tdb2: check pid before unlock.

[ccan] / ccan / tdb2 / lock.c

diff --git a/ccan/tdb2/lock.c b/ccan/tdb2/lock.c
index 8a338cbe188c1f954ada8f701c2f7de6aeec5257..49313a5419cb7b83b7f672aaff32f5942ddf079b 100644 (file)
--- 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)
 {
@@ -224,16 +224,14 @@ 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",
@@ -378,12 +376,14 @@ static enum TDB_ERROR tdb_nest_lock(struct tdb_context *tdb,
                return TDB_SUCCESS;
        }
 
+#if 0
        if (tdb->file->num_lockrecs
            && offset >= TDB_HASH_LOCK_START
            && offset < TDB_HASH_LOCK_START + TDB_HASH_LOCK_RANGE) {
                return tdb_logerr(tdb, TDB_ERR_LOCK, TDB_LOG_ERROR,
                                  "tdb_nest_lock: already have a hash lock?");
        }
+#endif
 
        new_lck = (struct tdb_lock *)realloc(
                tdb->file->lockrecs,
@@ -849,6 +849,10 @@ 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);