add a configure check for StatFS

This way, the build log will indicate whether StatFS can be relied on.
I've tested all the failing architectures now, and on all of them,
the StatFS code now returns Nothing, rather than Just nonsense.

Also, if annex.diskreserve is set on a platform where StatFS is not
working, git-annex will complain.

Also, the Makefile was missing the sources target used when building with
cabal.

Annex/Content.hs

@@ -177,6 +177,7 @@ checkDiskSpace' adjustment key = do
 	r <- getConfig g "diskreserve" ""
 	let reserve = fromMaybe megabyte $ readSize dataUnits r
 	stats <- liftIO $ getFileSystemStats (gitAnnexDir g)
+	sanitycheck r stats
 	case (stats, keySize key) of
 		(Nothing, _) -> return ()
 		(_, Nothing) -> return ()
@@ -189,7 +190,17 @@ checkDiskSpace' adjustment key = do
 		needmorespace n = unlessM (Annex.getState Annex.force) $
 			error $ "not enough free space, need " ++ 
 				roughSize storageUnits True n ++
-				" more (use --force to override this check or adjust annex.diskreserve)"
+				" more" ++ forcemsg
+		forcemsg = " (use --force to override this check or adjust annex.diskreserve)"
+		sanitycheck r stats
+			| not (null r) && isNothing stats = do
+				unlessM (Annex.getState Annex.force) $
+					error $ "You have configured a diskreserve of "
+						++ r ++
+						" but disk space checking is not working"
+						++ forcemsg
+				return ()
+			| otherwise = return ()
 
 {- Moves a file into .git/annex/objects/
  -

Makefile

@@ -21,11 +21,13 @@ endif
 
 all: $(all)
 
+sources: $(sources)
+
 # Disables optimisation. Not for production use.
 fast: GHCFLAGS=-Wall $(IGNORE)
 fast: $(bins)
 
-Build/SysConfig.hs: configure.hs Build/TestConfig.hs
+Build/SysConfig.hs: configure.hs Build/TestConfig.hs Utility/StatFS.hs
 	$(GHCMAKE) configure
 	./configure
 

configure.hs

@@ -2,9 +2,11 @@
 
 import System.Directory
 import Data.List
+import Data.Maybe
 import System.Cmd.Utils
 
 import Build.TestConfig
+import Utility.StatFS
 
 tests :: [TestCase]
 tests =
@@ -21,6 +23,7 @@ tests =
 	, TestCase "wget" $ testCmd "wget" "wget --version >/dev/null"
 	, TestCase "bup" $ testCmd "bup" "bup --version >/dev/null"
 	, TestCase "gpg" $ testCmd "gpg" "gpg --version >/dev/null"
+	, TestCase "StatFS" testStatFS
 	] ++ shaTestCases [1, 256, 512, 224, 384]
 
 shaTestCases :: [Int] -> [TestCase]
@@ -63,6 +66,11 @@ getGitVersion = do
 	let version = last $ words $ head $ lines s
 	return $ Config "gitversion" (StringConfig version)
 
+testStatFS :: Test
+testStatFS = do
+	s <- getFileSystemStats "."
+	return $ Config "statfs_sane" $ BoolConfig $ isJust s
+
 {- Set up cabal file with version. -}
 cabalSetup :: IO ()
 cabalSetup = do

debian/changelog

@@ -1,6 +1,9 @@
 git-annex (3.20120114) UNRELEASED; urgency=low
 
-  * Add a sanity check for bad StatFS results.
+  * Add a sanity check for bad StatFS results. On architectures
+    where StatFS does not currently work (s390, mips, powerpc, sparc),
+    this disables the diskreserve checking code, and attempting to
+    configure an annex.diskreserve will result in an error.
 
  -- Joey Hess <joeyh@debian.org>  Sat, 14 Jan 2012 17:12:04 -0400
 

git-annex.cabal

@@ -1,5 +1,5 @@
 Name: git-annex
-Version: 3.20120113
+Version: 3.20120114
 Cabal-Version: >= 1.6
 License: GPL
 Maintainer: Joey Hess <joey@kitenet.net>