convert to using Utility.Lockfile for transfer lock files

Should be no behavior changes, just simplified code.

The only actual difference is it doesn't truncate the lock file.
I think that was a holdover from when transfer info was written to the lock
file.

diff --git a/Annex/Transfer.hs b/Annex/Transfer.hs
index cf04810da18c8b8d840d0129ab50147a21f45151..1d7f2b98ff9a8099af21663a1c90951f7d5e9d72 100644 (file)
--- a/Annex/Transfer.hs
+++ b/Annex/Transfer.hs
@@ -23,9 +23,7 @@ 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
 
@@ -70,14 +68,14 @@ runTransfer' ignorelock t file shouldretry transferobserver transferaction = do
        info <- liftIO $ startTransferInfo file
        (meter, tfile, metervar) <- mkProgressUpdater t info
        mode <- annexFileMode
-       (fd, inprogress) <- liftIO $ prep tfile mode info
+       (lck, 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)
+                               (return lck)
                                (cleanup tfile)
                                (const $ transferaction meter)
                        transferobserver ok t info
@@ -85,25 +83,17 @@ runTransfer' ignorelock t file shouldretry transferobserver transferaction = do
   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)
+               let lck = transferLockFile tfile
+               r <- tryLockExclusive (Just mode) lck
+               case r of
+                       Nothing -> return (Nothing, True)
+                       Just lockhandle -> do
+                                       void $ tryIO $ writeTransferInfoFile info tfile
+                                       return (Just lockhandle, False)
 #else
        prep tfile _mode info = do
-               v <- catchMaybeIO $ lockExclusive (transferLockFile tfile)
+               let lck = transferLockFile tfile
+               v <- catchMaybeIO $ lockExclusive lck
                case v of
                        Nothing -> return (Nothing, False)
                        Just Nothing -> return (Nothing, True)
@@ -113,10 +103,11 @@ runTransfer' ignorelock t file shouldretry transferobserver transferaction = do
 #endif
        cleanup _ Nothing = noop
        cleanup tfile (Just lockhandle) = do
+               let lck = transferLockFile tfile
                void $ tryIO $ removeFile tfile
 #ifndef mingw32_HOST_OS
-               void $ tryIO $ removeFile $ transferLockFile tfile
-               closeFd lockhandle
+               void $ tryIO $ removeFile lck
+               dropLock lockhandle
 #else
                {- Windows cannot delete the lockfile until the lock
                 - is closed. So it's possible to race with another
@@ -124,7 +115,7 @@ runTransfer' ignorelock t file shouldretry transferobserver transferaction = do
                 - so ignore failure to remove.
                 -}
                dropLock lockhandle
-               void $ tryIO $ removeFile $ transferLockFile tfile
+               void $ tryIO $ removeFile lck
 #endif
        retry oldinfo metervar run = do
                v <- tryNonAsync run