can now build Android targeted binary

Various things that don't work on Android are just ifdefed out.

* the webapp (needs template haskell for arm)
* --include and --exclude globbing (needs libpcre, which is not ported;
  probably I'll make it use the pure haskell glob library instead)
* annex.diskreserve checking (missing sys/statvfs.h)
* timestamp preservation support (yawn)
* S3
* WebDAV
* XMPP

The resulting 17mb binary has been tested on Android, and it is able to,
at least, print its usage message.

7 files changed, 64 insertions, 6 deletions

diff --git a/Assistant/Pairing.hs b/Assistant/Pairing.hs
index 6df54873a..2c1fcf0d0 100644
--- a/Assistant/Pairing.hs
+++ b/Assistant/Pairing.hs
@@ -5,6 +5,8 @@
  - Licensed under the GNU GPL version 3 or higher.
  -}
 
+{-# LANGUAGE CPP #-}
+
 module Assistant.Pairing where
 
 import Common.Annex
@@ -70,7 +72,12 @@ data PairingInProgress = PairingInProgress
 	}
 	deriving (Show)
 
-data SomeAddr = IPv4Addr HostAddress | IPv6Addr HostAddress6
+data SomeAddr = IPv4Addr HostAddress
+{- My Android build of the Network library does not currently have IPV6
+ - support. -}
+#ifndef WITH_ANDROID
+	| IPv6Addr HostAddress6
+#endif
 	deriving (Ord, Eq, Read, Show)
 
 {- This contains the whole secret, just lightly obfuscated to make it not
diff --git a/Command/Add.hs b/Command/Add.hs
index a68b190de..bfab33099 100644
--- a/Command/Add.hs
+++ b/Command/Add.hs
@@ -5,6 +5,8 @@
  - Licensed under the GNU GPL version 3 or higher.
  -}
 
+{-# LANGUAGE CPP #-}
+
 module Command.Add where
 
 import Common.Annex
@@ -18,7 +20,9 @@ import Logs.Location
 import Annex.Content
 import Annex.Content.Direct
 import Annex.Perms
+#ifndef WITH_ANDROID
 import Utility.Touch
+#endif
 import Utility.FileMode
 import Config
 import qualified Git.HashObject
@@ -141,12 +145,14 @@ link file key hascontent = handle (undo file key) $ do
 	l <- calcGitLink file key
 	liftIO $ createSymbolicLink l file
 
+#ifndef WITH_ANDROID
 	when hascontent $ do
 		-- touch the symlink to have the same mtime as the
 		-- file it points to
 		liftIO $ do
 			mtime <- modificationTime <$> getFileStatus file
 			touch file (TimeSpec mtime) False
+#endif
 
 	return l
 
diff --git a/Limit.hs b/Limit.hs
index 80608bcc6..85cce4f44 100644
--- a/Limit.hs
+++ b/Limit.hs
@@ -5,13 +5,17 @@
  - Licensed under the GNU GPL version 3 or higher.
  -}
 
+{-# LANGUAGE CPP #-}
+
 module Limit where
 
-import Text.Regex.PCRE.Light.Char8
-import System.Path.WildMatch
 import Data.Time.Clock.POSIX
 import qualified Data.Set as S
 import qualified Data.Map as M
+#ifndef WITH_ANDROID
+import Text.Regex.PCRE.Light.Char8
+import System.Path.WildMatch
+#endif
 
 import Common.Annex
 import qualified Annex
@@ -81,11 +85,15 @@ limitExclude :: MkLimit
 limitExclude glob = Right $ const $ return . not . matchglob glob
 
 matchglob :: String -> Annex.FileInfo -> Bool
+#ifdef WITH_ANDROID
+matchglob _ _ = error "glob matching not supported"
+#else
 matchglob glob (Annex.FileInfo { Annex.matchFile = f }) =
 	isJust $ match cregex f []
   where
 	cregex = compile regex []
 	regex = '^':wildToRegex glob
+#endif
 
 {- Adds a limit to skip files not believed to be present
  - in a specfied repository. -}
diff --git a/Makefile b/Makefile
index 83fa33d47..841f52150 100644
--- a/Makefile
+++ b/Makefile
@@ -14,6 +14,12 @@ sources=Build/SysConfig.hs Utility/Touch.hs Utility/Mounts.hs
 all=$(bins) $(mans) docs
 
 OS:=$(shell uname | sed 's/[-_].*//')
+ifeq ($(ANDROID),1)
+OPTFLAGS?=-DWITH_INOTIFY -DWITH_ANDROID
+clibs=Utility/libdiskfree.o Utility/libmounts.o
+CFLAGS:=-Wall -DWITH_ANDROID
+THREADFLAGS=-threaded
+else
 ifeq ($(OS),Linux)
 OPTFLAGS?=-DWITH_INOTIFY -DWITH_DBUS
 clibs=Utility/libdiskfree.o Utility/libmounts.o
@@ -41,6 +47,7 @@ clibs=Utility/libdiskfree.o Utility/libmounts.o Utility/libkqueue.o
 endif
 endif
 endif
+endif
 
 ALLFLAGS = $(BASEFLAGS) $(FEATURES) $(OPTFLAGS) $(THREADFLAGS)
 
@@ -51,7 +58,8 @@ ifdef PROFILE
 GHCFLAGS=-prof -auto-all -rtsopts -caf-all -fforce-recomp $(ALLFLAGS)
 endif
 
-GHCMAKE=ghc $(GHCFLAGS) --make
+GHC?=ghc
+GHCMAKE=$(GHC) $(GHCFLAGS) --make
 
 # Am I typing :make in vim? Do a fast build.
 ifdef VIM
@@ -113,7 +121,7 @@ test: $(sources) $(clibs)
 
 testcoverage:
 	rm -f test.tix test
-	ghc $(GHCFLAGS) -outputdir $(GIT_ANNEX_TMP_BUILD_DIR)/testcoverage --make -fhpc test
+	$(GHC) $(GHCFLAGS) -outputdir $(GIT_ANNEX_TMP_BUILD_DIR)/testcoverage --make -fhpc test
 	./test
 	@echo ""
 	@hpc report test --exclude=Main --exclude=QC
@@ -216,6 +224,19 @@ osxapp:
 	rm -f tmp/git-annex.dmg.bz2
 	bzip2 --fast tmp/git-annex.dmg
 
+# Cross compile for Android binary.
+# Uses https://github.com/neurocyte/ghc-android
+#
+# configure is run, probing the local system.
+# So the Android should have all the same stuff that configure probes for,
+# including the same version of git.
+android:
+	$(MAKE) Build/SysConfig.hs
+	GHC=$$HOME/.ghc-android-14-arm-linux-androideabi-4.7/bin/arm-unknown-linux-androideabi-ghc \
+	CC=$$HOME/.ghc-android-14-arm-linux-androideabi-4.7/bin/arm-linux-androideabi-gcc \
+	FEATURES="-DWITH_ANDROID -DWITH_ASSISTANT -DWITH_DNS" \
+	ANDROID=1 $(MAKE) fast
+
 # used by ./ghci
 getflags:
 	@echo $(ALLFLAGS) $(clibs)
diff --git a/Utility/ThreadScheduler.hs b/Utility/ThreadScheduler.hs
index 96bccbe70..fdf40ab6d 100644
--- a/Utility/ThreadScheduler.hs
+++ b/Utility/ThreadScheduler.hs
@@ -6,13 +6,17 @@
  - Licensed under the GNU GPL version 3 or higher.
  -}
 
+{-# LANGUAGE CPP #-}
+
 module Utility.ThreadScheduler where
 
 import Common
 
 import Control.Concurrent
-import System.Posix.Terminal
 import System.Posix.Signals
+#ifndef WITH_ANDROID
+import System.Posix.Terminal
+#endif
 
 newtype Seconds = Seconds { fromSeconds :: Int }
 	deriving (Eq, Ord, Show)
@@ -49,8 +53,10 @@ waitForTermination :: IO ()
 waitForTermination = do
 	lock <- newEmptyMVar
 	check softwareTermination lock
+#ifndef WITH_ANDROID
 	whenM (queryTerminal stdInput) $
 		check keyboardSignal lock
+#endif
 	takeMVar lock
   where
 	check sig lock = void $
diff --git a/Utility/libdiskfree.c b/Utility/libdiskfree.c
index 5e84d4bde..a9ca90b41 100644
--- a/Utility/libdiskfree.c
+++ b/Utility/libdiskfree.c
@@ -22,6 +22,10 @@
 # define STATCALL statfs /* statfs64 not yet tested on a real FreeBSD machine */
 # define STATSTRUCT statfs
 #else
+#if defined WITH_ANDROID
+# warning free space checking code not available for Android
+# define UNKNOWN
+#else
 #if defined (__linux__) || defined (__FreeBSD_kernel__)
 /* Linux or Debian kFreeBSD */
 /* This is a POSIX standard, so might also work elsewhere too. */
@@ -34,6 +38,7 @@
 #endif
 #endif
 #endif
+#endif
 
 #include <errno.h>
 #include <stdio.h>
diff --git a/Utility/libmounts.h b/Utility/libmounts.h
index b65978629..76b2484d3 100644
--- a/Utility/libmounts.h
+++ b/Utility/libmounts.h
@@ -5,6 +5,10 @@
 # include <sys/mount.h>
 # define GETMNTINFO
 #else
+#if defined WITH_ANDROID
+# warning mounts listing code not available for Android
+# define UNKNOWN
+#else
 #if defined (__linux__) || defined (__FreeBSD_kernel__)
 /* Linux or Debian kFreeBSD */
 #include <mntent.h>
@@ -14,6 +18,7 @@
 # define UNKNOWN
 #endif
 #endif
+#endif
 
 #include <stdio.h>