rtsp-session: Use monotonic time for RTSP session timeout

Changed RTSP session timeout handling to monotonic time
and deprecating the API for current system time.

This fixes timeouts when the system time changes.

https://bugzilla.gnome.org/show_bug.cgi?id=743346

gst/rtsp-server/rtsp-session-pool.c

@@ -470,7 +470,7 @@ gst_rtsp_session_pool_remove (GstRTSPSessionPool * pool, GstRTSPSession * sess)
 
 typedef struct
 {
-  GTimeVal now;
+  gint64 now_monotonic_time;
   GstRTSPSessionPool *pool;
   GList *removed;
 } CleanupData;
@@ -480,11 +480,13 @@ cleanup_func (gchar * sessionid, GstRTSPSession * sess, CleanupData * data)
 {
   gboolean expired;
 
-  expired = gst_rtsp_session_is_expired (sess, &data->now);
+  expired = gst_rtsp_session_is_expired_usec (sess, data->now_monotonic_time);
+
   if (expired) {
     GST_DEBUG ("session expired");
     data->removed = g_list_prepend (data->removed, g_object_ref (sess));
   }
+
   return expired;
 }
 
@@ -509,7 +511,8 @@ gst_rtsp_session_pool_cleanup (GstRTSPSessionPool * pool)
 
   priv = pool->priv;
 
-  g_get_current_time (&data.now);
+  data.now_monotonic_time = g_get_monotonic_time ();
+
   data.pool = pool;
   data.removed = NULL;
 
@@ -661,11 +664,12 @@ static void
 collect_timeout (gchar * sessionid, GstRTSPSession * sess, GstPoolSource * psrc)
 {
   gint timeout;
-  GTimeVal now;
+  gint64 now_monotonic_time;
 
-  g_get_current_time (&now);
+  now_monotonic_time = g_get_monotonic_time ();
+
+  timeout = gst_rtsp_session_next_timeout_usec (sess, now_monotonic_time);
 
-  timeout = gst_rtsp_session_next_timeout (sess, &now);
   GST_INFO ("%p: next timeout: %d", sess, timeout);
   if (psrc->timeout == -1 || timeout < psrc->timeout)
     psrc->timeout = timeout;

gst/rtsp-server/rtsp-session.c

@@ -57,9 +57,9 @@ struct _GstRTSPSessionPrivate
 
   guint timeout;
   gboolean timeout_always_visible;
-  GTimeVal create_time;         /* immutable */
   GMutex last_access_lock;
-  GTimeVal last_access;
+  gint64 last_access_monotonic_time;
+  gint64 last_access_real_time;
   gint expire_count;
 
   GList *medias;
@@ -135,7 +135,7 @@ gst_rtsp_session_init (GstRTSPSession * session)
   g_mutex_init (&priv->lock);
   g_mutex_init (&priv->last_access_lock);
   priv->timeout = DEFAULT_TIMEOUT;
-  g_get_current_time (&priv->create_time);
+
   gst_rtsp_session_touch (session);
 }
 
@@ -559,7 +559,8 @@ gst_rtsp_session_touch (GstRTSPSession * session)
   priv = session->priv;
 
   g_mutex_lock (&priv->last_access_lock);
-  g_get_current_time (&priv->last_access);
+  priv->last_access_monotonic_time = g_get_monotonic_time ();
+  priv->last_access_real_time = g_get_real_time ();
   g_mutex_unlock (&priv->last_access_lock);
 }
 
@@ -590,6 +591,52 @@ gst_rtsp_session_allow_expire (GstRTSPSession * session)
   g_atomic_int_add (&session->priv->expire_count, -1);
 }
 
+/**
+ * gst_rtsp_session_next_timeout_usec:
+ * @session: a #GstRTSPSession
+ * @now: (transfer none): the current monotonic time
+ *
+ * Get the amount of milliseconds till the session will expire.
+ *
+ * Returns: the amount of milliseconds since the session will time out.
+ */
+gint
+gst_rtsp_session_next_timeout_usec (GstRTSPSession * session, gint64 now)
+{
+  GstRTSPSessionPrivate *priv;
+  gint res;
+  GstClockTime last_access, now_ns;
+
+  g_return_val_if_fail (GST_IS_RTSP_SESSION (session), -1);
+
+  priv = session->priv;
+
+  g_mutex_lock (&priv->last_access_lock);
+  if (g_atomic_int_get (&priv->expire_count) != 0) {
+    /* touch session when the expire count is not 0 */
+    priv->last_access_monotonic_time = g_get_monotonic_time ();
+    priv->last_access_real_time = g_get_real_time ();
+  }
+
+  last_access = GST_USECOND * (priv->last_access_monotonic_time);
+
+  /* add timeout allow for 5 seconds of extra time */
+  last_access += priv->timeout * GST_SECOND + (5 * GST_SECOND);
+  g_mutex_unlock (&priv->last_access_lock);
+
+  now_ns = GST_USECOND * now;
+
+  if (last_access > now_ns) {
+    res = GST_TIME_AS_MSECONDS (last_access - now_ns);
+  } else {
+    res = 0;
+  }
+
+  return res;
+}
+
+/****** Deprecated API *******/
+
 /**
  * gst_rtsp_session_next_timeout:
  * @session: a #GstRTSPSession
@@ -598,7 +645,11 @@ gst_rtsp_session_allow_expire (GstRTSPSession * session)
  * Get the amount of milliseconds till the session will expire.
  *
  * Returns: the amount of milliseconds since the session will time out.
+ *
+ * Deprecated: Use gst_rtsp_session_next_timeout_usec() instead.
  */
+#ifndef GST_REMOVE_DEPRECATED
+#ifndef GST_DISABLE_DEPRECATED
 gint
 gst_rtsp_session_next_timeout (GstRTSPSession * session, GTimeVal * now)
 {
@@ -614,23 +665,50 @@ gst_rtsp_session_next_timeout (GstRTSPSession * session, GTimeVal * now)
   g_mutex_lock (&priv->last_access_lock);
   if (g_atomic_int_get (&priv->expire_count) != 0) {
     /* touch session when the expire count is not 0 */
-    g_get_current_time (&priv->last_access);
+    priv->last_access_monotonic_time = g_get_monotonic_time ();
+    priv->last_access_real_time = g_get_real_time ();
   }
 
-  last_access = GST_TIMEVAL_TO_TIME (priv->last_access);
+  last_access = GST_USECOND * (priv->last_access_real_time);
+
   /* add timeout allow for 5 seconds of extra time */
   last_access += priv->timeout * GST_SECOND + (5 * GST_SECOND);
   g_mutex_unlock (&priv->last_access_lock);
 
   now_ns = GST_TIMEVAL_TO_TIME (*now);
 
-  if (last_access > now_ns)
+  if (last_access > now_ns) {
     res = GST_TIME_AS_MSECONDS (last_access - now_ns);
-  else
+  } else {
     res = 0;
+  }
 
   return res;
 }
+#endif
+#endif
+
+/**
+ * gst_rtsp_session_is_expired_usec:
+ * @session: a #GstRTSPSession
+ * @now: (transfer none): the current monotonic time
+ *
+ * Check if @session timeout out.
+ *
+ * Returns: %TRUE if @session timed out
+ */
+gboolean
+gst_rtsp_session_is_expired_usec (GstRTSPSession * session, gint64 now)
+{
+  gboolean res;
+
+  res = (gst_rtsp_session_next_timeout_usec (session, now) == 0);
+
+  return res;
+}
+
+
+/****** Deprecated API *******/
 
 /**
  * gst_rtsp_session_is_expired:
@@ -640,7 +718,11 @@ gst_rtsp_session_next_timeout (GstRTSPSession * session, GTimeVal * now)
  * Check if @session timeout out.
  *
  * Returns: %TRUE if @session timed out
+ *
+ * Deprecated: Use gst_rtsp_session_is_expired_usec() instead.
  */
+#ifndef GST_REMOVE_DEPRECATED
+#ifndef GST_DISABLE_DEPRECATED
 gboolean
 gst_rtsp_session_is_expired (GstRTSPSession * session, GTimeVal * now)
 {
@@ -650,3 +732,5 @@ gst_rtsp_session_is_expired (GstRTSPSession * session, GTimeVal * now)
 
   return res;
 }
+#endif
+#endif

gst/rtsp-server/rtsp-session.h

@@ -95,8 +95,12 @@ guint                  gst_rtsp_session_get_timeout          (GstRTSPSession *se
 void                   gst_rtsp_session_touch                (GstRTSPSession *session);
 void                   gst_rtsp_session_prevent_expire       (GstRTSPSession *session);
 void                   gst_rtsp_session_allow_expire         (GstRTSPSession *session);
+gint                   gst_rtsp_session_next_timeout_usec    (GstRTSPSession *session, gint64 now);
+gboolean               gst_rtsp_session_is_expired_usec      (GstRTSPSession *session, gint64 now);
+#ifndef GST_DISABLE_DEPRECATED
 gint                   gst_rtsp_session_next_timeout         (GstRTSPSession *session, GTimeVal *now);
 gboolean               gst_rtsp_session_is_expired           (GstRTSPSession *session, GTimeVal *now);
+#endif
 
 /* handle media in a session */
 GstRTSPSessionMedia *  gst_rtsp_session_manage_media         (GstRTSPSession *sess,