X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=rts%2Fposix%2FFileLock.c;h=cb36366070c7bbb54b5f9cc8d4891b782049279c;hb=b2bd63f99d643f6b3eb30bb72bb9ae26d4183252;hp=8d258202719dc50c75b1efcd7552688fe535ae33;hpb=7453eaaf0b690420ef2359f022a1838ad697b441;p=ghc-hetmet.git

diff --git a/rts/posix/FileLock.c b/rts/posix/FileLock.c
index 8d25820..cb36366 100644
--- a/rts/posix/FileLock.c
+++ b/rts/posix/FileLock.c
@@ -2,17 +2,20 @@
  *
  * (c) The GHC Team, 2007
  *
- * File locking support as required by Haskell 98
+ * File locking support as required by Haskell
  *
  * ---------------------------------------------------------------------------*/
  
+#include "PosixSource.h"
 #include "Rts.h"
-#include "Hash.h"
+
 #include "FileLock.h"
+#include "Hash.h"
 #include "RtsUtils.h"
 
-#include <unistd.h>
+#include <sys/types.h>
 #include <sys/stat.h>
+#include <unistd.h>
 #include <errno.h>
 
 typedef struct {
@@ -28,6 +31,10 @@ typedef struct {
 static HashTable *obj_hash;
 static HashTable *fd_hash;
 
+#ifdef THREADED_RTS
+static Mutex file_lock_mutex;
+#endif
+
 static int cmpLocks(StgWord w1, StgWord w2)
 {
     Lock *l1 = (Lock *)w1;
@@ -47,6 +54,9 @@ initFileLocking(void)
 {
     obj_hash = allocHashTable_(hashLock, cmpLocks);
     fd_hash  = allocHashTable(); /* ordinary word-based table */
+#ifdef THREADED_RTS
+    initMutex(&file_lock_mutex);
+#endif
 }
 
 static void
@@ -60,6 +70,9 @@ freeFileLocking(void)
 {
     freeHashTable(obj_hash, freeLock);
     freeHashTable(fd_hash,  NULL);
+#ifdef THREADED_RTS
+    closeMutex(&file_lock_mutex);
+#endif
 }
 
 int
@@ -67,6 +80,8 @@ lockFile(int fd, dev_t dev, ino_t ino, int for_writing)
 {
     Lock key, *lock;
 
+    ACQUIRE_LOCK(&file_lock_mutex);
+
     key.device = dev;
     key.inode  = ino;
 
@@ -80,16 +95,19 @@ lockFile(int fd, dev_t dev, ino_t ino, int for_writing)
         lock->readers = for_writing ? -1 : 1;
         insertHashTable(obj_hash, (StgWord)lock, (void *)lock);
         insertHashTable(fd_hash, fd, lock);
+        RELEASE_LOCK(&file_lock_mutex);
         return 0;
     }
     else
     {
         // single-writer/multi-reader locking:
         if (for_writing || lock->readers < 0) {
+            RELEASE_LOCK(&file_lock_mutex);
             return -1;
         }
         insertHashTable(fd_hash, fd, lock);
         lock->readers++;
+        RELEASE_LOCK(&file_lock_mutex);
         return 0;
     }
 }
@@ -99,11 +117,14 @@ unlockFile(int fd)
 {
     Lock *lock;
 
+    ACQUIRE_LOCK(&file_lock_mutex);
+
     lock = lookupHashTable(fd_hash, fd);
     if (lock == NULL) {
         // errorBelch("unlockFile: fd %d not found", fd); 
         // This is normal: we didn't know when calling unlockFile
         // whether this FD referred to a locked file or not.
+        RELEASE_LOCK(&file_lock_mutex);
         return 1;
     }
 
@@ -118,5 +139,7 @@ unlockFile(int fd)
         stgFree(lock);
     }
     removeHashTable(fd_hash, fd, NULL);
+
+    RELEASE_LOCK(&file_lock_mutex);
     return 0;
 }