tdb: use tdb_nest_lock() for open lock.

[ccan] / ccan / tdb / open.c

diff --git a/ccan/tdb/open.c b/ccan/tdb/open.c
index 1d6b3ed75ab084033723122c71857a1f8d5e84d5..54a8fe57ad11a460471785dbf370f7ae1f4a9b93 100644 (file)
--- a/ccan/tdb/open.c
+++ b/ccan/tdb/open.c
@@ -161,7 +161,6 @@ struct tdb_context *tdb_open_ex(const char *name, int hash_size, int tdb_flags,
                errno = ENOMEM;
                goto fail;
        }
-
        tdb_io_init(tdb);
        tdb->fd = -1;
 #ifdef TDB_TRACE
@@ -213,11 +212,10 @@ struct tdb_context *tdb_open_ex(const char *name, int hash_size, int tdb_flags,
        }
 
        /*
-        * TDB_ALLOW_NESTING is the default behavior.
-        * Note: this may change in future versions!
+        * TDB_DISALLOW_NESTING is the default behavior.
         */
-       if (!(tdb->flags & TDB_DISALLOW_NESTING)) {
-               tdb->flags |= TDB_ALLOW_NESTING;
+       if (!(tdb->flags & TDB_ALLOW_NESTING)) {
+               tdb->flags |= TDB_DISALLOW_NESTING;
        }
 
        /* internal databases don't mmap or lock, and start off cleared */
@@ -242,8 +240,8 @@ struct tdb_context *tdb_open_ex(const char *name, int hash_size, int tdb_flags,
         fcntl(tdb->fd, F_SETFD, v | FD_CLOEXEC);
 
        /* ensure there is only one process initialising at once */
-       if (tdb->methods->brlock(tdb, F_WRLCK, GLOBAL_LOCK, 1, TDB_LOCK_WAIT) == -1) {
-               TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: failed to get global lock on %s: %s\n",
+       if (tdb_nest_lock(tdb, OPEN_LOCK, F_WRLCK, TDB_LOCK_WAIT) == -1) {
+               TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_open_ex: failed to get open lock on %s: %s\n",
                         name, strerror(errno)));
                goto fail;      /* errno set by tdb_brlock */
        }
@@ -342,7 +340,8 @@ struct tdb_context *tdb_open_ex(const char *name, int hash_size, int tdb_flags,
        {
                char tracefile[strlen(name) + 32];
 
-               sprintf(tracefile, "%s.trace.%u", name, getpid());
+               snprintf(tracefile, sizeof(tracefile),
+                        "%s.trace.%li", name, (long)getpid());
                tdb->tracefd = open(tracefile, O_WRONLY|O_CREAT|O_EXCL, 0600);
                if (tdb->tracefd >= 0) {
                        tdb_enable_seqnum(tdb);
@@ -356,9 +355,10 @@ struct tdb_context *tdb_open_ex(const char *name, int hash_size, int tdb_flags,
  internal:
        /* Internal (memory-only) databases skip all the code above to
         * do with disk files, and resume here by releasing their
-        * global lock and hooking into the active list. */
-       if (tdb->methods->brunlock(tdb, F_WRLCK, GLOBAL_LOCK, 1) == -1)
+        * open lock and hooking into the active list. */
+       if (tdb_nest_unlock(tdb, OPEN_LOCK, F_WRLCK, false) == -1) {
                goto fail;
+       }
        tdb->next = tdbs;
        tdbs = tdb;
        return tdb;
@@ -454,9 +454,7 @@ void *tdb_get_logging_private(struct tdb_context *tdb)
        return tdb->log.log_private;
 }
 
-/* reopen a tdb - this can be used after a fork to ensure that we have an independent
-   seek pointer from our parent and to re-establish locks */
-int tdb_reopen(struct tdb_context *tdb)
+static int tdb_reopen_internal(struct tdb_context *tdb, bool active_lock)
 {
        struct stat st;
 
@@ -464,7 +462,7 @@ int tdb_reopen(struct tdb_context *tdb)
                return 0; /* Nothing to do. */
        }
 
-       if (tdb->num_locks != 0 || tdb->global_lock.count) {
+       if (tdb_have_extra_locks(tdb)) {
                TDB_LOG((tdb, TDB_DEBUG_ERROR, "tdb_reopen: reopen not allowed with locks held\n"));
                goto fail;
        }
@@ -485,11 +483,6 @@ int tdb_reopen(struct tdb_context *tdb)
                TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_reopen: open failed (%s)\n", strerror(errno)));
                goto fail;
        }
-       if ((tdb->flags & TDB_CLEAR_IF_FIRST) && 
-           (tdb->methods->brlock(tdb, F_RDLCK, ACTIVE_LOCK, 1, TDB_LOCK_WAIT) == -1)) {
-               TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_reopen: failed to obtain active lock\n"));
-               goto fail;
-       }
        if (fstat(tdb->fd, &st) != 0) {
                TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_reopen: fstat failed (%s)\n", strerror(errno)));
                goto fail;
@@ -500,6 +493,12 @@ int tdb_reopen(struct tdb_context *tdb)
        }
        tdb_mmap(tdb);
 
+       if (active_lock &&
+           (tdb->methods->brlock(tdb, F_RDLCK, ACTIVE_LOCK, 1, TDB_LOCK_WAIT) == -1)) {
+               TDB_LOG((tdb, TDB_DEBUG_FATAL, "tdb_reopen: failed to obtain active lock\n"));
+               goto fail;
+       }
+
        return 0;
 
 fail:
@@ -507,12 +506,21 @@ fail:
        return -1;
 }
 
+/* reopen a tdb - this can be used after a fork to ensure that we have an independent
+   seek pointer from our parent and to re-establish locks */
+int tdb_reopen(struct tdb_context *tdb)
+{
+       return tdb_reopen_internal(tdb, tdb->flags & TDB_CLEAR_IF_FIRST);
+}
+
 /* reopen all tdb's */
 int tdb_reopen_all(int parent_longlived)
 {
        struct tdb_context *tdb;
 
        for (tdb=tdbs; tdb; tdb = tdb->next) {
+               bool active_lock = (tdb->flags & TDB_CLEAR_IF_FIRST);
+
                /*
                 * If the parent is longlived (ie. a
                 * parent daemon architecture), we know
@@ -526,10 +534,10 @@ int tdb_reopen_all(int parent_longlived)
                 */
                if (parent_longlived) {
                        /* Ensure no clear-if-first. */
-                       tdb->flags &= ~TDB_CLEAR_IF_FIRST;
+                       active_lock = false;
                }
 
-               if (tdb_reopen(tdb) != 0)
+               if (tdb_reopen_internal(tdb, active_lock) != 0)
                        return -1;
        }