Merged revisions 107099 via svnmerge from

https://origsvn.digium.com/svn/asterisk/branches/1.4

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r107099 | russell | 2008-03-10 11:58:57 -0500 (Mon, 10 Mar 2008) | 3 lines

Fix a race condition where the generator can go away
(closes issue #12175, reported by edantie, patched by me)

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git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@107100 65c4cc65-6c06-0410-ace0-fbb531ad65f3

main/channel.c

@@ -1711,9 +1711,13 @@ static int generator_force(const void *data)
 	ast_channel_lock(chan);
 	tmp = chan->generatordata;
 	chan->generatordata = NULL;
-	generate = chan->generator->generate;
+	if (chan->generator)
+		generate = chan->generator->generate;
 	ast_channel_unlock(chan);
 
+	if (!tmp || !generate)
+		return 0;
+
 	res = generate(chan, tmp, 0, 160);
 
 	chan->generatordata = tmp;