From: Andre Noll <maan@systemlinux.org>
Date: Mon, 3 Feb 2014 20:06:00 +0000 (+0100)
Subject: ao_write: Avoid segfault on exit.
X-Git-Tag: v0.5.3~20^2~5
X-Git-Url: http://git.tuebingen.mpg.de/?p=paraslash.git;a=commitdiff_plain;h=5323dab36cfea7ee18f6ade7e38f1218cd7a9ea5

ao_write: Avoid segfault on exit.

If para_audiod is terminated by a signal it calls the ->close() method
of each active writer. In this method the ao writer calls ao_close()
and frees all resources but leaves the play thread active. So the
thread continues to run, prints

	ao_alsa ERROR: write error: File descriptor in bad state

and probably crashes afterwards due to accessing freed memory. Fix this
by cancelling the thread in ->close() if it exists. Ironically enough,
this re-introduces a call to pthread_join(), but it's OK here since
we the cancelled thread should exit immediately (so we don't block),
and we are about to exit anyway.
---

diff --git a/ao_write.c b/ao_write.c
index a2e86ed2..12ab77fe 100644
--- a/ao_write.c
+++ b/ao_write.c
@@ -39,6 +39,10 @@ static void aow_close(struct writer_node *wn)
 
 	if (!pawd)
 		return;
+	if (pawd->thread_btrn) {
+		pthread_cancel(pawd->thread);
+		pthread_join(pawd->thread, NULL);
+	}
 	ao_close(pawd->dev);
 	free(pawd);
 	wn->private_data = NULL;