[asterisk-commits] mmichelson: branch 1.4 r155861 - /branches/1.4/channels/chan_agent.c

[SVN commits to the Asterisk project]

Author: mmichelson
Date: Mon Nov 10 15:07:39 2008
New Revision: 155861

URL: http://svn.digium.com/view/asterisk?view=rev&rev=155861
Log:
Channel drivers assume that when their indicate callback
is invoked, that the channel on which the callback was called
is locked. This patch corrects an instance in chan_agent where
a channel's indicate callback is called directly without first
locking the channel.

This was leading to some observed locking issues in chan_local,
but considering that all channel drivers operate under the
same expectations, the generic fix in chan_agent is the right
way to go.

AST-126


Modified:
    branches/1.4/channels/chan_agent.c

Modified: branches/1.4/channels/chan_agent.c
URL: http://svn.digium.com/view/asterisk/branches/1.4/channels/chan_agent.c?view=diff&rev=155861&r1=155860&r2=155861
==============================================================================
--- branches/1.4/channels/chan_agent.c (original)
+++ branches/1.4/channels/chan_agent.c Mon Nov 10 15:07:39 2008
@@ -666,9 +666,15 @@
 	struct agent_pvt *p = ast->tech_pvt;
 	int res = -1;
 	ast_mutex_lock(&p->lock);
-	if (p->chan && !ast_check_hangup(p->chan))
-		res = p->chan->tech->indicate ? p->chan->tech->indicate(p->chan, condition, data, datalen) : -1;
-	else
+	if (p->chan && !ast_check_hangup(p->chan)) {
+		while (ast_channel_trylock(p->chan)) {
+			ast_channel_unlock(ast);
+			usleep(1);
+			ast_channel_lock(ast);
+		}
+  		res = p->chan->tech->indicate ? p->chan->tech->indicate(p->chan, condition, data, datalen) : -1;
+		ast_channel_unlock(p->chan);
+	} else
 		res = 0;
 	ast_mutex_unlock(&p->lock);
 	return res;