Don't fail mysteriously on existing trace file.

[ccan] / ccan / tdb / lock.c

diff --git a/ccan/tdb/lock.c b/ccan/tdb/lock.c
index f156c0fa7b2e548640d47db23df71c9427ec73ce..326d38e70713443f86aa45e821b20e883d3df44a 100644 (file)
--- a/ccan/tdb/lock.c
+++ b/ccan/tdb/lock.c
@@ -301,16 +301,21 @@ 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 +325,16 @@ 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;
 }
@@ -413,48 +422,58 @@ 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 +481,9 @@ 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 +491,46 @@ 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)
 {