[asterisk-commits] russell: branch 1.4 r77943 - /branches/1.4/channels/chan_iax2.c

[SVN commits to the Asterisk project]

Author: russell
Date: Thu Aug  2 13:04:43 2007
New Revision: 77943

URL: http://svn.digium.com/view/asterisk?view=rev&rev=77943
Log:
Fix another race condition in the handling of dynamic threads.  If the dynamic
thread timed out waiting for something to do, but was acquired to perform an
action immediately afterwords, then wait on the condition again to give the
other thread a chance to finish setting up the data for what action this thread
should perform.  Otherwise, if it immediately continues, it will perform the
wrong action.
(reported on IRC by mihai, patch by me)
(related to issue #10289)

Modified:
    branches/1.4/channels/chan_iax2.c

Modified: branches/1.4/channels/chan_iax2.c
URL: http://svn.digium.com/view/asterisk/branches/1.4/channels/chan_iax2.c?view=diff&rev=77943&r1=77942&r2=77943
==============================================================================
--- branches/1.4/channels/chan_iax2.c (original)
+++ branches/1.4/channels/chan_iax2.c Thu Aug  2 13:04:43 2007
@@ -7874,14 +7874,20 @@
 			ts.tv_sec = tv.tv_sec;
 			ts.tv_nsec = tv.tv_usec * 1000;
 			if (ast_cond_timedwait(&thread->cond, &thread->lock, &ts) == ETIMEDOUT) {
-				ast_mutex_unlock(&thread->lock);
 				AST_LIST_LOCK(&dynamic_list);
 				/* Account for the case where this thread is acquired *right* after a timeout */
 				if ((t = AST_LIST_REMOVE(&dynamic_list, thread, list)))
 					iaxdynamicthreadcount--;
 				AST_LIST_UNLOCK(&dynamic_list);
-				if (t)
+				if (t) {
+					ast_mutex_unlock(&thread->lock);
 					break;		/* exiting the main loop */
+				}
+				/* Someone grabbed our thread *right* after we timed out.
+				 * Wait for them to set us up with something to do and signal
+				 * us to continue. */
+				ast_cond_timedwait(&thread->cond, &thread->lock, &ts);
+				ast_mutex_unlock(&thread->lock);
 			}
 			if (!t)
 				ast_mutex_unlock(&thread->lock);