Resolve a deadlock involving app_chanspy and masquerades.

(ABE-1936)

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@211112 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/apps/app_chanspy.c b/apps/app_chanspy.c
index 8ccfd1a0e7d36cc4827708badb6b0b8a3b944f76..91b28137f5958064ae317b69af8f099069e3676c 100644 (file)
--- a/apps/app_chanspy.c
+++ b/apps/app_chanspy.c
@@ -422,17 +422,20 @@ static const struct ast_datastore_info chanspy_ds_info = {
 
 static struct chanspy_ds *chanspy_ds_free(struct chanspy_ds *chanspy_ds)
 {
-       if (!chanspy_ds)
+       struct ast_channel *chan;
+
+       if (!chanspy_ds) {
                return NULL;
+       }
 
        ast_mutex_lock(&chanspy_ds->lock);
-       if (chanspy_ds->chan) {
+       while ((chan = chanspy_ds->chan)) {
                struct ast_datastore *datastore;
-               struct ast_channel *chan;
 
-               chan = chanspy_ds->chan;
-
-               ast_channel_lock(chan);
+               if (ast_channel_trylock(chan)) {
+                       DEADLOCK_AVOIDANCE(&chanspy_ds->lock);
+                       continue;
+               }
                if ((datastore = ast_channel_datastore_find(chan, &chanspy_ds_info, chanspy_ds->unique_id))) {
                        ast_channel_datastore_remove(chan, datastore);
                        /* chanspy_ds->chan is NULL after this call */
@@ -441,6 +444,7 @@ static struct chanspy_ds *chanspy_ds_free(struct chanspy_ds *chanspy_ds)
                        ast_channel_datastore_free(datastore);
                }
                ast_channel_unlock(chan);
+               break;
        }
        ast_mutex_unlock(&chanspy_ds->lock);