Merged revisions 84783 via svnmerge from
authorRussell Bryant <russell@russellbryant.com>
Fri, 5 Oct 2007 16:49:16 +0000 (16:49 +0000)
committerRussell Bryant <russell@russellbryant.com>
Fri, 5 Oct 2007 16:49:16 +0000 (16:49 +0000)
https://origsvn.digium.com/svn/asterisk/branches/1.4

........
r84783 | russell | 2007-10-05 11:44:21 -0500 (Fri, 05 Oct 2007) | 4 lines

Do deadlock avoidance in a couple more places.  You can't lock two channels
at the same time without doing extra work to make sure it succeeds.
(closes issue #10895, patch by me)

........

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@84784 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channels/chan_zap.c

index f3815e3..db3ef8b 100644 (file)
@@ -3475,7 +3475,11 @@ static enum ast_bridge_result zt_bridge(struct ast_channel *c0, struct ast_chann
                return AST_BRIDGE_FAILED_NOWARN;
 
        ast_channel_lock(c0);
-       ast_channel_lock(c1);
+       while (ast_channel_trylock(c1)) {
+               ast_channel_unlock(c0);
+               usleep(1);
+               ast_channel_lock(c0);
+       }
 
        p0 = c0->tech_pvt;
        p1 = c1->tech_pvt;
@@ -3641,8 +3645,13 @@ static enum ast_bridge_result zt_bridge(struct ast_channel *c0, struct ast_chann
 
                /* Here's our main loop...  Start by locking things, looking for private parts, 
                   and then balking if anything is wrong */
+               
                ast_channel_lock(c0);
-               ast_channel_lock(c1);
+               while (ast_channel_trylock(c1)) {
+                       ast_channel_unlock(c0);
+                       usleep(1);
+                       ast_channel_lock(c0);
+               }
 
                p0 = c0->tech_pvt;
                p1 = c1->tech_pvt;