkviewedfile file) paths
+  where
+	visible = map (fromJust . snd) .
+		filter (viewVisible . fst) .
+		zip (viewComponents view)
+
+{- Checks if metadata matches a ViewComponent filter, and if so
+ - returns the value, or values that match. Self-memoizing on ViewComponent. -}
+viewComponentMatcher :: ViewComponent -> (MetaData -> Maybe [MetaValue])
+viewComponentMatcher viewcomponent = \metadata -> 
+	matcher (currentMetaDataValues metafield metadata)
+  where
+	metafield = viewField viewcomponent
+	matcher = case viewFilter viewcomponent of
+		FilterValues s -> \values -> setmatches $
+			S.intersection s values
+		FilterGlob glob ->
+			let cglob = compileGlob glob CaseInsensative
+			in \values -> setmatches $
+				S.filter (matchGlob cglob . fromMetaValue) values
+		ExcludeValues excludes -> \values -> 
+			if S.null (S.intersection values excludes)
+				then Just []
+				else Nothing
+	setmatches s
+		| S.null s = Nothing
+		| otherwise = Just (S.toList s)
+
+toViewPath :: MetaValue -> FilePath
+toViewPath = concatMap escapeslash . fromMetaValue
+  where
+	escapeslash c
+		| c == '/' = [pseudoSlash]
+		| c == '\\' = [pseudoBackslash]
+		| c == pseudoSlash = [pseudoSlash, pseudoSlash]
+		| c == pseudoBackslash = [pseudoBackslash, pseudoBackslash]
+		| otherwise = [c]
+
+fromViewPath :: FilePath -> MetaValue
+fromViewPath = toMetaValue . deescapeslash []
+  where
+	deescapeslash s [] = reverse s
+	deescapeslash s (c:cs)
+		| c == pseudoSlash = case cs of
+			(c':cs')
+				| c' == pseudoSlash -> deescapeslash (pseudoSlash:s) cs'
+			_ -> deescapeslash ('/':s) cs
+		| c == pseudoBackslash = case cs of
+			(c':cs')
+				| c' == pseudoBackslash -> deescapeslash (pseudoBackslash:s) cs'
+			_ -> deescapeslash ('/':s) cs
+		| otherwise = deescapeslash (c:s) cs
+
+pseudoSlash :: Char
+pseudoSlash = '\8725' -- '∕' /= '/'
+
+pseudoBackslash :: Char
+pseudoBackslash = '\9586' -- '╲' /= '\'
+
+pathProduct :: [[FilePath]] -> [FilePath]
+pathProduct [] = []
+pathProduct (l:ls) = foldl combinel l ls
+  where
+	combinel xs ys = [combine x y | x <- xs, y <- ys]
+
+{- Extracts the metadata from a ViewedFile, based on the view that was used
+ - to construct it.
+ -
+ - Derived metadata is excluded.
+ -}
+fromView :: View -> ViewedFile -> MetaData
+fromView view f = MetaData $
+	M.fromList (zip fields values) `M.difference` derived
+  where
+	visible = filter viewVisible (viewComponents view)
+	fields = map viewField visible
+	paths = splitDirectories (dropFileName f)
+	values = map (S.singleton . fromViewPath) paths
+	MetaData derived = getViewedFileMetaData f
+
+{- Constructing a view that will match arbitrary metadata, and applying
+ - it to a file yields a set of ViewedFile which all contain the same
+ - MetaFields that were present in the input metadata
+ - (excluding fields that are not visible). -}
+prop_view_roundtrips :: FilePath -> MetaData -> Bool -> Bool
+prop_view_roundtrips f metadata visible = null f || viewTooLarge view ||
+	all hasfields (viewedFiles view viewedFileFromReference f metadata)
+  where
+	view = View (Git.Ref "master") $
+		map (\(mf, mv) -> ViewComponent mf (FilterValues $ S.filter (not . null . fromMetaValue) mv) visible)
+			(fromMetaData metadata)
+	visiblefields = sort (map viewField $ filter viewVisible (viewComponents view))
+	hasfields fv = sort (map fst (fromMetaData (fromView view fv))) == visiblefields
+
+{- A directory foo/bar/baz/ is turned into metadata fields
+ - /=foo, foo/=bar, foo/bar/=baz.
+ -
+ - Note that this may generate MetaFields that legalField rejects.
+ - This is necessary to have a 1:1 mapping between directory names and
+ - fields. So this MetaData cannot safely be serialized. -}
+getDirMetaData :: FilePath -> MetaData
+getDirMetaData d = MetaData $ M.fromList $ zip fields values
+  where
+	dirs = splitDirectories d
+	fields = map (mkMetaFieldUnchecked . addTrailingPathSeparator . joinPath)
+		(inits dirs)
+	values = map (S.singleton . toMetaValue . fromMaybe "" . headMaybe)
+		(tails dirs)
+
+getWorkTreeMetaData :: FilePath -> MetaData
+getWorkTreeMetaData = getDirMetaData . dropFileName
+
+getViewedFileMetaData :: FilePath -> MetaData
+getViewedFileMetaData = getDirMetaData . dirFromViewedFile . takeFileName
+
+{- Applies a view to the currently checked out branch, generating a new
+ - branch for the view.
+ -}
+applyView :: View -> Annex Git.Branch
+applyView view = applyView' viewedFileFromReference getWorkTreeMetaData view
+
+{- Generates a new branch for a View, which must be a more narrow
+ - version of the View originally used to generate the currently
+ - checked out branch. That is, it must match a subset of the files
+ - in view, not any others.
+ -}
+narrowView :: View -> Annex Git.Branch
+narrowView = applyView' viewedFileReuse getViewedFileMetaData
+
+{- Go through each file in the currently checked out branch.
+ - If the file is not annexed, skip it, unless it's a dotfile in the top.
+ - Look up the metadata of annexed files, and generate any ViewedFiles,
+ - and stage them.
+ -
+ - Currently only works in indirect mode. Must be run from top of
+ - repository.
+ -}
+applyView' :: MkViewedFile -> (FilePath -> MetaData) -> View -> Annex Git.Branch
+applyView' mkviewedfile getfilemetadata view = do
+	top <- fromRepo Git.repoPath
+	(l, clean) <- inRepo $ Git.LsFiles.inRepo [top]
+	liftIO . nukeFile =<< fromRepo gitAnnexViewIndex
+	genViewBranch view $ do
+		uh <- inRepo Git.UpdateIndex.startUpdateIndex
+		hasher <- inRepo hashObjectStart
+		forM_ l $ \f -> do
+			relf <- getTopFilePath <$> inRepo (toTopFilePath f)
+			go uh hasher relf =<< Backend.lookupFile f
+		liftIO $ do
+			hashObjectStop hasher
+			void $ stopUpdateIndex uh
+			void clean
+  where
+	genviewedfiles = viewedFiles view mkviewedfile -- enables memoization
+	go uh hasher f (Just k) = do
+		metadata <- getCurrentMetaData k
+		let metadata' = getfilemetadata f `unionMetaData` metadata
+		forM_ (genviewedfiles f metadata') $ \fv -> do
+			f' <- fromRepo $ fromTopFilePath $ asTopFilePath fv
+			stagesymlink uh hasher f' =<< calcRepo (gitAnnexLink f' k)
+	go uh hasher f Nothing
+		| "." `isPrefixOf` f = do
+			s <- liftIO $ getSymbolicLinkStatus f
+			if isSymbolicLink s
+				then stagesymlink uh hasher f =<< liftIO (readSymbolicLink f)
+				else do
+					sha <- liftIO $ Git.HashObject.hashFile hasher f
+					let blobtype = if isExecutable (fileMode s)
+						then ExecutableBlob
+						else FileBlob
+					liftIO . Git.UpdateIndex.streamUpdateIndex' uh
+						=<< inRepo (Git.UpdateIndex.stageFile sha blobtype f)
+		| otherwise = noop
+	stagesymlink uh hasher f linktarget = do
+		sha <- hashSymlink' hasher linktarget
+		liftIO . Git.UpdateIndex.streamUpdateIndex' uh
+			=<< inRepo (Git.UpdateIndex.stageSymlink f sha)
+
+{- Applies a view to the reference branch, generating a new branch
+ - for the View.
+ -
+ - This needs to work incrementally, to quickly update the view branch
+ - when the reference branch is changed. So, it works based on an
+ - old version of the reference branch, uses diffTree to find the
+ - changes, and applies those changes to the view branch.
+ -}
+updateView :: View -> Git.Ref -> Git.Ref -> Annex Git.Branch
+updateView view ref oldref = genViewBranch view $ do
+	(diffs, cleanup) <- inRepo $ DiffTree.diffTree oldref ref
+	forM_ diffs go
+	void $ liftIO cleanup
+  where
+	go diff
+		| DiffTree.dstsha diff == nullSha = error "TODO delete file"
+		| otherwise = error "TODO add file"
+
+{- Diff between currently checked out branch and staged changes, and
+ - update metadata to reflect the changes that are being committed to the
+ - view.
+ -
+ - Adding a file to a directory adds the metadata represented by
+ - that directory to the file, and removing a file from a directory
+ - removes the metadata.
+ -
+ - Note that removes must be handled before adds. This is so
+ - that moving a file from x/foo/ to x/bar/ adds back the metadata for x.
+ -}
+withViewChanges :: (ViewedFile -> Key -> CommandStart) -> (ViewedFile -> Key -> CommandStart) -> Annex ()
+withViewChanges addmeta removemeta = do
+	makeabs <- flip fromTopFilePath <$> gitRepo
+	(diffs, cleanup) <- inRepo $ DiffTree.diffIndex Git.Ref.headRef
+	forM_ diffs handleremovals
+	forM_ diffs (handleadds makeabs)
+	void $ liftIO cleanup
+  where
+	handleremovals item
+		| DiffTree.srcsha item /= nullSha =
+			handlechange item removemeta
+				=<< catKey (DiffTree.srcsha item) (DiffTree.srcmode item)
+		| otherwise = noop
+	handleadds makeabs item
+		| DiffTree.dstsha item /= nullSha = 
+			handlechange item addmeta
+				=<< ifM isDirect
+					( catKey (DiffTree.dstsha item) (DiffTree.dstmode item)
+					-- optimisation
+					, isAnnexLink $ makeabs $ DiffTree.file item
+					)
+		| otherwise = noop
+	handlechange item a = maybe noop
+		(void . commandAction . a (getTopFilePath $ DiffTree.file item))
+
+{- Generates a branch for a view. This is done using a different index
+ - file. An action is run to stage the files that will be in the branch.
+ - Then a commit is made, to the view branch. The view branch is not
+ - checked out, but entering it will display the view. -}
+genViewBranch :: View -> Annex () -> Annex Git.Branch
+genViewBranch view a = withIndex $ do
+	a
+	let branch = branchView view
+	void $ inRepo $ Git.Branch.commit Git.Branch.AutomaticCommit True (fromRef branch) branch []
+	return branch
+
+{- Runs an action using the view index file.
+ - Note that the file does not necessarily exist, or can contain
+ - info staged for an old view. -}
+withIndex :: Annex a -> Annex a
+withIndex a = do
+	f <- fromRepo gitAnnexViewIndex
+	withIndexFile f a
+
+withCurrentView :: (View -> Annex a) -> Annex a
+withCurrentView a = maybe (error "Not in a view.") a =<< currentView

Annex/View/ViewedFile.hs

@@ -0,0 +1,86 @@
+{- filenames (not paths) used in views
+ -
+ - Copyright 2014 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Annex.View.ViewedFile (
+	ViewedFile,
+	MkViewedFile,
+	viewedFileFromReference,
+	viewedFileReuse,
+	dirFromViewedFile,
+	prop_viewedFile_roundtrips,
+) where
+
+import Common.Annex
+
+type FileName = String
+type ViewedFile = FileName
+
+type MkViewedFile = FilePath -> ViewedFile
+
+{- Converts a filepath used in a reference branch to the
+ - filename that will be used in the view.
+ -
+ - No two filepaths from the same branch should yeild the same result,
+ - so all directory structure needs to be included in the output filename
+ - in some way.
+ -
+ - So, from dir/subdir/file.foo, generate file_%dir%subdir%.foo
+ -}
+viewedFileFromReference :: MkViewedFile
+viewedFileFromReference f = concat
+	[ escape base
+	, if null dirs then "" else "_%" ++ intercalate "%" (map escape dirs) ++ "%"
+	, escape $ concat extensions
+	]
+  where
+	(path, basefile) = splitFileName f
+	dirs = filter (/= ".") $ map dropTrailingPathSeparator (splitPath path)
+	(base, extensions) = splitShortExtensions basefile
+
+	{- To avoid collisions with filenames or directories that contain
+	 - '%', and to allow the original directories to be extracted
+	 - from the ViewedFile, '%' is escaped. )
+	 -}
+	escape :: String -> String
+	escape = replace "%" (escchar:'%':[]) . replace [escchar] [escchar, escchar]
+
+escchar :: Char
+#ifndef mingw32_HOST_OS
+escchar = '\\'
+#else
+-- \ is path separator on Windows, so instead use !
+escchar = '!'
+#endif
+
+{- For use when operating already within a view, so whatever filepath
+ - is present in the work tree is already a ViewedFile. -}
+viewedFileReuse :: MkViewedFile
+viewedFileReuse = takeFileName
+
+{- Extracts from a ViewedFile the directory where the file is located on
+ - in the reference branch. -}
+dirFromViewedFile :: ViewedFile -> FilePath
+dirFromViewedFile = joinPath . drop 1 . sep [] ""
+  where
+	sep l _ [] = reverse l
+	sep l curr (c:cs)
+		| c == '%' = sep (reverse curr:l) "" cs
+		| c == escchar = case cs of
+			(c':cs') -> sep l (c':curr) cs'
+			[] -> sep l curr cs
+		| otherwise = sep l (c:curr) cs
+
+prop_viewedFile_roundtrips :: FilePath -> Bool
+prop_viewedFile_roundtrips f
+	-- Relative filenames wanted, not directories.
+	| any (isPathSeparator) (end f ++ beginning f) = True
+	| isAbsolute f = True
+	| otherwise = dir == dirFromViewedFile (viewedFileFromReference f)
+  where
+	dir = joinPath $ beginning $ splitDirectories f

Annex/Wanted.hs

@@ -0,0 +1,29 @@
+{- git-annex checking whether content is wanted
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Annex.Wanted where
+
+import Common.Annex
+import Logs.PreferredContent
+import Annex.UUID
+
+import qualified Data.Set as S
+
+{- Check if a file is preferred content for the local repository. -}
+wantGet :: Bool -> Maybe Key -> AssociatedFile -> Annex Bool
+wantGet d key file = isPreferredContent Nothing S.empty key file d
+
+{- Check if a file is preferred content for a remote. -}
+wantSend :: Bool -> Maybe Key -> AssociatedFile -> UUID -> Annex Bool
+wantSend d key file to = isPreferredContent (Just to) S.empty key file d
+
+{- Check if a file can be dropped, maybe from a remote.
+ - Don't drop files that are preferred content. -}
+wantDrop :: Bool -> Maybe UUID -> Maybe Key -> AssociatedFile -> Annex Bool
+wantDrop d from key file = do
+	u <- maybe getUUID (return . id) from
+	not <$> isPreferredContent (Just u) (S.singleton u) key file d

Assistant.hs

@@ -0,0 +1,197 @@
+{- git-annex assistant daemon
+ -
+ - Copyright 2012-2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Assistant where
+
+import qualified Annex
+import Assistant.Common
+import Assistant.DaemonStatus
+import Assistant.NamedThread
+import Assistant.Types.ThreadedMonad
+import Assistant.Threads.DaemonStatus
+import Assistant.Threads.Watcher
+import Assistant.Threads.Committer
+import Assistant.Threads.Pusher
+import Assistant.Threads.Merger
+import Assistant.Threads.TransferWatcher
+import Assistant.Threads.Transferrer
+import Assistant.Threads.RemoteControl
+import Assistant.Threads.SanityChecker
+import Assistant.Threads.Cronner
+import Assistant.Threads.ProblemFixer
+#ifdef WITH_CLIBS
+import Assistant.Threads.MountWatcher
+#endif
+import Assistant.Threads.NetWatcher
+import Assistant.Threads.Upgrader
+import Assistant.Threads.UpgradeWatcher
+import Assistant.Threads.TransferScanner
+import Assistant.Threads.TransferPoller
+import Assistant.Threads.ConfigMonitor
+import Assistant.Threads.Glacier
+#ifdef WITH_WEBAPP
+import Assistant.WebApp
+import Assistant.Threads.WebApp
+#ifdef WITH_PAIRING
+import Assistant.Threads.PairListener
+#endif
+#ifdef WITH_XMPP
+import Assistant.Threads.XMPPClient
+import Assistant.Threads.XMPPPusher
+#endif
+#else
+import Assistant.Types.UrlRenderer
+#endif
+import qualified Utility.Daemon
+import Utility.ThreadScheduler
+import Utility.HumanTime
+import qualified Build.SysConfig as SysConfig
+import Annex.Perms
+import Utility.LogFile
+#ifdef mingw32_HOST_OS
+import Utility.Env
+import Config.Files
+import System.Environment (getArgs)
+#endif
+
+import System.Log.Logger
+import Network.Socket (HostName)
+
+stopDaemon :: Annex ()
+stopDaemon = liftIO . Utility.Daemon.stopDaemon =<< fromRepo gitAnnexPidFile
+
+{- Starts the daemon. If the daemon is run in the foreground, once it's
+ - running, can start the browser.
+ -
+ - startbrowser is passed the url and html shim file, as well as the original
+ - stdout and stderr descriptors. -}
+startDaemon :: Bool -> Bool -> Maybe Duration -> Maybe String -> Maybe HostName ->  Maybe (Maybe Handle -> Maybe Handle -> String -> FilePath -> IO ()) -> Annex ()
+startDaemon assistant foreground startdelay cannotrun listenhost startbrowser = do
+	
+	Annex.changeState $ \s -> s { Annex.daemon = True }
+	pidfile <- fromRepo gitAnnexPidFile
+	logfile <- fromRepo gitAnnexLogFile
+	liftIO $ debugM desc $ "logging to " ++ logfile
+#ifndef mingw32_HOST_OS
+	createAnnexDirectory (parentDir logfile)
+	logfd <- liftIO $ handleToFd =<< openLog logfile
+	if foreground
+		then do
+			origout <- liftIO $ catchMaybeIO $ 
+				fdToHandle =<< dup stdOutput
+			origerr <- liftIO $ catchMaybeIO $ 
+				fdToHandle =<< dup stdError
+			let undaemonize = Utility.Daemon.foreground logfd (Just pidfile)
+			start undaemonize $ 
+				case startbrowser of
+					Nothing -> Nothing
+					Just a -> Just $ a origout origerr
+		else
+			start (Utility.Daemon.daemonize logfd (Just pidfile) False) Nothing
+#else
+	-- Windows doesn't daemonize, but does redirect output to the
+	-- log file. The only way to do so is to restart the program.
+	when (foreground || not foreground) $ do
+		let flag = "GIT_ANNEX_OUTPUT_REDIR"
+		createAnnexDirectory (parentDir logfile)
+		ifM (liftIO $ isNothing <$> getEnv flag)
+			( liftIO $ withFile devNull WriteMode $ \nullh -> do
+				loghandle <- openLog logfile
+				e <- getEnvironment
+				cmd <- readProgramFile
+				ps <- getArgs
+				(_, _, _, pid) <- createProcess (proc cmd ps)
+					{ env = Just (addEntry flag "1" e)
+					, std_in = UseHandle nullh
+					, std_out = UseHandle loghandle
+					, std_err = UseHandle loghandle
+					}
+				exitWith =<< waitForProcess pid
+			, start (Utility.Daemon.foreground (Just pidfile)) $
+				case startbrowser of
+					Nothing -> Nothing
+					Just a -> Just $ a Nothing Nothing
+			)
+#endif
+  where
+	desc
+		| assistant = "assistant"
+		| otherwise = "watch"
+	start daemonize webappwaiter = withThreadState $ \st -> do
+		checkCanWatch
+		dstatus <- startDaemonStatus
+		logfile <- fromRepo gitAnnexLogFile
+		liftIO $ debugM desc $ "logging to " ++ logfile
+		liftIO $ daemonize $
+			flip runAssistant (go webappwaiter) 
+				=<< newAssistantData st dstatus
+
+#ifdef WITH_WEBAPP
+	go webappwaiter = do
+		d <- getAssistant id
+#else
+	go _webappwaiter = do
+#endif
+		notice ["starting", desc, "version", SysConfig.packageversion]
+		urlrenderer <- liftIO newUrlRenderer
+#ifdef WITH_WEBAPP
+		let webappthread = [ assist $ webAppThread d urlrenderer False cannotrun Nothing listenhost webappwaiter ]
+#else
+		let webappthread = []
+#endif
+		let threads = if isJust cannotrun
+			then webappthread
+			else webappthread ++
+				[ watch commitThread
+#ifdef WITH_WEBAPP
+#ifdef WITH_PAIRING
+				, assist $ pairListenerThread urlrenderer
+#endif
+#ifdef WITH_XMPP
+				, assist $ xmppClientThread urlrenderer
+				, assist $ xmppSendPackThread urlrenderer
+				, assist $ xmppReceivePackThread urlrenderer
+#endif
+#endif
+				, assist pushThread
+				, assist pushRetryThread
+				, assist mergeThread
+				, assist transferWatcherThread
+				, assist transferPollerThread
+				, assist transfererThread
+				, assist remoteControlThread
+				, assist daemonStatusThread
+				, assist $ sanityCheckerDailyThread urlrenderer
+				, assist sanityCheckerHourlyThread
+				, assist $ problemFixerThread urlrenderer
+#ifdef WITH_CLIBS
+				, assist $ mountWatcherThread urlrenderer
+#endif
+				, assist netWatcherThread
+				, assist $ upgraderThread urlrenderer
+				, assist $ upgradeWatcherThread urlrenderer
+				, assist netWatcherFallbackThread
+				, assist $ transferScannerThread urlrenderer
+				, assist $ cronnerThread urlrenderer
+				, assist configMonitorThread
+				, assist glacierThread
+				, watch watchThread
+				-- must come last so that all threads that wait
+				-- on it have already started waiting
+				, watch $ sanityCheckerStartupThread startdelay
+				]
+	
+		mapM_ (startthread urlrenderer) threads
+		liftIO waitForTermination
+
+	watch a = (True, a)
+	assist a = (False, a)
+	startthread urlrenderer (watcher, t)
+		| watcher || assistant = startNamedThread urlrenderer t
+		| otherwise = noop

Assistant/Alert.hs

@@ -0,0 +1,461 @@
+{- git-annex assistant alerts
+ -
+ - Copyright 2012-2014 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE OverloadedStrings, CPP, BangPatterns #-}
+
+module Assistant.Alert where
+
+import Common.Annex
+import Assistant.Types.Alert
+import Assistant.Alert.Utility
+import qualified Remote
+import Utility.Tense
+import Logs.Transfer
+import Types.Distribution
+import Git.Types (RemoteName)
+
+import Data.String
+import qualified Data.Text as T
+import qualified Control.Exception as E
+
+#ifdef WITH_WEBAPP
+import Assistant.DaemonStatus
+import Assistant.WebApp.Types
+import Assistant.WebApp (renderUrl)
+import Yesod
+#endif
+import Assistant.Monad
+import Assistant.Types.UrlRenderer
+
+{- Makes a button for an alert that opens a Route. 
+ -
+ - If autoclose is set, the button will close the alert it's
+ - attached to when clicked. -}
+#ifdef WITH_WEBAPP
+mkAlertButton :: Bool -> T.Text -> UrlRenderer -> Route WebApp -> Assistant AlertButton
+mkAlertButton autoclose label urlrenderer route = do
+	close <- asIO1 removeAlert
+	url <- liftIO $ renderUrl urlrenderer route []
+	return $ AlertButton
+		{ buttonLabel = label
+		, buttonUrl = url
+		, buttonAction = if autoclose then Just close else Nothing
+		, buttonPrimary = True
+		}
+#endif
+
+renderData :: Alert -> TenseText
+renderData = tenseWords . alertData
+
+baseActivityAlert :: Alert
+baseActivityAlert = Alert
+	{ alertClass = Activity
+	, alertHeader = Nothing
+	, alertMessageRender = renderData
+	, alertData = []
+	, alertCounter = 0
+	, alertBlockDisplay = False
+	, alertClosable = False
+	, alertPriority = Medium
+	, alertIcon = Just ActivityIcon
+	, alertCombiner = Nothing
+	, alertName = Nothing
+	, alertButtons = []
+	}
+
+warningAlert :: String -> String -> Alert
+warningAlert name msg = Alert
+	{ alertClass = Warning
+	, alertHeader = Just $ tenseWords ["warning"]
+	, alertMessageRender = renderData
+	, alertData = [UnTensed $ T.pack msg]
+	, alertCounter = 0
+	, alertBlockDisplay = True
+	, alertClosable = True
+	, alertPriority = High
+	, alertIcon = Just ErrorIcon
+	, alertCombiner = Just $ dataCombiner $ \_old new -> new
+	, alertName = Just $ WarningAlert name
+	, alertButtons = []
+	}
+
+errorAlert :: String -> [AlertButton] -> Alert
+errorAlert msg buttons = Alert
+	{ alertClass = Error
+	, alertHeader = Nothing
+	, alertMessageRender = renderData
+	, alertData = [UnTensed $ T.pack msg]
+	, alertCounter = 0
+	, alertBlockDisplay = True
+	, alertClosable = True
+	, alertPriority = Pinned
+	, alertIcon = Just ErrorIcon
+	, alertCombiner = Nothing
+	, alertName = Nothing
+	, alertButtons = buttons
+	}
+
+activityAlert :: Maybe TenseText -> [TenseChunk] -> Alert
+activityAlert header dat = baseActivityAlert
+	{ alertHeader = header
+	, alertData = dat
+	}
+
+startupScanAlert :: Alert
+startupScanAlert = activityAlert Nothing
+	[Tensed "Performing" "Performed", "startup scan"]
+
+{- Displayed when a shutdown is occurring, so will be seen after shutdown
+ - has happened. -}
+shutdownAlert :: Alert
+shutdownAlert = warningAlert "shutdown" "git-annex has been shut down"
+
+commitAlert :: Alert
+commitAlert = activityAlert Nothing
+	[Tensed "Committing" "Committed", "changes to git"]
+
+showRemotes :: [RemoteName] -> TenseChunk
+showRemotes = UnTensed . T.intercalate ", " . map T.pack
+
+syncAlert :: [Remote] -> Alert
+syncAlert = syncAlert' . map Remote.name
+
+syncAlert' :: [RemoteName] -> Alert
+syncAlert' rs = baseActivityAlert
+	{ alertName = Just SyncAlert
+	, alertHeader = Just $ tenseWords
+		[Tensed "Syncing" "Synced", "with", showRemotes rs]
+	, alertPriority = Low
+	, alertIcon = Just SyncIcon
+	}
+
+syncResultAlert :: [Remote] -> [Remote] -> Alert
+syncResultAlert succeeded failed = syncResultAlert'
+	(map Remote.name succeeded)
+	(map Remote.name failed)
+
+syncResultAlert' :: [RemoteName] -> [RemoteName] -> Alert
+syncResultAlert' succeeded failed = makeAlertFiller (not $ null succeeded) $
+	baseActivityAlert
+		{ alertName = Just SyncAlert
+		, alertHeader = Just $ tenseWords msg
+		}
+  where
+	msg
+		| null succeeded = ["Failed to sync with", showRemotes failed]
+		| null failed = ["Synced with", showRemotes succeeded]
+		| otherwise =
+			[ "Synced with", showRemotes succeeded
+			, "but not with", showRemotes failed
+			]
+
+sanityCheckAlert :: Alert
+sanityCheckAlert = activityAlert
+	(Just $ tenseWords [Tensed "Running" "Ran", "daily sanity check"])
+	["to make sure everything is ok."]
+
+sanityCheckFixAlert :: String -> Alert
+sanityCheckFixAlert msg = Alert
+	{ alertClass = Warning
+	, alertHeader = Just $ tenseWords ["Fixed a problem"]
+	, alertMessageRender = render
+	, alertData = [UnTensed $ T.pack msg]
+	, alertCounter = 0
+	, alertBlockDisplay = True
+	, alertPriority = High
+	, alertClosable = True
+	, alertIcon = Just ErrorIcon
+	, alertName = Just SanityCheckFixAlert
+	, alertCombiner = Just $ dataCombiner (++)
+	, alertButtons = []
+	}
+  where
+	render alert = tenseWords $ alerthead : alertData alert ++ [alertfoot]
+	alerthead = "The daily sanity check found and fixed a problem:"
+	alertfoot = "If these problems persist, consider filing a bug report."
+
+fsckingAlert :: AlertButton -> Maybe Remote -> Alert
+fsckingAlert button mr = baseActivityAlert
+	{ alertData = case mr of
+		Nothing -> [ UnTensed $ T.pack $ "Consistency check in progress" ]
+		Just r -> [ UnTensed $ T.pack $ "Consistency check of " ++ Remote.name r ++ " in progress"]
+	, alertButtons = [button]
+	}
+
+showFscking :: UrlRenderer -> Maybe Remote -> IO (Either E.SomeException a) -> Assistant a
+showFscking urlrenderer mr a = do
+#ifdef WITH_WEBAPP
+	button <- mkAlertButton False (T.pack "Configure") urlrenderer ConfigFsckR
+	r <- alertDuring (fsckingAlert button mr) $
+		liftIO a
+#else
+	r <- liftIO a
+#endif
+	either (liftIO . E.throwIO) return r
+
+notFsckedNudge :: UrlRenderer -> Maybe Remote -> Assistant ()
+#ifdef WITH_WEBAPP
+notFsckedNudge urlrenderer mr = do
+	button <- mkAlertButton True (T.pack "Configure") urlrenderer ConfigFsckR
+	void $ addAlert (notFsckedAlert mr button)
+#else
+notFsckedNudge _ _ = noop
+#endif
+
+notFsckedAlert :: Maybe Remote -> AlertButton -> Alert
+notFsckedAlert mr button = Alert
+	{ alertHeader = Just $ fromString $ concat
+		[ "You should enable consistency checking to protect your data"
+		, maybe "" (\r -> " in " ++ Remote.name r) mr
+		, "."
+		]
+	, alertIcon = Just InfoIcon
+	, alertPriority = High
+	, alertButtons = [button]
+	, alertClosable = True
+	, alertClass = Message
+	, alertMessageRender = renderData
+	, alertCounter = 0
+	, alertBlockDisplay = True
+	, alertName = Just NotFsckedAlert
+	, alertCombiner = Just $ dataCombiner $ \_old new -> new
+	, alertData = []
+	}
+
+baseUpgradeAlert :: [AlertButton] -> TenseText -> Alert
+baseUpgradeAlert buttons message = Alert
+	{ alertHeader = Just message
+	, alertIcon = Just UpgradeIcon
+	, alertPriority = High
+	, alertButtons = buttons
+	, alertClosable = True
+	, alertClass = Message
+	, alertMessageRender = renderData
+	, alertCounter = 0
+	, alertBlockDisplay = True
+	, alertName = Just UpgradeAlert
+	, alertCombiner = Just $ fullCombiner $ \new _old -> new
+	, alertData = []
+	}
+
+canUpgradeAlert :: AlertPriority -> GitAnnexVersion -> AlertButton -> Alert
+canUpgradeAlert priority version button = 
+	(baseUpgradeAlert [button] $ fromString msg)
+		{ alertPriority = priority
+		, alertData = [fromString $ " (version " ++ version ++ ")"]
+		}
+  where
+	msg = if priority >= High
+		then "An important upgrade of git-annex is available!"
+		else "An upgrade of git-annex is available."
+
+upgradeReadyAlert :: AlertButton -> Alert
+upgradeReadyAlert button = baseUpgradeAlert [button] $
+	fromString "A new version of git-annex has been installed."
+
+upgradingAlert :: Alert
+upgradingAlert = activityAlert Nothing [ fromString "Upgrading git-annex" ]
+
+upgradeFinishedAlert :: Maybe AlertButton -> GitAnnexVersion -> Alert
+upgradeFinishedAlert button version =
+	baseUpgradeAlert (maybeToList button) $ fromString $ 
+		"Finished upgrading git-annex to version " ++ version
+
+upgradeFailedAlert :: String -> Alert
+upgradeFailedAlert msg = (errorAlert msg [])
+	{ alertHeader = Just $ fromString "Upgrade failed." }
+
+unusedFilesAlert :: [AlertButton] -> String -> Alert
+unusedFilesAlert buttons message = Alert
+	{ alertHeader = Just $ fromString $ unwords
+		[ "Old and deleted files are piling up --"
+		, message
+		]
+	, alertIcon = Just InfoIcon
+	, alertPriority = High
+	, alertButtons = buttons
+	, alertClosable = True
+	, alertClass = Message
+	, alertMessageRender = renderData
+	, alertCounter = 0
+	, alertBlockDisplay = True
+	, alertName = Just UnusedFilesAlert
+	, alertCombiner = Just $ fullCombiner $ \new _old -> new
+	, alertData = []
+	}
+
+brokenRepositoryAlert :: [AlertButton] -> Alert
+brokenRepositoryAlert = errorAlert "Serious problems have been detected with your repository. This needs your immediate attention!"
+
+repairingAlert :: String -> Alert
+repairingAlert repodesc = activityAlert Nothing
+	[ Tensed "Attempting to repair" "Repaired"
+	, UnTensed $ T.pack repodesc
+	]
+
+pairingAlert :: AlertButton -> Alert
+pairingAlert button = baseActivityAlert
+	{ alertData = [ UnTensed "Pairing in progress" ]
+	, alertPriority = High
+	, alertButtons = [button]
+	}
+
+pairRequestReceivedAlert :: String -> AlertButton -> Alert
+pairRequestReceivedAlert who button = Alert
+	{ alertClass = Message
+	, alertHeader = Nothing
+	, alertMessageRender = renderData
+	, alertData = [UnTensed $ T.pack $ who ++ " is sending a pair request."]
+	, alertCounter = 0
+	, alertBlockDisplay = False
+	, alertPriority = High
+	, alertClosable = True
+	, alertIcon = Just InfoIcon
+	, alertName = Just $ PairAlert who
+	, alertCombiner = Just $ dataCombiner $ \_old new -> new
+	, alertButtons = [button]
+	}
+
+pairRequestAcknowledgedAlert :: String -> Maybe AlertButton -> Alert
+pairRequestAcknowledgedAlert who button = baseActivityAlert
+	{ alertData = ["Pairing with", UnTensed (T.pack who), Tensed "in progress" "complete"]
+	, alertPriority = High
+	, alertName = Just $ PairAlert who
+	, alertCombiner = Just $ dataCombiner $ \_old new -> new
+	, alertButtons = maybeToList button
+	}
+
+connectionNeededAlert :: AlertButton -> Alert
+connectionNeededAlert button = Alert
+	{ alertHeader = Just "Share with friends, and keep your devices in sync across the cloud."
+	, alertIcon = Just ConnectionIcon
+	, alertPriority = High
+	, alertButtons = [button]
+	, alertClosable = True
+	, alertClass = Message
+	, alertMessageRender = renderData
+	, alertCounter = 0
+	, alertBlockDisplay = True
+	, alertName = Just ConnectionNeededAlert
+	, alertCombiner = Just $ dataCombiner $ \_old new -> new
+	, alertData = []
+	}
+
+cloudRepoNeededAlert :: Maybe String -> AlertButton -> Alert
+cloudRepoNeededAlert friendname button = Alert
+	{ alertHeader = Just $ fromString $ unwords
+		[ "Unable to download files from"
+		, (fromMaybe "your other devices" friendname) ++ "."
+		]
+	, alertIcon = Just ErrorIcon
+	, alertPriority = High
+	, alertButtons = [button]
+	, alertClosable = True
+	, alertClass = Message
+	, alertMessageRender = renderData
+	, alertCounter = 0
+	, alertBlockDisplay = True
+	, alertName = Just $ CloudRepoNeededAlert
+	, alertCombiner = Just $ dataCombiner $ \_old new -> new
+	, alertData = []
+	}
+
+remoteRemovalAlert :: String -> AlertButton -> Alert
+remoteRemovalAlert desc button = Alert
+	{ alertHeader = Just $ fromString $
+		"The repository \"" ++ desc ++ 
+		"\" has been emptied, and can now be removed."
+	, alertIcon = Just InfoIcon
+	, alertPriority = High
+	, alertButtons = [button]
+	, alertClosable = True
+	, alertClass = Message
+	, alertMessageRender = renderData
+	, alertCounter = 0
+	, alertBlockDisplay = True
+	, alertName = Just $ RemoteRemovalAlert desc
+	, alertCombiner = Just $ dataCombiner $ \_old new -> new
+	, alertData = []
+	}
+
+{- Show a message that relates to a list of files.
+ -
+ - The most recent several files are shown, and a count of any others. -}
+fileAlert :: TenseChunk -> [FilePath] -> Alert
+fileAlert msg files = (activityAlert Nothing shortfiles)
+	{ alertName = Just $ FileAlert msg
+	, alertMessageRender = renderer
+	, alertCounter = counter
+	, alertCombiner = Just $ fullCombiner combiner
+	}
+  where
+	maxfilesshown = 10
+
+	(!somefiles, !counter) = splitcounter (dedupadjacent files)
+	!shortfiles = map (fromString . shortFile . takeFileName) somefiles
+
+	renderer alert = tenseWords $ msg : alertData alert ++ showcounter
+	  where
+		showcounter = case alertCounter alert of
+			0 -> []
+			_ -> [fromString $ "and " ++ show (alertCounter alert) ++ " other files"]
+
+	dedupadjacent (x:y:rest)
+		| x == y = dedupadjacent (y:rest)
+		| otherwise = x : dedupadjacent (y:rest)
+	dedupadjacent (x:[]) = [x]
+	dedupadjacent [] = []
+
+	{- Note that this ensures the counter is never 1; no need to say 
+	 - "1 file" when the filename could be shown. -}
+	splitcounter l
+		| length l <= maxfilesshown = (l, 0)
+		| otherwise =
+			let (keep, rest) = splitAt (maxfilesshown - 1) l
+			in (keep, length rest)
+	
+	combiner new old =
+		let (!fs, n) = splitcounter $
+			dedupadjacent $ alertData new ++ alertData old
+		    !cnt = n + alertCounter new + alertCounter old
+		in old
+			{ alertData = fs
+			, alertCounter = cnt
+			}
+
+addFileAlert :: [FilePath] -> Alert
+addFileAlert = fileAlert (Tensed "Adding" "Added")
+
+{- This is only used as a success alert after a transfer, not during it. -}
+transferFileAlert :: Direction -> Bool -> FilePath -> Alert
+transferFileAlert direction True file
+	| direction == Upload = fileAlert "Uploaded" [file]
+	| otherwise = fileAlert "Downloaded" [file]
+transferFileAlert direction False file
+	| direction == Upload = fileAlert "Upload failed" [file]
+	| otherwise = fileAlert "Download failed" [file]
+
+dataCombiner :: ([TenseChunk] -> [TenseChunk] -> [TenseChunk]) -> AlertCombiner
+dataCombiner combiner = fullCombiner $
+	\new old -> old { alertData = alertData new `combiner` alertData old }
+
+fullCombiner :: (Alert -> Alert -> Alert) -> AlertCombiner
+fullCombiner combiner new old
+	| alertClass new /= alertClass old = Nothing
+	| alertName new == alertName old = 
+		Just $! new `combiner` old
+	| otherwise = Nothing
+
+shortFile :: FilePath -> String
+shortFile f
+	| len < maxlen = f
+	| otherwise = take half f ++ ".." ++ drop (len - half) f
+  where
+	len = length f
+	maxlen = 20
+	half = (maxlen - 2) `div` 2 
+

Assistant/Alert/Utility.hs

@@ -0,0 +1,130 @@
+{- git-annex assistant alert utilities
+ -
+ - Copyright 2012, 2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.Alert.Utility where
+
+import Common.Annex
+import Assistant.Types.Alert
+import Utility.Tense
+
+import qualified Data.Text as T
+import Data.Text (Text)
+import qualified Data.Map as M
+
+{- This is as many alerts as it makes sense to display at a time.
+ - A display might be smaller, or larger, the point is to not overwhelm the
+ - user with a ton of alerts. -}
+displayAlerts :: Int
+displayAlerts = 6
+
+{- This is not a hard maximum, but there's no point in keeping a great
+ - many filler alerts in an AlertMap, so when there's more than this many,
+ - they start being pruned, down toward displayAlerts. -}
+maxAlerts :: Int
+maxAlerts = displayAlerts * 2
+
+type AlertPair = (AlertId, Alert)
+
+{- The desired order is the reverse of:
+ -
+ - - Pinned alerts
+ - - High priority alerts, newest first
+ - - Medium priority Activity, newest first (mostly used for Activity)
+ - - Low priority alerts, newest first
+ - - Filler priorty alerts, newest first
+ - - Ties are broken by the AlertClass, with Errors etc coming first.
+ -}
+compareAlertPairs :: AlertPair -> AlertPair -> Ordering
+compareAlertPairs
+	(aid, Alert { alertClass = aclass, alertPriority = aprio })
+	(bid, Alert { alertClass = bclass, alertPriority = bprio })
+	 = compare aprio bprio
+		`mappend` compare aid bid
+			`mappend` compare aclass bclass
+
+sortAlertPairs :: [AlertPair] -> [AlertPair]
+sortAlertPairs = sortBy compareAlertPairs
+
+{- Renders an alert's header for display, if it has one. -}
+renderAlertHeader :: Alert -> Maybe Text
+renderAlertHeader alert = renderTense (alertTense alert) <$> alertHeader alert
+
+{- Renders an alert's message for display. -}
+renderAlertMessage :: Alert -> Text
+renderAlertMessage alert = renderTense (alertTense alert) $
+	(alertMessageRender alert) alert
+
+showAlert :: Alert -> String
+showAlert alert = T.unpack $ T.unwords $ catMaybes
+	[ renderAlertHeader alert
+	, Just $ renderAlertMessage alert
+	]
+
+alertTense :: Alert -> Tense
+alertTense alert
+	| alertClass alert == Activity = Present
+	| otherwise = Past
+
+{- Checks if two alerts display the same. -}
+effectivelySameAlert :: Alert -> Alert -> Bool
+effectivelySameAlert x y = all id 
+	[ alertClass x == alertClass y
+	, alertHeader x == alertHeader y
+	, alertData x == alertData y
+	, alertBlockDisplay x == alertBlockDisplay y
+	, alertClosable x == alertClosable y
+	, alertPriority x == alertPriority y
+	]
+
+makeAlertFiller :: Bool -> Alert -> Alert
+makeAlertFiller success alert
+	| isFiller alert = alert
+	| otherwise = alert
+		{ alertClass = if c == Activity then c' else c
+		, alertPriority = Filler
+		, alertClosable = True
+		, alertButtons = []
+		, alertIcon = Just $ if success then SuccessIcon else ErrorIcon
+		}
+  where
+	c = alertClass alert
+	c'
+		| success = Success
+		| otherwise = Error
+
+isFiller :: Alert -> Bool
+isFiller alert = alertPriority alert == Filler
+
+{- Updates the Alertmap, adding or updating an alert.
+ -
+ - Any old filler that looks the same as the alert is removed.
+ -
+ - Or, if the alert has an alertCombiner that combines it with
+ - an old alert, the old alert is replaced with the result, and the
+ - alert is removed.
+ -
+ - Old filler alerts are pruned once maxAlerts is reached.
+ -}
+mergeAlert :: AlertId -> Alert -> AlertMap -> AlertMap
+mergeAlert i al m = maybe updatePrune updateCombine (alertCombiner al)
+  where
+	pruneSame k al' = k == i || not (effectivelySameAlert al al')
+	pruneBloat m'
+		| bloat > 0 = M.fromList $ pruneold $ M.toList m'
+		| otherwise = m'
+	  where
+		bloat = M.size m' - maxAlerts
+		pruneold l =
+			let (f, rest) = partition (\(_, a) -> isFiller a) l
+			in drop bloat f ++ rest
+	updatePrune = pruneBloat $ M.filterWithKey pruneSame $
+		M.insertWith' const i al m
+	updateCombine combiner = 
+		let combined = M.mapMaybe (combiner al) m
+		in if M.null combined
+			then updatePrune
+			else M.delete i $ M.union combined m

Assistant/BranchChange.hs

@@ -0,0 +1,19 @@
+{- git-annex assistant git-annex branch change tracking
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.BranchChange where
+
+import Assistant.Common
+import Assistant.Types.BranchChange
+
+import Control.Concurrent.MSampleVar
+
+branchChanged :: Assistant ()
+branchChanged = flip writeSV () <<~ (fromBranchChangeHandle . branchChangeHandle)
+
+waitBranchChange :: Assistant ()
+waitBranchChange = readSV <<~ (fromBranchChangeHandle . branchChangeHandle)

Assistant/Changes.hs

@@ -0,0 +1,47 @@
+{- git-annex assistant change tracking
+ -
+ - Copyright 2012-2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.Changes where
+
+import Assistant.Common
+import Assistant.Types.Changes
+import Utility.TList
+
+import Data.Time.Clock
+import Control.Concurrent.STM
+
+{- Handlers call this when they made a change that needs to get committed. -}
+madeChange :: FilePath -> ChangeInfo -> Assistant (Maybe Change)
+madeChange f t = Just <$> (Change <$> liftIO getCurrentTime <*> pure f <*> pure t)
+
+noChange :: Assistant (Maybe Change)
+noChange = return Nothing
+
+{- Indicates an add needs to be done, but has not started yet. -}
+pendingAddChange :: FilePath -> Assistant (Maybe Change)
+pendingAddChange f = Just <$> (PendingAddChange <$> liftIO getCurrentTime <*> pure f)
+
+{- Gets all unhandled changes.
+ - Blocks until at least one change is made. -}
+getChanges :: Assistant [Change]
+getChanges = (atomically . getTList) <<~ changePool
+
+{- Gets all unhandled changes, without blocking. -}
+getAnyChanges :: Assistant [Change]
+getAnyChanges = (atomically . takeTList) <<~ changePool
+
+{- Puts unhandled changes back into the pool.
+ - Note: Original order is not preserved. -}
+refillChanges :: [Change] -> Assistant ()
+refillChanges cs = (atomically . flip appendTList cs) <<~ changePool
+
+{- Records a change to the pool. -}
+recordChange :: Change -> Assistant ()
+recordChange c = (atomically . flip snocTList c) <<~ changePool
+
+recordChanges :: [Change] -> Assistant ()
+recordChanges = refillChanges

Assistant/Commits.hs

@@ -0,0 +1,23 @@
+{- git-annex assistant commit tracking
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.Commits where
+
+import Assistant.Common
+import Assistant.Types.Commits
+import Utility.TList
+
+import Control.Concurrent.STM
+
+{- Gets all unhandled commits.
+ - Blocks until at least one commit is made. -}
+getCommits :: Assistant [Commit]
+getCommits = (atomically . getTList) <<~ commitChan
+
+{- Records a commit in the channel. -}
+recordCommit :: Assistant ()
+recordCommit = (atomically . flip consTList Commit) <<~ commitChan

Assistant/Common.hs

@@ -0,0 +1,14 @@
+{- Common infrastructure for the git-annex assistant.
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.Common (module X) where
+
+import Common.Annex as X
+import Assistant.Monad as X
+import Assistant.Types.DaemonStatus as X
+import Assistant.Types.NamedThread as X
+import Assistant.Types.Alert as X

Assistant/CredPairCache.hs

@@ -0,0 +1,53 @@
+{- git-annex assistant CredPair cache.
+ -
+ - Copyright 2014 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE BangPatterns #-}
+
+module Assistant.CredPairCache (
+	cacheCred,
+	getCachedCred,
+	expireCachedCred,
+) where
+
+import Assistant.Types.CredPairCache
+import Types.Creds
+import Assistant.Common
+import Utility.ThreadScheduler
+
+import qualified Data.Map as M
+import Control.Concurrent
+
+{- Caches a CredPair, but only for a limited time, after which it
+ - will expire.
+ -
+ - Note that repeatedly caching the same CredPair
+ - does not reset its expiry time.
+ -}
+cacheCred :: CredPair -> Seconds -> Assistant ()
+cacheCred (login, password) expireafter = do
+	cache <- getAssistant credPairCache
+	liftIO $ do
+		changeStrict cache $ M.insert login password
+		void $ forkIO $ do
+			threadDelaySeconds expireafter
+			changeStrict cache $ M.delete login
+
+getCachedCred :: Login -> Assistant (Maybe Password)
+getCachedCred login = do
+	cache <- getAssistant credPairCache
+	liftIO $ M.lookup login <$> readMVar cache
+
+expireCachedCred :: Login -> Assistant ()
+expireCachedCred login = do
+	cache <- getAssistant credPairCache
+	liftIO $ changeStrict cache $ M.delete login
+
+{- Update map strictly to avoid keeping references to old creds in memory. -}
+changeStrict :: CredPairCache -> (M.Map Login Password -> M.Map Login Password) -> IO ()
+changeStrict cache a = modifyMVar_ cache $ \m -> do
+	let !m' = a m
+	return m'

Assistant/DaemonStatus.hs

@@ -0,0 +1,271 @@
+{- git-annex assistant daemon status
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE BangPatterns #-}
+
+module Assistant.DaemonStatus where
+
+import Assistant.Common
+import Assistant.Alert.Utility
+import Utility.Tmp
+import Assistant.Types.NetMessager
+import Utility.NotificationBroadcaster
+import Logs.Transfer
+import Logs.Trust
+import qualified Remote
+import qualified Types.Remote as Remote
+import qualified Git
+
+import Control.Concurrent.STM
+import System.Posix.Types
+import Data.Time.Clock.POSIX
+import Data.Time
+import System.Locale
+import qualified Data.Map as M
+import qualified Data.Set as S
+import qualified Data.Text as T
+
+getDaemonStatus :: Assistant DaemonStatus
+getDaemonStatus = (atomically . readTMVar) <<~ daemonStatusHandle
+
+modifyDaemonStatus_ :: (DaemonStatus -> DaemonStatus) -> Assistant ()
+modifyDaemonStatus_ a = modifyDaemonStatus $ \s -> (a s, ())
+
+modifyDaemonStatus :: (DaemonStatus -> (DaemonStatus, b)) -> Assistant b
+modifyDaemonStatus a = do
+	dstatus <- getAssistant daemonStatusHandle
+	liftIO $ do
+		(s, b) <- atomically $ do
+			r@(!s, _) <- a <$> takeTMVar dstatus
+			putTMVar dstatus s
+			return r
+		sendNotification $ changeNotifier s
+		return b
+
+{- Returns a function that updates the lists of syncable remotes
+ - and other associated information. -}
+calcSyncRemotes :: Annex (DaemonStatus -> DaemonStatus)
+calcSyncRemotes = do
+	rs <- filter (remoteAnnexSync . Remote.gitconfig) .
+		concat . Remote.byCost <$> Remote.remoteList
+	alive <- trustExclude DeadTrusted (map Remote.uuid rs)
+	let good r = Remote.uuid r `elem` alive
+	let syncable = filter good rs
+	let syncdata = filter (not . remoteAnnexIgnore . Remote.gitconfig) $
+		filter (not . Remote.isXMPPRemote) syncable
+
+	return $ \dstatus -> dstatus
+		{ syncRemotes = syncable
+		, syncGitRemotes = filter Remote.gitSyncableRemote syncable
+		, syncDataRemotes = syncdata
+		, syncingToCloudRemote = any iscloud syncdata
+		}
+  where
+	iscloud r = not (Remote.readonly r) && Remote.availability r == Remote.GloballyAvailable
+
+{- Updates the syncRemotes list from the list of all remotes in Annex state. -}
+updateSyncRemotes :: Assistant ()
+updateSyncRemotes = do
+	modifyDaemonStatus_ =<< liftAnnex calcSyncRemotes
+	status <- getDaemonStatus
+	liftIO $ sendNotification $ syncRemotesNotifier status
+
+	when (syncingToCloudRemote status) $
+		updateAlertMap $
+			M.filter $ \alert ->
+				alertName alert /= Just CloudRepoNeededAlert
+
+changeCurrentlyConnected :: (S.Set UUID -> S.Set UUID) -> Assistant ()
+changeCurrentlyConnected sm = do
+	modifyDaemonStatus_ $ \ds -> ds
+		{ currentlyConnectedRemotes = sm (currentlyConnectedRemotes ds)
+		}
+	v <- currentlyConnectedRemotes <$> getDaemonStatus
+	debug [show v]
+	liftIO . sendNotification =<< syncRemotesNotifier <$> getDaemonStatus
+
+updateScheduleLog :: Assistant ()
+updateScheduleLog =
+	liftIO . sendNotification =<< scheduleLogNotifier <$> getDaemonStatus
+
+{- Load any previous daemon status file, and store it in a MVar for this
+ - process to use as its DaemonStatus. Also gets current transfer status. -}
+startDaemonStatus :: Annex DaemonStatusHandle
+startDaemonStatus = do
+	file <- fromRepo gitAnnexDaemonStatusFile
+	status <- liftIO $
+		flip catchDefaultIO (readDaemonStatusFile file) =<< newDaemonStatus
+	transfers <- M.fromList <$> getTransfers
+	addsync <- calcSyncRemotes
+	liftIO $ atomically $ newTMVar $ addsync $ status
+		{ scanComplete = False
+		, sanityCheckRunning = False
+		, currentTransfers = transfers
+		}
+
+{- Don't just dump out the structure, because it will change over time,
+ - and parts of it are not relevant. -}
+writeDaemonStatusFile :: FilePath -> DaemonStatus -> IO ()
+writeDaemonStatusFile file status = 
+	viaTmp writeFile file =<< serialized <$> getPOSIXTime
+  where
+	serialized now = unlines
+		[ "lastRunning:" ++ show now
+		, "scanComplete:" ++ show (scanComplete status)
+		, "sanityCheckRunning:" ++ show (sanityCheckRunning status)
+		, "lastSanityCheck:" ++ maybe "" show (lastSanityCheck status)
+		]
+
+readDaemonStatusFile :: FilePath -> IO DaemonStatus
+readDaemonStatusFile file = parse <$> newDaemonStatus <*> readFile file
+  where
+	parse status = foldr parseline status . lines
+	parseline line status
+		| key == "lastRunning" = parseval readtime $ \v ->
+			status { lastRunning = Just v }
+		| key == "scanComplete" = parseval readish $ \v ->
+			status { scanComplete = v }
+		| key == "sanityCheckRunning" = parseval readish $ \v ->
+			status { sanityCheckRunning = v }
+		| key == "lastSanityCheck" = parseval readtime $ \v ->
+			status { lastSanityCheck = Just v }
+		| otherwise = status -- unparsable line
+	  where
+		(key, value) = separate (== ':') line
+		parseval parser a = maybe status a (parser value)
+		readtime s = do
+			d <- parseTime defaultTimeLocale "%s%Qs" s
+			Just $ utcTimeToPOSIXSeconds d
+
+{- Checks if a time stamp was made after the daemon was lastRunning.
+ -
+ - Some slop is built in; this really checks if the time stamp was made
+ - at least ten minutes after the daemon was lastRunning. This is to
+ - ensure the daemon shut down cleanly, and deal with minor clock skew.
+ -
+ - If the daemon has never ran before, this always returns False.
+ -}
+afterLastDaemonRun :: EpochTime -> DaemonStatus -> Bool
+afterLastDaemonRun timestamp status = maybe False (< t) (lastRunning status)
+  where
+	t = realToFrac (timestamp + slop) :: POSIXTime
+	slop = fromIntegral tenMinutes
+
+tenMinutes :: Int
+tenMinutes = 10 * 60
+
+{- Mutates the transfer map. Runs in STM so that the transfer map can
+ - be modified in the same transaction that modifies the transfer queue.
+ - Note that this does not send a notification of the change; that's left
+ - to the caller. -}
+adjustTransfersSTM :: DaemonStatusHandle -> (TransferMap -> TransferMap) -> STM ()
+adjustTransfersSTM dstatus a = do
+	s <- takeTMVar dstatus
+	let !v = a (currentTransfers s)
+	putTMVar dstatus $ s { currentTransfers = v }
+
+{- Checks if a transfer is currently running. -}
+checkRunningTransferSTM :: DaemonStatusHandle -> Transfer -> STM Bool
+checkRunningTransferSTM dstatus t = M.member t . currentTransfers
+	<$> readTMVar dstatus
+
+{- Alters a transfer's info, if the transfer is in the map. -}
+alterTransferInfo :: Transfer -> (TransferInfo -> TransferInfo) -> Assistant ()
+alterTransferInfo t a = updateTransferInfo' $ M.adjust a t
+
+{- Updates a transfer's info. Adds the transfer to the map if necessary,
+ - or if already present, updates it while preserving the old transferTid,
+ - transferPaused, and bytesComplete values, which are not written to disk. -}
+updateTransferInfo :: Transfer -> TransferInfo -> Assistant ()
+updateTransferInfo t info = updateTransferInfo' $ M.insertWith' merge t info
+  where
+	merge new old = new
+		{ transferTid = maybe (transferTid new) Just (transferTid old)
+		, transferPaused = transferPaused new || transferPaused old
+		, bytesComplete = maybe (bytesComplete new) Just (bytesComplete old)
+		}
+
+updateTransferInfo' :: (TransferMap -> TransferMap) -> Assistant ()
+updateTransferInfo' a = notifyTransfer `after` modifyDaemonStatus_ update
+  where
+	update s = s { currentTransfers = a (currentTransfers s) }
+
+{- Removes a transfer from the map, and returns its info. -}
+removeTransfer :: Transfer -> Assistant (Maybe TransferInfo)
+removeTransfer t = notifyTransfer `after` modifyDaemonStatus remove
+  where
+	remove s =
+		let (info, ts) = M.updateLookupWithKey
+			(\_k _v -> Nothing)
+			t (currentTransfers s)
+		in (s { currentTransfers = ts }, info)
+
+{- Send a notification when a transfer is changed. -}
+notifyTransfer :: Assistant ()
+notifyTransfer = do
+	dstatus <- getAssistant daemonStatusHandle
+	liftIO $ sendNotification
+		=<< transferNotifier <$> atomically (readTMVar dstatus)
+
+{- Send a notification when alerts are changed. -}
+notifyAlert :: Assistant ()
+notifyAlert = do
+	dstatus <- getAssistant daemonStatusHandle
+	liftIO $ sendNotification
+		=<< alertNotifier <$> atomically (readTMVar dstatus)
+
+{- Returns the alert's identifier, which can be used to remove it. -}
+addAlert :: Alert -> Assistant AlertId
+addAlert alert = do
+	notice [showAlert alert]
+	notifyAlert `after` modifyDaemonStatus add
+  where
+	add s = (s { lastAlertId = i, alertMap = m }, i)
+	  where
+		!i = nextAlertId $ lastAlertId s
+		!m = mergeAlert i alert (alertMap s)
+
+removeAlert :: AlertId -> Assistant ()
+removeAlert i = updateAlert i (const Nothing)
+
+updateAlert :: AlertId -> (Alert -> Maybe Alert) -> Assistant ()
+updateAlert i a = updateAlertMap $ \m -> M.update a i m
+
+updateAlertMap :: (AlertMap -> AlertMap) -> Assistant ()
+updateAlertMap a = notifyAlert `after` modifyDaemonStatus_ update
+  where
+	update s = 
+		let !m = a (alertMap s)
+		in s { alertMap = m }
+
+{- Displays an alert while performing an activity that returns True on
+ - success.
+ -
+ - The alert is left visible afterwards, as filler.
+ - Old filler is pruned, to prevent the map growing too large. -}
+alertWhile :: Alert -> Assistant Bool -> Assistant Bool
+alertWhile alert a = alertWhile' alert $ do
+	r <- a
+	return (r, r)
+
+{- Like alertWhile, but allows the activity to return a value too. -}
+alertWhile' :: Alert -> Assistant (Bool, a) -> Assistant a
+alertWhile' alert a = do
+	let alert' = alert { alertClass = Activity }
+	i <- addAlert alert'
+	(ok, r) <- a
+	updateAlertMap $ mergeAlert i $ makeAlertFiller ok alert'
+	return r
+
+{- Displays an alert while performing an activity, then removes it. -}
+alertDuring :: Alert -> Assistant a -> Assistant a
+alertDuring alert a = do
+	i <- addAlert $ alert { alertClass = Activity }
+	removeAlert  i `after` a
+
+getXMPPClientID :: Remote -> ClientID
+getXMPPClientID r = T.pack $ drop (length "xmpp::") (Git.repoLocation (Remote.repo r))

Assistant/DeleteRemote.hs

@@ -0,0 +1,89 @@
+{- git-annex assistant remote deletion utilities
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Assistant.DeleteRemote where
+
+import Assistant.Common
+import Assistant.Types.UrlRenderer
+import Assistant.TransferQueue
+import Logs.Transfer
+import Logs.Location
+import Assistant.DaemonStatus
+import qualified Remote
+import Remote.List
+import qualified Git.Remote.Remove
+import Logs.Trust
+import qualified Annex
+
+#ifdef WITH_WEBAPP
+import Assistant.WebApp.Types
+import Assistant.Alert
+import qualified Data.Text as T
+#endif
+
+{- Removes a remote (but leave the repository as-is), and returns the old
+ - Remote data. -}
+disableRemote :: UUID -> Assistant Remote
+disableRemote uuid = do
+	remote <- fromMaybe (error "unknown remote")
+		<$> liftAnnex (Remote.remoteFromUUID uuid)
+	liftAnnex $ do
+		inRepo $ Git.Remote.Remove.remove (Remote.name remote)
+		void $ remoteListRefresh
+	updateSyncRemotes
+	return remote
+
+{- Removes a remote, marking it dead .-}
+removeRemote :: UUID -> Assistant Remote
+removeRemote uuid = do
+	liftAnnex $ trustSet uuid DeadTrusted
+	disableRemote uuid
+
+{- Called when a Remote is probably empty, to remove it.
+ -
+ - This does one last check for any objects remaining in the Remote,
+ - and if there are any, queues Downloads of them, and defers removing
+ - the remote for later. This is to catch any objects not referred to
+ - in keys in the current branch.
+ -}
+removableRemote :: UrlRenderer -> UUID -> Assistant ()
+removableRemote urlrenderer uuid = do
+	keys <- getkeys
+	if null keys
+		then finishRemovingRemote urlrenderer uuid
+		else do
+			r <- fromMaybe (error "unknown remote")
+				<$> liftAnnex (Remote.remoteFromUUID uuid)
+			mapM_ (queueremaining r) keys
+  where
+	queueremaining r k = 
+		queueTransferWhenSmall "remaining object in unwanted remote"
+			Nothing (Transfer Download uuid k) r
+	{- Scanning for keys can take a long time; do not tie up
+	 - the Annex monad while doing it, so other threads continue to
+	 - run. -}
+	getkeys = do
+		a <- liftAnnex $ Annex.withCurrentState $ loggedKeysFor uuid
+		liftIO a
+
+{- With the webapp, this asks the user to click on a button to finish
+ - removing the remote.
+ -
+ - Without the webapp, just do the removal now.
+ -}
+finishRemovingRemote :: UrlRenderer -> UUID -> Assistant ()
+#ifdef WITH_WEBAPP
+finishRemovingRemote urlrenderer uuid = do
+	desc <- liftAnnex $ Remote.prettyUUID uuid
+	button <- mkAlertButton True (T.pack "Finish deletion process") urlrenderer $
+		FinishDeleteRepositoryR uuid
+	void $ addAlert $ remoteRemovalAlert desc button
+#else
+finishRemovingRemote _ uuid = void $ removeRemote uuid
+#endif

Assistant/Drop.hs

@@ -0,0 +1,25 @@
+{- git-annex assistant dropping of unwanted content
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.Drop (
+	handleDrops,
+	handleDropsFrom,
+) where
+
+import Assistant.Common
+import Assistant.DaemonStatus
+import Annex.Drop (handleDropsFrom, Reason)
+import Logs.Location
+import CmdLine.Action
+
+{- Drop from local and/or remote when allowed by the preferred content and
+ - numcopies settings. -}
+handleDrops :: Reason -> Bool -> Key -> AssociatedFile -> Maybe Remote -> Assistant ()
+handleDrops reason fromhere key f knownpresentremote = do
+	syncrs <- syncDataRemotes <$> getDaemonStatus
+	locs <- liftAnnex $ loggedLocations key
+	liftAnnex $ handleDropsFrom locs syncrs reason fromhere key f knownpresentremote callCommandAction

Assistant/Fsck.hs

@@ -0,0 +1,50 @@
+{- git-annex assistant fscking
+ -
+ - Copyright 2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU AGPL version 3 or higher.
+ -}
+
+module Assistant.Fsck where
+
+import Assistant.Common
+import Types.ScheduledActivity
+import qualified Types.Remote as Remote
+import Annex.UUID
+import Assistant.Alert
+import Assistant.Types.UrlRenderer
+import Logs.Schedule
+import qualified Annex
+
+import qualified Data.Set as S
+
+{- Displays a nudge in the webapp if a fsck is not configured for
+ - the specified remote, or for the local repository. -}
+fsckNudge :: UrlRenderer -> Maybe Remote -> Assistant ()
+fsckNudge urlrenderer mr
+	| maybe True fsckableRemote mr =
+		whenM (liftAnnex $ annexFsckNudge <$> Annex.getGitConfig) $
+			unlessM (liftAnnex $ checkFscked mr) $
+				notFsckedNudge urlrenderer mr
+	| otherwise = noop
+
+fsckableRemote :: Remote -> Bool
+fsckableRemote = isJust . Remote.remoteFsck
+
+{- Checks if the remote, or the local repository, has a fsck scheduled.
+ - Only looks at fscks configured to run via the local repository, not
+ - other repositories. -}
+checkFscked :: Maybe Remote -> Annex Bool
+checkFscked mr = any wanted . S.toList <$> (scheduleGet =<< getUUID)
+  where
+	wanted = case mr of
+		Nothing -> isSelfFsck
+		Just r -> flip isFsckOf (Remote.uuid r)
+
+isSelfFsck :: ScheduledActivity -> Bool
+isSelfFsck (ScheduledSelfFsck _ _) = True
+isSelfFsck _ = False
+
+isFsckOf :: ScheduledActivity -> UUID -> Bool
+isFsckOf (ScheduledRemoteFsck u _ _) u' = u == u'
+isFsckOf _ _ = False

Assistant/Gpg.hs

@@ -0,0 +1,36 @@
+{- git-annex assistant gpg stuff
+ -
+ - Copyright 2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU AGPL version 3 or higher.
+ -}
+
+{-# LANGUAGE QuasiQuotes, TemplateHaskell, OverloadedStrings #-}
+
+module Assistant.Gpg where
+
+import Utility.Gpg
+import Utility.UserInfo
+import Types.Remote (RemoteConfigKey)
+
+import qualified Data.Map as M
+
+{- Generates a gpg user id that is not used by any existing secret key -}
+newUserId :: IO UserId
+newUserId = do
+	oldkeys <- secretKeys
+	username <- myUserName
+	let basekeyname = username ++ "'s git-annex encryption key"
+	return $ Prelude.head $ filter (\n -> M.null $ M.filter (== n) oldkeys)
+		( basekeyname
+		: map (\n -> basekeyname ++ show n) ([2..] :: [Int])
+		)
+
+data EnableEncryption = HybridEncryption | SharedEncryption | NoEncryption
+	deriving (Eq)
+
+{- Generates Remote configuration for encryption. -}
+configureEncryption :: EnableEncryption -> (RemoteConfigKey, String)
+configureEncryption SharedEncryption = ("encryption", "shared")
+configureEncryption NoEncryption = ("encryption", "none")
+configureEncryption HybridEncryption = ("encryption", "hybrid")

Assistant/Install.hs

@@ -0,0 +1,179 @@
+{- Assistant installation
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Assistant.Install where
+
+import Assistant.Common
+import Assistant.Install.AutoStart
+import Config.Files
+import Utility.FileMode
+import Utility.Shell
+import Utility.Tmp
+import Utility.Env
+import Utility.SshConfig
+
+#ifdef darwin_HOST_OS
+import Utility.OSX
+#else
+import Utility.FreeDesktop
+#ifdef linux_HOST_OS
+import Utility.UserInfo
+#endif
+import Assistant.Install.Menu
+#endif
+
+standaloneAppBase :: IO (Maybe FilePath)
+standaloneAppBase = getEnv "GIT_ANNEX_APP_BASE"
+
+{- The standalone app does not have an installation process.
+ - So when it's run, it needs to set up autostarting of the assistant
+ - daemon, as well as writing the programFile, and putting the
+ - git-annex-shell and git-annex-wrapper wrapper scripts into ~/.ssh
+ -
+ - Note that this is done every time it's started, so if the user moves
+ - it around, the paths this sets up won't break.
+ -
+ - File manager hook script installation is done even for
+ - packaged apps, since it has to go into the user's home directory.
+ -}
+ensureInstalled :: IO ()
+ensureInstalled = go =<< standaloneAppBase
+  where
+	go Nothing = installFileManagerHooks "git-annex"
+	go (Just base) = do
+		let program = base </> "git-annex"
+		programfile <- programFile
+		createDirectoryIfMissing True (parentDir programfile)
+		writeFile programfile program
+
+#ifdef darwin_HOST_OS
+		autostartfile <- userAutoStart osxAutoStartLabel
+#else
+		menufile <- desktopMenuFilePath "git-annex" <$> userDataDir
+		icondir <- iconDir <$> userDataDir
+		installMenu program menufile base icondir
+		autostartfile <- autoStartPath "git-annex" <$> userConfigDir
+#endif
+		installAutoStart program autostartfile
+
+		sshdir <- sshDir
+		let runshell var = "exec " ++ base </> "runshell " ++ var
+		let rungitannexshell var = runshell $ "git-annex-shell -c \"" ++ var ++ "\""
+
+		installWrapper (sshdir </> "git-annex-shell") $ unlines
+			[ shebang_local
+			, "set -e"
+			, "if [ \"x$SSH_ORIGINAL_COMMAND\" != \"x\" ]; then"
+			,   rungitannexshell "$SSH_ORIGINAL_COMMAND"
+			, "else"
+			,   rungitannexshell "$@"
+			, "fi"
+			]
+		installWrapper (sshdir </> "git-annex-wrapper") $ unlines
+			[ shebang_local
+			, "set -e"
+			, runshell "\"$@\""
+			]
+
+		installFileManagerHooks program
+
+installWrapper :: FilePath -> String -> IO ()
+installWrapper file content = do
+	curr <- catchDefaultIO "" $ readFileStrict file
+	when (curr /= content) $ do
+		createDirectoryIfMissing True (parentDir file)
+		viaTmp writeFile file content
+		modifyFileMode file $ addModes [ownerExecuteMode]
+
+installFileManagerHooks :: FilePath -> IO ()
+#ifdef linux_HOST_OS
+installFileManagerHooks program = do
+	let actions = ["get", "drop", "undo"]
+
+	-- Gnome
+	nautilusScriptdir <- (\d -> d </> "nautilus" </> "scripts") <$> userDataDir
+	createDirectoryIfMissing True nautilusScriptdir
+	forM_ actions $
+		genNautilusScript nautilusScriptdir
+
+	-- KDE
+	home <- myHomeDir
+	let kdeServiceMenusdir = home </> ".kde" </> "share" </> "kde4" </> "services" </> "ServiceMenus"
+	createDirectoryIfMissing True kdeServiceMenusdir
+	writeFile (kdeServiceMenusdir </> "git-annex.desktop")
+		(kdeDesktopFile actions)
+  where
+	genNautilusScript scriptdir action =
+		installscript (scriptdir </> scriptname action) $ unlines
+			[ shebang_local
+			, autoaddedcomment
+			, "exec " ++ program ++ " " ++ action ++ " --notify-start --notify-finish -- \"$@\""
+			]
+	scriptname action = "git-annex " ++ action
+	installscript f c = whenM (safetoinstallscript f) $ do
+		writeFile f c
+		modifyFileMode f $ addModes [ownerExecuteMode]
+	safetoinstallscript f = catchDefaultIO True $
+		elem autoaddedcomment . lines <$> readFileStrict f
+	autoaddedcomment = "# " ++ autoaddedmsg ++ " (To disable, chmod 600 this file.)"
+	autoaddedmsg = "Automatically added by git-annex, do not edit."
+
+	kdeDesktopFile actions = unlines $ concat $
+		kdeDesktopHeader actions : map kdeDesktopAction actions
+	kdeDesktopHeader actions =
+		[ "# " ++ autoaddedmsg
+		, "[Desktop Entry]"
+		, "Type=Service"
+		, "ServiceTypes=all/allfiles"
+		, "MimeType=all/all;"
+		, "Actions=" ++ intercalate ";" (map kdeDesktopSection actions)
+		, "X-KDE-Priority=TopLevel"
+		, "X-KDE-Submenu=Git-Annex"
+		, "X-KDE-Icon=git-annex"
+		, "X-KDE-ServiceTypes=KonqPopupMenu/Plugin"
+		]
+	kdeDesktopSection command = "GitAnnex" ++ command
+	kdeDesktopAction command = 
+		[ ""
+		, "[Desktop Action " ++ kdeDesktopSection command ++ "]"
+		, "Name=" ++ command
+		, "Icon=git-annex"
+		, unwords
+			[ "Exec=sh -c 'cd \"$(dirname '%U')\" &&"
+			, program
+			, command
+			, "--notify-start --notify-finish -- %U'"
+			]
+		]
+#else
+installFileManagerHooks _ = noop
+#endif
+
+{- Returns a cleaned up environment that lacks settings used to make the
+ - standalone builds use their bundled libraries and programs.
+ - Useful when calling programs not included in the standalone builds.
+ -
+ - For a non-standalone build, returns Nothing.
+ -}
+cleanEnvironment :: IO (Maybe [(String, String)])
+cleanEnvironment = clean <$> getEnvironment
+  where
+	clean environ
+		| null vars = Nothing
+		| otherwise = Just $ catMaybes $ map (restoreorig environ) environ
+		| otherwise = Nothing
+	  where
+		vars = words $ fromMaybe "" $
+			lookup "GIT_ANNEX_STANDLONE_ENV" environ
+		restoreorig oldenviron p@(k, _v)
+			| k `elem` vars = case lookup ("ORIG_" ++ k) oldenviron of
+				(Just v')
+					| not (null v') -> Just (k, v')
+				_ -> Nothing
+			| otherwise = Just p

Assistant/Install/AutoStart.hs

@@ -0,0 +1,39 @@
+{- Assistant autostart file installation
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Assistant.Install.AutoStart where
+
+import Utility.FreeDesktop
+#ifdef darwin_HOST_OS
+import Utility.OSX
+import Utility.Path
+import System.Directory
+#endif
+
+installAutoStart :: FilePath -> FilePath -> IO ()
+installAutoStart command file = do
+#ifdef darwin_HOST_OS
+	createDirectoryIfMissing True (parentDir file)
+	writeFile file $ genOSXAutoStartFile osxAutoStartLabel command
+		["assistant", "--autostart"]
+#else
+	writeDesktopMenuFile (fdoAutostart command) file
+#endif
+
+osxAutoStartLabel :: String
+osxAutoStartLabel = "com.branchable.git-annex.assistant"
+
+fdoAutostart :: FilePath -> DesktopEntry
+fdoAutostart command = genDesktopEntry
+	"Git Annex Assistant"
+	"Autostart"
+	False
+	(command ++ " assistant --autostart")
+	Nothing
+	[]

Assistant/Install/Menu.hs

@@ -0,0 +1,47 @@
+{- Assistant menu installation.
+ -
+ - Copyright 2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Assistant.Install.Menu where
+
+import Common
+
+import Utility.FreeDesktop
+
+installMenu :: FilePath -> FilePath -> FilePath -> FilePath -> IO ()
+#ifdef darwin_HOST_OS
+installMenu _command _menufile _iconsrcdir _icondir = return ()
+#else
+installMenu command menufile iconsrcdir icondir = do
+	writeDesktopMenuFile (fdoDesktopMenu command) menufile
+	installIcon (iconsrcdir </> "logo.svg") $
+		iconFilePath (iconBaseName ++ ".svg") "scalable" icondir
+	installIcon (iconsrcdir </> "logo_16x16.png") $
+		iconFilePath (iconBaseName ++ ".png") "16x16" icondir
+#endif
+
+{- The command can be either just "git-annex", or the full path to use
+ - to run it. -}
+fdoDesktopMenu :: FilePath -> DesktopEntry
+fdoDesktopMenu command = genDesktopEntry
+	"Git Annex"
+	"Track and sync the files in your Git Annex"
+	False
+	(command ++ " webapp")
+	(Just iconBaseName)
+	["Network", "FileTransfer"]
+
+installIcon :: FilePath -> FilePath -> IO ()
+installIcon src dest = do
+	createDirectoryIfMissing True (parentDir dest)
+	withBinaryFile src ReadMode $ \hin ->
+		withBinaryFile dest WriteMode $ \hout ->
+			hGetContents hin >>= hPutStr hout
+
+iconBaseName :: String
+iconBaseName = "git-annex"

Assistant/MakeRemote.hs

@@ -0,0 +1,171 @@
+{- git-annex assistant remote creation utilities
+ -
+ - Copyright 2012, 2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.MakeRemote where
+
+import Assistant.Common
+import Assistant.Ssh
+import qualified Types.Remote as R
+import qualified Remote
+import Remote.List
+import qualified Remote.Rsync as Rsync
+import qualified Remote.GCrypt as GCrypt
+import qualified Git
+import qualified Git.Command
+import qualified Command.InitRemote
+import Logs.UUID
+import Logs.Remote
+import Git.Remote
+import Git.Types (RemoteName)
+import Creds
+import Assistant.Gpg
+import Utility.Gpg (KeyId)
+
+import qualified Data.Map as M
+
+{- Sets up a new git or rsync remote, accessed over ssh. -}
+makeSshRemote :: SshData -> Annex RemoteName
+makeSshRemote sshdata = maker (sshRepoName sshdata) (genSshUrl sshdata)
+  where
+	maker
+		| onlyCapability sshdata RsyncCapable = makeRsyncRemote
+		| otherwise = makeGitRemote
+
+{- Runs an action that returns a name of the remote, and finishes adding it. -}
+addRemote :: Annex RemoteName -> Annex Remote
+addRemote a = do
+	name <- a
+	void remoteListRefresh
+	maybe (error "failed to add remote") return
+		=<< Remote.byName (Just name)
+
+{- Inits a rsync special remote, and returns its name. -}
+makeRsyncRemote :: RemoteName -> String -> Annex String
+makeRsyncRemote name location = makeRemote name location $ const $ void $
+	go =<< Command.InitRemote.findExisting name
+  where
+	go Nothing = setupSpecialRemote name Rsync.remote config Nothing
+		(Nothing, Command.InitRemote.newConfig name)
+	go (Just (u, c)) = setupSpecialRemote name Rsync.remote config Nothing
+		(Just u, c)
+	config = M.fromList
+		[ ("encryption", "shared")
+		, ("rsyncurl", location)
+		, ("type", "rsync")
+		]
+
+{- Inits a gcrypt special remote, and returns its name. -}
+makeGCryptRemote :: RemoteName -> String -> KeyId -> Annex RemoteName
+makeGCryptRemote remotename location keyid = 
+	initSpecialRemote remotename GCrypt.remote Nothing $ M.fromList
+		[ ("type", "gcrypt")
+		, ("gitrepo", location)
+		, configureEncryption HybridEncryption
+		, ("keyid", keyid)
+		]
+
+type SpecialRemoteMaker = RemoteName -> RemoteType -> Maybe CredPair -> R.RemoteConfig -> Annex RemoteName
+
+{- Inits a new special remote. The name is used as a suggestion, but
+ - will be changed if there is already a special remote with that name. -}
+initSpecialRemote :: SpecialRemoteMaker
+initSpecialRemote name remotetype mcreds config = go 0
+  where
+	go :: Int -> Annex RemoteName
+	go n = do
+		let fullname = if n == 0  then name else name ++ show n
+		r <- Command.InitRemote.findExisting fullname
+		case r of
+			Nothing -> setupSpecialRemote fullname remotetype config mcreds
+				(Nothing, Command.InitRemote.newConfig fullname)
+			Just _ -> go (n + 1)
+
+{- Enables an existing special remote. -}
+enableSpecialRemote :: SpecialRemoteMaker
+enableSpecialRemote name remotetype mcreds config = do
+	r <- Command.InitRemote.findExisting name
+	case r of
+		Nothing -> error $ "Cannot find a special remote named " ++ name
+		Just (u, c) -> setupSpecialRemote' False name remotetype config mcreds (Just u, c)
+
+setupSpecialRemote :: RemoteName -> RemoteType -> R.RemoteConfig -> Maybe CredPair -> (Maybe UUID, R.RemoteConfig) -> Annex RemoteName
+setupSpecialRemote = setupSpecialRemote' True
+
+setupSpecialRemote' :: Bool -> RemoteName -> RemoteType -> R.RemoteConfig -> Maybe CredPair -> (Maybe UUID, R.RemoteConfig) -> Annex RemoteName
+setupSpecialRemote' setdesc name remotetype config mcreds (mu, c) = do
+	{- Currently, only 'weak' ciphers can be generated from the
+	 - assistant, because otherwise GnuPG may block once the entropy
+	 - pool is drained, and as of now there's no way to tell the user
+	 - to perform IO actions to refill the pool. -}
+	(c', u) <- R.setup remotetype mu mcreds $
+		M.insert "highRandomQuality" "false" $ M.union config c
+	configSet u c'
+	when setdesc $
+		whenM (isNothing . M.lookup u <$> uuidMap) $
+			describeUUID u name
+	return name
+
+{- Returns the name of the git remote it created. If there's already a
+ - remote at the location, returns its name. -}
+makeGitRemote :: String -> String -> Annex RemoteName
+makeGitRemote basename location = makeRemote basename location $ \name ->
+	void $ inRepo $ Git.Command.runBool
+		[Param "remote", Param "add", Param name, Param location]
+
+{- If there's not already a remote at the location, adds it using the
+ - action, which is passed the name of the remote to make.
+ -
+ - Returns the name of the remote. -}
+makeRemote :: String -> String -> (RemoteName -> Annex ()) -> Annex RemoteName
+makeRemote basename location a = do
+	g <- gitRepo
+	if not (any samelocation $ Git.remotes g)
+		then do
+			let name = uniqueRemoteName basename 0 g
+			a name
+			return name
+		else return basename
+  where
+	samelocation x = Git.repoLocation x == location
+
+{- Generate an unused name for a remote, adding a number if
+ - necessary.
+ -
+ - Ensures that the returned name is a legal git remote name. -}
+uniqueRemoteName :: String -> Int -> Git.Repo -> RemoteName
+uniqueRemoteName basename n r
+	| null namecollision = name
+	| otherwise = uniqueRemoteName legalbasename (succ n) r
+  where
+	namecollision = filter samename (Git.remotes r)
+	samename x = Git.remoteName x == Just name
+	name
+		| n == 0 = legalbasename
+		| otherwise = legalbasename ++ show n
+	legalbasename = makeLegalName basename
+
+{- Finds a CredPair belonging to any Remote that is of a given type
+ - and matches some other criteria.
+ -
+ - This can be used as a default when another repository is being set up
+ - using the same service.
+ -
+ - A function must be provided that returns the CredPairStorage
+ - to use for a particular Remote's uuid.
+ -}
+previouslyUsedCredPair
+	:: (UUID -> CredPairStorage)
+	-> RemoteType
+	-> (Remote -> Bool)
+	-> Annex (Maybe CredPair)
+previouslyUsedCredPair getstorage remotetype criteria =
+	getM fromstorage =<< filter criteria . filter sametype <$> remoteList
+  where
+	sametype r = R.typename (R.remotetype r) == R.typename remotetype
+	fromstorage r = do
+		let storage = getstorage (R.uuid r)
+		getRemoteCredPair (R.config r) storage

Assistant/Monad.hs

@@ -0,0 +1,150 @@
+{- git-annex assistant monad
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE GeneralizedNewtypeDeriving, MultiParamTypeClasses #-}
+
+module Assistant.Monad (
+	Assistant,
+	AssistantData(..),
+	newAssistantData,
+	runAssistant,
+	getAssistant,
+	LiftAnnex,
+	liftAnnex,
+	(<~>),
+	(<<~),
+	asIO,
+	asIO1,
+	asIO2,
+	ThreadName,
+	debug,
+	notice
+) where
+
+import "mtl" Control.Monad.Reader
+import System.Log.Logger
+
+import Common.Annex
+import Assistant.Types.ThreadedMonad
+import Assistant.Types.DaemonStatus
+import Assistant.Types.ScanRemotes
+import Assistant.Types.TransferQueue
+import Assistant.Types.TransferSlots
+import Assistant.Types.TransferrerPool
+import Assistant.Types.Pushes
+import Assistant.Types.BranchChange
+import Assistant.Types.Commits
+import Assistant.Types.Changes
+import Assistant.Types.RepoProblem
+import Assistant.Types.Buddies
+import Assistant.Types.NetMessager
+import Assistant.Types.ThreadName
+import Assistant.Types.RemoteControl
+import Assistant.Types.CredPairCache
+
+newtype Assistant a = Assistant { mkAssistant :: ReaderT AssistantData IO a }
+	deriving (
+		Monad,
+		MonadIO,
+		MonadReader AssistantData,
+		Functor,
+		Applicative
+	)
+
+data AssistantData = AssistantData
+	{ threadName :: ThreadName
+	, threadState :: ThreadState
+	, daemonStatusHandle :: DaemonStatusHandle
+	, scanRemoteMap :: ScanRemoteMap
+	, transferQueue :: TransferQueue
+	, transferSlots :: TransferSlots
+	, transferrerPool :: TransferrerPool
+	, failedPushMap :: FailedPushMap
+	, commitChan :: CommitChan
+	, changePool :: ChangePool
+	, repoProblemChan :: RepoProblemChan
+	, branchChangeHandle :: BranchChangeHandle
+	, buddyList :: BuddyList
+	, netMessager :: NetMessager
+	, remoteControl :: RemoteControl
+	, credPairCache :: CredPairCache
+	}
+
+newAssistantData :: ThreadState -> DaemonStatusHandle -> IO AssistantData
+newAssistantData st dstatus = AssistantData
+	<$> pure (ThreadName "main")
+	<*> pure st
+	<*> pure dstatus
+	<*> newScanRemoteMap
+	<*> newTransferQueue
+	<*> newTransferSlots
+	<*> newTransferrerPool (checkNetworkConnections dstatus)
+	<*> newFailedPushMap
+	<*> newCommitChan
+	<*> newChangePool
+	<*> newRepoProblemChan
+	<*> newBranchChangeHandle
+	<*> newBuddyList
+	<*> newNetMessager
+	<*> newRemoteControl
+	<*> newCredPairCache
+
+runAssistant :: AssistantData -> Assistant a -> IO a
+runAssistant d a = runReaderT (mkAssistant a) d
+
+getAssistant :: (AssistantData -> a) -> Assistant a
+getAssistant = reader
+
+{- Using a type class for lifting into the annex monad allows
+ - easily lifting to it from multiple different monads. -}
+class LiftAnnex m where
+	liftAnnex :: Annex a -> m a
+
+{- Runs an action in the git-annex monad. Note that the same monad state
+ - is shared among all assistant threads, so only one of these can run at
+ - a time. Therefore, long-duration actions should be avoided. -}
+instance LiftAnnex Assistant where
+	liftAnnex a = do
+		st <- reader threadState
+		liftIO $ runThreadState st a
+
+{- Runs an IO action, passing it an IO action that runs an Assistant action. -}
+(<~>) :: (IO a -> IO b) -> Assistant a -> Assistant b
+io <~> a = do
+	d <- reader id
+	liftIO $ io $ runAssistant d a
+
+{- Creates an IO action that will run an Assistant action when run. -}
+asIO :: Assistant a -> Assistant (IO a)
+asIO a = do
+	d <- reader id
+	return $ runAssistant d a
+
+asIO1 :: (a -> Assistant b) -> Assistant (a -> IO b)
+asIO1 a = do
+	d <- reader id
+	return $ \v -> runAssistant d $ a v
+
+asIO2 :: (a -> b -> Assistant c) -> Assistant (a -> b -> IO c)
+asIO2 a = do
+	d <- reader id
+	return $ \v1 v2 -> runAssistant d (a v1 v2)
+
+{- Runs an IO action on a selected field of the AssistantData. -}
+(<<~) :: (a -> IO b) -> (AssistantData -> a) -> Assistant b
+io <<~ v = reader v >>= liftIO . io
+
+debug :: [String] -> Assistant ()
+debug = logaction debugM
+
+notice :: [String] -> Assistant ()
+notice = logaction noticeM
+
+logaction :: (String -> String -> IO ()) -> [String] -> Assistant ()
+logaction a ws = do
+	ThreadName name <- getAssistant threadName
+	liftIO $ a name $ unwords $ (name ++ ":") : ws

Assistant/NamedThread.hs

@@ -0,0 +1,102 @@
+{- git-annex assistant named threads.
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Assistant.NamedThread where
+
+import Common.Annex
+import Assistant.Types.NamedThread
+import Assistant.Types.ThreadName
+import Assistant.Types.DaemonStatus
+import Assistant.Types.UrlRenderer
+import Assistant.DaemonStatus
+import Assistant.Monad
+import Utility.NotificationBroadcaster
+
+import Control.Concurrent
+import Control.Concurrent.Async
+import qualified Data.Map as M
+import qualified Control.Exception as E
+
+#ifdef WITH_WEBAPP
+import Assistant.WebApp.Types
+import Assistant.Types.Alert
+import Assistant.Alert
+import qualified Data.Text as T
+#endif
+
+{- Starts a named thread, if it's not already running.
+ -
+ - Named threads are run by a management thread, so if they crash
+ - an alert is displayed, allowing the thread to be restarted. -}
+startNamedThread :: UrlRenderer -> NamedThread -> Assistant ()
+startNamedThread urlrenderer (NamedThread afterstartupsanitycheck name a) = do
+	m <- startedThreads <$> getDaemonStatus
+	case M.lookup name m of
+		Nothing -> start
+		Just (aid, _) -> do
+			r <- liftIO (E.try (poll aid) :: IO (Either E.SomeException (Maybe (Either E.SomeException ()))))
+			case r of
+				Right Nothing -> noop
+				_ -> start
+  where
+	start
+		| afterstartupsanitycheck = do
+			status <- getDaemonStatus
+			h <- liftIO $ newNotificationHandle False $
+				startupSanityCheckNotifier status
+			startwith $ runmanaged $
+				liftIO $ waitNotification h
+		| otherwise = startwith $ runmanaged noop
+	startwith runner = do
+		d <- getAssistant id
+		aid <- liftIO $ runner $ d { threadName = name }
+		restart <- asIO $ startNamedThread urlrenderer (NamedThread False name a)
+		modifyDaemonStatus_ $ \s -> s
+			{ startedThreads = M.insertWith' const name (aid, restart) (startedThreads s) }
+	runmanaged first d = do
+		aid <- async $ runAssistant d $ do
+			void first
+			a
+		void $ forkIO $ manager d aid
+		return aid
+	manager d aid = do
+		r <- E.try (wait aid) :: IO (Either E.SomeException ())
+		case r of
+			Right _ -> noop
+			Left e -> do
+				let msg = unwords
+					[ fromThreadName $ threadName d
+					, "crashed:", show e
+					]
+				hPutStrLn stderr msg
+#ifdef WITH_WEBAPP
+				button <- runAssistant d $ mkAlertButton True
+					(T.pack "Restart Thread")
+					urlrenderer 
+					(RestartThreadR name)
+				runAssistant d $ void $ addAlert $
+					(warningAlert (fromThreadName name) msg)
+						{ alertButtons = [button] }
+#endif
+
+namedThreadId :: NamedThread -> Assistant (Maybe ThreadId)
+namedThreadId (NamedThread _ name _) = do
+	m <- startedThreads <$> getDaemonStatus
+	return $ asyncThreadId . fst <$> M.lookup name m
+
+{- Waits for all named threads that have been started to finish.
+ -
+ - Note that if a named thread crashes, it will probably
+ - cause this to crash as well. Also, named threads that are started
+ - after this is called will not be waited on. -}
+waitNamedThreads :: Assistant ()
+waitNamedThreads = do
+	m <- startedThreads <$> getDaemonStatus
+	liftIO $ mapM_ (wait . fst) $ M.elems m
+

Assistant/NetMessager.hs

@@ -0,0 +1,180 @@
+{- git-annex assistant out of band network messager interface
+ -
+ - Copyright 2012-2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE BangPatterns #-}
+
+module Assistant.NetMessager where
+
+import Assistant.Common
+import Assistant.Types.NetMessager
+
+import Control.Concurrent.STM
+import Control.Concurrent.MSampleVar
+import qualified Data.Set as S
+import qualified Data.Map as M
+import qualified Data.DList as D
+
+sendNetMessage :: NetMessage -> Assistant ()
+sendNetMessage m = 
+	(atomically . flip writeTChan m) <<~ (netMessages . netMessager)
+
+waitNetMessage :: Assistant (NetMessage)
+waitNetMessage = (atomically . readTChan) <<~ (netMessages . netMessager)
+
+notifyNetMessagerRestart :: Assistant ()
+notifyNetMessagerRestart =
+	flip writeSV () <<~ (netMessagerRestart . netMessager)
+
+{- This can be used to get an early indication if the network has
+ - changed, to immediately restart a connection. However, that is not
+ - available on all systems, so clients also need to deal with
+ - restarting dropped connections in the usual way. -}
+waitNetMessagerRestart :: Assistant ()
+waitNetMessagerRestart = readSV <<~ (netMessagerRestart . netMessager)
+
+{- Store a new important NetMessage for a client, and if an equivilant
+ - older message is already stored, remove it from both importantNetMessages
+ - and sentImportantNetMessages. -}
+storeImportantNetMessage :: NetMessage -> ClientID -> (ClientID -> Bool) -> Assistant ()
+storeImportantNetMessage m client matchingclient = go <<~ netMessager
+  where
+	go nm = atomically $ do
+		q <- takeTMVar $ importantNetMessages nm
+		sent <- takeTMVar $ sentImportantNetMessages nm
+		putTMVar (importantNetMessages nm) $
+			M.alter (Just . maybe (S.singleton m) (S.insert m)) client $
+				M.mapWithKey removematching q
+		putTMVar (sentImportantNetMessages nm) $
+			M.mapWithKey removematching sent
+	removematching someclient s
+		| matchingclient someclient = S.filter (not . equivilantImportantNetMessages m) s
+		| otherwise = s
+
+{- Indicates that an important NetMessage has been sent to a client. -}
+sentImportantNetMessage :: NetMessage -> ClientID -> Assistant ()
+sentImportantNetMessage m client = go <<~ (sentImportantNetMessages . netMessager)
+  where
+	go v = atomically $ do
+		sent <- takeTMVar v
+		putTMVar v $
+			M.alter (Just . maybe (S.singleton m) (S.insert m)) client sent
+
+{- Checks for important NetMessages that have been stored for a client, and
+ - sent to a client. Typically the same client for both, although 
+ - a modified or more specific client may need to be used. -}
+checkImportantNetMessages :: (ClientID, ClientID) -> Assistant (S.Set NetMessage, S.Set NetMessage)
+checkImportantNetMessages (storedclient, sentclient) = go <<~ netMessager
+  where
+	go nm = atomically $ do
+		stored <- M.lookup storedclient <$> (readTMVar $ importantNetMessages nm)
+		sent <- M.lookup sentclient <$> (readTMVar $ sentImportantNetMessages nm)
+		return (fromMaybe S.empty stored, fromMaybe S.empty sent)
+
+{- Queues a push initiation message in the queue for the appropriate
+ - side of the push but only if there is not already an initiation message
+ - from the same client in the queue. -}
+queuePushInitiation :: NetMessage -> Assistant ()
+queuePushInitiation msg@(Pushing clientid stage) = do
+	tv <- getPushInitiationQueue side
+	liftIO $ atomically $ do
+		r <- tryTakeTMVar tv
+		case r of
+			Nothing -> putTMVar tv [msg]
+			Just l -> do
+				let !l' = msg : filter differentclient l
+				putTMVar tv l'
+  where
+	side = pushDestinationSide stage
+	differentclient (Pushing cid _) = cid /= clientid
+	differentclient _ = True
+queuePushInitiation _ = noop
+
+{- Waits for a push inititation message to be received, and runs
+ - function to select a message from the queue. -}
+waitPushInitiation :: PushSide -> ([NetMessage] -> (NetMessage, [NetMessage])) -> Assistant NetMessage
+waitPushInitiation side selector = do
+	tv <- getPushInitiationQueue side
+	liftIO $ atomically $ do
+		q <- takeTMVar tv
+		if null q
+			then retry
+			else do
+				let (msg, !q') = selector q
+				unless (null q') $
+					putTMVar tv q'
+				return msg
+
+{- Stores messages for a push into the appropriate inbox.
+ -
+ - To avoid overflow, only 1000 messages max are stored in any
+ - inbox, which should be far more than necessary.
+ -
+ - TODO: If we have more than 100 inboxes for different clients,
+ - discard old ones that are not currently being used by any push.
+ -}
+storeInbox :: NetMessage -> Assistant ()
+storeInbox msg@(Pushing clientid stage) = do
+	inboxes <- getInboxes side
+	stored <- liftIO $ atomically $ do
+		m <- readTVar inboxes
+		let update = \v -> do
+			writeTVar inboxes $
+				M.insertWith' const clientid v m
+			return True
+		case M.lookup clientid m of
+			Nothing -> update (1, tostore)
+			Just (sz, l)
+				| sz > 1000 -> return False
+				| otherwise ->
+					let !sz' = sz + 1
+					    !l' = D.append l tostore
+					in update (sz', l')
+	if stored
+		then netMessagerDebug clientid ["stored", logNetMessage msg, "in", show side, "inbox"]
+		else netMessagerDebug clientid ["discarded", logNetMessage msg, "; ", show side, "inbox is full"]
+  where
+	side = pushDestinationSide stage
+	tostore = D.singleton msg
+storeInbox _ = noop
+
+{- Gets the new message for a push from its inbox.
+ - Blocks until a message has been received. -}
+waitInbox :: ClientID -> PushSide -> Assistant (NetMessage)
+waitInbox clientid side = do
+	inboxes <- getInboxes side
+	liftIO $ atomically $ do
+		m <- readTVar inboxes
+		case M.lookup clientid m of
+			Nothing -> retry
+			Just (sz, dl)
+				| sz < 1 -> retry
+				| otherwise -> do
+					let msg = D.head dl
+					let dl' = D.tail dl
+					let !sz' = sz - 1
+					writeTVar inboxes $
+						M.insertWith' const clientid (sz', dl') m
+					return msg
+
+emptyInbox :: ClientID -> PushSide -> Assistant ()
+emptyInbox clientid side = do
+	inboxes <- getInboxes side
+	liftIO $ atomically $
+		modifyTVar' inboxes $
+			M.delete clientid
+	
+getInboxes :: PushSide -> Assistant Inboxes
+getInboxes side =
+	getSide side . netMessagerInboxes <$> getAssistant netMessager
+
+getPushInitiationQueue :: PushSide -> Assistant (TMVar [NetMessage])
+getPushInitiationQueue side =
+	getSide side . netMessagerPushInitiations <$> getAssistant netMessager
+
+netMessagerDebug :: ClientID -> [String] -> Assistant ()
+netMessagerDebug clientid l = debug $
+	"NetMessager" : l ++ [show $ logClientID clientid]

Assistant/Pairing.hs

@@ -0,0 +1,101 @@
+{- git-annex assistant repo pairing, core data types
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Assistant.Pairing where
+
+import Common.Annex
+import Utility.Verifiable
+import Assistant.Ssh
+
+import Control.Concurrent
+import Network.Socket
+import Data.Char
+import qualified Data.Text as T
+
+data PairStage
+	{- "I'll pair with anybody who shares the secret that can be used
+	 - to verify this request." -}
+	 = PairReq
+	{- "I've verified your request, and you can verify this to see
+	 - that I know the secret. I set up your ssh key already.
+	 - Here's mine for you to set up." -}
+	| PairAck
+	{- "I saw your PairAck; you can stop sending them." -}
+	| PairDone
+	deriving (Eq, Read, Show, Ord, Enum)
+
+newtype PairMsg = PairMsg (Verifiable (PairStage, PairData, SomeAddr))
+	deriving (Eq, Read, Show)
+
+verifiedPairMsg :: PairMsg -> PairingInProgress -> Bool
+verifiedPairMsg (PairMsg m) pip = verify m $ inProgressSecret pip
+
+fromPairMsg :: PairMsg -> Verifiable (PairStage, PairData, SomeAddr)
+fromPairMsg (PairMsg m) = m
+
+pairMsgStage :: PairMsg -> PairStage
+pairMsgStage (PairMsg (Verifiable (s, _, _) _)) = s
+
+pairMsgData :: PairMsg -> PairData
+pairMsgData (PairMsg (Verifiable (_, d, _) _)) = d
+
+pairMsgAddr :: PairMsg -> SomeAddr
+pairMsgAddr (PairMsg (Verifiable (_, _, a) _)) = a
+
+data PairData = PairData
+	-- uname -n output, not a full domain name
+	{ remoteHostName :: Maybe HostName
+	, remoteUserName :: UserName
+	, remoteDirectory :: FilePath
+	, remoteSshPubKey :: SshPubKey
+	, pairUUID :: UUID
+	}
+	deriving (Eq, Read, Show)
+
+checkSane :: PairData -> Bool
+checkSane p = all (not . any isControl)
+	[ fromMaybe "" (remoteHostName p)
+	, remoteUserName p
+	, remoteDirectory p
+	, remoteSshPubKey p
+	, fromUUID (pairUUID p)
+	]
+
+type UserName = String
+
+{- A pairing that is in progress has a secret, a thread that is
+ - broadcasting pairing messages, and a SshKeyPair that has not yet been
+ - set up on disk. -}
+data PairingInProgress = PairingInProgress
+	{ inProgressSecret :: Secret
+	, inProgressThreadId :: Maybe ThreadId
+	, inProgressSshKeyPair :: SshKeyPair
+	, inProgressPairData :: PairData
+	, inProgressPairStage :: PairStage
+	}
+	deriving (Show)
+
+data SomeAddr = IPv4Addr HostAddress
+{- My Android build of the Network library does not currently have IPV6
+ - support. -}
+#ifndef __ANDROID__
+	| IPv6Addr HostAddress6
+#endif
+	deriving (Ord, Eq, Read, Show)
+
+{- This contains the whole secret, just lightly obfuscated to make it not
+ - too obvious. It's only displayed in the user's web browser. -}
+newtype SecretReminder = SecretReminder [Int]
+	deriving (Show, Eq, Ord, Read)
+
+toSecretReminder :: T.Text -> SecretReminder
+toSecretReminder = SecretReminder . map ord . T.unpack
+
+fromSecretReminder :: SecretReminder -> T.Text
+fromSecretReminder (SecretReminder s) = T.pack $ map chr s

Assistant/Pairing/MakeRemote.hs

@@ -0,0 +1,95 @@
+{- git-annex assistant pairing remote creation
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.Pairing.MakeRemote where
+
+import Assistant.Common
+import Assistant.Ssh
+import Assistant.Pairing
+import Assistant.Pairing.Network
+import Assistant.MakeRemote
+import Assistant.Sync
+import Config.Cost
+import Config
+import qualified Types.Remote as Remote
+
+import Network.Socket
+import qualified Data.Text as T
+
+{- Authorized keys are set up before pairing is complete, so that the other
+ - side can immediately begin syncing. -}
+setupAuthorizedKeys :: PairMsg -> FilePath -> IO ()
+setupAuthorizedKeys msg repodir = case validateSshPubKey $ remoteSshPubKey $ pairMsgData msg of
+	Left err -> error err
+	Right pubkey -> 
+		unlessM (liftIO $ addAuthorizedKeys True repodir pubkey) $
+			error "failed setting up ssh authorized keys"
+
+{- When local pairing is complete, this is used to set up the remote for
+ - the host we paired with. -}
+finishedLocalPairing :: PairMsg -> SshKeyPair -> Assistant ()
+finishedLocalPairing msg keypair = do
+	sshdata <- liftIO $ setupSshKeyPair keypair =<< pairMsgToSshData msg
+	{- Ensure that we know the ssh host key for the host we paired with.
+	 - If we don't, ssh over to get it. -}
+	liftIO $ unlessM (knownHost $ sshHostName sshdata) $
+		void $ sshTranscript
+			[ sshOpt "StrictHostKeyChecking" "no"
+			, sshOpt "NumberOfPasswordPrompts" "0"
+			, "-n"
+			, genSshHost (sshHostName sshdata) (sshUserName sshdata)
+			, "git-annex-shell -c configlist " ++ T.unpack (sshDirectory sshdata)
+			]
+			Nothing
+	r <- liftAnnex $ addRemote $ makeSshRemote sshdata
+	liftAnnex $ setRemoteCost (Remote.repo r) semiExpensiveRemoteCost
+	syncRemote r
+
+{- Mostly a straightforward conversion.  Except:
+ -  * Determine the best hostname to use to contact the host.
+ -  * Strip leading ~/ from the directory name.
+ -}
+pairMsgToSshData :: PairMsg -> IO SshData
+pairMsgToSshData msg = do
+	let d = pairMsgData msg
+	hostname <- liftIO $ bestHostName msg
+	let dir = case remoteDirectory d of
+		('~':'/':v) -> v
+		v -> v
+	return SshData
+		{ sshHostName = T.pack hostname
+		, sshUserName = Just (T.pack $ remoteUserName d)
+		, sshDirectory = T.pack dir
+		, sshRepoName = genSshRepoName hostname dir
+		, sshPort = 22
+		, needsPubKey = True
+		, sshCapabilities = [GitAnnexShellCapable, GitCapable, RsyncCapable]
+		}
+
+{- Finds the best hostname to use for the host that sent the PairMsg.
+ -
+ - If remoteHostName is set, tries to use a .local address based on it.
+ - That's the most robust, if this system supports .local.
+ - Otherwise, looks up the hostname in the DNS for the remoteAddress,
+ - if any. May fall back to remoteAddress if there's no DNS. Ugh. -}
+bestHostName :: PairMsg -> IO HostName
+bestHostName msg = case remoteHostName $ pairMsgData msg of
+	Just h -> do
+		let localname = h ++ ".local"
+		addrs <- catchDefaultIO [] $
+			getAddrInfo Nothing (Just localname) Nothing
+		maybe fallback (const $ return localname) (headMaybe addrs)
+	Nothing -> fallback
+  where
+	fallback = do
+		let a = pairMsgAddr msg
+		let sockaddr = case a of
+			IPv4Addr addr -> SockAddrInet (PortNum 0) addr
+			IPv6Addr addr -> SockAddrInet6 (PortNum 0) 0 addr 0
+		fromMaybe (showAddr a)
+			<$> catchDefaultIO Nothing
+				(fst <$> getNameInfo [] True False sockaddr)

Assistant/Pairing/Network.hs

@@ -0,0 +1,129 @@
+{- git-annex assistant pairing network code
+ -
+ - All network traffic is sent over multicast UDP. For reliability,
+ - each message is repeated until acknowledged. This is done using a
+ - thread, that gets stopped before the next message is sent.
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.Pairing.Network where
+
+import Assistant.Common
+import Assistant.Pairing
+import Assistant.DaemonStatus
+import Utility.ThreadScheduler
+import Utility.Verifiable
+
+import Network.Multicast
+import Network.Info
+import Network.Socket
+import qualified Data.Map as M
+import Control.Concurrent
+
+{- This is an arbitrary port in the dynamic port range, that could
+ - conceivably be used for some other broadcast messages.
+ - If so, hope they ignore the garbage from us; we'll certianly
+ - ignore garbage from them. Wild wild west. -}
+pairingPort :: PortNumber
+pairingPort = 55556
+
+{- Goal: Reach all hosts on the same network segment.
+ - Method: Use same address that avahi uses. Other broadcast addresses seem
+ - to not be let through some routers. -}
+multicastAddress :: SomeAddr -> HostName
+multicastAddress (IPv4Addr _) = "224.0.0.251"
+multicastAddress (IPv6Addr _) = "ff02::fb"
+
+{- Multicasts a message repeatedly on all interfaces, with a 2 second
+ - delay between each transmission. The message is repeated forever
+ - unless a number of repeats is specified.
+ -
+ - The remoteHostAddress is set to the interface's IP address.
+ -
+ - Note that new sockets are opened each time. This is hardly efficient,
+ - but it allows new network interfaces to be used as they come up.
+ - On the other hand, the expensive DNS lookups are cached.
+ -}
+multicastPairMsg :: Maybe Int -> Secret -> PairData -> PairStage -> IO ()
+multicastPairMsg repeats secret pairdata stage = go M.empty repeats
+  where
+	go _ (Just 0) = noop
+	go cache n = do
+		addrs <- activeNetworkAddresses
+		let cache' = updatecache cache addrs
+		mapM_ (sendinterface cache') addrs
+		threadDelaySeconds (Seconds 2)
+		go cache' $ pred <$> n
+	{- The multicast library currently chokes on ipv6 addresses. -}
+	sendinterface _ (IPv6Addr _) = noop
+	sendinterface cache i = void $ tryIO $
+		withSocketsDo $ bracket setup cleanup use
+	  where
+		setup = multicastSender (multicastAddress i) pairingPort
+		cleanup (sock, _) = sClose sock -- FIXME does not work
+		use (sock, addr) = do
+			setInterface sock (showAddr i)
+			maybe noop (\s -> void $ sendTo sock s addr)
+				(M.lookup i cache)
+	updatecache cache [] = cache
+	updatecache cache (i:is)
+		| M.member i cache = updatecache cache is
+		| otherwise = updatecache (M.insert i (show $ mkmsg i) cache) is
+	mkmsg addr = PairMsg $
+		mkVerifiable (stage, pairdata, addr) secret
+
+startSending :: PairingInProgress -> PairStage -> (PairStage -> IO ()) -> Assistant ()
+startSending pip stage sender = do
+	a <- asIO start
+	void $ liftIO $ forkIO a
+  where
+	start = do
+		tid <- liftIO myThreadId
+		let pip' = pip { inProgressPairStage = stage, inProgressThreadId = Just tid }
+		oldpip <- modifyDaemonStatus $
+			\s -> (s { pairingInProgress = Just pip' }, pairingInProgress s)
+		maybe noop stopold oldpip
+		liftIO $ sender stage
+	stopold = maybe noop (liftIO . killThread) . inProgressThreadId
+
+stopSending :: PairingInProgress -> Assistant ()
+stopSending pip = do
+	maybe noop (liftIO . killThread) $ inProgressThreadId pip
+	modifyDaemonStatus_ $ \s -> s { pairingInProgress = Nothing }
+
+class ToSomeAddr a where
+	toSomeAddr :: a -> SomeAddr
+
+instance ToSomeAddr IPv4 where
+	toSomeAddr (IPv4 a) = IPv4Addr a
+
+instance ToSomeAddr IPv6 where
+	toSomeAddr (IPv6 o1 o2 o3 o4) = IPv6Addr (o1, o2, o3, o4)
+
+showAddr :: SomeAddr -> HostName
+showAddr (IPv4Addr a) = show $ IPv4 a
+showAddr (IPv6Addr (o1, o2, o3, o4)) = show $ IPv6 o1 o2 o3 o4
+
+activeNetworkAddresses :: IO [SomeAddr]
+activeNetworkAddresses = filter (not . all (`elem` "0.:") . showAddr)
+	. concatMap (\ni -> [toSomeAddr $ ipv4 ni, toSomeAddr $ ipv6 ni])
+	<$> getNetworkInterfaces
+
+{- A human-visible description of the repository being paired with.
+ - Note that the repository's description is not shown to the user, because
+ - it could be something like "my repo", which is confusing when pairing
+ - with someone else's repo. However, this has the same format as the
+ - default decription of a repo. -}
+pairRepo :: PairMsg -> String
+pairRepo msg = concat
+	[ remoteUserName d
+	, "@"
+	, fromMaybe (showAddr $ pairMsgAddr msg) (remoteHostName d)
+	, ":"
+	, remoteDirectory d
+	]
+  where
+	d = pairMsgData msg

Assistant/Pushes.hs

@@ -0,0 +1,40 @@
+{- git-annex assistant push tracking
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.Pushes where
+
+import Assistant.Common
+import Assistant.Types.Pushes
+
+import Control.Concurrent.STM
+import Data.Time.Clock
+import qualified Data.Map as M
+
+{- Blocks until there are failed pushes.
+ - Returns Remotes whose pushes failed a given time duration or more ago.
+ - (This may be an empty list.) -}
+getFailedPushesBefore :: NominalDiffTime -> Assistant [Remote]
+getFailedPushesBefore duration = do
+	v <- getAssistant failedPushMap
+	liftIO $ do
+		m <- atomically $ readTMVar v
+		now <- getCurrentTime
+		return $ M.keys $ M.filter (not . toorecent now) m
+  where
+	toorecent now time = now `diffUTCTime` time < duration
+
+{- Modifies the map. -}
+changeFailedPushMap :: (PushMap -> PushMap) -> Assistant ()
+changeFailedPushMap a = do
+	v <- getAssistant failedPushMap
+	liftIO $ atomically $ store v . a . fromMaybe M.empty =<< tryTakeTMVar v
+  where
+	{- tryTakeTMVar empties the TMVar; refill it only if
+	 - the modified map is not itself empty -}
+	store v m
+		| m == M.empty = noop
+		| otherwise = putTMVar v $! m

Assistant/RemoteControl.hs

@@ -0,0 +1,21 @@
+{- git-annex assistant RemoteDaemon control
+ -
+ - Copyright 2014 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.RemoteControl (
+	sendRemoteControl,
+	RemoteDaemon.Consumed(..)
+) where
+
+import Assistant.Common
+import qualified RemoteDaemon.Types as RemoteDaemon
+
+import Control.Concurrent
+
+sendRemoteControl :: RemoteDaemon.Consumed -> Assistant ()
+sendRemoteControl msg = do
+	clicker <- getAssistant remoteControl
+	liftIO $ writeChan clicker msg

Assistant/Repair.hs

@@ -0,0 +1,159 @@
+{- git-annex assistant repository repair
+ -
+ - Copyright 2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU AGPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Assistant.Repair where
+
+import Assistant.Common
+import Command.Repair (repairAnnexBranch, trackingOrSyncBranch)
+import Git.Fsck (FsckResults, foundBroken)
+import Git.Repair (runRepairOf)
+import qualified Git
+import qualified Remote
+import qualified Types.Remote as Remote
+import Logs.FsckResults
+import Annex.UUID
+import Utility.Batch
+import Config.Files
+import Assistant.Sync
+import Assistant.Alert
+import Assistant.DaemonStatus
+import Assistant.Types.UrlRenderer
+#ifdef WITH_WEBAPP
+import Assistant.WebApp.Types
+import qualified Data.Text as T
+#endif
+import qualified Utility.Lsof as Lsof
+import Utility.ThreadScheduler
+
+import Control.Concurrent.Async
+
+{- When the FsckResults require a repair, tries to do a non-destructive
+ - repair. If that fails, pops up an alert. -}
+repairWhenNecessary :: UrlRenderer -> UUID -> Maybe Remote -> FsckResults -> Assistant Bool
+repairWhenNecessary urlrenderer u mrmt fsckresults
+	| foundBroken fsckresults = do
+		liftAnnex $ writeFsckResults u fsckresults
+		repodesc <- liftAnnex $ Remote.prettyUUID u
+		ok <- alertWhile (repairingAlert repodesc)
+			(runRepair u mrmt False)
+#ifdef WITH_WEBAPP
+		unless ok $ do
+			button <- mkAlertButton True (T.pack "Click Here") urlrenderer $
+				RepairRepositoryR u
+			void $ addAlert $ brokenRepositoryAlert [button]
+#endif
+		return ok
+	| otherwise = return False
+
+runRepair :: UUID -> Maybe Remote -> Bool -> Assistant Bool
+runRepair u mrmt destructiverepair = do
+	fsckresults <- liftAnnex $ readFsckResults u
+	myu <- liftAnnex getUUID
+	ok <- if u == myu
+		then localrepair fsckresults
+		else remoterepair fsckresults
+	liftAnnex $ clearFsckResults u
+	debug [ "Repaired", show u, show ok ]
+
+	return ok
+  where
+	localrepair fsckresults = do
+		-- Stop the watcher from running while running repairs.
+		changeSyncable Nothing False
+
+		-- This intentionally runs the repair inside the Annex
+		-- monad, which is not strictly necessary, but keeps
+		-- other threads that might be trying to use the Annex
+		-- from running until it completes.
+		ok <- liftAnnex $ repair fsckresults Nothing
+
+		-- Run a background fast fsck if a destructive repair had
+		-- to be done, to ensure that the git-annex branch
+		-- reflects the current state of the repo.
+		when destructiverepair $
+			backgroundfsck [ Param "--fast" ]
+
+		-- Start the watcher running again. This also triggers it to
+		-- do a startup scan, which is especially important if the
+		-- git repo repair removed files from the index file. Those
+		-- files will be seen as new, and re-added to the repository.
+		when (ok || destructiverepair) $
+			changeSyncable Nothing True
+
+		return ok
+
+	remoterepair fsckresults = case Remote.repairRepo =<< mrmt of
+		Nothing -> return False
+		Just mkrepair -> do
+			thisrepopath <- liftIO . absPath
+				=<< liftAnnex (fromRepo Git.repoPath)
+			a <- liftAnnex $ mkrepair $
+				repair fsckresults (Just thisrepopath)
+			liftIO $ catchBoolIO a
+
+	repair fsckresults referencerepo = do
+		(ok, modifiedbranches) <- inRepo $
+			runRepairOf fsckresults trackingOrSyncBranch destructiverepair referencerepo
+		when destructiverepair $
+			repairAnnexBranch modifiedbranches
+		return ok
+	
+	backgroundfsck params = liftIO $ void $ async $ do
+		program <- readProgramFile
+		batchCommand program (Param "fsck" : params)
+
+{- Detect when a git lock file exists and has no git process currently
+ - writing to it. This strongly suggests it is a stale lock file.
+ -
+ - However, this could be on a network filesystem. Which is not very safe
+ - anyway (the assistant relies on being able to check when files have
+ - no writers to know when to commit them). Also, a few lock-file-ish
+ - things used by git are not kept open, particularly MERGE_HEAD.
+ -
+ - So, just in case, when the lock file appears stale, we delay for one
+ - minute, and check its size. If the size changed, delay for another
+ - minute, and so on. This will at work to detect when another machine
+ - is writing out a new index file, since git does so by writing the
+ - new content to index.lock.
+ -
+ - Returns true if locks were cleaned up.
+ -}
+repairStaleGitLocks :: Git.Repo -> Assistant Bool
+repairStaleGitLocks r = do
+	lockfiles <- liftIO $ filter islock <$> findgitfiles r
+	repairStaleLocks lockfiles
+	return $ not $ null lockfiles
+  where
+	findgitfiles = dirContentsRecursiveSkipping (== dropTrailingPathSeparator annexDir) True . Git.localGitDir
+	islock f
+		| "gc.pid" `isInfixOf` f = False
+		| ".lock" `isSuffixOf` f = True
+		| takeFileName f == "MERGE_HEAD" = True
+		| otherwise = False
+
+repairStaleLocks :: [FilePath] -> Assistant ()
+repairStaleLocks lockfiles = go =<< getsizes
+  where
+	getsize lf = catchMaybeIO $ (\s -> (lf, s)) <$> getFileSize lf
+	getsizes = liftIO $ catMaybes <$> mapM getsize lockfiles
+	go [] = return ()
+	go l = ifM (liftIO $ null <$> Lsof.query ("--" : map fst l))
+		( do
+			waitforit "to check stale git lock file"
+			l' <- getsizes
+			if l' == l
+				then liftIO $ mapM_ nukeFile (map fst l)
+				else go l'
+		, do
+			waitforit "for git lock file writer"
+			go =<< getsizes
+		)
+	waitforit why = do
+		notice ["Waiting for 60 seconds", why]
+		liftIO $ threadDelaySeconds $ Seconds 60

Assistant/RepoProblem.hs

@@ -0,0 +1,34 @@
+{- git-annex assistant remote problem handling
+ -
+ - Copyright 2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.RepoProblem where
+
+import Assistant.Common
+import Assistant.Types.RepoProblem
+import Utility.TList
+
+import Control.Concurrent.STM
+
+{- Gets all repositories that have problems. Blocks until there is at
+ - least one. -}
+getRepoProblems :: Assistant [RepoProblem]
+getRepoProblems = nubBy sameRepoProblem
+	<$> (atomically . getTList) <<~ repoProblemChan
+
+{- Indicates that there was a problem with a repository, and the problem
+ - appears to not be a transient (eg network connection) problem.
+ -
+ - If the problem is able to be repaired, the passed action will be run.
+ - (However, if multiple problems are reported with a single repository,
+ - only a single action will be run.)
+ -}
+repoHasProblem :: UUID -> Assistant () -> Assistant ()
+repoHasProblem u afterrepair = do
+	rp <- RepoProblem
+		<$> pure u
+		<*> asIO afterrepair
+	(atomically . flip consTList rp) <<~ repoProblemChan

Assistant/Restart.hs

@@ -0,0 +1,117 @@
+{- git-annex assistant restarting
+ -
+ - Copyright 2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU AGPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Assistant.Restart where
+
+import Assistant.Common
+import Assistant.Threads.Watcher
+import Assistant.DaemonStatus
+import Assistant.NamedThread
+import Utility.ThreadScheduler
+import Utility.NotificationBroadcaster
+import Utility.Url
+import Utility.PID
+import qualified Git.Construct
+import qualified Git.Config
+import Config.Files
+import qualified Annex
+import qualified Git
+
+import Control.Concurrent
+#ifndef mingw32_HOST_OS
+import System.Posix (signalProcess, sigTERM)
+#else
+import Utility.WinProcess
+#endif
+import Network.URI
+
+{- Before the assistant can be restarted, have to remove our 
+ - gitAnnexUrlFile and our gitAnnexPidFile. Pausing the watcher is also
+ - a good idea, to avoid fighting when two assistants are running in the
+ - same repo.
+ -}
+prepRestart :: Assistant ()
+prepRestart = do
+	liftIO . maybe noop (`throwTo` PauseWatcher) =<< namedThreadId watchThread
+	liftIO . nukeFile =<< liftAnnex (fromRepo gitAnnexUrlFile)
+	liftIO . nukeFile =<< liftAnnex (fromRepo gitAnnexPidFile)
+
+{- To finish a restart, send a global redirect to the new url
+ - to any web browsers that are displaying the webapp.
+ -
+ - Wait for browser to update before terminating this process. -}
+postRestart :: URLString -> Assistant ()
+postRestart url = do
+	modifyDaemonStatus_ $ \status -> status { globalRedirUrl = Just url }
+	liftIO . sendNotification . globalRedirNotifier =<< getDaemonStatus
+	void $ liftIO $ forkIO $ do
+		threadDelaySeconds (Seconds 120)
+		terminateSelf
+
+terminateSelf :: IO ()
+terminateSelf =
+#ifndef mingw32_HOST_OS
+		signalProcess sigTERM =<< getPID
+#else
+		terminatePID =<< getPID
+#endif
+
+runRestart :: Assistant URLString
+runRestart = liftIO . newAssistantUrl
+	=<< liftAnnex (Git.repoLocation <$> Annex.gitRepo)
+
+{- Starts up the assistant in the repository, and waits for it to create
+ - a gitAnnexUrlFile. Waits for the assistant to be up and listening for
+ - connections by testing the url. -}
+newAssistantUrl :: FilePath -> IO URLString
+newAssistantUrl repo = do
+	startAssistant repo
+	geturl
+  where
+	geturl = do
+		r <- Git.Config.read =<< Git.Construct.fromPath repo
+		waiturl $ gitAnnexUrlFile r
+	waiturl urlfile = do
+		v <- tryIO $ readFile urlfile
+		case v of
+			Left _ -> delayed $ waiturl urlfile
+			Right url -> ifM (assistantListening url)
+				( return url
+				, delayed $ waiturl urlfile
+				)
+	delayed a = do
+		threadDelay 100000 -- 1/10th of a second
+		a
+
+{- Checks if the assistant is listening on an url.
+ -
+ - Always checks http, because https with self-signed cert is problimatic.
+ - warp-tls listens to http, in order to show an error page, so this works.
+ -}
+assistantListening :: URLString -> IO Bool
+assistantListening url = catchBoolIO $ exists url' def
+  where
+	url' = case parseURI url of
+		Nothing -> url
+		Just uri -> show $ uri
+			{ uriScheme = "http:"
+			}
+
+{- Does not wait for assistant to be listening for web connections. 
+ -
+ - On windows, the assistant does not daemonize, which is why the forkIO is
+ - done.
+ -}
+startAssistant :: FilePath -> IO ()
+startAssistant repo = void $ forkIO $ do
+	program <- readProgramFile
+	(_, _, _, pid) <- 
+		createProcess $
+			(proc program ["assistant"]) { cwd = Just repo }
+	void $ checkSuccessProcess pid

Assistant/ScanRemotes.hs

@@ -0,0 +1,41 @@
+{- git-annex assistant remotes needing scanning
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.ScanRemotes where
+
+import Assistant.Common
+import Assistant.Types.ScanRemotes
+import qualified Types.Remote as Remote
+
+import Data.Function
+import Control.Concurrent.STM
+import qualified Data.Map as M
+
+{- Blocks until there is a remote or remotes that need to be scanned.
+ -
+ - The list has higher priority remotes listed first. -}
+getScanRemote :: Assistant [(Remote, ScanInfo)]
+getScanRemote = do
+	v <- getAssistant scanRemoteMap
+	liftIO $ atomically $
+		reverse . sortBy (compare `on` scanPriority . snd) . M.toList
+			<$> takeTMVar v
+
+{- Adds new remotes that need scanning. -}
+addScanRemotes :: Bool -> [Remote] -> Assistant ()
+addScanRemotes _ [] = noop
+addScanRemotes full rs = do
+	v <- getAssistant scanRemoteMap
+	liftIO $ atomically $ do
+		m <- fromMaybe M.empty <$> tryTakeTMVar v
+		putTMVar v $ M.unionWith merge (M.fromList $ zip rs (map info rs)) m
+  where
+	info r = ScanInfo (-1 * Remote.cost r) full
+	merge x y = ScanInfo
+		{ scanPriority = max (scanPriority x) (scanPriority y)
+		, fullScan = fullScan x || fullScan y 
+		}

Assistant/Ssh.hs

@@ -0,0 +1,345 @@
+{- git-annex assistant ssh utilities
+ -
+ - Copyright 2012-2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.Ssh where
+
+import Common.Annex
+import Utility.Tmp
+import Utility.Shell
+import Utility.Rsync
+import Utility.FileMode
+import Utility.SshConfig
+import Git.Remote
+
+import Data.Text (Text)
+import qualified Data.Text as T
+import Data.Char
+import Network.URI
+
+data SshData = SshData
+	{ sshHostName :: Text
+	, sshUserName :: Maybe Text
+	, sshDirectory :: Text
+	, sshRepoName :: String
+	, sshPort :: Int
+	, needsPubKey :: Bool
+	, sshCapabilities :: [SshServerCapability]
+	}
+	deriving (Read, Show, Eq)
+
+data SshServerCapability = GitAnnexShellCapable | GitCapable | RsyncCapable
+	deriving (Read, Show, Eq)
+
+hasCapability :: SshData -> SshServerCapability -> Bool
+hasCapability d c = c `elem` sshCapabilities d
+
+onlyCapability :: SshData -> SshServerCapability -> Bool
+onlyCapability d c = all (== c) (sshCapabilities d)
+
+data SshKeyPair = SshKeyPair
+	{ sshPubKey :: String
+	, sshPrivKey :: String
+	}
+
+instance Show SshKeyPair where
+	show = sshPubKey
+
+type SshPubKey = String
+
+{- ssh -ofoo=bar command-line option -}
+sshOpt :: String -> String -> String
+sshOpt k v = concat ["-o", k, "=", v]
+
+{- user@host or host -}
+genSshHost :: Text -> Maybe Text -> String
+genSshHost host user = maybe "" (\v -> T.unpack v ++ "@") user ++ T.unpack host
+
+{- Generates a ssh or rsync url from a SshData. -}
+genSshUrl :: SshData -> String
+genSshUrl sshdata = addtrailingslash $ T.unpack $ T.concat $
+	if (onlyCapability sshdata RsyncCapable)
+		then [u, h, T.pack ":", sshDirectory sshdata]
+		else [T.pack "ssh://", u, h, d]
+  where
+	u = maybe (T.pack "") (\v -> T.concat [v, T.pack "@"]) $ sshUserName sshdata
+	h = sshHostName sshdata
+	d
+		| T.pack "/" `T.isPrefixOf` sshDirectory sshdata = sshDirectory sshdata
+		| T.pack "~/" `T.isPrefixOf` sshDirectory sshdata = T.concat [T.pack "/", sshDirectory sshdata]
+		| otherwise = T.concat [T.pack "/~/", sshDirectory sshdata]
+	addtrailingslash s
+		| "/" `isSuffixOf` s = s
+		| otherwise = s ++ "/"
+
+{- Reverses genSshUrl -}
+parseSshUrl :: String -> Maybe SshData
+parseSshUrl u
+	| "ssh://" `isPrefixOf` u = fromssh (drop (length "ssh://") u)
+	| otherwise = fromrsync u
+  where
+	mkdata (userhost, dir) = Just $ SshData
+		{ sshHostName = T.pack host
+		, sshUserName = if null user then Nothing else Just $ T.pack user
+		, sshDirectory = T.pack dir
+		, sshRepoName = genSshRepoName host dir
+		-- dummy values, cannot determine from url
+		, sshPort = 22
+		, needsPubKey = True
+		, sshCapabilities = []
+		}
+	  where
+		(user, host) = if '@' `elem` userhost
+			then separate (== '@') userhost
+			else ("", userhost)
+	fromrsync s
+		| not (rsyncUrlIsShell u) = Nothing
+		| otherwise = mkdata $ separate (== ':') s
+	fromssh = mkdata . break (== '/')
+
+{- Generates a git remote name, like host_dir or host -}
+genSshRepoName :: String -> FilePath -> String
+genSshRepoName host dir
+	| null dir = makeLegalName host
+	| otherwise = makeLegalName $ host ++ "_" ++ dir
+
+{- The output of ssh, including both stdout and stderr. -}
+sshTranscript :: [String] -> (Maybe String) -> IO (String, Bool)
+sshTranscript opts input = processTranscript "ssh" opts input
+
+{- Ensure that the ssh public key doesn't include any ssh options, like
+ - command=foo, or other weirdness.
+ -
+ - The returned version of the key has its comment removed.
+ -}
+validateSshPubKey :: SshPubKey -> Either String SshPubKey
+validateSshPubKey pubkey
+	| length (lines pubkey) == 1 = check $ words pubkey
+	| otherwise = Left "too many lines in ssh public key"
+  where
+	check (prefix:key:_) = checkprefix prefix (unwords [prefix, key])
+	check _ = err "wrong number of words in ssh public key"
+
+	err msg = Left $ unwords [msg, pubkey]
+
+	checkprefix prefix validpubkey
+		| ssh == "ssh" && all isAlphaNum keytype = Right validpubkey
+		| otherwise = err "bad ssh public key prefix"
+	  where
+		(ssh, keytype) = separate (== '-') prefix
+
+addAuthorizedKeys :: Bool -> FilePath -> SshPubKey -> IO Bool
+addAuthorizedKeys gitannexshellonly dir pubkey = boolSystem "sh"
+	[ Param "-c" , Param $ addAuthorizedKeysCommand gitannexshellonly dir pubkey ]
+
+{- Should only be used within the same process that added the line;
+ - the layout of the line is not kepy stable across versions. -}
+removeAuthorizedKeys :: Bool -> FilePath -> SshPubKey -> IO ()
+removeAuthorizedKeys gitannexshellonly dir pubkey = do
+	let keyline = authorizedKeysLine gitannexshellonly dir pubkey
+	sshdir <- sshDir
+	let keyfile = sshdir </> "authorized_keys"
+	ls <- lines <$> readFileStrict keyfile
+	viaTmp writeSshConfig keyfile $ unlines $ filter (/= keyline) ls
+
+{- Implemented as a shell command, so it can be run on remote servers over
+ - ssh.
+ -
+ - The ~/.ssh/git-annex-shell wrapper script is created if not already
+ - present.
+ -}
+addAuthorizedKeysCommand :: Bool -> FilePath -> SshPubKey -> String
+addAuthorizedKeysCommand gitannexshellonly dir pubkey = intercalate "&&"
+	[ "mkdir -p ~/.ssh"
+	, intercalate "; "
+		[ "if [ ! -e " ++ wrapper ++ " ]"
+		, "then (" ++ intercalate ";" (map echoval script) ++ ") > " ++ wrapper
+		, "fi"
+		]
+	, "chmod 700 " ++ wrapper
+	, "touch ~/.ssh/authorized_keys"
+	, "chmod 600 ~/.ssh/authorized_keys"
+	, unwords
+		[ "echo"
+		, shellEscape $ authorizedKeysLine gitannexshellonly dir pubkey
+		, ">>~/.ssh/authorized_keys"
+		]
+	]
+  where
+	echoval v = "echo " ++ shellEscape v
+	wrapper = "~/.ssh/git-annex-shell"
+	script =
+		[ shebang_portable
+		, "set -e"
+		, "if [ \"x$SSH_ORIGINAL_COMMAND\" != \"x\" ]; then"
+		,   runshell "$SSH_ORIGINAL_COMMAND"
+		, "else"
+		,   runshell "$@"
+		, "fi"
+		]
+	runshell var = "exec git-annex-shell -c \"" ++ var ++ "\""
+
+authorizedKeysLine :: Bool -> FilePath -> SshPubKey -> String
+authorizedKeysLine gitannexshellonly dir pubkey
+	| gitannexshellonly = limitcommand ++ pubkey
+	{- TODO: Locking down rsync is difficult, requiring a rather
+	 - long perl script. -}
+	| otherwise = pubkey
+  where
+	limitcommand = "command=\"env GIT_ANNEX_SHELL_DIRECTORY="++shellEscape dir++" ~/.ssh/git-annex-shell\",no-agent-forwarding,no-port-forwarding,no-X11-forwarding,no-pty "
+
+{- Generates a ssh key pair. -}
+genSshKeyPair :: IO SshKeyPair
+genSshKeyPair = withTmpDir "git-annex-keygen" $ \dir -> do
+	ok <- boolSystem "ssh-keygen"
+		[ Param "-P", Param "" -- no password
+		, Param "-f", File $ dir </> "key"
+		]
+	unless ok $
+		error "ssh-keygen failed"
+	SshKeyPair
+		<$> readFile (dir </> "key.pub")
+		<*> readFile (dir </> "key")
+
+{- Installs a ssh key pair, and sets up ssh config with a mangled hostname
+ - that will enable use of the key. This way we avoid changing the user's
+ - regular ssh experience at all. Returns a modified SshData containing the
+ - mangled hostname.
+ -
+ - Note that the key files are put in ~/.ssh/git-annex/, rather than directly
+ - in ssh because of an **INSANE** behavior of gnome-keyring: It loads
+ - ~/.ssh/ANYTHING.pub, and uses them indiscriminately. But using this key
+ - for a normal login to the server will force git-annex-shell to run,
+ - and locks the user out. Luckily, it does not recurse into subdirectories.
+ -
+ - Similarly, IdentitiesOnly is set in the ssh config to prevent the
+ - ssh-agent from forcing use of a different key.
+ -
+ - Force strict host key checking to avoid repeated prompts
+ - when git-annex and git try to access the remote, if its
+ - host key has changed.
+ -}
+setupSshKeyPair :: SshKeyPair -> SshData -> IO SshData
+setupSshKeyPair sshkeypair sshdata = do
+	sshdir <- sshDir
+	createDirectoryIfMissing True $ parentDir $ sshdir </> sshprivkeyfile
+
+	unlessM (doesFileExist $ sshdir </> sshprivkeyfile) $
+		writeFileProtected (sshdir </> sshprivkeyfile) (sshPrivKey sshkeypair)
+	unlessM (doesFileExist $ sshdir </> sshpubkeyfile) $
+		writeFile (sshdir </> sshpubkeyfile) (sshPubKey sshkeypair)
+
+	setSshConfig sshdata
+		[ ("IdentityFile", "~/.ssh/" ++ sshprivkeyfile)
+		, ("IdentitiesOnly", "yes")
+		, ("StrictHostKeyChecking", "yes")
+		]
+  where
+	sshprivkeyfile = "git-annex" </> "key." ++ mangleSshHostName sshdata
+	sshpubkeyfile = sshprivkeyfile ++ ".pub"
+
+{- Fixes git-annex ssh key pairs configured in .ssh/config 
+ - by old versions to set IdentitiesOnly.
+ -
+ - Strategy: Search for IdentityFile lines with key.git-annex
+ - in their names. These are for git-annex ssh key pairs.
+ - Add the IdentitiesOnly line immediately after them, if not already
+ - present.
+ -}
+fixSshKeyPairIdentitiesOnly :: IO ()
+fixSshKeyPairIdentitiesOnly = changeUserSshConfig $ unlines . go [] . lines
+  where
+	go c [] = reverse c
+	go c (l:[])
+		| all (`isInfixOf` l) indicators = go (fixedline l:l:c) []
+		| otherwise = go (l:c) []
+	go c (l:next:rest)
+		| all (`isInfixOf` l) indicators && not ("IdentitiesOnly" `isInfixOf` next) = 
+			go (fixedline l:l:c) (next:rest)
+		| otherwise = go (l:c) (next:rest)
+	indicators = ["IdentityFile", "key.git-annex"]
+	fixedline tmpl = takeWhile isSpace tmpl ++ "IdentitiesOnly yes"
+
+{- Add StrictHostKeyChecking to any ssh config stanzas that were written
+ - by git-annex. -}
+fixUpSshRemotes :: IO ()
+fixUpSshRemotes = modifyUserSshConfig (map go)
+  where
+	go c@(HostConfig h _)
+		| "git-annex-" `isPrefixOf` h = fixupconfig c
+		| otherwise = c
+	go other = other
+
+	fixupconfig c = case findHostConfigKey c "StrictHostKeyChecking" of
+		Nothing -> addToHostConfig c "StrictHostKeyChecking" "yes"
+		Just _ -> c
+
+{- Setups up a ssh config with a mangled hostname.
+ - Returns a modified SshData containing the mangled hostname. -}
+setSshConfig :: SshData -> [(String, String)] -> IO SshData
+setSshConfig sshdata config = do
+	sshdir <- sshDir
+	createDirectoryIfMissing True sshdir
+	let configfile = sshdir </> "config"
+	unlessM (catchBoolIO $ isInfixOf mangledhost <$> readFile configfile) $ do
+		appendFile configfile $ unlines $
+			[ ""
+			, "# Added automatically by git-annex"
+			, "Host " ++ mangledhost
+			] ++ map (\(k, v) -> "\t" ++ k ++ " " ++ v)
+				(settings ++ config)
+		setSshConfigMode configfile
+
+	return $ sshdata { sshHostName = T.pack mangledhost }
+  where
+	mangledhost = mangleSshHostName sshdata
+	settings =
+		[ ("Hostname", T.unpack $ sshHostName sshdata)
+		, ("Port", show $ sshPort sshdata)
+		]
+
+{- This hostname is specific to a given repository on the ssh host,
+ - so it is based on the real hostname, the username, and the directory.
+ -
+ - The mangled hostname has the form "git-annex-realhostname-username-port_dir".
+ - The only use of "-" is to separate the parts shown; this is necessary
+ - to allow unMangleSshHostName to work. Any unusual characters in the
+ - username or directory are url encoded, except using "." rather than "%"
+ - (the latter has special meaning to ssh).
+ -}
+mangleSshHostName :: SshData -> String
+mangleSshHostName sshdata = "git-annex-" ++ T.unpack (sshHostName sshdata)
+	++ "-" ++ escape extra
+  where
+	extra = intercalate "_" $ map T.unpack $ catMaybes
+		[ sshUserName sshdata
+		, Just $ T.pack $ show $ sshPort sshdata
+		, Just $ sshDirectory sshdata
+		]
+	safe c
+		| isAlphaNum c = True
+		| c == '_' = True
+		| otherwise = False
+	escape s = replace "%" "." $ escapeURIString safe s
+
+{- Extracts the real hostname from a mangled ssh hostname. -}
+unMangleSshHostName :: String -> String
+unMangleSshHostName h = case split "-" h of
+	("git":"annex":rest) -> intercalate "-" (beginning rest)
+	_ -> h
+
+{- Does ssh have known_hosts data for a hostname? -}
+knownHost :: Text -> IO Bool
+knownHost hostname = do
+	sshdir <- sshDir
+	ifM (doesFileExist $ sshdir </> "known_hosts")
+		( not . null <$> checkhost
+		, return False
+		)
+  where
+	{- ssh-keygen -F can crash on some old known_hosts file -}
+	checkhost = catchDefaultIO "" $
+		readProcess "ssh-keygen" ["-F", T.unpack hostname]

Assistant/Sync.hs

@@ -0,0 +1,278 @@
+{- git-annex assistant repo syncing
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.Sync where
+
+import Assistant.Common
+import Assistant.Pushes
+import Assistant.NetMessager
+import Assistant.Types.NetMessager
+import Assistant.Alert
+import Assistant.Alert.Utility
+import Assistant.DaemonStatus
+import Assistant.ScanRemotes
+import Assistant.RemoteControl
+import qualified Command.Sync
+import Utility.Parallel
+import qualified Git
+import qualified Git.Branch
+import qualified Git.Command
+import qualified Git.Ref
+import qualified Remote
+import qualified Types.Remote as Remote
+import qualified Remote.List as Remote
+import qualified Annex.Branch
+import Annex.UUID
+import Annex.TaggedPush
+import qualified Config
+import Git.Config
+import Assistant.NamedThread
+import Assistant.Threads.Watcher (watchThread, WatcherControl(..))
+import Assistant.TransferSlots
+import Assistant.TransferQueue
+import Assistant.RepoProblem
+import Logs.Transfer
+
+import Data.Time.Clock
+import qualified Data.Map as M
+import qualified Data.Set as S
+import Control.Concurrent
+
+{- Syncs with remotes that may have been disconnected for a while.
+ - 
+ - First gets git in sync, and then prepares any necessary file transfers.
+ -
+ - An expensive full scan is queued when the git-annex branches of some of
+ - the remotes have diverged from the local git-annex branch. Otherwise,
+ - it's sufficient to requeue failed transfers.
+ -
+ - XMPP remotes are also signaled that we can push to them, and we request
+ - they push to us. Since XMPP pushes run ansynchronously, any scan of the
+ - XMPP remotes has to be deferred until they're done pushing to us, so
+ - all XMPP remotes are marked as possibly desynced.
+ -
+ - Also handles signaling any connectRemoteNotifiers, after the syncing is
+ - done.
+ -}
+reconnectRemotes :: Bool -> [Remote] -> Assistant ()
+reconnectRemotes _ [] = noop
+reconnectRemotes notifypushes rs = void $ do
+	rs' <- liftIO $ filterM (Remote.checkAvailable True) rs
+	unless (null rs') $ do
+		modifyDaemonStatus_ $ \s -> s
+			{ desynced = S.union (S.fromList $ map Remote.uuid xmppremotes) (desynced s) }
+		failedrs <- syncAction rs' (const go)
+		forM_ failedrs $ \r ->
+			whenM (liftIO $ Remote.checkAvailable False r) $
+				repoHasProblem (Remote.uuid r) (syncRemote r)
+		mapM_ signal $ filter (`notElem` failedrs) rs'
+  where
+	gitremotes = filter (notspecialremote . Remote.repo) rs
+	(xmppremotes, nonxmppremotes) = partition Remote.isXMPPRemote rs
+	notspecialremote r
+		| Git.repoIsUrl r = True
+		| Git.repoIsLocal r = True
+		| Git.repoIsLocalUnknown r = True
+		| otherwise = False
+	sync (Just branch) = do
+		(failedpull, diverged) <- manualPull (Just branch) gitremotes
+		now <- liftIO getCurrentTime
+		failedpush <- pushToRemotes' now notifypushes gitremotes
+		return (nub $ failedpull ++ failedpush, diverged)
+	{- No local branch exists yet, but we can try pulling. -}
+	sync Nothing = manualPull Nothing gitremotes
+	go = do
+		(failed, diverged) <- sync
+			=<< liftAnnex (inRepo Git.Branch.current)
+		addScanRemotes diverged $
+			filter (not . remoteAnnexIgnore . Remote.gitconfig)
+				nonxmppremotes
+		return failed
+	signal r = liftIO . mapM_ (flip tryPutMVar ())
+		=<< fromMaybe [] . M.lookup (Remote.uuid r) . connectRemoteNotifiers
+			<$> getDaemonStatus
+
+{- Pushes the local sync branch to all remotes, in
+ - parallel, along with the git-annex branch. This is the same
+ - as "git annex sync", except in parallel, and will co-exist with use of
+ - "git annex sync".
+ -
+ - After the pushes to normal git remotes, also signals XMPP clients that
+ - they can request an XMPP push.
+ -
+ - Avoids running possibly long-duration commands in the Annex monad, so
+ - as not to block other threads.
+ -
+ - This can fail, when the remote's sync branch (or git-annex branch) has
+ - been updated by some other remote pushing into it, or by the remote
+ - itself. To handle failure, a manual pull and merge is done, and the push
+ - is retried.
+ -
+ - When there's a lot of activity, we may fail more than once.
+ - On the other hand, we may fail because the remote is not available.
+ - Rather than retrying indefinitely, after the first retry we enter a
+ - fallback mode, where our push is guarenteed to succeed if the remote is
+ - reachable. If the fallback fails, the push is queued to be retried
+ - later.
+ -
+ - Returns any remotes that it failed to push to.
+ -}
+pushToRemotes :: Bool -> [Remote] -> Assistant [Remote]
+pushToRemotes notifypushes remotes = do
+	now <- liftIO getCurrentTime
+	let remotes' = filter (not . remoteAnnexReadOnly . Remote.gitconfig) remotes
+	syncAction remotes' (pushToRemotes' now notifypushes)
+pushToRemotes' :: UTCTime -> Bool -> [Remote] -> Assistant [Remote]
+pushToRemotes' now notifypushes remotes = do
+	(g, branch, u) <- liftAnnex $ do
+		Annex.Branch.commit "update"
+		(,,)
+			<$> gitRepo
+			<*> inRepo Git.Branch.current
+			<*> getUUID
+	let (xmppremotes, normalremotes) = partition Remote.isXMPPRemote remotes
+	ret <- go True branch g u normalremotes
+	unless (null xmppremotes) $ do
+		shas <- liftAnnex $ map fst <$>
+			inRepo (Git.Ref.matchingWithHEAD
+				[Annex.Branch.fullname, Git.Ref.headRef])
+		forM_ xmppremotes $ \r -> sendNetMessage $
+			Pushing (getXMPPClientID r) (CanPush u shas)
+	return ret
+  where
+	go _ Nothing _ _ _ = return [] -- no branch, so nothing to do
+	go _ _ _ _ [] = return [] -- no remotes, so nothing to do
+	go shouldretry (Just branch) g u rs =  do
+		debug ["pushing to", show rs]
+		(succeeded, failed) <- liftIO $ inParallel (push g branch) rs
+		updatemap succeeded []
+		if null failed
+			then do
+				when notifypushes $
+					sendNetMessage $ NotifyPush $
+						map Remote.uuid succeeded
+				return failed
+			else if shouldretry
+				then retry branch g u failed
+				else fallback branch g u failed
+
+	updatemap succeeded failed = changeFailedPushMap $ \m ->
+		M.union (makemap failed) $
+			M.difference m (makemap succeeded)
+	makemap l = M.fromList $ zip l (repeat now)
+
+	retry branch g u rs = do
+		debug ["trying manual pull to resolve failed pushes"]
+		void $ manualPull (Just branch) rs
+		go False (Just branch) g u rs
+
+	fallback branch g u rs = do
+		debug ["fallback pushing to", show rs]
+		(succeeded, failed) <- liftIO $
+			inParallel (\r -> taggedPush u Nothing branch r g) rs
+		updatemap succeeded failed
+		when (notifypushes && (not $ null succeeded)) $
+			sendNetMessage $ NotifyPush $
+				map Remote.uuid succeeded
+		return failed
+		
+	push g branch remote = Command.Sync.pushBranch remote branch g
+
+{- Displays an alert while running an action that syncs with some remotes,
+ - and returns any remotes that it failed to sync with.
+ -
+ - XMPP remotes are handled specially; since the action can only start
+ - an async process for them, they are not included in the alert, but are
+ - still passed to the action.
+ -
+ - Readonly remotes are also hidden (to hide the web special remote).
+ -}
+syncAction :: [Remote] -> ([Remote] -> Assistant [Remote]) -> Assistant [Remote]
+syncAction rs a
+	| null visibleremotes = a rs
+	| otherwise = do
+		i <- addAlert $ syncAlert visibleremotes
+		failed <- a rs
+		let failed' = filter (not . Git.repoIsLocalUnknown . Remote.repo) failed
+		let succeeded = filter (`notElem` failed) visibleremotes
+		if null succeeded && null failed'
+			then removeAlert i
+			else updateAlertMap $ mergeAlert i $
+				syncResultAlert succeeded failed'
+		return failed
+  where
+	visibleremotes = filter (not . Remote.readonly) $
+		filter (not . Remote.isXMPPRemote) rs
+
+{- Manually pull from remotes and merge their branches. Returns any
+ - remotes that it failed to pull from, and a Bool indicating
+ - whether the git-annex branches of the remotes and local had
+ - diverged before the pull.
+ -
+ - After pulling from the normal git remotes, requests pushes from any
+ - XMPP remotes. However, those pushes will run asynchronously, so their
+ - results are not included in the return data.
+ -}
+manualPull :: Maybe Git.Ref -> [Remote] -> Assistant ([Remote], Bool)
+manualPull currentbranch remotes = do
+	g <- liftAnnex gitRepo
+	let (xmppremotes, normalremotes) = partition Remote.isXMPPRemote remotes
+	failed <- liftIO $ forM normalremotes $ \r ->
+		ifM (Git.Command.runBool [Param "fetch", Param $ Remote.name r] g)
+			( return Nothing
+			, return $ Just r
+			)
+	haddiverged <- liftAnnex Annex.Branch.forceUpdate
+	forM_ normalremotes $ \r ->
+		liftAnnex $ Command.Sync.mergeRemote r currentbranch
+	u <- liftAnnex getUUID
+	forM_ xmppremotes $ \r ->
+		sendNetMessage $ Pushing (getXMPPClientID r) (PushRequest u)
+	return (catMaybes failed, haddiverged)
+
+{- Start syncing a remote, using a background thread. -}
+syncRemote :: Remote -> Assistant ()
+syncRemote remote = do
+	updateSyncRemotes
+	thread <- asIO $ do
+		reconnectRemotes False [remote]
+		addScanRemotes True [remote]
+	void $ liftIO $ forkIO $ thread
+
+{- Use Nothing to change autocommit setting; or a remote to change
+ - its sync setting. -}
+changeSyncable :: Maybe Remote -> Bool -> Assistant ()
+changeSyncable Nothing enable = do
+	liftAnnex $ Config.setConfig key (boolConfig enable)
+	liftIO . maybe noop (`throwTo` signal)
+		=<< namedThreadId watchThread
+  where
+	key = Config.annexConfig "autocommit"
+	signal
+		| enable = ResumeWatcher
+		| otherwise = PauseWatcher
+changeSyncable (Just r) True = do
+	liftAnnex $ changeSyncFlag r True
+	syncRemote r
+	sendRemoteControl RELOAD
+changeSyncable (Just r) False = do
+	liftAnnex $ changeSyncFlag r False
+	updateSyncRemotes
+	{- Stop all transfers to or from this remote.
+	 - XXX Can't stop any ongoing scan, or git syncs. -}
+	void $ dequeueTransfers tofrom
+	mapM_ (cancelTransfer False) =<<
+		filter tofrom . M.keys . currentTransfers <$> getDaemonStatus
+  where
+	tofrom t = transferUUID t == Remote.uuid r
+
+changeSyncFlag :: Remote -> Bool -> Annex ()
+changeSyncFlag r enabled = do
+	Config.setConfig key (boolConfig enabled)
+	void Remote.remoteListRefresh
+  where
+	key = Config.remoteConfig (Remote.repo r) "sync"

Assistant/Threads/Committer.hs

@@ -0,0 +1,479 @@
+{- git-annex assistant commit thread
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Assistant.Threads.Committer where
+
+import Assistant.Common
+import Assistant.Changes
+import Assistant.Types.Changes
+import Assistant.Commits
+import Assistant.Alert
+import Assistant.DaemonStatus
+import Assistant.TransferQueue
+import Assistant.Drop
+import Logs.Transfer
+import Logs.Location
+import qualified Annex.Queue
+import qualified Git.LsFiles
+import qualified Command.Add
+import Utility.ThreadScheduler
+import qualified Utility.Lsof as Lsof
+import qualified Utility.DirWatcher as DirWatcher
+import Types.KeySource
+import Config
+import Annex.Content
+import Annex.Link
+import Annex.CatFile
+import qualified Annex
+import Utility.InodeCache
+import Annex.Content.Direct
+import qualified Command.Sync
+import qualified Git.Branch
+
+import Data.Time.Clock
+import Data.Tuple.Utils
+import qualified Data.Set as S
+import qualified Data.Map as M
+import Data.Either
+import Control.Concurrent
+
+{- This thread makes git commits at appropriate times. -}
+commitThread :: NamedThread
+commitThread = namedThread "Committer" $ do
+	havelsof <- liftIO $ inPath "lsof"
+	delayadd <- liftAnnex $
+		maybe delayaddDefault (return . Just . Seconds)
+			=<< annexDelayAdd <$> Annex.getGitConfig
+	msg <- liftAnnex Command.Sync.commitMsg
+	waitChangeTime $ \(changes, time) -> do
+		readychanges <- handleAdds havelsof delayadd changes
+		if shouldCommit False time (length readychanges) readychanges
+			then do
+				debug
+					[ "committing"
+					, show (length readychanges)
+					, "changes"
+					]
+				void $ alertWhile commitAlert $
+					liftAnnex $ commitStaged msg
+				recordCommit
+				let numchanges = length readychanges
+				mapM_ checkChangeContent readychanges
+				return numchanges
+			else do
+				refill readychanges
+				return 0
+
+refill :: [Change] -> Assistant ()	
+refill [] = noop
+refill cs = do
+	debug ["delaying commit of", show (length cs), "changes"]
+	refillChanges cs
+
+{- Wait for one or more changes to arrive to be committed, and then
+ - runs an action to commit them. If more changes arrive while this is
+ - going on, they're handled intelligently, batching up changes into
+ - large commits where possible, doing rename detection, and
+ - commiting immediately otherwise. -}
+waitChangeTime :: (([Change], UTCTime) -> Assistant Int) -> Assistant ()
+waitChangeTime a = waitchanges 0
+  where
+	waitchanges lastcommitsize = do
+		-- Wait one one second as a simple rate limiter.
+		liftIO $ threadDelaySeconds (Seconds 1)
+		-- Now, wait until at least one change is available for
+		-- processing.
+		cs <- getChanges
+		handlechanges cs lastcommitsize
+	handlechanges changes lastcommitsize = do
+		let len = length changes
+		-- See if now's a good time to commit.
+		now <- liftIO getCurrentTime
+		scanning <- not . scanComplete <$> getDaemonStatus
+		case (lastcommitsize >= maxCommitSize, shouldCommit scanning now len changes, possiblyrename changes) of
+			(True, True, _)
+				| len > maxCommitSize -> 
+					a (changes, now) >>= waitchanges
+				| otherwise -> aftermaxcommit changes
+			(_, True, False) ->
+				a (changes, now) >>= waitchanges
+			(_, True, True) -> do
+				morechanges <- getrelatedchanges changes
+				a (changes ++ morechanges, now) >>= waitchanges
+			_ -> do
+				refill changes
+				waitchanges lastcommitsize
+	
+	{- Did we perhaps only get one of the AddChange and RmChange pair
+	 - that make up a file rename? Or some of the pairs that make up 
+	 - a directory rename?
+	 -}
+	possiblyrename = all renamepart
+
+	renamepart (PendingAddChange _ _) = True
+	renamepart c = isRmChange c
+
+	{- Gets changes related to the passed changes, without blocking
+	 - very long.
+	 -
+	 - If there are multiple RmChanges, this is probably a directory
+	 - rename, in which case it may be necessary to wait longer to get
+	 - all the Changes involved.
+	 -}
+	getrelatedchanges oldchanges
+		| length (filter isRmChange oldchanges) > 1 =
+			concat <$> getbatchchanges []
+		| otherwise = do
+			liftIO humanImperceptibleDelay
+			getAnyChanges
+	getbatchchanges cs = do
+		liftIO $ threadDelay $ fromIntegral $ oneSecond `div` 10
+		cs' <- getAnyChanges
+		if null cs'
+			then return cs
+			else getbatchchanges (cs':cs)
+
+	{- The last commit was maximum size, so it's very likely there
+	 - are more changes and we'd like to ensure we make another commit
+	 - of maximum size if possible.
+	 -
+	 - But, it can take a while for the Watcher to wake back up
+	 - after a commit. It can get blocked by another thread
+	 - that is using the Annex state, such as a git-annex branch
+	 - commit. Especially after such a large commit, this can
+	 - take several seconds. When this happens, it defeats the
+	 - normal commit batching, which sees some old changes the
+	 - Watcher found while the commit was being prepared, and sees
+	 - no recent ones, and wants to commit immediately.
+	 -
+	 - All that we need to do, then, is wait for the Watcher to
+	 - wake up, and queue up one more change.
+	 -
+	 - However, it's also possible that we're at the end of changes for
+	 - now. So to avoid waiting a really long time before committing
+	 - those changes we have, poll for up to 30 seconds, and then
+	 - commit them.
+	 -
+	 - Also, try to run something in Annex, to ensure we block
+	 - longer if the Annex state is indeed blocked.
+	 -}
+	aftermaxcommit oldchanges = loop (30 :: Int)
+	  where
+		loop 0 = continue oldchanges
+		loop n = do
+			liftAnnex noop -- ensure Annex state is free
+			liftIO $ threadDelaySeconds (Seconds 1)
+			changes <- getAnyChanges
+			if null changes
+				then loop (n - 1)
+				else continue (oldchanges ++ changes)
+		continue cs
+			| null cs = waitchanges 0
+			| otherwise = handlechanges cs 0
+
+isRmChange :: Change -> Bool
+isRmChange (Change { changeInfo = i }) | i == RmChange = True
+isRmChange _ = False
+
+{- An amount of time that is hopefully imperceptably short for humans,
+ - while long enough for a computer to get some work done. 
+ - Note that 0.001 is a little too short for rename change batching to
+ - work. -}
+humanImperceptibleInterval :: NominalDiffTime
+humanImperceptibleInterval = 0.01
+
+humanImperceptibleDelay :: IO ()
+humanImperceptibleDelay = threadDelay $
+	truncate $ humanImperceptibleInterval * fromIntegral oneSecond
+
+maxCommitSize :: Int
+maxCommitSize = 5000
+
+{- Decide if now is a good time to make a commit.
+ - Note that the list of changes has an undefined order.
+ -
+ - Current strategy: If there have been 10 changes within the past second,
+ - a batch activity is taking place, so wait for later.
+ -}
+shouldCommit :: Bool -> UTCTime -> Int -> [Change] -> Bool
+shouldCommit scanning now len changes
+	| scanning = len >= maxCommitSize
+	| len == 0 = False
+	| len >= maxCommitSize = True
+	| length recentchanges < 10 = True
+	| otherwise = False -- batch activity
+  where
+	thissecond c = timeDelta c <= 1
+	recentchanges = filter thissecond changes
+	timeDelta c = now `diffUTCTime` changeTime c
+
+commitStaged :: String -> Annex Bool
+commitStaged msg = do
+	{- This could fail if there's another commit being made by
+	 - something else. -}
+	v <- tryNonAsync Annex.Queue.flush
+	case v of
+		Left _ -> return False
+		Right _ -> do
+			ok <- Command.Sync.commitStaged Git.Branch.AutomaticCommit msg
+			when ok $
+				Command.Sync.updateSyncBranch =<< inRepo Git.Branch.current
+			return ok
+
+{- OSX needs a short delay after a file is added before locking it down,
+ - when using a non-direct mode repository, as pasting a file seems to
+ - try to set file permissions or otherwise access the file after closing
+ - it. -}
+delayaddDefault :: Annex (Maybe Seconds)
+#ifdef darwin_HOST_OS
+delayaddDefault = ifM isDirect
+	( return Nothing
+	, return $ Just $ Seconds 1
+	)
+#else
+delayaddDefault = return Nothing
+#endif
+
+{- If there are PendingAddChanges, or InProcessAddChanges, the files
+ - have not yet actually been added to the annex, and that has to be done
+ - now, before committing.
+ -
+ - Deferring the adds to this point causes batches to be bundled together,
+ - which allows faster checking with lsof that the files are not still open
+ - for write by some other process, and faster checking with git-ls-files
+ - that the files are not already checked into git.
+ -
+ - When a file is added, Inotify will notice the new symlink. So this waits
+ - for additional Changes to arrive, so that the symlink has hopefully been
+ - staged before returning, and will be committed immediately.
+ -
+ - OTOH, for kqueue, eventsCoalesce, so instead the symlink is directly
+ - created and staged.
+ -
+ - Returns a list of all changes that are ready to be committed.
+ - Any pending adds that are not ready yet are put back into the ChangeChan,
+ - where they will be retried later.
+ -}
+handleAdds :: Bool -> Maybe Seconds -> [Change] -> Assistant [Change]
+handleAdds havelsof delayadd cs = returnWhen (null incomplete) $ do
+	let (pending, inprocess) = partition isPendingAddChange incomplete
+	direct <- liftAnnex isDirect
+	(pending', cleanup) <- if direct
+		then return (pending, noop)
+		else findnew pending
+	(postponed, toadd) <- partitionEithers <$> safeToAdd havelsof delayadd pending' inprocess
+	cleanup
+
+	unless (null postponed) $
+		refillChanges postponed
+
+	returnWhen (null toadd) $ do
+		added <- addaction toadd $
+			catMaybes <$> if direct
+				then adddirect toadd
+				else forM toadd add
+		if DirWatcher.eventsCoalesce || null added || direct
+			then return $ added ++ otherchanges
+			else do
+				r <- handleAdds havelsof delayadd =<< getChanges
+				return $ r ++ added ++ otherchanges
+  where
+	(incomplete, otherchanges) = partition (\c -> isPendingAddChange c || isInProcessAddChange c) cs
+		
+	findnew [] = return ([], noop)
+	findnew pending@(exemplar:_) = do
+		(newfiles, cleanup) <- liftAnnex $
+			inRepo (Git.LsFiles.notInRepo False $ map changeFile pending)
+		-- note: timestamp info is lost here
+		let ts = changeTime exemplar
+		return (map (PendingAddChange ts) newfiles, void $ liftIO cleanup)
+
+	returnWhen c a
+		| c = return otherchanges
+		| otherwise = a
+
+	add :: Change -> Assistant (Maybe Change)
+	add change@(InProcessAddChange { keySource = ks }) = 
+		catchDefaultIO Nothing <~> doadd
+	  where
+		doadd = sanitycheck ks $ do
+			(mkey, mcache) <- liftAnnex $ do
+				showStart "add" $ keyFilename ks
+				Command.Add.ingest $ Just ks
+			maybe (failedingest change) (done change mcache $ keyFilename ks) mkey
+	add _ = return Nothing
+
+	{- In direct mode, avoid overhead of re-injesting a renamed
+	 - file, by examining the other Changes to see if a removed
+	 - file has the same InodeCache as the new file. If so,
+	 - we can just update bookkeeping, and stage the file in git.
+	 -}
+	adddirect :: [Change] -> Assistant [Maybe Change]
+	adddirect toadd = do
+		ct <- liftAnnex compareInodeCachesWith
+		m <- liftAnnex $ removedKeysMap ct cs
+		delta <- liftAnnex getTSDelta
+		if M.null m
+			then forM toadd add
+			else forM toadd $ \c -> do
+				mcache <- liftIO $ genInodeCache (changeFile c) delta
+				case mcache of
+					Nothing -> add c
+					Just cache ->
+						case M.lookup (inodeCacheToKey ct cache) m of
+							Nothing -> add c
+							Just k -> fastadd c k
+
+	fastadd :: Change -> Key -> Assistant (Maybe Change)
+	fastadd change key = do
+		let source = keySource change
+		liftAnnex $ Command.Add.finishIngestDirect key source
+		done change Nothing (keyFilename source) key
+
+	removedKeysMap :: InodeComparisonType -> [Change] -> Annex (M.Map InodeCacheKey Key)
+	removedKeysMap ct l = do
+		mks <- forM (filter isRmChange l) $ \c ->
+			catKeyFile $ changeFile c
+		M.fromList . concat <$> mapM mkpairs (catMaybes mks)
+	  where
+		mkpairs k = map (\c -> (inodeCacheToKey ct c, k)) <$>
+			recordedInodeCache k
+
+	failedingest change = do
+		refill [retryChange change]
+		liftAnnex showEndFail
+		return Nothing
+
+	done change mcache file key = liftAnnex $ do
+		logStatus key InfoPresent
+		link <- ifM isDirect
+			( calcRepo $ gitAnnexLink file key
+			, Command.Add.link file key mcache
+			)
+		whenM (pure DirWatcher.eventsCoalesce <||> isDirect) $
+			stageSymlink file =<< hashSymlink link
+		showEndOk
+		return $ Just $ finishedChange change key
+
+	{- Check that the keysource's keyFilename still exists,
+	 - and is still a hard link to its contentLocation,
+	 - before ingesting it. -}
+	sanitycheck keysource a = do
+		fs <- liftIO $ getSymbolicLinkStatus $ keyFilename keysource
+		ks <- liftIO $ getSymbolicLinkStatus $ contentLocation keysource
+		if deviceID ks == deviceID fs && fileID ks == fileID fs
+			then a
+			else do
+				-- remove the hard link
+				when (contentLocation keysource /= keyFilename keysource) $
+					void $ liftIO $ tryIO $ removeFile $ contentLocation keysource
+				return Nothing
+
+	{- Shown an alert while performing an action to add a file or
+	 - files. When only a few files are added, their names are shown
+	 - in the alert. When it's a batch add, the number of files added
+	 - is shown.
+	 -
+	 - Add errors tend to be transient and will be
+	 - automatically dealt with, so the alert is always told
+	 - the add succeeded.
+	 -}
+	addaction [] a = a
+	addaction toadd a = alertWhile' (addFileAlert $ map changeFile toadd) $
+		(,) 
+			<$> pure True
+			<*> a
+
+{- Files can Either be Right to be added now,
+ - or are unsafe, and must be Left for later.
+ -
+ - Check by running lsof on the repository.
+ -}
+safeToAdd :: Bool -> Maybe Seconds -> [Change] -> [Change] -> Assistant [Either Change Change]
+safeToAdd _ _ [] [] = return []
+safeToAdd havelsof delayadd pending inprocess = do
+	maybe noop (liftIO . threadDelaySeconds) delayadd
+	liftAnnex $ do
+		keysources <- forM pending $ Command.Add.lockDown . changeFile
+		let inprocess' = inprocess ++ mapMaybe mkinprocess (zip pending keysources)
+		openfiles <- if havelsof
+			then S.fromList . map fst3 . filter openwrite <$>
+				findopenfiles (map keySource inprocess')
+			else pure S.empty
+		let checked = map (check openfiles) inprocess'
+
+		{- If new events are received when files are closed,
+		 - there's no need to retry any changes that cannot
+		 - be done now. -}
+		if DirWatcher.closingTracked
+			then do
+				mapM_ canceladd $ lefts checked
+				allRight $ rights checked
+			else return checked
+  where
+	check openfiles change@(InProcessAddChange { keySource = ks })
+		| S.member (contentLocation ks) openfiles = Left change
+	check _ change = Right change
+
+	mkinprocess (c, Just ks) = Just InProcessAddChange
+		{ changeTime = changeTime c
+		, keySource = ks
+		}
+	mkinprocess (_, Nothing) = Nothing
+
+	canceladd (InProcessAddChange { keySource = ks }) = do
+		warning $ keyFilename ks
+			++ " still has writers, not adding"
+		-- remove the hard link
+		when (contentLocation ks /= keyFilename ks) $
+			void $ liftIO $ tryIO $ removeFile $ contentLocation ks
+	canceladd _ = noop
+
+	openwrite (_file, mode, _pid)
+		| mode == Lsof.OpenWriteOnly = True
+		| mode == Lsof.OpenReadWrite = True
+		| mode == Lsof.OpenUnknown = True
+		| otherwise = False
+
+	allRight = return . map Right
+
+	{- Normally the KeySources are locked down inside the temp directory,
+	 - so can just lsof that, which is quite efficient.
+	 -
+	 - In crippled filesystem mode, there is no lock down, so must run lsof
+	 - on each individual file.
+	 -}
+	findopenfiles keysources = ifM crippledFileSystem
+		( liftIO $ do
+			let segments = segmentXargs $ map keyFilename keysources
+			concat <$> forM segments (\fs -> Lsof.query $ "--" : fs)
+		, do
+			tmpdir <- fromRepo gitAnnexTmpMiscDir
+			liftIO $ Lsof.queryDir tmpdir
+		)
+
+{- After a Change is committed, queue any necessary transfers or drops
+ - of the content of the key.
+ -
+ - This is not done during the startup scan, because the expensive
+ - transfer scan does the same thing then.
+ -}
+checkChangeContent :: Change -> Assistant ()
+checkChangeContent change@(Change { changeInfo = i }) =
+	case changeInfoKey i of
+		Nothing -> noop
+		Just k -> whenM (scanComplete <$> getDaemonStatus) $ do
+			present <- liftAnnex $ inAnnex k
+			void $ if present
+				then queueTransfers "new file created" Next k (Just f) Upload
+				else queueTransfers "new or renamed file wanted" Next k (Just f) Download
+			handleDrops "file renamed" present k (Just f) Nothing
+  where
+	f = changeFile change
+checkChangeContent _ = noop

Assistant/Threads/ConfigMonitor.hs

@@ -0,0 +1,91 @@
+{- git-annex assistant config monitor thread
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.Threads.ConfigMonitor where
+
+import Assistant.Common
+import Assistant.BranchChange
+import Assistant.DaemonStatus
+import Assistant.Commits
+import Utility.ThreadScheduler
+import Logs
+import Logs.UUID
+import Logs.Trust
+import Logs.PreferredContent
+import Logs.Group
+import Logs.NumCopies
+import Remote.List (remoteListRefresh)
+import qualified Git.LsTree as LsTree
+import Git.FilePath
+import qualified Annex.Branch
+
+import qualified Data.Set as S
+
+{- This thread detects when configuration changes have been made to the
+ - git-annex branch and reloads cached configuration.
+ -
+ - If the branch is frequently changing, it's checked for configuration
+ - changes no more often than once every 60 seconds. On the other hand,
+ - if the branch has not changed in a while, configuration changes will
+ - be detected immediately.
+ -}
+configMonitorThread :: NamedThread
+configMonitorThread = namedThread "ConfigMonitor" $ loop =<< getConfigs
+  where
+	loop old = do
+		waitBranchChange
+		new <- getConfigs
+		when (old /= new) $ do
+			let changedconfigs = new `S.difference` old
+			debug $ "reloading config" : 
+				map fst (S.toList changedconfigs)
+			reloadConfigs new
+			{- Record a commit to get this config
+			 - change pushed out to remotes. -}
+			recordCommit
+		liftIO $ threadDelaySeconds (Seconds 60)
+		loop new
+
+{- Config files, and their checksums. -}
+type Configs = S.Set (FilePath, String)
+
+{- All git-annex's config files, and actions to run when they change. -}
+configFilesActions :: [(FilePath, Assistant ())]
+configFilesActions =
+	[ (uuidLog, void $ liftAnnex uuidMapLoad)
+	, (remoteLog, void $ liftAnnex remoteListRefresh)
+	, (trustLog, void $ liftAnnex trustMapLoad)
+	, (groupLog, void $ liftAnnex groupMapLoad)
+	, (numcopiesLog, void $ liftAnnex globalNumCopiesLoad)
+	, (scheduleLog, void updateScheduleLog)
+	-- Preferred and required content settings depend on most of the
+	-- other configs, so will be reloaded whenever any configs change.
+	, (preferredContentLog, noop)
+	, (requiredContentLog, noop)
+	, (groupPreferredContentLog, noop)
+	]
+
+reloadConfigs :: Configs -> Assistant ()
+reloadConfigs changedconfigs = do
+	sequence_ as
+	void $ liftAnnex preferredRequiredMapsLoad
+	{- Changes to the remote log, or the trust log, can affect the
+	 - syncRemotes list. Changes to the uuid log may affect its
+	 - display so are also included. -}
+	when (any (`elem` fs) [remoteLog, trustLog, uuidLog])
+		updateSyncRemotes
+  where
+	(fs, as) = unzip $ filter (flip S.member changedfiles . fst)
+		configFilesActions
+	changedfiles = S.map fst changedconfigs
+
+getConfigs :: Assistant Configs
+getConfigs = S.fromList . map extract
+	<$> liftAnnex (inRepo $ LsTree.lsTreeFiles Annex.Branch.fullname files)
+  where
+	files = map fst configFilesActions
+	extract treeitem = (getTopFilePath $ LsTree.file treeitem, LsTree.sha treeitem)

Assistant/Threads/Cronner.hs

@@ -0,0 +1,225 @@
+{- git-annex assistant sceduled jobs runner
+ -
+ - Copyright 2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE DeriveDataTypeable #-}
+
+module Assistant.Threads.Cronner (
+	cronnerThread
+) where
+
+import Assistant.Common
+import Assistant.DaemonStatus
+import Utility.NotificationBroadcaster
+import Annex.UUID
+import Config.Files
+import Logs.Schedule
+import Utility.Scheduled
+import Types.ScheduledActivity
+import Utility.ThreadScheduler
+import Utility.HumanTime
+import Utility.Batch
+import Assistant.TransferQueue
+import Annex.Content
+import Logs.Transfer
+import Assistant.Types.UrlRenderer
+import Assistant.Alert
+import Remote
+import qualified Types.Remote as Remote
+import qualified Git
+import qualified Git.Fsck
+import Assistant.Fsck
+import Assistant.Repair
+
+import Control.Concurrent.Async
+import Control.Concurrent.MVar
+import Data.Time.LocalTime
+import Data.Time.Clock
+import qualified Data.Map as M
+import qualified Data.Set as S
+
+{- Loads schedules for this repository, and fires off one thread for each 
+ - scheduled event that runs on this repository. Each thread sleeps until
+ - its event is scheduled to run.
+ -
+ - To handle events that run on remotes, which need to only run when
+ - their remote gets connected, threads are also started, and are passed
+ - a MVar to wait on, which is stored in the DaemonStatus's
+ - connectRemoteNotifiers.
+ -
+ - In the meantime the main thread waits for any changes to the
+ - schedules. When there's a change, compare the old and new list of
+ - schedules to find deleted and added ones. Start new threads for added
+ - ones, and kill the threads for deleted ones. -}
+cronnerThread :: UrlRenderer -> NamedThread
+cronnerThread urlrenderer = namedThreadUnchecked "Cronner" $ do
+	fsckNudge urlrenderer Nothing
+	dstatus <- getDaemonStatus
+	h <- liftIO $ newNotificationHandle False (scheduleLogNotifier dstatus)
+	go h M.empty M.empty
+  where
+	go h amap nmap = do
+		activities <- liftAnnex $ scheduleGet =<< getUUID
+
+		let addedactivities = activities `S.difference` M.keysSet amap
+		let removedactivities = M.keysSet amap `S.difference` activities
+
+		forM_ (S.toList removedactivities) $ \activity ->
+			case M.lookup activity amap of
+				Just a -> do
+					debug ["stopping removed job for", fromScheduledActivity activity, show (asyncThreadId a)]
+					liftIO $ cancel a
+				Nothing -> noop
+
+		lastruntimes <- liftAnnex getLastRunTimes
+		started <- startactivities (S.toList addedactivities) lastruntimes
+		let addedamap = M.fromList $ map fst started
+		let addednmap = M.fromList $ catMaybes $ map snd started
+
+		let removefiltered = M.filterWithKey (\k _ -> S.member k removedactivities)
+		let amap' = M.difference (M.union addedamap amap) (removefiltered amap)
+		let nmap' = M.difference (M.union addednmap nmap) (removefiltered nmap)
+		modifyDaemonStatus_ $ \s -> s { connectRemoteNotifiers = M.fromListWith (++) (M.elems nmap') }
+
+		liftIO $ waitNotification h
+		debug ["reloading changed activities"]
+		go h amap' nmap'
+	startactivities as lastruntimes = forM as $ \activity ->
+		case connectActivityUUID activity of
+			Nothing -> do
+				runner <- asIO2 (sleepingActivityThread urlrenderer)
+				a <- liftIO $ async $
+					runner activity (M.lookup activity lastruntimes)
+				return ((activity, a), Nothing)
+			Just u -> do
+				mvar <- liftIO newEmptyMVar
+				runner <- asIO2 (remoteActivityThread urlrenderer mvar)
+				a <- liftIO $ async $
+					runner activity (M.lookup activity lastruntimes)
+				return ((activity, a), Just (activity, (u, [mvar])))
+
+{- Calculate the next time the activity is scheduled to run, then
+ - sleep until that time, and run it. Then call setLastRunTime, and
+ - loop.
+ -}
+sleepingActivityThread :: UrlRenderer -> ScheduledActivity -> Maybe LocalTime -> Assistant ()
+sleepingActivityThread urlrenderer activity lasttime = go lasttime =<< getnexttime lasttime
+  where
+	getnexttime = liftIO . nextTime schedule
+	go _ Nothing = debug ["no scheduled events left for", desc]
+	go l (Just (NextTimeExactly t)) = waitrun l t Nothing
+	go l (Just (NextTimeWindow windowstart windowend)) =
+		waitrun l windowstart (Just windowend)
+	desc = fromScheduledActivity activity
+	schedule = getSchedule activity
+	waitrun l t mmaxt = do
+		seconds <- liftIO $ secondsUntilLocalTime t
+		when (seconds > Seconds 0) $ do
+			debug ["waiting", show seconds, "for next scheduled", desc]
+			liftIO $ threadDelaySeconds seconds
+		now <- liftIO getCurrentTime
+		tz <- liftIO $ getTimeZone now
+		let nowt = utcToLocalTime tz now
+		if tolate nowt tz
+			then do
+				debug ["too late to run scheduled", desc]
+				go l =<< getnexttime l
+			else run nowt
+	  where
+		tolate nowt tz = case mmaxt of
+			Just maxt -> nowt > maxt
+			-- allow the job to start 10 minutes late
+			Nothing ->diffUTCTime 
+				(localTimeToUTC tz nowt)
+				(localTimeToUTC tz t) > 600
+	run nowt = do
+		runActivity urlrenderer activity nowt
+		go (Just nowt) =<< getnexttime (Just nowt)
+
+{- Wait for the remote to become available by waiting on the MVar.
+ - Then check if the time is within a time window when activity
+ - is scheduled to run, and if so run it.
+ - Otherwise, just wait again on the MVar.
+ -}
+remoteActivityThread :: UrlRenderer -> MVar () -> ScheduledActivity -> Maybe LocalTime -> Assistant ()
+remoteActivityThread urlrenderer mvar activity lasttime = do
+	liftIO $ takeMVar mvar
+	go =<< liftIO (nextTime (getSchedule activity) lasttime)
+  where
+	go (Just (NextTimeWindow windowstart windowend)) = do
+		now <- liftIO getCurrentTime
+		tz <- liftIO $ getTimeZone now
+		if now >= localTimeToUTC tz windowstart && now <= localTimeToUTC tz windowend
+			then do
+				let nowt = utcToLocalTime tz now
+				runActivity urlrenderer activity nowt
+				loop (Just nowt)
+			else loop lasttime
+	go _ = noop -- running at exact time not handled here
+	loop = remoteActivityThread urlrenderer mvar activity
+
+secondsUntilLocalTime :: LocalTime -> IO Seconds
+secondsUntilLocalTime t = do
+	now <- getCurrentTime
+	tz <- getTimeZone now
+	let secs = truncate $ diffUTCTime (localTimeToUTC tz t) now
+	return $ if secs > 0
+		then Seconds secs
+		else Seconds 0
+
+runActivity :: UrlRenderer -> ScheduledActivity -> LocalTime -> Assistant ()
+runActivity urlrenderer activity nowt = do
+	debug ["starting", desc]
+	runActivity' urlrenderer activity
+	debug ["finished", desc]
+	liftAnnex $ setLastRunTime activity nowt
+  where
+	desc = fromScheduledActivity activity
+
+runActivity' :: UrlRenderer -> ScheduledActivity -> Assistant ()
+runActivity' urlrenderer (ScheduledSelfFsck _ d) = do
+	program <- liftIO $ readProgramFile
+	g <- liftAnnex gitRepo
+	fsckresults <- showFscking urlrenderer Nothing $ tryNonAsync $ do
+		void $ batchCommand program (Param "fsck" : annexFsckParams d)
+		Git.Fsck.findBroken True g
+	u <- liftAnnex getUUID
+	void $ repairWhenNecessary urlrenderer u Nothing fsckresults
+	mapM_ reget =<< liftAnnex (dirKeys gitAnnexBadDir)
+  where
+	reget k = queueTransfers "fsck found bad file; redownloading" Next k Nothing Download
+runActivity' urlrenderer (ScheduledRemoteFsck u s d) = dispatch =<< liftAnnex (remoteFromUUID u)
+  where
+	dispatch Nothing = debug ["skipping remote fsck of uuid without a configured remote", fromUUID u, fromSchedule s]
+	dispatch (Just rmt) = void $ case Remote.remoteFsck rmt of
+		Nothing -> go rmt $ do
+			program <- readProgramFile
+			void $ batchCommand program $ 
+				[ Param "fsck"
+				-- avoid downloading files
+				, Param "--fast"
+				, Param "--from"
+				, Param $ Remote.name rmt
+				] ++ annexFsckParams d
+		Just mkfscker -> do
+			{- Note that having mkfsker return an IO action
+			 - avoids running a long duration fsck in the
+			 - Annex monad. -}
+			go rmt =<< liftAnnex (mkfscker (annexFsckParams d))
+	go rmt annexfscker = do
+		fsckresults <- showFscking urlrenderer (Just rmt) $ tryNonAsync $ do
+			void annexfscker
+			let r = Remote.repo rmt
+			if Git.repoIsLocal r && not (Git.repoIsLocalUnknown r)
+				then Just <$> Git.Fsck.findBroken True r
+				else pure Nothing
+		maybe noop (void . repairWhenNecessary urlrenderer u (Just rmt)) fsckresults
+
+annexFsckParams :: Duration -> [CommandParam]
+annexFsckParams d =
+	[ Param "--incremental-schedule=1d"
+	, Param $ "--time-limit=" ++ fromDuration d
+	]

Assistant/Threads/DaemonStatus.hs

@@ -0,0 +1,29 @@
+{- git-annex assistant daemon status thread
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.Threads.DaemonStatus where
+
+import Assistant.Common
+import Assistant.DaemonStatus
+import Utility.ThreadScheduler
+import Utility.NotificationBroadcaster
+
+{- This writes the daemon status to disk, when it changes, but no more
+ - frequently than once every ten minutes.
+ -}
+daemonStatusThread :: NamedThread
+daemonStatusThread = namedThread "DaemonStatus" $ do
+	notifier <- liftIO . newNotificationHandle False
+		=<< changeNotifier <$> getDaemonStatus
+	checkpoint
+	runEvery (Seconds tenMinutes) <~> do
+		liftIO $ waitNotification notifier
+		checkpoint
+  where
+	checkpoint = do
+		file <- liftAnnex $ fromRepo gitAnnexDaemonStatusFile
+		liftIO . writeDaemonStatusFile file =<< getDaemonStatus

Assistant/Threads/Glacier.hs

@@ -0,0 +1,43 @@
+{- git-annex assistant Amazon Glacier retrieval
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+{-# LANGUAGE OverloadedStrings #-}
+
+module Assistant.Threads.Glacier where
+
+import Assistant.Common
+import Utility.ThreadScheduler
+import qualified Types.Remote as Remote
+import qualified Remote.Glacier as Glacier
+import Logs.Transfer
+import Assistant.DaemonStatus
+import Assistant.TransferQueue
+
+import qualified Data.Set as S
+
+{- Wakes up every half hour and checks if any glacier remotes have failed
+ - downloads. If so, runs glacier-cli to check if the files are now
+ - available, and queues the downloads. -}
+glacierThread :: NamedThread
+glacierThread = namedThread "Glacier" $ runEvery (Seconds 3600) <~> go
+  where
+	isglacier r = Remote.remotetype r == Glacier.remote
+	go = do
+		rs <- filter isglacier . syncDataRemotes <$> getDaemonStatus
+		forM_ rs $ \r -> 
+			check r =<< liftAnnex (getFailedTransfers $ Remote.uuid r)
+	check _ [] = noop
+	check r l = do
+		let keys = map getkey l
+		(availkeys, failedkeys) <- liftAnnex $ Glacier.jobList r keys
+		let s = S.fromList (failedkeys ++ availkeys)
+		let l' = filter (\p -> S.member (getkey p) s) l
+		forM_ l' $ \(t, info) -> do
+			liftAnnex $ removeFailedTransfer t
+			queueTransferWhenSmall "object available from glacier" (associatedFile info) t r
+	getkey = transferKey . fst

Assistant/Threads/Merger.hs

@@ -0,0 +1,119 @@
+{- git-annex assistant git merge thread
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.Threads.Merger where
+
+import Assistant.Common
+import Assistant.TransferQueue
+import Assistant.BranchChange
+import Assistant.DaemonStatus
+import Assistant.ScanRemotes
+import Utility.DirWatcher
+import Utility.DirWatcher.Types
+import qualified Annex.Branch
+import qualified Git
+import qualified Git.Branch
+import Annex.AutoMerge
+import Annex.TaggedPush
+import Remote (remoteFromUUID)
+
+import qualified Data.Set as S
+import qualified Data.Text as T
+
+{- This thread watches for changes to .git/refs/, and handles incoming
+ - pushes. -}
+mergeThread :: NamedThread
+mergeThread = namedThread "Merger" $ do
+	g <- liftAnnex gitRepo
+	let dir = Git.localGitDir g </> "refs"
+	liftIO $ createDirectoryIfMissing True dir
+	let hook a = Just <$> asIO2 (runHandler a)
+	changehook <- hook onChange
+	errhook <- hook onErr
+	let hooks = mkWatchHooks
+		{ addHook = changehook
+		, modifyHook = changehook
+		, errHook = errhook
+		}
+	void $ liftIO $ watchDir dir (const False) True hooks id
+	debug ["watching", dir]
+
+type Handler = FilePath -> Assistant ()
+
+{- Runs an action handler.
+ -
+ - Exceptions are ignored, otherwise a whole thread could be crashed.
+ -}
+runHandler :: Handler -> FilePath -> Maybe FileStatus -> Assistant ()
+runHandler handler file _filestatus =
+	either (liftIO . print) (const noop) =<< tryIO <~> handler file
+
+{- Called when there's an error with inotify. -}
+onErr :: Handler
+onErr = error
+
+{- Called when a new branch ref is written, or a branch ref is modified.
+ -
+ - At startup, synthetic add events fire, causing this to run, but that's
+ - ok; it ensures that any changes pushed since the last time the assistant
+ - ran are merged in.
+ -}
+onChange :: Handler
+onChange file
+	| ".lock" `isSuffixOf` file = noop
+	| isAnnexBranch file = do
+		branchChanged
+		diverged <- liftAnnex Annex.Branch.forceUpdate
+		when diverged $
+			unlessM handleDesynced $
+				queueDeferredDownloads "retrying deferred download" Later
+	| "/synced/" `isInfixOf` file =
+		mergecurrent =<< liftAnnex (inRepo Git.Branch.current)
+	| otherwise = noop
+  where
+	changedbranch = fileToBranch file
+
+	mergecurrent (Just current)
+		| equivBranches changedbranch current =
+			whenM (liftAnnex $ inRepo $ Git.Branch.changed current changedbranch) $ do
+				debug
+					[ "merging", Git.fromRef changedbranch
+					, "into", Git.fromRef current
+					]
+				void $ liftAnnex $ autoMergeFrom changedbranch (Just current) Git.Branch.AutomaticCommit
+	mergecurrent _ = noop
+
+	handleDesynced = case fromTaggedBranch changedbranch of
+		Nothing -> return False
+		Just (u, info) -> do
+			mr <- liftAnnex $ remoteFromUUID u
+			case mr of
+				Nothing -> return False
+				Just r -> do
+					s <- desynced <$> getDaemonStatus
+					if S.member u s || Just (T.unpack $ getXMPPClientID r) == info
+						then do
+							modifyDaemonStatus_ $ \st -> st
+								{ desynced = S.delete u s }
+							addScanRemotes True [r]
+							return True
+						else return False
+
+equivBranches :: Git.Ref -> Git.Ref -> Bool
+equivBranches x y = base x == base y
+  where
+	base = takeFileName . Git.fromRef
+
+isAnnexBranch :: FilePath -> Bool
+isAnnexBranch f = n `isSuffixOf` f
+  where
+	n = '/' : Git.fromRef Annex.Branch.name
+
+fileToBranch :: FilePath -> Git.Ref
+fileToBranch f = Git.Ref $ "refs" </> base
+  where
+	base = Prelude.last $ split "/refs/" f

Assistant/Threads/MountWatcher.hs

@@ -0,0 +1,199 @@
+{- git-annex assistant mount watcher, using either dbus or mtab polling
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+{-# LANGUAGE OverloadedStrings #-}
+
+module Assistant.Threads.MountWatcher where
+
+import Assistant.Common
+import Assistant.DaemonStatus
+import Assistant.Sync
+import qualified Annex
+import qualified Git
+import Utility.ThreadScheduler
+import Utility.Mounts
+import Remote.List
+import qualified Types.Remote as Remote
+import Assistant.Types.UrlRenderer
+import Assistant.Fsck
+
+import qualified Data.Set as S
+
+#if WITH_DBUS
+import Utility.DBus
+import DBus.Client
+import DBus
+import Data.Word (Word32)
+import Control.Concurrent
+import qualified Control.Exception as E
+#else
+#warning Building without dbus support; will use mtab polling
+#endif
+
+mountWatcherThread :: UrlRenderer -> NamedThread
+mountWatcherThread urlrenderer = namedThread "MountWatcher" $
+#if WITH_DBUS
+	dbusThread urlrenderer
+#else
+	pollingThread urlrenderer
+#endif
+
+#if WITH_DBUS
+
+dbusThread :: UrlRenderer -> Assistant ()
+dbusThread urlrenderer = do
+	runclient <- asIO1 go
+	r <- liftIO $ E.try $ runClient getSessionAddress runclient
+	either onerr (const noop) r
+  where
+	go client = ifM (checkMountMonitor client)
+		( do
+			{- Store the current mount points in an MVar, to be
+			 - compared later. We could in theory work out the
+			 - mount point from the dbus message, but this is
+			 - easier. -}
+			mvar <- liftIO $ newMVar =<< currentMountPoints
+			handleevent <- asIO1 $ \_event -> do
+				nowmounted <- liftIO $ currentMountPoints
+				wasmounted <- liftIO $ swapMVar mvar nowmounted
+				handleMounts urlrenderer wasmounted nowmounted
+			liftIO $ forM_ mountChanged $ \matcher ->
+#if MIN_VERSION_dbus(0,10,7)
+				void $ addMatch client matcher handleevent
+#else
+				listen client matcher handleevent
+#endif
+		, do
+			liftAnnex $
+				warning "No known volume monitor available through dbus; falling back to mtab polling"
+			pollingThread urlrenderer
+		)
+	onerr :: E.SomeException -> Assistant ()
+	onerr e = do
+		{- If the session dbus fails, the user probably
+		 - logged out of their desktop. Even if they log
+		 - back in, we won't have access to the dbus
+		 - session key, so polling is the best that can be
+		 - done in this situation. -}
+		liftAnnex $
+			warning $ "dbus failed; falling back to mtab polling (" ++ show e ++ ")"
+		pollingThread urlrenderer
+
+{- Examine the list of services connected to dbus, to see if there
+ - are any we can use to monitor mounts. If not, will attempt to start one. -}
+checkMountMonitor :: Client -> Assistant Bool
+checkMountMonitor client = do
+	running <- filter (`elem` usableservices)
+		<$> liftIO (listServiceNames client)
+	case running of
+		[] -> startOneService client startableservices
+		(service:_) -> do
+			debug [ "Using running DBUS service"
+				, service
+				, "to monitor mount events."
+				]
+			return True
+  where
+	startableservices = [gvfs, gvfsgdu]
+	usableservices = startableservices ++ [kde]
+	gvfs = "org.gtk.Private.UDisks2VolumeMonitor"
+	gvfsgdu = "org.gtk.Private.GduVolumeMonitor"
+	kde = "org.kde.DeviceNotifications"
+
+startOneService :: Client -> [ServiceName] -> Assistant Bool
+startOneService _ [] = return False
+startOneService client (x:xs) = do
+	_ <- liftIO $ tryNonAsync $ callDBus client "StartServiceByName"
+		[toVariant x, toVariant (0 :: Word32)]
+	ifM (liftIO $ elem x <$> listServiceNames client)
+		( do
+			debug
+				[ "Started DBUS service", x
+				, "to monitor mount events."
+				]
+			return True
+		, startOneService client xs
+		)
+
+{- Filter matching events recieved when drives are mounted and unmounted. -}	
+mountChanged :: [MatchRule]
+mountChanged = [gvfs True, gvfs False, kde, kdefallback]
+  where
+	{- gvfs reliably generates this event whenever a
+	 - drive is mounted/unmounted, whether automatically, or manually -}
+	gvfs mount = matchAny
+		{ matchInterface = Just "org.gtk.Private.RemoteVolumeMonitor"
+		, matchMember = Just $ if mount then "MountAdded" else "MountRemoved"
+		}
+	{- This event fires when KDE prompts the user what to do with a drive,
+	 - but maybe not at other times. And it's not received -}
+	kde = matchAny
+		{ matchInterface = Just "org.kde.Solid.Device"
+		, matchMember = Just "setupDone"
+		}
+	{- This event may not be closely related to mounting a drive, but it's
+	 - observed reliably when a drive gets mounted or unmounted. -}
+	kdefallback = matchAny
+		{ matchInterface = Just "org.kde.KDirNotify"
+		, matchMember = Just "enteredDirectory"
+		}
+
+#endif
+
+pollingThread :: UrlRenderer -> Assistant ()
+pollingThread urlrenderer = go =<< liftIO currentMountPoints
+  where
+	go wasmounted = do
+		liftIO $ threadDelaySeconds (Seconds 10)
+		nowmounted <- liftIO currentMountPoints
+		handleMounts urlrenderer wasmounted nowmounted
+		go nowmounted
+
+handleMounts :: UrlRenderer -> MountPoints -> MountPoints -> Assistant ()
+handleMounts urlrenderer wasmounted nowmounted =
+	mapM_ (handleMount urlrenderer . mnt_dir) $
+		S.toList $ newMountPoints wasmounted nowmounted
+
+handleMount :: UrlRenderer -> FilePath -> Assistant ()
+handleMount urlrenderer dir = do
+	debug ["detected mount of", dir]
+	rs <- filter (Git.repoIsLocal . Remote.repo) <$> remotesUnder dir
+	mapM_ (fsckNudge urlrenderer . Just) rs
+	reconnectRemotes True rs
+
+{- Finds remotes located underneath the mount point.
+ -
+ - Updates state to include the remotes.
+ -
+ - The config of git remotes is re-read, as it may not have been available
+ - at startup time, or may have changed (it could even be a different
+ - repository at the same remote location..)
+ -}
+remotesUnder :: FilePath -> Assistant [Remote]
+remotesUnder dir = do
+	repotop <- liftAnnex $ fromRepo Git.repoPath
+	rs <- liftAnnex remoteList
+	pairs <- liftAnnex $ mapM (checkremote repotop) rs
+	let (waschanged, rs') = unzip pairs
+	when (or waschanged) $ do
+		liftAnnex $ Annex.changeState $ \s -> s { Annex.remotes = catMaybes rs' }
+		updateSyncRemotes
+	return $ mapMaybe snd $ filter fst pairs
+  where
+	checkremote repotop r = case Remote.localpath r of
+		Just p | dirContains dir (absPathFrom repotop p) ->
+			(,) <$> pure True <*> updateRemote r
+		_ -> return (False, Just r)
+
+type MountPoints = S.Set Mntent
+
+currentMountPoints :: IO MountPoints
+currentMountPoints = S.fromList <$> getMounts
+
+newMountPoints :: MountPoints -> MountPoints -> MountPoints
+newMountPoints old new = S.difference new old

Assistant/Threads/NetWatcher.hs

@@ -0,0 +1,184 @@
+{- git-annex assistant network connection watcher, using dbus
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+{-# LANGUAGE OverloadedStrings #-}
+
+module Assistant.Threads.NetWatcher where
+
+import Assistant.Common
+import Assistant.Sync
+import Utility.ThreadScheduler
+import qualified Types.Remote as Remote
+import Assistant.DaemonStatus
+import Utility.NotificationBroadcaster
+
+#if WITH_DBUS
+import Assistant.RemoteControl
+import Utility.DBus
+import DBus.Client
+import DBus
+import Assistant.NetMessager
+#else
+#ifdef linux_HOST_OS
+#warning Building without dbus support; will poll for network connection changes
+#endif
+#endif
+
+netWatcherThread :: NamedThread
+#if WITH_DBUS
+netWatcherThread = thread dbusThread
+#else
+netWatcherThread = thread noop
+#endif
+  where
+	thread = namedThread "NetWatcher"
+
+{- This is a fallback for when dbus cannot be used to detect
+ - network connection changes, but it also ensures that
+ - any networked remotes that may have not been routable for a
+ - while (despite the local network staying up), are synced with
+ - periodically.
+ -
+ - Note that it does not call notifyNetMessagerRestart, or
+ - signal the RemoteControl, because it doesn't know that the
+ - network has changed.
+ -}
+netWatcherFallbackThread :: NamedThread
+netWatcherFallbackThread = namedThread "NetWatcherFallback" $
+	runEvery (Seconds 3600) <~> handleConnection
+
+#if WITH_DBUS
+
+dbusThread :: Assistant ()
+dbusThread = do
+	handleerr <- asIO2 onerr
+	runclient <- asIO1 go
+	liftIO $ persistentClient getSystemAddress () handleerr runclient
+  where
+	go client = ifM (checkNetMonitor client)
+		( do
+			callback <- asIO1 connchange
+			liftIO $ do
+				listenNMConnections client callback
+				listenWicdConnections client callback
+		, do
+			liftAnnex $
+				warning "No known network monitor available through dbus; falling back to polling"
+		)
+	connchange False = do
+		debug ["detected network disconnection"]
+		sendRemoteControl LOSTNET
+	connchange True = do
+		debug ["detected network connection"]
+		notifyNetMessagerRestart
+		handleConnection
+		sendRemoteControl RESUME
+	onerr e _ = do
+		liftAnnex $
+			warning $ "lost dbus connection; falling back to polling (" ++ show e ++ ")"
+		{- Wait, in hope that dbus will come back -}
+		liftIO $ threadDelaySeconds (Seconds 60)
+
+{- Examine the list of services connected to dbus, to see if there
+ - are any we can use to monitor network connections. -}
+checkNetMonitor :: Client -> Assistant Bool
+checkNetMonitor client = do
+	running <- liftIO $ filter (`elem` [networkmanager, wicd])
+		<$> listServiceNames client
+	case running of
+		[] -> return False
+		(service:_) -> do
+			debug [ "Using running DBUS service"
+				, service
+				, "to monitor network connection events."
+				]
+			return True
+  where
+	networkmanager = "org.freedesktop.NetworkManager"
+	wicd = "org.wicd.daemon"
+
+{- Listens for NetworkManager connections and diconnections.
+ -
+ - Connection example (once fully connected):
+ - [Variant {"ActivatingConnection": Variant (ObjectPath "/"), "PrimaryConnection": Variant (ObjectPath "/org/freedesktop/NetworkManager/ActiveConnection/34"), "State": Variant 70}]
+ -
+ - Disconnection example:
+ - [Variant {"ActiveConnections": Variant []}]
+ -}
+listenNMConnections :: Client -> (Bool -> IO ()) -> IO ()
+listenNMConnections client setconnected =
+#if MIN_VERSION_dbus(0,10,7)
+	void $ addMatch client matcher
+#else
+	listen client matcher
+#endif
+		$ \event -> mapM_ handleevent
+			(map dictionaryItems $ mapMaybe fromVariant $ signalBody event)
+  where
+	matcher = matchAny
+		{ matchInterface = Just "org.freedesktop.NetworkManager"
+		, matchMember = Just "PropertiesChanged"
+		}
+	nm_active_connections_key = toVariant ("ActiveConnections" :: String)
+	nm_activatingconnection_key = toVariant ("ActivatingConnection" :: String)
+	noconnections = Just $ toVariant $ toVariant ([] :: [ObjectPath])
+	rootconnection = Just $ toVariant $ toVariant $ objectPath_ "/"
+	handleevent m
+		| lookup nm_active_connections_key m == noconnections =
+			setconnected False
+		| lookup nm_activatingconnection_key m == rootconnection =
+			setconnected True
+		| otherwise = noop
+
+{- Listens for Wicd connections and disconnections.
+ -
+ - Connection example:
+ -   ConnectResultsSent:
+ -     Variant "success"
+ -
+ - Diconnection example:
+ -   StatusChanged
+ -     [Variant 0, Variant [Varient ""]]
+ -}
+listenWicdConnections :: Client -> (Bool -> IO ()) -> IO ()
+listenWicdConnections client setconnected = do
+	match connmatcher $ \event ->
+		when (any (== wicd_success) (signalBody event)) $
+			setconnected True
+	match statusmatcher $ \event -> handleevent (signalBody event)
+  where
+	connmatcher = matchAny
+		{ matchInterface = Just "org.wicd.daemon"
+		, matchMember = Just "ConnectResultsSent"
+		}
+	statusmatcher = matchAny
+		{ matchInterface = Just "org.wicd.daemon"
+		, matchMember = Just "StatusChanged"
+		}
+	wicd_success = toVariant ("success" :: String)
+	wicd_disconnected = toVariant [toVariant ("" :: String)]
+	handleevent status
+		| any (== wicd_disconnected) status = setconnected False
+		| otherwise = noop
+	match matcher a = 
+#if MIN_VERSION_dbus(0,10,7)
+		void $ addMatch client matcher a
+#else
+		listen client matcher a
+#endif
+#endif
+
+handleConnection :: Assistant ()
+handleConnection = do
+	liftIO . sendNotification . networkConnectedNotifier =<< getDaemonStatus
+	reconnectRemotes True =<< networkRemotes
+
+{- Network remotes to sync with. -}
+networkRemotes :: Assistant [Remote]
+networkRemotes = filter (isNothing . Remote.localpath) . syncRemotes
+	<$> getDaemonStatus

Assistant/Threads/PairListener.hs

@@ -0,0 +1,151 @@
+{- git-annex assistant thread to listen for incoming pairing traffic
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.Threads.PairListener where
+
+import Assistant.Common
+import Assistant.Pairing
+import Assistant.Pairing.Network
+import Assistant.Pairing.MakeRemote
+import Assistant.WebApp (UrlRenderer)
+import Assistant.WebApp.Types
+import Assistant.Alert
+import Assistant.DaemonStatus
+import Utility.ThreadScheduler
+import Git
+
+import Network.Multicast
+import Network.Socket
+import qualified Data.Text as T
+
+pairListenerThread :: UrlRenderer -> NamedThread
+pairListenerThread urlrenderer = namedThread "PairListener" $ do
+	listener <- asIO1 $ go [] []
+	liftIO $ withSocketsDo $
+		runEvery (Seconds 60) $ void $ tryIO $ 
+			listener =<< getsock
+  where
+	{- Note this can crash if there's no network interface,
+	 - or only one like lo that doesn't support multicast. -}
+	getsock = multicastReceiver (multicastAddress $ IPv4Addr undefined) pairingPort
+		
+	go reqs cache sock = liftIO (getmsg sock []) >>= \msg -> case readish msg of
+		Nothing -> go reqs cache sock
+		Just m -> do
+			debug ["received", show msg]
+			(pip, verified) <- verificationCheck m
+				=<< (pairingInProgress <$> getDaemonStatus)
+			let wrongstage = maybe False (\p -> pairMsgStage m <= inProgressPairStage p) pip
+			let fromus = maybe False (\p -> remoteSshPubKey (pairMsgData m) == remoteSshPubKey (inProgressPairData p)) pip
+			case (wrongstage, fromus, checkSane (pairMsgData m), pairMsgStage m) of
+				(_, True, _, _) -> do
+					debug ["ignoring message that looped back"]
+					go reqs cache sock
+				(_, _, False, _) -> do
+					liftAnnex $ warning
+						"illegal control characters in pairing message; ignoring"
+					go reqs cache sock
+				-- PairReq starts a pairing process, so a
+				-- new one is always heeded, even if
+				-- some other pairing is in process.
+				(_, _, _, PairReq) -> if m `elem` reqs
+					then go reqs (invalidateCache m cache) sock
+					else do
+						pairReqReceived verified urlrenderer m
+						go (m:take 10 reqs) (invalidateCache m cache) sock
+				(True, _, _, _) -> do
+					debug
+						["ignoring out of order message"
+						, show (pairMsgStage m)
+						, "expected"
+						, show (succ . inProgressPairStage <$> pip)
+						]
+					go reqs cache sock
+				(_, _, _, PairAck) -> do
+					cache' <- pairAckReceived verified pip m cache
+					go reqs cache' sock
+				(_,_ , _, PairDone) -> do
+					pairDoneReceived verified pip m
+					go reqs cache sock
+
+	{- As well as verifying the message using the shared secret,
+	 - check its UUID against the UUID we have stored. If
+	 - they're the same, someone is sending bogus messages,
+	 - which could be an attempt to brute force the shared secret. -}
+	verificationCheck _ Nothing = return (Nothing, False)
+	verificationCheck m (Just pip)
+		| not verified && sameuuid = do
+			liftAnnex $ warning
+				"detected possible pairing brute force attempt; disabled pairing"
+			stopSending pip
+			return (Nothing, False)
+		| otherwise = return (Just pip, verified && sameuuid)
+	  where
+		verified = verifiedPairMsg m pip
+		sameuuid = pairUUID (inProgressPairData pip) == pairUUID (pairMsgData m)
+
+	{- PairReqs invalidate the cache of recently finished pairings.
+	 - This is so that, if a new pairing is started with the
+	 - same secret used before, a bogus PairDone is not sent. -}
+	invalidateCache msg = filter (not . verifiedPairMsg msg)
+
+	getmsg sock c = do
+		(msg, n, _) <- recvFrom sock chunksz
+		if n < chunksz
+			then return $ c ++ msg
+			else getmsg sock $ c ++ msg
+	  where
+		chunksz = 1024
+
+{- Show an alert when a PairReq is seen. -}
+pairReqReceived :: Bool -> UrlRenderer -> PairMsg -> Assistant ()
+pairReqReceived True _ _ = noop -- ignore our own PairReq
+pairReqReceived False urlrenderer msg = do
+	button <- mkAlertButton True (T.pack "Respond") urlrenderer (FinishLocalPairR msg)
+	void $ addAlert $ pairRequestReceivedAlert repo button
+  where
+	repo = pairRepo msg
+
+{- When a verified PairAck is seen, a host is ready to pair with us, and has
+ - already configured our ssh key. Stop sending PairReqs, finish the pairing,
+ - and send a single PairDone. -}
+pairAckReceived :: Bool -> Maybe PairingInProgress -> PairMsg -> [PairingInProgress] -> Assistant [PairingInProgress]
+pairAckReceived True (Just pip) msg cache = do
+	stopSending pip
+	repodir <- repoPath <$> liftAnnex gitRepo
+	liftIO $ setupAuthorizedKeys msg repodir
+	finishedLocalPairing msg (inProgressSshKeyPair pip)
+	startSending pip PairDone $ multicastPairMsg
+		(Just 1) (inProgressSecret pip) (inProgressPairData pip)
+	return $ pip : take 10 cache
+{- A stale PairAck might also be seen, after we've finished pairing.
+ - Perhaps our PairDone was not received. To handle this, we keep
+ - a cache of recently finished pairings, and re-send PairDone in
+ - response to stale PairAcks for them. -}
+pairAckReceived _ _ msg cache = do
+	let pips = filter (verifiedPairMsg msg) cache
+	unless (null pips) $
+		forM_ pips $ \pip ->
+			startSending pip PairDone $ multicastPairMsg
+				(Just 1) (inProgressSecret pip) (inProgressPairData pip)
+	return cache
+
+{- If we get a verified PairDone, the host has accepted our PairAck, and
+ - has paired with us. Stop sending PairAcks, and finish pairing with them.
+ -
+ - TODO: Should third-party hosts remove their pair request alert when they
+ - see a PairDone?
+ - Complication: The user could have already clicked on the alert and be
+ - entering the secret. Would be better to start a fresh pair request in this
+ - situation.
+ -}
+pairDoneReceived :: Bool -> Maybe PairingInProgress -> PairMsg -> Assistant ()
+pairDoneReceived False _ _ = noop -- not verified
+pairDoneReceived True Nothing _ = noop -- not in progress
+pairDoneReceived True (Just pip) msg = do
+	stopSending pip
+	finishedLocalPairing msg (inProgressSshKeyPair pip)

Assistant/Threads/ProblemFixer.hs

@@ -0,0 +1,70 @@
+{- git-annex assistant thread to handle fixing problems with repositories
+ -
+ - Copyright 2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.Threads.ProblemFixer (
+	problemFixerThread
+) where
+
+import Assistant.Common
+import Assistant.Types.RepoProblem
+import Assistant.RepoProblem
+import Assistant.Types.UrlRenderer
+import Assistant.Alert
+import Remote
+import qualified Types.Remote as Remote
+import qualified Git.Fsck
+import Assistant.Repair
+import qualified Git
+import Annex.UUID
+import Utility.ThreadScheduler
+
+{- Waits for problems with a repo, and tries to fsck the repo and repair
+ - the problem. -}
+problemFixerThread :: UrlRenderer -> NamedThread
+problemFixerThread urlrenderer = namedThread "ProblemFixer" $
+	go =<< getRepoProblems
+  where
+	go problems = do
+		mapM_ (handleProblem urlrenderer) problems
+		liftIO $ threadDelaySeconds (Seconds 60)
+		-- Problems may have been re-reported while they were being
+		-- fixed, so ignore those. If a new unique problem happened
+		-- 60 seconds after the last was fixed, we're unlikely
+		-- to do much good anyway.
+		go =<< filter (\p -> not (any (sameRepoProblem p) problems))
+			<$> getRepoProblems
+
+handleProblem :: UrlRenderer -> RepoProblem -> Assistant ()
+handleProblem urlrenderer repoproblem = do
+	fixed <- ifM ((==) (problemUUID repoproblem) <$> liftAnnex getUUID)
+		( handleLocalRepoProblem urlrenderer
+		, maybe (return False) (handleRemoteProblem urlrenderer)
+			=<< liftAnnex (remoteFromUUID $ problemUUID repoproblem)
+		)
+	when fixed $
+		liftIO $ afterFix repoproblem
+
+handleRemoteProblem :: UrlRenderer -> Remote -> Assistant Bool
+handleRemoteProblem urlrenderer rmt
+	| Git.repoIsLocal r && not (Git.repoIsLocalUnknown r) =
+		ifM (liftIO $ checkAvailable True rmt)
+			( do
+				fixedlocks <- repairStaleGitLocks r
+				fsckresults <- showFscking urlrenderer (Just rmt) $ tryNonAsync $
+					Git.Fsck.findBroken True r
+				repaired <- repairWhenNecessary urlrenderer (Remote.uuid rmt) (Just rmt) fsckresults
+				return $ fixedlocks || repaired
+			, return False
+			)
+	| otherwise = return False
+  where
+	r = Remote.repo rmt
+
+{- This is not yet used, and should probably do a fsck. -}
+handleLocalRepoProblem :: UrlRenderer -> Assistant Bool
+handleLocalRepoProblem _urlrenderer = do
+	repairStaleGitLocks =<< liftAnnex gitRepo

Assistant/Threads/Pusher.hs

@@ -0,0 +1,49 @@
+{- git-annex assistant git pushing thread
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.Threads.Pusher where
+
+import Assistant.Common
+import Assistant.Commits
+import Assistant.Pushes
+import Assistant.DaemonStatus
+import Assistant.Sync
+import Utility.ThreadScheduler
+import qualified Remote
+import qualified Types.Remote as Remote
+
+{- This thread retries pushes that failed before. -}
+pushRetryThread :: NamedThread
+pushRetryThread = namedThread "PushRetrier" $ runEvery (Seconds halfhour) <~> do
+	-- We already waited half an hour, now wait until there are failed
+	-- pushes to retry.
+	topush <- getFailedPushesBefore (fromIntegral halfhour)
+	unless (null topush) $ do
+		debug ["retrying", show (length topush), "failed pushes"]
+		void $ pushToRemotes True topush
+  where
+	halfhour = 1800
+
+{- This thread pushes git commits out to remotes soon after they are made. -}
+pushThread :: NamedThread
+pushThread = namedThread "Pusher" $ runEvery (Seconds 2) <~> do
+	-- We already waited two seconds as a simple rate limiter.
+	-- Next, wait until at least one commit has been made
+	void getCommits
+	-- Now see if now's a good time to push.
+	void $ pushToRemotes True =<< pushTargets
+
+{- We want to avoid pushing to remotes that are marked readonly.
+ -
+ - Also, avoid pushing to local remotes we can easily tell are not available,
+ - to avoid ugly messages when a removable drive is not attached.
+ -}
+pushTargets :: Assistant [Remote]
+pushTargets = liftIO . filterM (Remote.checkAvailable True)
+	=<< candidates <$> getDaemonStatus
+  where
+	candidates = filter (not . Remote.readonly) . syncGitRemotes

Assistant/Threads/RemoteControl.hs

@@ -0,0 +1,121 @@
+{- git-annex assistant communication with remotedaemon
+ -
+ - Copyright 2014 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.Threads.RemoteControl where
+
+import Assistant.Common
+import RemoteDaemon.Types
+import Config.Files
+import Utility.Batch
+import Utility.SimpleProtocol
+import Assistant.Alert
+import Assistant.Alert.Utility
+import Assistant.DaemonStatus
+import qualified Git
+import qualified Git.Types as Git
+import qualified Remote
+import qualified Types.Remote as Remote
+
+import Control.Concurrent
+import Control.Concurrent.Async
+import Network.URI
+import qualified Data.Map as M
+import qualified Data.Set as S
+
+remoteControlThread :: NamedThread
+remoteControlThread = namedThread "RemoteControl" $ do
+	program <- liftIO readProgramFile
+	(cmd, params) <- liftIO $ toBatchCommand
+		(program, [Param "remotedaemon"])
+	let p = proc cmd (toCommand params)
+	(Just toh, Just fromh, _, pid) <- liftIO $ createProcess p
+		{ std_in = CreatePipe
+		, std_out = CreatePipe
+		}
+	
+	urimap <- liftIO . newMVar =<< liftAnnex getURIMap
+
+	controller <- asIO $ remoteControllerThread toh
+	responder <- asIO $ remoteResponderThread fromh urimap
+
+	-- run controller and responder until the remotedaemon dies
+	liftIO $ void $ tryNonAsync $ controller `concurrently` responder
+	debug ["remotedaemon exited"]
+	liftIO $ forceSuccessProcess p pid
+
+-- feed from the remoteControl channel into the remotedaemon
+remoteControllerThread :: Handle -> Assistant ()
+remoteControllerThread toh = do
+	clicker <- getAssistant remoteControl
+	forever $ do
+		msg <- liftIO $ readChan clicker
+		debug [show msg]
+		liftIO $ do
+			hPutStrLn toh $ unwords $ formatMessage msg
+			hFlush toh
+
+-- read status messages emitted by the remotedaemon and handle them
+remoteResponderThread :: Handle -> MVar (M.Map URI Remote) -> Assistant ()
+remoteResponderThread fromh urimap = go M.empty
+  where
+	go syncalerts = do
+		l <- liftIO $ hGetLine fromh
+		debug [l]
+		case parseMessage l of
+			Just (CONNECTED uri) -> changeconnected S.insert uri
+			Just (DISCONNECTED uri) -> changeconnected S.delete uri
+			Just (SYNCING uri) -> withr uri $ \r ->
+				if M.member (Remote.uuid r) syncalerts
+					then go syncalerts
+					else do
+						i <- addAlert $ syncAlert [r]
+						go (M.insert (Remote.uuid r) i syncalerts)
+			Just (DONESYNCING uri status) -> withr uri $ \r ->
+				case M.lookup (Remote.uuid r) syncalerts of
+					Nothing -> cont
+					Just i -> do
+						let (succeeded, failed) = if status
+							then ([r], [])
+							else ([], [r])
+						updateAlertMap $ mergeAlert i $
+							syncResultAlert succeeded failed
+						go (M.delete (Remote.uuid r) syncalerts)
+			Just (WARNING (RemoteURI uri) msg) -> do
+				void $ addAlert $
+					warningAlert ("RemoteControl "++ show uri) msg
+				cont
+			Nothing -> do
+				debug ["protocol error from remotedaemon: ", l]
+				cont
+	  where
+		cont = go syncalerts
+		withr uri = withRemote uri urimap cont
+		changeconnected sm uri = withr uri $ \r -> do
+			changeCurrentlyConnected $ sm $ Remote.uuid r
+			cont
+
+getURIMap :: Annex (M.Map URI Remote)
+getURIMap = Remote.remoteMap' id (mkk . Git.location . Remote.repo)
+  where
+	mkk (Git.Url u) = Just u
+	mkk _ = Nothing
+
+withRemote
+	:: RemoteURI
+	-> MVar (M.Map URI Remote)
+	-> Assistant a
+	-> (Remote -> Assistant a)
+	-> Assistant a
+withRemote (RemoteURI uri) remotemap noremote a = do
+	m <- liftIO $ readMVar remotemap
+	case M.lookup uri m of
+		Just r -> a r
+		Nothing -> do
+			{- Reload map, in case a new remote has been added. -}
+			m' <- liftAnnex getURIMap
+			void $ liftIO $ swapMVar remotemap $ m'
+			maybe noremote a (M.lookup uri m')

Assistant/Threads/SanityChecker.hs

@@ -0,0 +1,327 @@
+{- git-annex assistant sanity checker
+ -
+ - Copyright 2012, 2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Assistant.Threads.SanityChecker (
+	sanityCheckerStartupThread,
+	sanityCheckerDailyThread,
+	sanityCheckerHourlyThread
+) where
+
+import Assistant.Common
+import Assistant.DaemonStatus
+import Assistant.Alert
+import Assistant.Repair
+import Assistant.Drop
+import Assistant.Ssh
+import Assistant.TransferQueue
+import Assistant.Types.UrlRenderer
+import Assistant.Restart
+import qualified Annex.Branch
+import qualified Git
+import qualified Git.LsFiles
+import qualified Git.Command.Batch
+import qualified Git.Config
+import Utility.ThreadScheduler
+import qualified Assistant.Threads.Watcher as Watcher
+import Utility.Batch
+import Utility.NotificationBroadcaster
+import Config
+import Utility.HumanTime
+import Utility.Tense
+import Git.Repair
+import Git.Index
+import Assistant.Unused
+import Logs.Unused
+import Logs.Transfer
+import Config.Files
+import Types.Key (keyBackendName)
+import qualified Annex
+#ifdef WITH_WEBAPP
+import Assistant.WebApp.Types
+#endif
+#ifndef mingw32_HOST_OS
+import Utility.LogFile
+import Utility.DiskFree
+#endif
+
+import Data.Time.Clock.POSIX
+import qualified Data.Text as T
+
+{- This thread runs once at startup, and most other threads wait for it
+ - to finish. (However, the webapp thread does not, to prevent the UI
+ - being nonresponsive.) -}
+sanityCheckerStartupThread :: Maybe Duration -> NamedThread
+sanityCheckerStartupThread startupdelay = namedThreadUnchecked "SanityCheckerStartup" $ do
+	{- Stale git locks can prevent commits from happening, etc. -}
+	void $ repairStaleGitLocks =<< liftAnnex gitRepo
+
+	{- A corrupt index file can prevent the assistant from working at
+	 - all, so detect and repair. -}
+	ifM (not <$> liftAnnex (inRepo checkIndexFast))
+		( do
+			notice ["corrupt index file found at startup; removing and restaging"]
+			liftAnnex $ inRepo $ nukeFile . indexFile
+			{- Normally the startup scan avoids re-staging files,
+			 - but with the index deleted, everything needs to be
+			 - restaged. -}
+			modifyDaemonStatus_ $ \s -> s { forceRestage = True }
+		, whenM (liftAnnex $ inRepo missingIndex) $ do
+			debug ["no index file; restaging"]
+			modifyDaemonStatus_ $ \s -> s { forceRestage = True }
+		)
+	{- If the git-annex index file is corrupt, it's ok to remove it;
+	 - the data from the git-annex branch will be used, and the index
+	 - will be automatically regenerated. -}
+	unlessM (liftAnnex $ Annex.Branch.withIndex $ inRepo $ Git.Repair.checkIndexFast) $ do
+		notice ["corrupt annex/index file found at startup; removing"]
+		liftAnnex $ liftIO . nukeFile =<< fromRepo gitAnnexIndex
+
+	{- Fix up ssh remotes set up by past versions of the assistant. -}
+	liftIO $ fixUpSshRemotes
+
+	{- Clean up old temp files. -}
+	void $ liftAnnex $ tryNonAsync $ do
+		cleanOldTmpMisc
+		cleanReallyOldTmp
+
+	{- If there's a startup delay, it's done here. -}
+	liftIO $ maybe noop (threadDelaySeconds . Seconds . fromIntegral . durationSeconds) startupdelay
+
+	{- Notify other threads that the startup sanity check is done. -}
+	status <- getDaemonStatus
+	liftIO $ sendNotification $ startupSanityCheckNotifier status
+
+{- This thread wakes up hourly for inxepensive frequent sanity checks. -}
+sanityCheckerHourlyThread :: NamedThread
+sanityCheckerHourlyThread = namedThread "SanityCheckerHourly" $ forever $ do
+	liftIO $ threadDelaySeconds $ Seconds oneHour
+	hourlyCheck
+
+{- This thread wakes up daily to make sure the tree is in good shape. -}
+sanityCheckerDailyThread :: UrlRenderer -> NamedThread
+sanityCheckerDailyThread urlrenderer = namedThread "SanityCheckerDaily" $ forever $ do
+	waitForNextCheck
+
+	debug ["starting sanity check"]
+	void $ alertWhile sanityCheckAlert go
+	debug ["sanity check complete"]
+  where
+	go = do
+		modifyDaemonStatus_ $ \s -> s { sanityCheckRunning = True }
+
+		now <- liftIO getPOSIXTime -- before check started
+		r <- either showerr return 
+			=<< (tryIO . batch) <~> dailyCheck urlrenderer
+
+		modifyDaemonStatus_ $ \s -> s
+			{ sanityCheckRunning = False
+			, lastSanityCheck = Just now
+			}
+
+		return r
+
+	showerr e = do
+		liftAnnex $ warning $ show e
+		return False
+
+{- Only run one check per day, from the time of the last check. -}
+waitForNextCheck :: Assistant ()
+waitForNextCheck = do
+	v <- lastSanityCheck <$> getDaemonStatus
+	now <- liftIO getPOSIXTime
+	liftIO $ threadDelaySeconds $ Seconds $ calcdelay now v
+  where
+	calcdelay _ Nothing = oneDay
+	calcdelay now (Just lastcheck)
+		| lastcheck < now = max oneDay $
+			oneDay - truncate (now - lastcheck)
+		| otherwise = oneDay
+
+{- It's important to stay out of the Annex monad as much as possible while
+ - running potentially expensive parts of this check, since remaining in it
+ - will block the watcher. -}
+dailyCheck :: UrlRenderer -> Assistant Bool
+dailyCheck urlrenderer = do
+	checkRepoExists
+
+	g <- liftAnnex gitRepo
+	batchmaker <- liftIO getBatchCommandMaker
+
+	-- Find old unstaged symlinks, and add them to git.
+	(unstaged, cleanup) <- liftIO $ Git.LsFiles.notInRepo False ["."] g
+	now <- liftIO getPOSIXTime
+	forM_ unstaged $ \file -> do
+		ms <- liftIO $ catchMaybeIO $ getSymbolicLinkStatus file
+		case ms of
+			Just s	| toonew (statusChangeTime s) now -> noop
+				| isSymbolicLink s -> addsymlink file ms
+			_ -> noop
+	liftIO $ void cleanup
+
+	{- Allow git-gc to run once per day. More frequent gc is avoided
+	 - by default to avoid slowing things down. Only run repacks when 100x
+	 - the usual number of loose objects are present; we tend
+	 - to have a lot of small objects and they should not be a
+	 - significant size. -}
+	when (Git.Config.getMaybe "gc.auto" g == Just "0") $
+		liftIO $ void $ Git.Command.Batch.run batchmaker
+			[ Param "-c", Param "gc.auto=670000"
+			, Param "gc"
+			, Param "--auto"
+			] g
+
+	{- Check if the unused files found last time have been dealt with. -}
+	checkOldUnused urlrenderer
+
+	{- Run git-annex unused once per day. This is run as a separate
+	 - process to stay out of the annex monad and so it can run as a
+	 - batch job. -}
+	program <- liftIO readProgramFile
+	let (program', params') = batchmaker (program, [Param "unused"])
+	void $ liftIO $ boolSystem program' params'
+	{- Invalidate unused keys cache, and queue transfers of all unused
+	 - keys, or if no transfers are called for, drop them. -}
+	unused <- liftAnnex unusedKeys'
+	void $ liftAnnex $ setUnusedKeys unused
+	forM_ unused $ \k -> do
+		unlessM (queueTransfers "unused" Later k Nothing Upload) $
+			handleDrops "unused" True k Nothing Nothing
+
+	return True
+  where
+	toonew timestamp now = now < (realToFrac (timestamp + slop) :: POSIXTime)
+	slop = fromIntegral tenMinutes
+	insanity msg = do
+		liftAnnex $ warning msg
+		void $ addAlert $ sanityCheckFixAlert msg
+	addsymlink file s = do
+		isdirect <- liftAnnex isDirect
+		Watcher.runHandler (Watcher.onAddSymlink isdirect) file s
+		insanity $ "found unstaged symlink: " ++ file
+
+hourlyCheck :: Assistant ()
+hourlyCheck = do
+	checkRepoExists
+#ifndef mingw32_HOST_OS
+	checkLogSize 0
+#else
+	noop
+#endif
+
+#ifndef mingw32_HOST_OS
+{- Rotate logs once when total log file size is > 2 mb.
+ -
+ - If total log size is larger than the amount of free disk space,
+ - continue rotating logs until size is < 2 mb, even if this
+ - results in immediately losing the just logged data.
+ -}
+checkLogSize :: Int -> Assistant ()
+checkLogSize n = do
+	f <- liftAnnex $ fromRepo gitAnnexLogFile
+	logs <- liftIO $ listLogs f
+	totalsize <- liftIO $ sum <$> mapM getFileSize logs
+	when (totalsize > 2 * oneMegabyte) $ do
+		notice ["Rotated logs due to size:", show totalsize]
+		liftIO $ openLog f >>= handleToFd >>= redirLog
+		when (n < maxLogs + 1) $ do
+			df <- liftIO $ getDiskFree $ takeDirectory f
+			case df of
+				Just free
+					| free < fromIntegral totalsize ->
+						checkLogSize (n + 1)
+				_ -> noop
+  where
+	oneMegabyte :: Integer
+	oneMegabyte = 1000000
+#endif
+
+oneHour :: Int
+oneHour = 60 * 60
+
+oneDay :: Int
+oneDay = 24 * oneHour
+
+{- If annex.expireunused is set, find any keys that have lingered unused
+ - for the specified duration, and remove them.
+ -
+ - Otherwise, check to see if unused keys are piling up, and let the user
+ - know. -}
+checkOldUnused :: UrlRenderer -> Assistant ()
+checkOldUnused urlrenderer = go =<< annexExpireUnused <$> liftAnnex Annex.getGitConfig
+  where
+	go (Just Nothing) = noop
+	go (Just (Just expireunused)) = expireUnused (Just expireunused)
+	go Nothing = maybe noop prompt =<< describeUnusedWhenBig
+
+	prompt msg = 
+#ifdef WITH_WEBAPP
+		do
+			button <- mkAlertButton True (T.pack "Configure") urlrenderer ConfigUnusedR
+			void $ addAlert $ unusedFilesAlert [button] $ T.unpack $ renderTense Present msg
+#else
+		debug [show $ renderTense Past msg]
+#endif
+
+{- Files may be left in misctmp by eg, an interrupted add of files
+ - by the assistant, which hard links files to there as part of lockdown
+ - checks. Delete these files if they're more than a day old.
+ -
+ - Note that this is not safe to run after the Watcher starts up, since it
+ - will create such files, and due to hard linking they may have old
+ - mtimes. So, this should only be called from the
+ - sanityCheckerStartupThread, which runs before the Watcher starts up.
+ -
+ - Also, if a git-annex add is being run at the same time the assistant
+ - starts up, its tmp files could be deleted. However, the watcher will
+ - come along and add everything once it starts up anyway, so at worst
+ - this would make the git-annex add fail unexpectedly.
+ -}
+cleanOldTmpMisc :: Annex ()
+cleanOldTmpMisc = do
+	now <- liftIO getPOSIXTime
+	let oldenough = now - (60 * 60 * 24)
+	tmp <- fromRepo gitAnnexTmpMiscDir
+	liftIO $ mapM_ (cleanOld (<= oldenough)) =<< dirContentsRecursive tmp
+
+{- While .git/annex/tmp is now only used for storing partially transferred
+ - objects, older versions of git-annex used it for misctemp. Clean up any
+ - files that might be left from that, by looking for files whose names
+ - cannot be the key of an annexed object. Only delete files older than
+ - 1 week old.
+ -
+ - Also, some remotes such as rsync may use this temp directory for storing
+ - eg, encrypted objects that are being transferred. So, delete old
+ - objects that use a GPGHMAC backend.
+ -}
+cleanReallyOldTmp :: Annex ()
+cleanReallyOldTmp = do
+	now <- liftIO getPOSIXTime
+	let oldenough = now - (60 * 60 * 24 * 7)
+	tmp <- fromRepo gitAnnexTmpObjectDir
+	liftIO $ mapM_ (cleanjunk (<= oldenough)) =<< dirContentsRecursive tmp
+  where
+	cleanjunk check f = case fileKey (takeFileName f) of
+		Nothing -> cleanOld check f
+		Just k
+			| "GPGHMAC" `isPrefixOf` keyBackendName k ->
+				cleanOld check f
+			| otherwise -> noop
+
+cleanOld :: (POSIXTime -> Bool) -> FilePath -> IO ()
+cleanOld check f = go =<< catchMaybeIO getmtime
+  where
+	getmtime = realToFrac . modificationTime <$> getSymbolicLinkStatus f
+	go (Just mtime) | check mtime = nukeFile f
+	go _ = noop
+
+checkRepoExists :: Assistant ()
+checkRepoExists = do
+	g <- liftAnnex gitRepo
+	liftIO $ unlessM (doesDirectoryExist $ Git.repoPath g) $
+		terminateSelf

Assistant/Threads/TransferPoller.hs

@@ -0,0 +1,55 @@
+{- git-annex assistant transfer polling thread
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.Threads.TransferPoller where
+
+import Assistant.Common
+import Assistant.DaemonStatus
+import Logs.Transfer
+import Utility.NotificationBroadcaster
+import qualified Assistant.Threads.TransferWatcher as TransferWatcher
+
+import Control.Concurrent
+import qualified Data.Map as M
+
+{- This thread polls the status of ongoing transfers, determining how much
+ - of each transfer is complete. -}
+transferPollerThread :: NamedThread
+transferPollerThread = namedThread "TransferPoller" $ do
+	g <- liftAnnex gitRepo
+	tn <- liftIO . newNotificationHandle True =<<
+		transferNotifier <$> getDaemonStatus
+	forever $ do
+		liftIO $ threadDelay 500000 -- 0.5 seconds
+		ts <- currentTransfers <$> getDaemonStatus
+		if M.null ts
+			-- block until transfers running
+			then liftIO $ waitNotification tn
+			else mapM_ (poll g) $ M.toList ts
+  where
+	poll g (t, info)
+		{- Downloads are polled by checking the size of the
+		 - temp file being used for the transfer. -}
+		| transferDirection t == Download = do
+			let f = gitAnnexTmpObjectLocation (transferKey t) g
+			sz <- liftIO $ catchMaybeIO $ getFileSize f
+			newsize t info sz
+		{- Uploads don't need to be polled for when the TransferWatcher
+		 - thread can track file modifications. -}
+		| TransferWatcher.watchesTransferSize = noop
+		{- Otherwise, this code polls the upload progress
+		 - by reading the transfer info file. -}
+		| otherwise = do
+			let f = transferFile t g
+			mi <- liftIO $ catchDefaultIO Nothing $
+				readTransferInfoFile Nothing f
+			maybe noop (newsize t info . bytesComplete) mi
+
+	newsize t info sz
+		| bytesComplete info /= sz && isJust sz =
+			alterTransferInfo t $ \i -> i { bytesComplete = sz }
+		| otherwise = noop

Assistant/Threads/TransferScanner.hs

@@ -0,0 +1,182 @@
+{- git-annex assistant thread to scan remotes to find needed transfers
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.Threads.TransferScanner where
+
+import Assistant.Common
+import Assistant.Types.ScanRemotes
+import Assistant.ScanRemotes
+import Assistant.TransferQueue
+import Assistant.DaemonStatus
+import Assistant.Drop
+import Assistant.Sync
+import Assistant.DeleteRemote
+import Assistant.Types.UrlRenderer
+import Logs.Transfer
+import Logs.Location
+import Logs.Group
+import qualified Remote
+import qualified Types.Remote as Remote
+import Utility.ThreadScheduler
+import Utility.NotificationBroadcaster
+import Utility.Batch
+import qualified Git.LsFiles as LsFiles
+import qualified Backend
+import Annex.Content
+import Annex.Wanted
+import CmdLine.Action
+
+import qualified Data.Set as S
+
+{- This thread waits until a remote needs to be scanned, to find transfers
+ - that need to be made, to keep data in sync.
+ -}
+transferScannerThread :: UrlRenderer -> NamedThread
+transferScannerThread urlrenderer = namedThread "TransferScanner" $ do
+	startupScan
+	go S.empty
+  where
+	go scanned = do
+		scanrunning False
+		liftIO $ threadDelaySeconds (Seconds 2)
+		(rs, infos) <- unzip <$> getScanRemote
+		scanrunning True
+		if any fullScan infos || any (`S.notMember` scanned) rs
+			then do
+				expensiveScan urlrenderer rs
+				go $ scanned `S.union` S.fromList rs
+			else do
+				mapM_ failedTransferScan rs
+				go scanned
+	scanrunning b = do
+		ds <- modifyDaemonStatus $ \s -> 
+			(s { transferScanRunning = b }, s)
+		liftIO $ sendNotification $ transferNotifier ds
+		
+	{- All git remotes are synced, and all available remotes
+	 - are scanned in full on startup, for multiple reasons, including:
+	 -
+	 - * This may be the first run, and there may be remotes
+	 -   already in place, that need to be synced.
+	 - * Changes may have been made last time we run, but remotes were
+	 -   not available to be synced with.
+	 - * Changes may have been made to remotes while we were down.
+	 - * We may have run before, and scanned a remote, but
+	 -   only been in a subdirectory of the git remote, and so
+	 -   not synced it all.
+	 - * We may have run before, and had transfers queued,
+	 -   and then the system (or us) crashed, and that info was
+	 -   lost.
+	 - * A remote may be in the unwanted group, and this is a chance
+	 -   to determine if the remote has been emptied.
+	 -}
+	startupScan = do
+		reconnectRemotes True =<< syncGitRemotes <$> getDaemonStatus
+		addScanRemotes True =<< syncDataRemotes <$> getDaemonStatus
+
+{- This is a cheap scan for failed transfers involving a remote. -}
+failedTransferScan :: Remote -> Assistant ()
+failedTransferScan r = do
+	failed <- liftAnnex $ clearFailedTransfers (Remote.uuid r)
+	mapM_ retry failed
+  where
+	retry (t, info)
+		| transferDirection t == Download =
+			{- Check if the remote still has the key.
+			 - If not, relies on the expensiveScan to
+			 - get it queued from some other remote. -}
+			whenM (liftAnnex $ remoteHas r $ transferKey t) $
+				requeue t info
+		| otherwise =
+			{- The Transferrer checks when uploading
+			 - that the remote doesn't already have the
+			 - key, so it's not redundantly checked here. -}
+			requeue t info
+	requeue t info = queueTransferWhenSmall "retrying failed transfer" (associatedFile info) t r
+	
+{- This is a expensive scan through the full git work tree, finding
+ - files to transfer. The scan is blocked when the transfer queue gets
+ - too large. 
+ -
+ - This also finds files that are present either here or on a remote
+ - but that are not preferred content, and drops them. Searching for files
+ - to drop is done concurrently with the scan for transfers.
+ -
+ - TODO: It would be better to first drop as much as we can, before
+ - transferring much, to minimise disk use.
+ - 
+ - During the scan, we'll also check if any unwanted repositories are empty,
+ - and can be removed. While unrelated, this is a cheap place to do it,
+ - since we need to look at the locations of all keys anyway.
+ -}
+expensiveScan :: UrlRenderer -> [Remote] -> Assistant ()
+expensiveScan urlrenderer rs = batch <~> do
+	debug ["starting scan of", show visiblers]
+
+	let us = map Remote.uuid rs
+
+	mapM_ (liftAnnex . clearFailedTransfers) us
+
+	unwantedrs <- liftAnnex $ S.fromList
+		<$> filterM inUnwantedGroup us
+
+	g <- liftAnnex gitRepo
+	(files, cleanup) <- liftIO $ LsFiles.inRepo [] g
+	removablers <- scan unwantedrs files
+	void $ liftIO cleanup
+
+	debug ["finished scan of", show visiblers]
+
+	remove <- asIO1 $ removableRemote urlrenderer
+	liftIO $ mapM_ (void . tryNonAsync . remove) $ S.toList removablers
+  where
+	visiblers = let rs' = filter (not . Remote.readonly) rs
+		in if null rs' then rs else rs'
+
+	scan unwanted [] = return unwanted
+	scan unwanted (f:fs) = do
+		(unwanted', ts) <- maybe
+			(return (unwanted, []))
+			(findtransfers f unwanted)
+				=<< liftAnnex (Backend.lookupFile f)
+		mapM_ (enqueue f) ts
+		scan unwanted' fs
+
+	enqueue f (r, t) =
+		queueTransferWhenSmall "expensive scan found missing object"
+			(Just f) t r
+	findtransfers f unwanted key = do
+		{- The syncable remotes may have changed since this
+		 - scan began. -}
+		syncrs <- syncDataRemotes <$> getDaemonStatus
+		locs <- liftAnnex $ loggedLocations key
+		present <- liftAnnex $ inAnnex key
+		liftAnnex $ handleDropsFrom locs syncrs
+			"expensive scan found too many copies of object"
+			present key (Just f) Nothing callCommandAction
+		liftAnnex $ do
+			let slocs = S.fromList locs
+			let use a = return $ mapMaybe (a key slocs) syncrs
+			ts <- if present
+				then filterM (wantSend True (Just key) (Just f) . Remote.uuid . fst)
+					=<< use (genTransfer Upload False)
+				else ifM (wantGet True (Just key) (Just f))
+					( use (genTransfer Download True) , return [] )
+			let unwanted' = S.difference unwanted slocs
+			return (unwanted', ts)
+
+genTransfer :: Direction -> Bool -> Key -> S.Set UUID -> Remote -> Maybe (Remote, Transfer)
+genTransfer direction want key slocs r
+	| direction == Upload && Remote.readonly r = Nothing
+	| S.member (Remote.uuid r) slocs == want = Just
+		(r, Transfer direction (Remote.uuid r) key)
+	| otherwise = Nothing
+
+remoteHas :: Remote -> Key -> Annex Bool
+remoteHas r key = elem
+	<$> pure (Remote.uuid r)
+	<*> loggedLocations key

Assistant/Threads/TransferWatcher.hs

@@ -0,0 +1,104 @@
+{- git-annex assistant transfer watching thread
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.Threads.TransferWatcher where
+
+import Assistant.Common
+import Assistant.DaemonStatus
+import Assistant.TransferSlots
+import Logs.Transfer
+import Utility.DirWatcher
+import Utility.DirWatcher.Types
+import qualified Remote
+
+import Control.Concurrent
+import qualified Data.Map as M
+
+{- This thread watches for changes to the gitAnnexTransferDir,
+ - and updates the DaemonStatus's map of ongoing transfers. -}
+transferWatcherThread :: NamedThread
+transferWatcherThread = namedThread "TransferWatcher" $ do
+	dir <- liftAnnex $ gitAnnexTransferDir <$> gitRepo
+	liftIO $ createDirectoryIfMissing True dir
+	let hook a = Just <$> asIO2 (runHandler a)
+	addhook <- hook onAdd
+	delhook <- hook onDel
+	modifyhook <- hook onModify
+	errhook <- hook onErr
+	let hooks = mkWatchHooks
+		{ addHook = addhook
+		, delHook = delhook
+		, modifyHook = modifyhook
+		, errHook = errhook
+		}
+	void $ liftIO $ watchDir dir (const False) True hooks id
+	debug ["watching for transfers"]
+
+type Handler = FilePath -> Assistant ()
+
+{- Runs an action handler.
+ -
+ - Exceptions are ignored, otherwise a whole thread could be crashed.
+ -}
+runHandler :: Handler -> FilePath -> Maybe FileStatus -> Assistant ()
+runHandler handler file _filestatus =
+	either (liftIO . print) (const noop) =<< tryIO <~> handler file
+
+{- Called when there's an error with inotify. -}
+onErr :: Handler
+onErr = error
+
+{- Called when a new transfer information file is written. -}
+onAdd :: Handler
+onAdd file = case parseTransferFile file of
+	Nothing -> noop
+	Just t -> go t =<< liftAnnex (checkTransfer t)
+  where
+	go _ Nothing = noop -- transfer already finished
+	go t (Just info) = do
+		debug [ "transfer starting:", describeTransfer t info ]
+		r <- liftAnnex $ Remote.remoteFromUUID $ transferUUID t
+		updateTransferInfo t info { transferRemote = r }
+
+{- Called when a transfer information file is updated.
+ -
+ - The only thing that should change in the transfer info is the
+ - bytesComplete, so that's the only thing updated in the DaemonStatus. -}
+onModify :: Handler
+onModify file = case parseTransferFile file of
+	Nothing -> noop
+	Just t -> go t =<< liftIO (readTransferInfoFile Nothing file)
+  where
+	go _ Nothing = noop
+	go t (Just newinfo) = alterTransferInfo t $
+		\i -> i { bytesComplete = bytesComplete newinfo }
+
+{- This thread can only watch transfer sizes when the DirWatcher supports
+ - tracking modificatons to files. -}
+watchesTransferSize :: Bool
+watchesTransferSize = modifyTracked
+
+{- Called when a transfer information file is removed. -}
+onDel :: Handler
+onDel file = case parseTransferFile file of
+	Nothing -> noop
+	Just t -> do
+		debug [ "transfer finishing:", show t]
+		minfo <- removeTransfer t
+
+		-- Run transfer hook.
+		m <- transferHook <$> getDaemonStatus
+		maybe noop (\hook -> void $ liftIO $ forkIO $ hook t)
+			(M.lookup (transferKey t) m)
+
+		finished <- asIO2 finishedTransfer
+		void $ liftIO $ forkIO $ do
+			{- XXX race workaround delay. The location
+			 - log needs to be updated before finishedTransfer
+			 - runs. -}
+			threadDelay 10000000 -- 10 seconds
+			finished t minfo

Assistant/Threads/Transferrer.hs

@@ -0,0 +1,27 @@
+{- git-annex assistant data transferrer thread
+ -
+ - Copyright 2012 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+module Assistant.Threads.Transferrer where
+
+import Assistant.Common
+import Assistant.TransferQueue
+import Assistant.TransferSlots
+import Logs.Transfer
+import Config.Files
+import Utility.Batch
+
+{- Dispatches transfers from the queue. -}
+transfererThread :: NamedThread
+transfererThread = namedThread "Transferrer" $ do
+	program <- liftIO readProgramFile
+	batchmaker <- liftIO getBatchCommandMaker
+	forever $ inTransferSlot program batchmaker $
+		maybe (return Nothing) (uncurry genTransfer)
+			=<< getNextTransfer notrunning
+  where
+	{- Skip transfers that are already running. -}
+	notrunning = isNothing . startedTime

Assistant/Threads/UpgradeWatcher.hs

@@ -0,0 +1,110 @@
+{- git-annex assistant thread to detect when git-annex is upgraded
+ -
+ - Copyright 2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Assistant.Threads.UpgradeWatcher (
+	upgradeWatcherThread
+) where
+
+import Assistant.Common
+import Assistant.Upgrade
+import Utility.DirWatcher
+import Utility.DirWatcher.Types
+import Utility.ThreadScheduler
+import Assistant.Types.UrlRenderer
+import Assistant.Alert
+import Assistant.DaemonStatus
+#ifdef WITH_WEBAPP
+import Assistant.WebApp.Types
+import qualified Build.SysConfig
+#endif
+
+import Control.Concurrent.MVar
+import qualified Data.Text as T
+
+data WatcherState = InStartupScan | Started | Upgrading
+	deriving (Eq)
+
+upgradeWatcherThread :: UrlRenderer -> NamedThread
+upgradeWatcherThread urlrenderer = namedThread "UpgradeWatcher" $ do
+	whenM (liftIO checkSuccessfulUpgrade) $
+		showSuccessfulUpgrade urlrenderer
+	go =<< liftIO upgradeFlagFile
+  where
+	go Nothing = debug [ "cannot determine program path" ]
+	go (Just flagfile) = do
+		mvar <- liftIO $ newMVar InStartupScan
+		changed <- Just <$> asIO2 (changedFile urlrenderer mvar flagfile)
+		let hooks = mkWatchHooks
+			{ addHook = changed
+			, delHook = changed
+			, addSymlinkHook = changed
+			, modifyHook = changed
+			, delDirHook = changed
+			}
+		let dir = parentDir flagfile
+		let depth = length (splitPath dir) + 1
+		let nosubdirs f = length (splitPath f) == depth
+		void $ liftIO $ watchDir dir nosubdirs False hooks (startup mvar)
+	-- Ignore bogus events generated during the startup scan.
+	-- We ask the watcher to not generate them, but just to be safe..
+	startup mvar scanner = do
+		r <- scanner
+		void $ swapMVar mvar Started
+		return r
+
+changedFile :: UrlRenderer -> MVar WatcherState -> FilePath -> FilePath -> Maybe FileStatus -> Assistant ()
+changedFile urlrenderer mvar flagfile file _status
+	| flagfile /= file = noop
+	| otherwise = do
+		state <- liftIO $ readMVar mvar
+		when (state == Started) $ do
+			setstate Upgrading
+			ifM (liftIO upgradeSanityCheck)
+				( handleUpgrade urlrenderer
+				, do
+					debug ["new version failed sanity check; not using"]
+					setstate Started
+				)
+  where
+	setstate = void . liftIO . swapMVar mvar
+
+handleUpgrade :: UrlRenderer -> Assistant ()
+handleUpgrade urlrenderer = do
+	-- Wait 2 minutes for any final upgrade changes to settle.
+	-- (For example, other associated files may be being put into
+	-- place.) Not needed when using a distribution bundle, because
+	-- in that case git-annex handles the upgrade in a non-racy way.
+	liftIO $ unlessM usingDistribution $
+		threadDelaySeconds (Seconds 120)
+	ifM autoUpgradeEnabled
+		( do
+			debug ["starting automatic upgrade"]
+			unattendedUpgrade
+#ifdef WITH_WEBAPP
+		, do
+			button <- mkAlertButton True (T.pack "Finish Upgrade") urlrenderer ConfigFinishUpgradeR
+			void $ addAlert $ upgradeReadyAlert button
+#else
+		, noop
+#endif
+		)
+
+showSuccessfulUpgrade :: UrlRenderer -> Assistant ()
+showSuccessfulUpgrade urlrenderer = do
+#ifdef WITH_WEBAPP
+	button <- ifM autoUpgradeEnabled 
+		( pure Nothing
+		, Just <$> mkAlertButton True
+			(T.pack "Enable Automatic Upgrades")
+			urlrenderer ConfigEnableAutomaticUpgradeR
+		)
+	void $ addAlert $ upgradeFinishedAlert button Build.SysConfig.packageversion
+#else
+	noop
+#endif

Assistant/Threads/Upgrader.hs

@@ -0,0 +1,85 @@
+{- git-annex assistant thread to detect when upgrade is available
+ -
+ - Copyright 2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE CPP #-}
+
+module Assistant.Threads.Upgrader (
+	upgraderThread
+) where
+
+import Assistant.Common
+import Assistant.Upgrade
+
+import Assistant.Types.UrlRenderer
+import Assistant.DaemonStatus
+import Assistant.Alert
+import Utility.NotificationBroadcaster
+import qualified Annex
+import qualified Build.SysConfig
+import qualified Git.Version
+import Types.Distribution
+#ifdef WITH_WEBAPP
+import Assistant.WebApp.Types
+#endif
+
+import Data.Time.Clock
+import qualified Data.Text as T
+
+upgraderThread :: UrlRenderer -> NamedThread
+upgraderThread urlrenderer = namedThread "Upgrader" $
+	when (isJust Build.SysConfig.upgradelocation) $ do
+		{- Check for upgrade on startup, unless it was just
+		 - upgraded. -}
+		unlessM (liftIO checkSuccessfulUpgrade) $
+			checkUpgrade urlrenderer
+		h <- liftIO . newNotificationHandle False . networkConnectedNotifier =<< getDaemonStatus
+		go h =<< liftIO getCurrentTime
+  where
+	{- Wait for a network connection event. Then see if it's been
+	 - half a day since the last upgrade check. If so, proceed with
+	 - check. -}
+	go h lastchecked = do
+		liftIO $ waitNotification h
+		autoupgrade <- liftAnnex $ annexAutoUpgrade <$> Annex.getGitConfig
+		if autoupgrade == NoAutoUpgrade
+			then go h lastchecked
+			else do
+				now <- liftIO getCurrentTime
+				if diffUTCTime now lastchecked > halfday
+					then do
+						checkUpgrade urlrenderer
+						go h =<< liftIO getCurrentTime
+					else go h lastchecked
+	halfday = 12 * 60 * 60
+
+checkUpgrade :: UrlRenderer -> Assistant ()
+checkUpgrade urlrenderer = do
+	debug [ "Checking if an upgrade is available." ]
+	go =<< downloadDistributionInfo
+  where
+	go Nothing = debug [ "Failed to check if upgrade is available." ]
+	go (Just d) = do
+		let installed = Git.Version.normalize Build.SysConfig.packageversion
+		let avail = Git.Version.normalize $ distributionVersion d
+		let old = Git.Version.normalize <$> distributionUrgentUpgrade d
+		if Just installed <= old
+			then canUpgrade High urlrenderer d
+			else if installed < avail
+				then canUpgrade Low urlrenderer d
+				else debug [ "No new version found." ]
+
+canUpgrade :: AlertPriority -> UrlRenderer -> GitAnnexDistribution -> Assistant ()
+canUpgrade urgency urlrenderer d = ifM autoUpgradeEnabled
+	( startDistributionDownload d
+	, do
+#ifdef WITH_WEBAPP
+		button <- mkAlertButton True (T.pack "Upgrade") urlrenderer (ConfigStartUpgradeR d)
+		void $ addAlert (canUpgradeAlert urgency (distributionVersion d) button)
+#else
+		noop
+#endif
+	)

Assistant/Threads/Watcher.hs

@@ -0,0 +1,368 @@
+{- git-annex assistant tree watcher
+ -
+ - Copyright 2012-2013 Joey Hess <id@joeyh.name>
+ -
+ - Licensed under the GNU GPL version 3 or higher.
+ -}
+
+{-# LANGUAGE DeriveDataTypeable, CPP #-}
+
+module Assistant.Threads.Watcher (
+	watchThread,
+	WatcherControl(..),
+	checkCanWatch,
+	needLsof,
+	onAddSymlink,
+	runHandler,
+) where
+
+import Assistant.Common
+import Assistant.DaemonStatus
+import Assistant.Changes
+import Assistant.Types.Changes
+import Assistant.Alert
+import Utility.DirWatcher
+import Utility.DirWatcher.Types
+import qualified Annex
+import qualified Annex.Queue
+import qualified Git
+import qualified Git.UpdateIndex
+import qualified Git.LsFiles as LsFiles
+import qualified Backend
+import Annex.Direct
+import Annex.Content.Direct
+import Annex.CatFile
+import Annex.CheckIgnore
+import Annex.Link
+import Annex.FileMatcher
+import Types.FileMatcher
+import Annex.ReplaceFile
+import Git.Types
+import Config
+import Utility.ThreadScheduler
+#ifndef mingw32_HOST_OS
+import qualified Utility.Lsof as Lsof
+#endif
+
+import Data.Bits.Utils
+import Data.Typeable
+import qualified Data.ByteString.Lazy as L
+import qualified Control.Exception as E
+import Data.Time.Clock
+
+checkCanWatch :: Annex ()
+checkCanWatch
+	| canWatch = do
+#ifndef mingw32_HOST_OS
+		liftIO Lsof.setup
+		unlessM (liftIO (inPath "lsof") <||> Annex.getState Annex.force)
+			needLsof
+#else
+		noop
+#endif
+	| otherwise = error "watch mode is not available on this system"
+
+needLsof :: Annex ()
+needLsof = error $ unlines
+	[ "The lsof command is needed for watch mode to be safe, and is not in PATH."
+	, "To override lsof checks to ensure that files are not open for writing"
+	, "when added to the annex, you can use --force"
+	, "Be warned: This can corrupt data in the annex, and make fsck complain."
+	]
+
+{- A special exception that can be thrown to pause or resume the watcher. -}
+data WatcherControl = PauseWatcher | ResumeWatcher
+	deriving (Show, Eq, Typeable)
+
+instance E.Exception WatcherControl
+
+watchThread :: NamedThread
+watchThread = namedThread "Watcher" $
+	ifM (liftAnnex $ annexAutoCommit <$> Annex.getGitConfig)
+		( runWatcher
+		, waitFor ResumeWatcher runWatcher
+		)
+
+runWatcher :: Assistant ()
+runWatcher = do
+	startup <- asIO1 startupScan
+	matcher <- liftAnnex largeFilesMatcher
+	direct <- liftAnnex isDirect
+	symlinkssupported <- liftAnnex $ coreSymlinks <$> Annex.getGitConfig
+	addhook <- hook $ if direct
+		then onAddDirect symlinkssupported matcher
+		else onAdd matcher
+	delhook <- hook onDel
+	addsymlinkhook <- hook $ onAddSymlink direct
+	deldirhook <- hook onDelDir
+	errhook <- hook onErr
+	let hooks = mkWatchHooks
+		{ addHook = addhook
+		, delHook = delhook
+		, addSymlinkHook = addsymlinkhook
+		, delDirHook = deldirhook
+		, errHook = errhook
+		}
+	scanevents <- liftAnnex $ annexStartupScan <$> Annex.getGitConfig
+	h <- liftIO $ watchDir "." ignored scanevents hooks startup
+	debug [ "watching", "."]
+	
+	{- Let the DirWatcher thread run until signalled to pause it,
+	 - then wait for a resume signal, and restart. -}
+	waitFor PauseWatcher $ do
+		liftIO $ stopWatchDir h
+		waitFor ResumeWatcher runWatcher
+  where
+	hook a = Just <$> asIO2 (runHandler a)
+
+waitFor :: WatcherControl -> Assistant () -> Assistant ()
+waitFor sig next = do
+	r <- liftIO (E.try pause :: IO (Either E.SomeException ()))
+	case r of
+		Left e -> case E.fromException e of
+			Just s
+				| s == sig -> next
+			_ -> noop
+		_ -> noop
+  where
+	pause = runEvery (Seconds 86400) noop
+
+{- Initial scartup scan. The action should return once the scan is complete. -}
+startupScan :: IO a -> Assistant a
+startupScan scanner = do
+	liftAnnex $ showAction "scanning"
+	alertWhile' startupScanAlert $ do
+		r <- liftIO scanner
+
+		-- Notice any files that were deleted before
+		-- watching was started.
+		top <- liftAnnex $ fromRepo Git.repoPath
+		(fs, cleanup) <- liftAnnex $ inRepo $ LsFiles.deleted [top]
+		forM_ fs $ \f -> do
+			liftAnnex $ onDel' f
+			maybe noop recordChange =<< madeChange f RmChange
+		void $ liftIO cleanup
+		
+		liftAnnex $ showAction "started"
+		liftIO $ putStrLn ""
+		
+		modifyDaemonStatus_ $ \s -> s { scanComplete = True }
+
+		-- Ensure that the Committer sees any changes
+		-- that it did not process, and acts on them now that
+		-- the scan is complete.
+		refillChanges =<< getAnyChanges
+
+		return (True, r)
+
+{- Hardcoded ignores, passed to the DirWatcher so it can avoid looking
+ - at the entire .git directory. Does not include .gitignores. -}
+ignored :: FilePath -> Bool
+ignored = ig . takeFileName
+  where
+	ig ".git" = True
+	ig ".gitignore" = True
+	ig ".gitattributes" = True
+#ifdef darwin_HOST_OS
+	ig ".DS_Store" = True
+#endif
+	ig _ = False
+
+unlessIgnored :: FilePath -> Assistant (Maybe Change) -> Assistant (Maybe Change)
+unlessIgnored file a = ifM (liftAnnex $ checkIgnored file)
+	( noChange
+	, a
+	)
+
+type Handler = FilePath -> Maybe FileStatus -> Assistant (Maybe Change)
+
+{- Runs an action handler, and if there was a change, adds it to the ChangeChan.
+ -
+ - Exceptions are ignored, otherwise a whole watcher thread could be crashed.
+ -}
+runHandler :: Handler -> FilePath -> Maybe FileStatus -> Assistant ()
+runHandler handler file filestatus = void $ do
+	r <- tryIO <~> handler (normalize file) filestatus
+	case r of
+		Left e -> liftIO $ warningIO $ show e
+		Right Nothing -> noop
+		Right (Just change) -> do
+			-- Just in case the commit thread is not
+			-- flushing the queue fast enough.
+			liftAnnex Annex.Queue.flushWhenFull
+			recordChange change
+  where
+	normalize f
+		| "./" `isPrefixOf` file = drop 2 f
+		| otherwise = f
+
+{- Small files are added to git as-is, while large ones go into the annex. -}
+add :: FileMatcher Annex -> FilePath -> Assistant (Maybe Change)
+add bigfilematcher file = ifM (liftAnnex $ checkFileMatcher bigfilematcher file)
+	( pendingAddChange file
+	, do
+		liftAnnex $ Annex.Queue.addCommand "add"
+			[Params "--force --"] [file]
+		madeChange file AddFileChange
+	)
+
+onAdd :: FileMatcher Annex -> Handler
+onAdd matcher file filestatus
+	| maybe False isRegularFile filestatus =
+		unlessIgnored file $
+			add matcher file
+	| otherwise = noChange
+
+shouldRestage :: DaemonStatus -> Bool
+shouldRestage ds = scanComplete ds || forceRestage ds
+
+{- In direct mode, add events are received for both new files, and
+ - modified existing files.
+ -}
+onAddDirect :: Bool -> FileMatcher Annex -> Handler
+onAddDirect symlinkssupported matcher file fs = do
+	v <- liftAnnex $ catKeyFile file
+	case (v, fs) of
+		(Just key, Just filestatus) ->
+			ifM (liftAnnex $ sameFileStatus key file filestatus)
+				{- It's possible to get an add event for
+				 - an existing file that is not
+				 - really modified, but it might have
+				 - just been deleted and been put back,
+				 - so it symlink is restaged to make sure. -}
+				( ifM (shouldRestage <$> getDaemonStatus)
+					( do
+						link <- liftAnnex $ calcRepo $ gitAnnexLink file key
+						addLink file link (Just key)
+					, noChange
+					)
+				, guardSymlinkStandin (Just key) $ do
+					debug ["changed direct", file]
+					liftAnnex $ changedDirect key file
+					add matcher file
+				)
+		_ -> unlessIgnored file $
+			guardSymlinkStandin Nothing $ do
+				debug ["add direct", file]
+				add matcher file
+  where
+	{- On a filesystem without symlinks, we'll get changes for regular
+	 - files that git uses to stand-in for symlinks. Detect when
+	 - this happens, and stage the symlink, rather than annexing the
+	 - file. -}
+	guardSymlinkStandin mk a
+		| symlinkssupported = a
+		| otherwise = do
+			linktarget <- liftAnnex $ getAnnexLinkTarget file
+			case linktarget of
+				Nothing -> a
+				Just lt -> do
+					case fileKey $ takeFileName lt of
+						Nothing -> noop
+						Just key -> void $ liftAnnex $
+							addAssociatedFile key file
+					onAddSymlink' linktarget mk True file fs
+
+{- A symlink might be an arbitrary symlink, which is just added.
+ - Or, if it is a git-annex symlink, ensure it points to the content
+ - before adding it.
+ -}
+onAddSymlink :: Bool -> Handler
+onAddSymlink isdirect file filestatus = unlessIgnored file $ do
+	linktarget <- liftIO (catchMaybeIO $ readSymbolicLink file)
+	kv <- liftAnnex (Backend.lookupFile file)
+	onAddSymlink' linktarget kv isdirect file filestatus
+
+onAddSymlink' :: Maybe String -> Maybe Key -> Bool -> Handler
+onAddSymlink' linktarget mk isdirect file filestatus = go mk
+  where
+	go (Just key) = do
+		when isdirect $
+			liftAnnex $ void $ addAssociatedFile key file
+		link <- liftAnnex $ calcRepo $ gitAnnexLink file key
+		if linktarget == Just link
+			then ensurestaged (Just link) =<< getDaemonStatus
+			else do
+				unless isdirect $
+					liftAnnex $ replaceFile file $
+						makeAnnexLink link
+				addLink file link (Just key)
+	-- other symlink, not git-annex
+	go Nothing = ensurestaged linktarget =<< getDaemonStatus
+
+	{- This is often called on symlinks that are already
+	 - staged correctly. A symlink may have been deleted
+	 - and being re-added, or added when the watcher was
+	 - not running. So they're normally restaged to make sure.
+	 -
+	 - As an optimisation, during the startup scan, avoid
+	 - restaging everything. Only links that were created since
+	 - the last time the daemon was running are staged.
+	 - (If the daemon has never ran before, avoid staging
+	 - links too.)
+	 -}
+	ensurestaged (Just link) daemonstatus
+		| shouldRestage daemonstatus = addLink file link mk
+		| otherwise = case filestatus of
+			Just s
+				| not (afterLastDaemonRun (statusChangeTime s) daemonstatus) -> noChange
+			_ -> addLink file link mk
+	ensurestaged Nothing _ = noChange
+
+{- For speed, tries to reuse the existing blob for symlink target. -}
+addLink :: FilePath -> FilePath -> Maybe Key -> Assistant (Maybe Change)
+addLink file link mk = do
+	debug ["add symlink", file]
+	liftAnnex $ do
+		v <- catObjectDetails $ Ref $ ':':file
+		case v of
+			Just (currlink, sha, _type)
+				| s2w8 link == L.unpack currlink ->
+					stageSymlink file sha
+			_ -> stageSymlink file =<< hashSymlink link
+	madeChange file $ LinkChange mk
+
+onDel :: Handler
+onDel file _ = do
+	debug ["file deleted", file]
+	liftAnnex $ onDel' file
+	madeChange file RmChange
+
+onDel' :: FilePath -> Annex ()
+onDel' file = do
+	whenM isDirect $ do
+		mkey <- catKeyFile file
+		case mkey of
+			Nothing -> noop
+			Just key -> void $ removeAssociatedFile key file
+	Annex.Queue.addUpdateIndex =<<
+		inRepo (Git.UpdateIndex.unstageFile file)
+
+{- A directory has been deleted, or moved, so tell git to remove anything
+ - that was inside it from its cache. Since it could reappear at any time,
+ - use --cached to only delete it from the index.
+ -
+ - This queues up a lot of RmChanges, which assists the Committer in
+ - pairing up renamed files when the directory was renamed. -}
+onDelDir :: Handler
+onDelDir dir _ = do
+	debug ["directory deleted", dir]
+	(fs, clean) <- liftAnnex $ inRepo $ LsFiles.deleted [dir]
+
+	liftAnnex $ mapM_ onDel' fs
+
+	-- Get the events queued up as fast as possible, so the
+	-- committer sees them all in one block.
+	now <- liftIO getCurrentTime
+	recordChanges $ map (\f -> Change now f RmChange) fs
+
+	void $ liftIO clean
+	liftAnnex Annex.Queue.flushWhenFull
+	noChange
+
+{- Called when there's an error with inotify or kqueue. -}
+onErr :: Handler
+onErr msg _ = do
+	liftAnnex $ warning msg
+	void $ addAlert $ warningAlert "watcher" msg
+	noChange