Rsync will now be used to resume interrupted/failed partial file transfers from a remote.

Remotes.hs

@@ -36,6 +36,7 @@ import Utility
 import qualified Core
 import Messages
 import CopyFile
+import qualified SysConfig
 
 {- Human visible list of remotes. -}
 list :: [Git.Repo] -> String
@@ -199,9 +200,13 @@ copyFromRemote r key file
 	| Git.repoIsSsh r = getssh
 	| otherwise = error "copying from non-ssh repo not supported"
 	where
-		getlocal = liftIO $ copyFile keyloc file
-		getssh = scp r [sshLocation r keyloc, file]
 		keyloc = annexLocation r key
+		getlocal = liftIO $ copyFile keyloc file
+		getssh = do
+			exists <- liftIO $ doesFileExist file
+			if exists && SysConfig.rsync
+				then rsync r [sshLocation r keyloc, file]
+				else scp r [sshLocation r keyloc, file]
 
 {- Tries to copy a key's content to a file on a remote. -}
 copyToRemote :: Git.Repo -> Key -> FilePath -> Annex Bool
@@ -224,9 +229,18 @@ sshLocation r file = Git.urlHost r ++ ":" ++ shellEscape file
 scp :: Git.Repo -> [String] -> Annex Bool
 scp r params = do
 	scpoptions <- repoConfig r "scp-options" ""
-	showProgress -- make way for scp progress bar
+	showProgress -- make way for progress bar
 	liftIO $ boolSystem "scp" $ "-p":(words scpoptions) ++ params
 
+{- Runs rsync against a specified remote, resuming any interrupted file
+ - transfer. (Honors annex-rsync-options.) -}
+rsync :: Git.Repo -> [String] -> Annex Bool
+rsync r params = do
+	rsyncoptions <- repoConfig r "rsync-options" ""
+	showProgress -- make way for progress bar
+	liftIO $ boolSystem "rsync" $ ["--progress", "-a", "--inplace"] ++
+		words rsyncoptions ++ params
+
 {- Runs a command in a remote, using ssh if necessary.
  - (Honors annex-ssh-options.) -}
 runCmd :: Git.Repo -> String -> [String] -> Annex Bool

configure.hs

@@ -20,8 +20,9 @@ tests = [
 	  TestCase "cp -a" "cp_a" $ testCp "-a"
 	, TestCase "cp -p" "cp_p" $ testCp "-p"
 	, TestCase "cp --reflink=auto" "cp_reflink_auto" $ testCp "--reflink=auto"
-	, TestCase "uuid" "uuid" $ requireCommand "uuid" "uuid"
+	, TestCase "uuid" "uuid" $ requireCmd "uuid" "uuid"
-	, TestCase "xargs -0" "xargs_0" $ requireCommand "xargs -0" "xargs -0 </dev/null"
+	, TestCase "xargs -0" "xargs_0" $ requireCmd "xargs -0" "xargs -0 </dev/null"
+	, TestCase "rsync" "rsync" $ testCmd "rsync --version >/dev/null"
 	]
 
 tmpDir :: String
@@ -33,14 +34,14 @@ testFile = tmpDir ++ "/testfile"
 quiet :: String -> String
 quiet s = s ++ " >/dev/null 2>&1"
 
-requireCommand :: String -> String -> Test
+requireCmd :: String -> String -> Test
-requireCommand command cmdline = do
+requireCmd c cmdline = do
 	ret <- testCmd $ quiet cmdline
 	if ret
 		then return True
 		else do
 			testEnd False
-			error $ "** the " ++ command ++ " command is required to use git-annex"
+			error $ "** the " ++ c ++ " command is required to use git-annex"
 
 testCp :: String -> Test
 testCp option = testCmd $ quiet $ "cp " ++ option ++ " " ++ testFile ++ 

debian/changelog

@@ -1,3 +1,10 @@
+git-annex (0.11) UNRELEASED; urgency=low
+
+  * Rsync will now be used to resume interrupted/failed partial file
+    transfers from a remote.
+
+ -- Joey Hess <joeyh@debian.org>  Thu, 02 Dec 2010 16:54:12 -0400
+
 git-annex (0.10) unstable; urgency=low
 
   * In .gitattributes, the annex.numcopies attribute can be used

debian/control

@@ -1,7 +1,7 @@
 Source: git-annex
 Section: utils
 Priority: optional
-Build-Depends: debhelper (>= 7.0.50), ghc6, libghc6-missingh-dev, libghc6-testpack-dev, ikiwiki, uuid
+Build-Depends: debhelper (>= 7.0.50), ghc6, libghc6-missingh-dev, libghc6-testpack-dev, ikiwiki, uuid, rsync
 Maintainer: Joey Hess <joeyh@debian.org>
 Standards-Version: 3.9.1
 Vcs-Git: git://git.kitenet.net/git-annex
@@ -10,7 +10,7 @@ Homepage: http://git-annex.branchable.com/
 Package: git-annex
 Architecture: any
 Section: utils
-Depends: ${misc:Depends}, ${shlibs:Depends}, git | git-core, uuid, openssh-client
+Depends: ${misc:Depends}, ${shlibs:Depends}, git | git-core, uuid, openssh-client, rsync
 Description: manage files with git, without checking their contents into git
  git-annex allows managing files with git, without checking the file
  contents into git. While that may seem paradoxical, it is useful when

doc/install.mdwn

@@ -5,6 +5,7 @@ To build and use git-annex, you will need:
 * MissingH: <http://github.com/jgoerzen/missingh/wiki>
 * `uuid`: <http://www.ossp.org/pkg/lib/uuid/>
 * `xargs`: <http://savannah.gnu.org/projects/findutils/>
+* `rsync` (optional but recommended)
 * Then just [[download]] git-annex and run: `make; make install`
 
 ([Ikiwiki](http://ikiwiki.info) is needed to build the documentation,

doc/todo/rsync.mdwn

@@ -1,2 +1,4 @@
 Transferring a file from a ssh:// remote should use rsync to allow resuming
 of a prior transfer.
+
+[[done]]