X-Git-Url: http://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Ftdb%2Flock.c;h=07545b345ba0c6d80af5ed541376eca195afb87b;hp=f156c0fa7b2e548640d47db23df71c9427ec73ce;hb=67aef98e2e4409b69ba668a2a4a9f0757ddc7ca7;hpb=7104b7bc2e7f9829891477dbb04a9df926a656a7

diff --git a/ccan/tdb/lock.c b/ccan/tdb/lock.c
index f156c0fa..07545b34 100644
--- a/ccan/tdb/lock.c
+++ b/ccan/tdb/lock.c
@@ -84,7 +84,7 @@ int tdb_brlock(struct tdb_context *tdb, tdb_off_t offset,
 			TDB_LOG((tdb, TDB_DEBUG_TRACE,"tdb_brlock failed (fd=%d) at offset %d rw_type=%d lck_type=%d len=%d\n", 
 				 tdb->fd, offset, rw_type, lck_type, (int)len));
 		}
-		return TDB_ERRCODE(TDB_ERR_LOCK, -1);
+		return -1;
 	}
 	return 0;
 }
@@ -133,10 +133,12 @@ static int _tdb_lock(struct tdb_context *tdb, int list, int ltype, int op)
 	}
 
 	if (tdb->global_lock.count) {
-		return TDB_ERRCODE(TDB_ERR_LOCK, -1);
+		tdb->ecode = TDB_ERR_LOCK;
+		return -1;
 	}
 
 	if (list < -1 || list >= (int)tdb->header.hash_size) {
+		tdb->ecode = TDB_ERR_LOCK;
 		TDB_LOG((tdb, TDB_DEBUG_ERROR,"tdb_lock: invalid list %d for ltype=%d\n", 
 			   list, ltype));
 		return -1;
@@ -228,7 +230,8 @@ int tdb_unlock(struct tdb_context *tdb, int list, int ltype)
 	}
 
 	if (tdb->global_lock.count) {
-		return TDB_ERRCODE(TDB_ERR_LOCK, -1);
+		tdb->ecode = TDB_ERR_LOCK;
+		return -1;
 	}
 
 	if (tdb->flags & TDB_NOLOCK)
@@ -301,16 +304,21 @@ int tdb_unlock(struct tdb_context *tdb, int list, int ltype)
  */
 int tdb_transaction_lock(struct tdb_context *tdb, int ltype)
 {
-	if (tdb->have_transaction_lock || tdb->global_lock.count) {
+	if (tdb->global_lock.count) {
+		return 0;
+	}
+	if (tdb->transaction_lock_count > 0) {
+		tdb->transaction_lock_count++;
 		return 0;
 	}
+
 	if (tdb->methods->tdb_brlock(tdb, TRANSACTION_LOCK, ltype, 
 				     F_SETLKW, 0, 1) == -1) {
 		TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_transaction_lock: failed to get transaction lock\n"));
 		tdb->ecode = TDB_ERR_LOCK;
 		return -1;
 	}
-	tdb->have_transaction_lock = 1;
+	tdb->transaction_lock_count++;
 	return 0;
 }
 
@@ -320,12 +328,16 @@ int tdb_transaction_lock(struct tdb_context *tdb, int ltype)
 int tdb_transaction_unlock(struct tdb_context *tdb)
 {
 	int ret;
-	if (!tdb->have_transaction_lock) {
+	if (tdb->global_lock.count) {
+		return 0;
+	}
+	if (tdb->transaction_lock_count > 1) {
+		tdb->transaction_lock_count--;
 		return 0;
 	}
 	ret = tdb->methods->tdb_brlock(tdb, TRANSACTION_LOCK, F_UNLCK, F_SETLKW, 0, 1);
 	if (ret == 0) {
-		tdb->have_transaction_lock = 0;
+		tdb->transaction_lock_count = 0;
 	}
 	return ret;
 }
@@ -341,8 +353,10 @@ static int _tdb_lockall(struct tdb_context *tdb, int ltype, int op)
 	ltype &= ~TDB_MARK_LOCK;
 
 	/* There are no locks on read-only dbs */
-	if (tdb->read_only || tdb->traverse_read)
-		return TDB_ERRCODE(TDB_ERR_LOCK, -1);
+	if (tdb->read_only || tdb->traverse_read) {
+		tdb->ecode = TDB_ERR_LOCK;
+		return -1;
+	}
 
 	if (tdb->global_lock.count && tdb->global_lock.ltype == ltype) {
 		tdb->global_lock.count++;
@@ -351,12 +365,14 @@ static int _tdb_lockall(struct tdb_context *tdb, int ltype, int op)
 
 	if (tdb->global_lock.count) {
 		/* a global lock of a different type exists */
-		return TDB_ERRCODE(TDB_ERR_LOCK, -1);
+		tdb->ecode = TDB_ERR_LOCK;
+		return -1;
 	}
 	
 	if (tdb->num_locks != 0) {
 		/* can't combine global and chain locks */
-		return TDB_ERRCODE(TDB_ERR_LOCK, -1);
+		tdb->ecode = TDB_ERR_LOCK;
+		return -1;
 	}
 
 	if (!mark_lock &&
@@ -385,11 +401,13 @@ static int _tdb_unlockall(struct tdb_context *tdb, int ltype)
 
 	/* There are no locks on read-only dbs */
 	if (tdb->read_only || tdb->traverse_read) {
-		return TDB_ERRCODE(TDB_ERR_LOCK, -1);
+		tdb->ecode = TDB_ERR_LOCK;
+		return -1;
 	}
 
 	if (tdb->global_lock.ltype != ltype || tdb->global_lock.count == 0) {
-		return TDB_ERRCODE(TDB_ERR_LOCK, -1);
+		tdb->ecode = TDB_ERR_LOCK;
+		return -1;
 	}
 
 	if (tdb->global_lock.count > 1) {
@@ -413,48 +431,58 @@ static int _tdb_unlockall(struct tdb_context *tdb, int ltype)
 /* lock entire database with write lock */
 int tdb_lockall(struct tdb_context *tdb)
 {
+	tdb_trace(tdb, "tdb_lockall");
 	return _tdb_lockall(tdb, F_WRLCK, F_SETLKW);
 }
 
 /* lock entire database with write lock - mark only */
 int tdb_lockall_mark(struct tdb_context *tdb)
 {
+	tdb_trace(tdb, "tdb_lockall_mark");
 	return _tdb_lockall(tdb, F_WRLCK | TDB_MARK_LOCK, F_SETLKW);
 }
 
 /* unlock entire database with write lock - unmark only */
 int tdb_lockall_unmark(struct tdb_context *tdb)
 {
+	tdb_trace(tdb, "tdb_lockall_unmark");
 	return _tdb_unlockall(tdb, F_WRLCK | TDB_MARK_LOCK);
 }
 
 /* lock entire database with write lock - nonblocking varient */
 int tdb_lockall_nonblock(struct tdb_context *tdb)
 {
-	return _tdb_lockall(tdb, F_WRLCK, F_SETLK);
+	int ret = _tdb_lockall(tdb, F_WRLCK, F_SETLK);
+	tdb_trace_ret(tdb, "tdb_lockall_nonblock", ret);
+	return ret;
 }
 
 /* unlock entire database with write lock */
 int tdb_unlockall(struct tdb_context *tdb)
 {
+	tdb_trace(tdb, "tdb_unlockall");
 	return _tdb_unlockall(tdb, F_WRLCK);
 }
 
 /* lock entire database with read lock */
 int tdb_lockall_read(struct tdb_context *tdb)
 {
+	tdb_trace(tdb, "tdb_lockall_read");
 	return _tdb_lockall(tdb, F_RDLCK, F_SETLKW);
 }
 
 /* lock entire database with read lock - nonblock varient */
 int tdb_lockall_read_nonblock(struct tdb_context *tdb)
 {
-	return _tdb_lockall(tdb, F_RDLCK, F_SETLK);
+	int ret = _tdb_lockall(tdb, F_RDLCK, F_SETLK);
+	tdb_trace_ret(tdb, "tdb_lockall_read_nonblock", ret);
+	return ret;
 }
 
 /* unlock entire database with read lock */
 int tdb_unlockall_read(struct tdb_context *tdb)
 {
+	tdb_trace(tdb, "tdb_unlockall_read");
 	return _tdb_unlockall(tdb, F_RDLCK);
 }
 
@@ -462,7 +490,9 @@ int tdb_unlockall_read(struct tdb_context *tdb)
    contention - it cannot guarantee how many records will be locked */
 int tdb_chainlock(struct tdb_context *tdb, TDB_DATA key)
 {
-	return tdb_lock(tdb, BUCKET(tdb->hash_fn(&key)), F_WRLCK);
+	int ret = tdb_lock(tdb, BUCKET(tdb->hash_fn(&key)), F_WRLCK);
+	tdb_trace_1rec(tdb, "tdb_chainlock", key);
+	return ret;
 }
 
 /* lock/unlock one hash chain, non-blocking. This is meant to be used
@@ -470,38 +500,46 @@ int tdb_chainlock(struct tdb_context *tdb, TDB_DATA key)
    locked */
 int tdb_chainlock_nonblock(struct tdb_context *tdb, TDB_DATA key)
 {
-	return tdb_lock_nonblock(tdb, BUCKET(tdb->hash_fn(&key)), F_WRLCK);
+	int ret = tdb_lock_nonblock(tdb, BUCKET(tdb->hash_fn(&key)), F_WRLCK);
+	tdb_trace_1rec_ret(tdb, "tdb_chainlock_nonblock", key, ret);
+	return ret;
 }
 
 /* mark a chain as locked without actually locking it. Warning! use with great caution! */
 int tdb_chainlock_mark(struct tdb_context *tdb, TDB_DATA key)
 {
-	return tdb_lock(tdb, BUCKET(tdb->hash_fn(&key)), F_WRLCK | TDB_MARK_LOCK);
+	int ret = tdb_lock(tdb, BUCKET(tdb->hash_fn(&key)), F_WRLCK | TDB_MARK_LOCK);
+	tdb_trace_1rec(tdb, "tdb_chainlock_mark", key);
+	return ret;
 }
 
 /* unmark a chain as locked without actually locking it. Warning! use with great caution! */
 int tdb_chainlock_unmark(struct tdb_context *tdb, TDB_DATA key)
 {
+	tdb_trace_1rec(tdb, "tdb_chainlock_unmark", key);
 	return tdb_unlock(tdb, BUCKET(tdb->hash_fn(&key)), F_WRLCK | TDB_MARK_LOCK);
 }
 
 int tdb_chainunlock(struct tdb_context *tdb, TDB_DATA key)
 {
+	tdb_trace_1rec(tdb, "tdb_chainunlock", key);
 	return tdb_unlock(tdb, BUCKET(tdb->hash_fn(&key)), F_WRLCK);
 }
 
 int tdb_chainlock_read(struct tdb_context *tdb, TDB_DATA key)
 {
-	return tdb_lock(tdb, BUCKET(tdb->hash_fn(&key)), F_RDLCK);
+	int ret;
+	ret = tdb_lock(tdb, BUCKET(tdb->hash_fn(&key)), F_RDLCK);
+	tdb_trace_1rec(tdb, "tdb_chainlock_read", key);
+	return ret;
 }
 
 int tdb_chainunlock_read(struct tdb_context *tdb, TDB_DATA key)
 {
+	tdb_trace_1rec(tdb, "tdb_chainunlock_read", key);
 	return tdb_unlock(tdb, BUCKET(tdb->hash_fn(&key)), F_RDLCK);
 }
 
-
-
 /* record lock stops delete underneath */
 int tdb_lock_record(struct tdb_context *tdb, tdb_off_t off)
 {