[glib] GCond (linux): fix g_cond_wait_until() return value on timeout

[Ryan Lortie <desrt src gnome org>]

commit 636cd00c213995ffecd302369515bc3b36257589
Author: Tim-Philipp Müller <tim centricular com>
Date:   Sat Jul 5 15:03:22 2014 +0100

    GCond (linux): fix g_cond_wait_until() return value on timeout
    
    It should return FALSE on timeout (and only on timeout), and
    TRUE otherwise.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=731986

 glib/gthread-posix.c |    5 +++--
 glib/tests/cond.c    |    6 ++++++
 2 files changed, 9 insertions(+), 2 deletions(-)
---
diff --git a/glib/gthread-posix.c b/glib/gthread-posix.c
index 54ef769..f4703f5 100644
--- a/glib/gthread-posix.c
+++ b/glib/gthread-posix.c
@@ -1415,6 +1415,7 @@ g_cond_wait_until (GCond  *cond,
   struct timespec now;
   struct timespec span;
   guint sampled;
+  int res;
 
   if (end_time < 0)
     return FALSE;
@@ -1433,10 +1434,10 @@ g_cond_wait_until (GCond  *cond,
 
   sampled = cond->i[0];
   g_mutex_unlock (mutex);
-  syscall (__NR_futex, &cond->i[0], (gsize) FUTEX_WAIT, (gsize) sampled, &span);
+  res = syscall (__NR_futex, &cond->i[0], (gsize) FUTEX_WAIT, (gsize) sampled, &span);
   g_mutex_lock (mutex);
 
-  return TRUE;
+  return (res < 0 && errno == ETIMEDOUT) ? FALSE : TRUE;
 }
 
 #endif
diff --git a/glib/tests/cond.c b/glib/tests/cond.c
index f5215e5..f9ef3e2 100644
--- a/glib/tests/cond.c
+++ b/glib/tests/cond.c
@@ -260,6 +260,12 @@ test_wait_until (void)
   /* Make sure it's after the until time */
   g_assert_cmpint (until, <=, g_get_monotonic_time ());
 
+  /* Make sure it returns FALSE on timeout */
+  until = g_get_monotonic_time () + G_TIME_SPAN_SECOND / 50;
+  g_mutex_lock (&lock);
+  g_assert (g_cond_wait_until (&cond, &lock, until) == FALSE);
+  g_mutex_unlock (&lock);
+
   g_mutex_clear (&lock);
   g_cond_clear (&cond);
 }