When doing an async goto, detect if the channel is already in the middle of a

masquerade.  This can happen when chan_local is trying to optimize itself out.
If this happens, fail the async goto instead of bursting into flames.

(closes issue #13435)
Reported by: geoff2010


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@141806 65c4cc65-6c06-0410-ace0-fbb531ad65f3

main/pbx.c

@@ -4609,17 +4609,23 @@ int ast_async_goto(struct ast_channel *chan, const char *context, const char *ex
 				S_OR(context, chan->context), S_OR(exten, chan->exten), priority);
 
 			/* Masquerade into temp channel */
-			ast_channel_masquerade(tmpchan, chan);
-
-			/* Grab the locks and get going */
-			ast_channel_lock(tmpchan);
-			ast_do_masquerade(tmpchan);
-			ast_channel_unlock(tmpchan);
-			/* Start the PBX going on our stolen channel */
-			if (ast_pbx_start(tmpchan)) {
-				ast_log(LOG_WARNING, "Unable to start PBX on %s\n", tmpchan->name);
+			if (ast_channel_masquerade(tmpchan, chan)) {
+				/* Failed to set up the masquerade.  It's probably chan_local
+				 * in the middle of optimizing itself out.  Sad. :( */
 				ast_hangup(tmpchan);
+				tmpchan = NULL;
 				res = -1;
+			} else {
+				/* Grab the locks and get going */
+				ast_channel_lock(tmpchan);
+				ast_do_masquerade(tmpchan);
+				ast_channel_unlock(tmpchan);
+				/* Start the PBX going on our stolen channel */
+				if (ast_pbx_start(tmpchan)) {
+					ast_log(LOG_WARNING, "Unable to start PBX on %s\n", tmpchan->name);
+					ast_hangup(tmpchan);
+					res = -1;
+				}
 			}
 		}
 	}