errorignore: Added convert-error signal

The convert-error signal is emitted whenever we get a GstFlowReturn
other than GST_FLOW_OK. The handler can then decide what to convert that
into - for instance, return the same GstFlowReturn to not convert it.
The default handler will act according to the ignore-error,
ignore-notlinked, ignore-notnegotiated and convert-to properties. If a
handler is connected, these properties are ignored.

gst/debugutils/gsterrorignore.c

@@ -52,6 +52,12 @@ enum
   PROP_CONVERT_TO
 };
 
+enum
+{
+  SIGNAL_CONVERT_ERROR,
+  LAST_SIGNAL
+};
+
 static void gst_error_ignore_set_property (GObject * object, guint prop_id,
     const GValue * value, GParamSpec * pspec);
 static void gst_error_ignore_get_property (GObject * object, guint prop_id,
@@ -77,6 +83,11 @@ static gboolean gst_error_ignore_sink_event (GstPad * pad, GstObject * parent,
 static GstStateChangeReturn gst_error_ignore_change_state (GstElement * element,
     GstStateChange transition);
 
+static GstFlowReturn
+gst_error_ignore_convert_error (GstElement * element, GstFlowReturn value);
+
+static guint signals[LAST_SIGNAL] = { 0 };
+
 static void
 gst_error_ignore_class_init (GstErrorIgnoreClass * klass)
 {
@@ -124,6 +135,28 @@ gst_error_ignore_class_init (GstErrorIgnoreClass * klass)
           "Which GstFlowReturn value we should convert to when ignoring",
           GST_TYPE_FLOW_RETURN,
           GST_FLOW_NOT_LINKED, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
+
+  /**
+   * GstErrorIgnore::convert-error:
+   * @errorignore: the errorignore element that emitted the signal
+   * @value: the @GstFlowReturn encountered
+   *
+   * Emitted whenever we get a @GstFlowReturn other than GST_FLOW_OK. The
+   * handler can then decide what to convert that into - for instance, return
+   * the same @GstFlowReturn to not convert it. The default handler will act
+   * according to the ignore-error, ignore-notlinked, ignore-notnegotiated and
+   * convert-to properties. If a handler is connected, these properties are
+   * ignored. Only the first signal handler will ever be called.
+   *
+   * Returns: The @GstFlowReturn to convert into
+   *
+   * Since: 1.18
+   */
+  signals[SIGNAL_CONVERT_ERROR] =
+      g_signal_new_class_handler ("convert-error", G_TYPE_FROM_CLASS (klass),
+      G_SIGNAL_RUN_LAST, G_CALLBACK (gst_error_ignore_convert_error),
+      g_signal_accumulator_first_wins, NULL, NULL, GST_TYPE_FLOW_RETURN, 1,
+      GST_TYPE_FLOW_RETURN);
 }
 
 static void
@@ -161,16 +194,24 @@ gst_error_ignore_set_property (GObject * object, guint prop_id,
 
   switch (prop_id) {
     case PROP_IGNORE_ERROR:
+      GST_OBJECT_LOCK (self);
       self->ignore_error = g_value_get_boolean (value);
+      GST_OBJECT_UNLOCK (self);
       break;
     case PROP_IGNORE_NOTLINKED:
+      GST_OBJECT_LOCK (self);
       self->ignore_notlinked = g_value_get_boolean (value);
+      GST_OBJECT_UNLOCK (self);
       break;
     case PROP_IGNORE_NOTNEGOTIATED:
+      GST_OBJECT_LOCK (self);
       self->ignore_notnegotiated = g_value_get_boolean (value);
+      GST_OBJECT_UNLOCK (self);
       break;
     case PROP_CONVERT_TO:
+      GST_OBJECT_LOCK (self);
       self->convert_to = g_value_get_enum (value);
+      GST_OBJECT_UNLOCK (self);
       break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
@@ -186,16 +227,24 @@ gst_error_ignore_get_property (GObject * object, guint prop_id, GValue * value,
 
   switch (prop_id) {
     case PROP_IGNORE_ERROR:
+      GST_OBJECT_LOCK (self);
       g_value_set_boolean (value, self->ignore_error);
+      GST_OBJECT_UNLOCK (self);
       break;
     case PROP_IGNORE_NOTLINKED:
+      GST_OBJECT_LOCK (self);
       g_value_set_boolean (value, self->ignore_notlinked);
+      GST_OBJECT_UNLOCK (self);
       break;
     case PROP_IGNORE_NOTNEGOTIATED:
+      GST_OBJECT_LOCK (self);
       g_value_set_boolean (value, self->ignore_notnegotiated);
+      GST_OBJECT_UNLOCK (self);
       break;
     case PROP_CONVERT_TO:
+      GST_OBJECT_LOCK (self);
       g_value_set_enum (value, self->convert_to);
+      GST_OBJECT_UNLOCK (self);
       break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
@@ -214,7 +263,9 @@ gst_error_ignore_sink_event (GstPad * pad, GstObject * parent, GstEvent * event)
   switch (GST_EVENT_TYPE (event)) {
     case GST_EVENT_CAPS:
     case GST_EVENT_FLUSH_STOP:
+      GST_OBJECT_LOCK (self);
       self->keep_pushing = TRUE;
+      GST_OBJECT_UNLOCK (self);
       /* fall through */
     default:
       ret = gst_pad_event_default (pad, parent, event);
@@ -224,29 +275,52 @@ gst_error_ignore_sink_event (GstPad * pad, GstObject * parent, GstEvent * event)
   return ret;
 }
 
+static GstFlowReturn
+gst_error_ignore_convert_error (GstElement * element, GstFlowReturn value)
+{
+  GstFlowReturn ret = value;
+  GstErrorIgnore *self = GST_ERROR_IGNORE (element);
+
+  GST_OBJECT_LOCK (self);
+  if ((value == GST_FLOW_ERROR && self->ignore_error) ||
+      (value == GST_FLOW_NOT_LINKED && self->ignore_notlinked) ||
+      (value == GST_FLOW_NOT_NEGOTIATED && self->ignore_notnegotiated)) {
+    ret = self->convert_to;
+  }
+  GST_OBJECT_UNLOCK (self);
+
+  return ret;
+}
+
 static GstFlowReturn
 gst_error_ignore_sink_chain (GstPad * pad, GstObject * parent,
     GstBuffer * inbuf)
 {
   GstErrorIgnore *self = GST_ERROR_IGNORE (parent);
   GstFlowReturn ret = GST_FLOW_OK;
+  GstFlowReturn convert_to;
+  gboolean keep_pushing;
 
-  if (gst_pad_check_reconfigure (pad))
+  GST_OBJECT_LOCK (self);
-    self->keep_pushing = TRUE;
+  keep_pushing = self->keep_pushing || gst_pad_check_reconfigure (pad);
+  GST_OBJECT_UNLOCK (self);
 
-  if (self->keep_pushing) {
+  if (keep_pushing) {
     ret = gst_pad_push (self->srcpad, inbuf);
+    GST_OBJECT_LOCK (self);
     self->keep_pushing = (ret == GST_FLOW_OK);
+    GST_OBJECT_UNLOCK (self);
   } else {
     gst_buffer_unref (inbuf);
   }
 
-  if ((ret == GST_FLOW_ERROR && self->ignore_error) ||
+  if (ret == GST_FLOW_OK)
-      (ret == GST_FLOW_NOT_LINKED && self->ignore_notlinked) ||
-      (ret == GST_FLOW_NOT_NEGOTIATED && self->ignore_notnegotiated))
-    return self->convert_to;
-  else
     return ret;
+
+  g_signal_emit (self, signals[SIGNAL_CONVERT_ERROR], 0, ret, &convert_to);
+  GST_LOG_OBJECT (self, "Encountered flow error %s, converting to %s",
+      gst_flow_get_name (ret), gst_flow_get_name (convert_to));
+  return convert_to;
 }
 
 static GstStateChangeReturn
@@ -261,7 +335,9 @@ gst_error_ignore_change_state (GstElement * element, GstStateChange transition)
 
   switch (transition) {
     case GST_STATE_CHANGE_READY_TO_PAUSED:
+      GST_OBJECT_LOCK (self);
       self->keep_pushing = TRUE;
+      GST_OBJECT_UNLOCK (self);
       break;
     default:
       break;