X-Git-Url: http://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Ftdb2%2Flock.c;h=76b8bc3157977462fbebc3983caad5dbb366ed5c;hp=4033d0afe813e59bf4dee4b8bcc9e5d34757c298;hb=c2d60644d2c00fb32258b380bb25ce0a26b87026;hpb=dc9da1e34fe6a9d113fd57e116ebbc6d5bd54819

diff --git a/ccan/tdb2/lock.c b/ccan/tdb2/lock.c
index 4033d0af..76b8bc31 100644
--- a/ccan/tdb2/lock.c
+++ b/ccan/tdb2/lock.c
@@ -37,7 +37,7 @@ static enum TDB_ERROR owner_conflict(struct tdb_context *tdb, const char *call)
 			  call);
 }
 
-/* If we fork, we no longer really own locks: preserves errno */
+/* If we fork, we no longer really own locks. */
 static bool check_lock_pid(struct tdb_context *tdb,
 			   const char *call, bool log)
 {
@@ -99,16 +99,21 @@ int tdb_fcntl_unlock(int fd, int rw, off_t off, off_t len, void *unused)
 static int lock(struct tdb_context *tdb,
 		      int rw, off_t off, off_t len, bool waitflag)
 {
+	int ret;
 	if (tdb->file->allrecord_lock.count == 0
 	    && tdb->file->num_lockrecs == 0) {
 		tdb->file->locker = getpid();
 	}
 
 	tdb->stats.lock_lowlevel++;
-	if (!waitflag)
+	ret = tdb->lock_fn(tdb->file->fd, rw, off, len, waitflag,
+			   tdb->lock_data);
+	if (!waitflag) {
 		tdb->stats.lock_nonblock++;
-	return tdb->lock_fn(tdb->file->fd, rw, off, len, waitflag,
-			    tdb->lock_data);
+		if (ret != 0)
+			tdb->stats.lock_nonblock_fail++;
+	}
+	return ret;
 }
 
 static int unlock(struct tdb_context *tdb, int rw, off_t off, off_t len)
@@ -224,16 +229,14 @@ static enum TDB_ERROR tdb_brlock(struct tdb_context *tdb,
 static enum TDB_ERROR tdb_brunlock(struct tdb_context *tdb,
 				   int rw_type, tdb_off_t offset, size_t len)
 {
-	int ret;
-
 	if (tdb->flags & TDB_NOLOCK) {
 		return TDB_SUCCESS;
 	}
 
-	ret = unlock(tdb, rw_type, offset, len);
+	if (!check_lock_pid(tdb, "tdb_brunlock", true))
+		return TDB_ERR_LOCK;
 
-	/* If we fail, *then* we verify that we owned the lock.  If not, ok. */
-	if (ret == -1 && check_lock_pid(tdb, "tdb_brunlock", false)) {
+	if (unlock(tdb, rw_type, offset, len) == -1) {
 		return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
 				  "tdb_brunlock failed (fd=%d) at offset %zu"
 				  " rw_type=%d len=%zu: %s",
@@ -325,13 +328,13 @@ enum TDB_ERROR tdb_lock_and_recover(struct tdb_context *tdb)
 		return ecode;
 	}
 
-	ecode = tdb_lock_open(tdb, TDB_LOCK_WAIT|TDB_LOCK_NOCHECK);
+	ecode = tdb_lock_open(tdb, F_WRLCK, TDB_LOCK_WAIT|TDB_LOCK_NOCHECK);
 	if (ecode != TDB_SUCCESS) {
 		tdb_allrecord_unlock(tdb, F_WRLCK);
 		return ecode;
 	}
 	ecode = tdb_transaction_recover(tdb);
-	tdb_unlock_open(tdb);
+	tdb_unlock_open(tdb, F_WRLCK);
 	tdb_allrecord_unlock(tdb, F_WRLCK);
 
 	return ecode;
@@ -612,14 +615,15 @@ again:
 	goto again;
 }
 
-enum TDB_ERROR tdb_lock_open(struct tdb_context *tdb, enum tdb_lock_flags flags)
+enum TDB_ERROR tdb_lock_open(struct tdb_context *tdb,
+			     int ltype, enum tdb_lock_flags flags)
 {
-	return tdb_nest_lock(tdb, TDB_OPEN_LOCK, F_WRLCK, flags);
+	return tdb_nest_lock(tdb, TDB_OPEN_LOCK, ltype, flags);
 }
 
-void tdb_unlock_open(struct tdb_context *tdb)
+void tdb_unlock_open(struct tdb_context *tdb, int ltype)
 {
-	tdb_nest_unlock(tdb, TDB_OPEN_LOCK, F_WRLCK);
+	tdb_nest_unlock(tdb, TDB_OPEN_LOCK, ltype);
 }
 
 bool tdb_has_open_lock(struct tdb_context *tdb)
@@ -851,6 +855,10 @@ void tdb_lock_cleanup(struct tdb_context *tdb)
 {
 	unsigned int i;
 
+	/* We don't want to warn: they're allowed to close tdb after fork. */
+	if (!check_lock_pid(tdb, "tdb_close", false))
+		return;
+
 	while (tdb->file->allrecord_lock.count
 	       && tdb->file->allrecord_lock.owner == tdb) {
 		tdb_allrecord_unlock(tdb, tdb->file->allrecord_lock.ltype);