From d35132810ae8d9c13d8b80004ab9c1a2544d671c Mon Sep 17 00:00:00 2001
From: Joey Hess <joey@kitenet.net>
Date: Sat, 4 May 2013 16:04:17 -0400
Subject: [PATCH] Got removable media mount detection working on Android.

Bionic has an amusing stub for `getmntent` that prints out
"FIX ME! implement getmntent()"

But, `/proc/mounts` is there, so I just parse it.
---
 Assistant/WebApp/Configurators/Local.hs |  4 ++++
 Assistant/WebApp/Configurators/Ssh.hs   |  6 ++---
 Utility/Mounts.hsc                      | 30 +++++++++++++++++++++++--
 Utility/libmounts.h                     |  2 +-
 doc/design/assistant/android.mdwn       |  4 +---
 5 files changed, 37 insertions(+), 9 deletions(-)

diff --git a/Assistant/WebApp/Configurators/Local.hs b/Assistant/WebApp/Configurators/Local.hs
index ea42793df7..cb366db8f2 100644
--- a/Assistant/WebApp/Configurators/Local.hs
+++ b/Assistant/WebApp/Configurators/Local.hs
@@ -300,6 +300,10 @@ driveList = mapM (gen . mnt_dir) =<< filter sane <$> getMounts
 		| dir == "/tmp" = False
 		| dir == "/run/shm" = False
 		| dir == "/run/lock" = False
+#ifdef __ANDROID__
+		| dir == "/mnt/sdcard" = False
+		| dir == "/sdcard" = False
+#endif
 		| otherwise = True
 #else
 driveList = return []
diff --git a/Assistant/WebApp/Configurators/Ssh.hs b/Assistant/WebApp/Configurators/Ssh.hs
index 2376ee548b..c3edbd3912 100644
--- a/Assistant/WebApp/Configurators/Ssh.hs
+++ b/Assistant/WebApp/Configurators/Ssh.hs
@@ -65,9 +65,9 @@ sshInputAForm hostnamefield def = SshInput
 	<*> aopt textField "Directory" (Just $ Just $ fromMaybe (T.pack gitAnnexAssistantDefaultDir) $ inputDirectory def)
 	<*> areq intField "Port" (Just $ inputPort def)
   where
+#ifndef __ANDROID__
 	check_hostname = checkM (liftIO . checkdns) hostnamefield
 	checkdns t = do
-#ifndef __ANDROID__
 		let h = T.unpack t
 		let canonname = Just $ defaultHints { addrFlags = [AI_CANONNAME] }
 		r <- catchMaybeIO $ getAddrInfo canonname (Just h) Nothing
@@ -79,8 +79,8 @@ sshInputAForm hostnamefield def = SshInput
 			Just [] -> Right t
 			Nothing -> Left bad_hostname
 #else
-		-- getAddrInfo currently broken on Android
-		return $ Right t
+	-- getAddrInfo currently broken on Android
+	check_hostname = hostnamefield -- unchecked
 #endif
 
 	check_username = checkBool (all (`notElem` "/:@ \t") . T.unpack)
diff --git a/Utility/Mounts.hsc b/Utility/Mounts.hsc
index c21a68032e..c13b0ece11 100644
--- a/Utility/Mounts.hsc
+++ b/Utility/Mounts.hsc
@@ -3,7 +3,7 @@
  - Derived from hsshellscript, originally written by
  - Volker Wysk <hsss@volker-wysk.de>
  - 
- - Modified to support BSD and Mac OS X by
+ - Modified to support BSD, Mac OS X, and Android by
  - Joey Hess <joey@kitenet.net>
  -
  - Licensed under the GNU LGPL version 2.1 or higher.
@@ -16,13 +16,18 @@ module Utility.Mounts (
 	getMounts
 ) where
 
+#ifndef __ANDROID__
 import Control.Monad
 import Foreign
 import Foreign.C
 import GHC.IO hiding (finally, bracket)
 import Prelude hiding (catch)
-
 #include "libmounts.h"
+#else
+import Utility.Exception
+import Data.Maybe
+import Control.Applicative
+#endif
 
 {- This is a stripped down mntent, containing only
  - fields available everywhere. -}
@@ -32,6 +37,8 @@ data Mntent = Mntent
 	, mnt_type :: String
 	} deriving (Read, Show, Eq, Ord)
 
+#ifndef __ANDROID__
+
 getMounts :: IO [Mntent]
 getMounts = do
 	h <- c_mounts_start
@@ -67,3 +74,22 @@ foreign import ccall unsafe "libmounts.h mounts_next" c_mounts_next
         :: Ptr () -> IO (Ptr ())
 foreign import ccall unsafe "libmounts.h mounts_end" c_mounts_end
         :: Ptr () -> IO CInt
+
+#else
+
+{- Android does not support getmntent (well, it's a no-op stub in Bionic).
+ - 
+ - But, the linux kernel's /proc/mounts is available to be parsed.
+ -}
+getMounts :: IO [Mntent]
+getMounts = catchDefaultIO [] $
+	mapMaybe (parse . words) . lines <$> readFile "/proc/mounts"
+  where
+  	parse (device:mountpoint:fstype:_rest) = Just $ Mntent
+		{ mnt_fsname = device
+		, mnt_dir = mountpoint
+		, mnt_type = fstype
+		}
+	parse _ = Nothing
+
+#endif
diff --git a/Utility/libmounts.h b/Utility/libmounts.h
index 460fcc7abd..24df55f310 100644
--- a/Utility/libmounts.h
+++ b/Utility/libmounts.h
@@ -6,7 +6,7 @@
 # define GETMNTINFO
 #else
 #if defined __ANDROID__
-# warning mounts listing code not available for Android
+/* Android is handled by the Haskell code, not here. */
 # define UNKNOWN
 #else
 #if defined (__linux__) || defined (__FreeBSD_kernel__)
diff --git a/doc/design/assistant/android.mdwn b/doc/design/assistant/android.mdwn
index 2a2609341d..4b1a468e58 100644
--- a/doc/design/assistant/android.mdwn
+++ b/doc/design/assistant/android.mdwn
@@ -28,8 +28,6 @@
 * Ssh server and Rsync.net configuration stops where ssh
   should be prompting for a password in the terminal.
 * Enabling debug logging in the webapp doesn't seem to work.
-* S3, glacier, and local pairing are not yet enabled for Android.
+* glacier and local pairing are not yet enabled for Android.
 * The "Files" link doesn't start a file browser. Should be possible to do
   on Android via intents, I suppose?
-* Does not detect mounted USB drives. getMounts is failing
-  probably?