Merged revisions 256014 via svnmerge from
authorRussell Bryant <russell@russellbryant.com>
Fri, 2 Apr 2010 23:46:45 +0000 (23:46 +0000)
committerRussell Bryant <russell@russellbryant.com>
Fri, 2 Apr 2010 23:46:45 +0000 (23:46 +0000)
https://origsvn.digium.com/svn/asterisk/branches/1.4

........
  r256014 | russell | 2010-04-02 18:45:56 -0500 (Fri, 02 Apr 2010) | 9 lines

  Resolve a deadlock that occurs due to a pointless call to ast_bridged_channel()

  (closes issue #16840)
  Reported by: bzing2
  Patches:
        patch.txt uploaded by bzing2 (license 902)
        issue_16840.rev1.diff uploaded by russell (license 2)
  Tested by: bzing2, russell
........

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@256015 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_local.c

index 5de9ed5..b2c7b9e 100644 (file)
@@ -292,7 +292,11 @@ static int local_answer(struct ast_channel *ast)
        return res;
 }
 
-static void check_bridge(struct local_pvt *p, int isoutbound)
+/*!
+ * \internal
+ * \note This function assumes that we're only called from the "outbound" local channel side
+ */
+static void check_bridge(struct local_pvt *p)
 {
        struct ast_channel_monitor *tmp;
        if (ast_test_flag(p, LOCAL_ALREADY_MASQED) || ast_test_flag(p, LOCAL_NO_OPTIMIZATION) || !p->chan || !p->owner || (p->chan->_bridge != ast_bridged_channel(p->chan)))
@@ -303,7 +307,7 @@ static void check_bridge(struct local_pvt *p, int isoutbound)
           frames on the owner channel (because they would be transferred to the
           outbound channel during the masquerade)
        */
-       if (isoutbound && p->chan->_bridge /* Not ast_bridged_channel!  Only go one step! */ && AST_LIST_EMPTY(&p->owner->readq)) {
+       if (p->chan->_bridge /* Not ast_bridged_channel!  Only go one step! */ && AST_LIST_EMPTY(&p->owner->readq)) {
                /* Masquerade bridged channel into owner */
                /* Lock everything we need, one by one, and give up if
                   we can't get everything.  Remember, we'll get another
@@ -337,26 +341,6 @@ static void check_bridge(struct local_pvt *p, int isoutbound)
                                ast_channel_unlock(p->chan->_bridge);
                        }
                }
-       /* We only allow masquerading in one 'direction'... it's important to preserve the state
-          (group variables, etc.) that live on p->chan->_bridge (and were put there by the dialplan)
-          when the local channels go away.
-       */
-#if 0
-       } else if (!isoutbound && p->owner && p->owner->_bridge && p->chan && AST_LIST_EMPTY(&p->chan->readq)) {
-               /* Masquerade bridged channel into chan */
-               if (!ast_mutex_trylock(&(p->owner->_bridge)->lock)) {
-                       if (!ast_check_hangup(p->owner->_bridge)) {
-                               if (!ast_mutex_trylock(&p->chan->lock)) {
-                                       if (!ast_check_hangup(p->chan)) {
-                                               ast_channel_masquerade(p->chan, p->owner->_bridge);
-                                               ast_set_flag(p, LOCAL_ALREADY_MASQED);
-                                       }
-                                       ast_mutex_unlock(&p->chan->lock);
-                               }
-                       }
-                       ast_mutex_unlock(&(p->owner->_bridge)->lock);
-               }
-#endif
        }
 }
 
@@ -377,8 +361,8 @@ static int local_write(struct ast_channel *ast, struct ast_frame *f)
        /* Just queue for delivery to the other side */
        ast_mutex_lock(&p->lock);
        isoutbound = IS_OUTBOUND(ast, p);
-       if (f && (f->frametype == AST_FRAME_VOICE || f->frametype == AST_FRAME_VIDEO))
-               check_bridge(p, isoutbound);
+       if (isoutbound && f && (f->frametype == AST_FRAME_VOICE || f->frametype == AST_FRAME_VIDEO))
+               check_bridge(p);
        if (!ast_test_flag(p, LOCAL_ALREADY_MASQED))
                res = local_queue_frame(p, isoutbound, f, ast, 1);
        else {