[Levent-commits] [Libevent/master 5/6] Fix an evdns lock violation.

[Nick M. <ni...@us...>]

Author: Zhuang Yuyao <ml...@gm...>
Date: Fri, 27 Nov 2009 16:02:49 -0500
Subject: Fix an evdns lock violation.
Commit: 2df1f82bfa1b432a277b0e1f8fc65aed7898f5e5

Original message:

   evdns contains a bug related to thread lock.

   enable thread lock by evthread_use_pthreads() will cause successive
   evdns_base_resolve_ipv4() (and other resolve functions i think) to
   hang on EVDNS_LOCK(base) after one or several successful call to
   evdns_base_resolve_ipv4().
---
 evdns.c |    6 ++++--
 1 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/evdns.c b/evdns.c
index 097dae1..1a59170 100644
--- a/evdns.c
+++ b/evdns.c
@@ -616,8 +616,9 @@ nameserver_failed(struct nameserver *const ns, const char *msg) {
 }
 
 static void
-nameserver_up(struct nameserver *const ns) {
-	EVDNS_LOCK(ns->base);
+nameserver_up(struct nameserver *const ns)
+{
+	ASSERT_LOCKED(ns->base);
 	if (ns->state) return;
 	log(EVDNS_LOG_WARN, "Nameserver %s is back up",
 	    debug_ntop((struct sockaddr *)&ns->address));
@@ -3895,6 +3896,7 @@ evdns_getaddrinfo_timeout_cb(evutil_socket_t fd, short what, void *ptr)
 		v4_timedout = 1;
 		EVDNS_LOCK(data->evdns_base);
 		++data->evdns_base->getaddrinfo_ipv4_timeouts;
+		EVDNS_UNLOCK(data->evdns_base);
 	}
 	if (data->ipv6_request.r) {
 		evdns_cancel_request(NULL, data->ipv6_request.r);
-- 
1.6.3