Fix race in chromedriver webserver where a new pending connection is ignored

because the worker thread thinks the incoming queue is empty.
BUG=none
TEST=none


Review URL: http://codereview.chromium.org/6982051

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@87739 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 12 insertions, 5 deletions

diff --git a/third_party/mongoose/README.chromium b/third_party/mongoose/README.chromium
index 56532b4..e2db77b 100644
--- a/third_party/mongoose/README.chromium
+++ b/third_party/mongoose/README.chromium
@@ -1,7 +1,9 @@
-Name: mongoose
+Name: Mongoose webserver
+Short Name: mongoose
 URL: http://code.google.com/p/mongoose/
 LICENSE: MIT
 Version: 2.8
+Security Critical: no
 
 Description:
 Mongoose is an easy to use web server. It can be embedded into existing
@@ -28,4 +30,5 @@ the chrome versoin of webdriver found under the directory:
 
 Local modifications:
 -Do not check for OS_POSIX, instead just check that it is not windows.
-
+-Handle case where pthread_cond_timedwait times out but the condition predicate
+is actually true.
diff --git a/third_party/mongoose/mongoose.c b/third_party/mongoose/mongoose.c
index 24874e5..26e4077 100644
--- a/third_party/mongoose/mongoose.c
+++ b/third_party/mongoose/mongoose.c
@@ -4486,9 +4486,13 @@ get_socket(struct mg_context *ctx, struct socket *sp)
 #endif
     if (pthread_cond_timedwait(&ctx->empty_cond,
         &ctx->thr_mutex, &ts) != 0) {
-      /* Timeout! release the mutex and return */
-      (void) pthread_mutex_unlock(&ctx->thr_mutex);
-      return (FALSE);
+      // Even if the wait timed out, it is not guaranteed that the condition
+      // predicate is actually false.
+      if (ctx->sq_head == ctx->sq_tail) {
+        /* Timeout! release the mutex and return */
+        (void) pthread_mutex_unlock(&ctx->thr_mutex);
+        return (FALSE);
+      }
     }
   }
   assert(ctx->sq_head > ctx->sq_tail);