/* GStreamer valve element * Copyright 2007-2009 Collabora Ltd * @author: Olivier Crete * Copyright 2007-2009 Nokia Corporation * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Library General Public * License as published by the Free Software Foundation; either * version 2 of the License, or (at your option) any later version. * * This library is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Library General Public License for more details. * * You should have received a copy of the GNU Library General Public * License along with this library; if not, write to the * Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, * Boston, MA 02110-1301, USA. * */ /** * SECTION:element-valve * * The valve is a simple element that drops buffers when the #GstValve:drop * property is set to %TRUE and lets then through otherwise. * * Any downstream error received while the #GstValve:drop property is %FALSE * is ignored. So downstream element can be set to %GST_STATE_NULL and removed, * without using pad blocking. * * This element was previously part of gst-plugins-farsight, and then * gst-plugins-bad. * * Documentation last reviewed on 2010-12-30 (0.10.31) */ #ifdef HAVE_CONFIG_H #include "config.h" #endif #include "gstvalve.h" #include GST_DEBUG_CATEGORY_STATIC (valve_debug); #define GST_CAT_DEFAULT (valve_debug) static GstStaticPadTemplate sinktemplate = GST_STATIC_PAD_TEMPLATE ("sink", GST_PAD_SINK, GST_PAD_ALWAYS, GST_STATIC_CAPS_ANY); static GstStaticPadTemplate srctemplate = GST_STATIC_PAD_TEMPLATE ("src", GST_PAD_SRC, GST_PAD_ALWAYS, GST_STATIC_CAPS_ANY); enum { PROP_0, PROP_DROP }; #define DEFAULT_DROP FALSE static void gst_valve_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec); static void gst_valve_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec); static GstFlowReturn gst_valve_chain (GstPad * pad, GstObject * parent, GstBuffer * buffer); static gboolean gst_valve_event (GstPad * pad, GstObject * parent, GstEvent * event); static gboolean gst_valve_query (GstPad * pad, GstObject * parent, GstQuery * query); #define _do_init \ GST_DEBUG_CATEGORY_INIT (valve_debug, "valve", 0, "Valve"); #define gst_valve_parent_class parent_class G_DEFINE_TYPE_WITH_CODE (GstValve, gst_valve, GST_TYPE_ELEMENT, _do_init); static void gst_valve_class_init (GstValveClass * klass) { GObjectClass *gobject_class; GstElementClass *gstelement_class; gobject_class = (GObjectClass *) klass; gstelement_class = (GstElementClass *) (klass); gobject_class->set_property = gst_valve_set_property; gobject_class->get_property = gst_valve_get_property; g_object_class_install_property (gobject_class, PROP_DROP, g_param_spec_boolean ("drop", "Drop buffers and events", "Whether to drop buffers and events or let them through", DEFAULT_DROP, G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS)); gst_element_class_add_pad_template (gstelement_class, gst_static_pad_template_get (&srctemplate)); gst_element_class_add_pad_template (gstelement_class, gst_static_pad_template_get (&sinktemplate)); gst_element_class_set_static_metadata (gstelement_class, "Valve element", "Filter", "Drops buffers and events or lets them through", "Olivier Crete "); } static void gst_valve_init (GstValve * valve) { valve->drop = FALSE; valve->discont = FALSE; valve->srcpad = gst_pad_new_from_static_template (&srctemplate, "src"); gst_pad_set_event_function (valve->srcpad, GST_DEBUG_FUNCPTR (gst_valve_event)); gst_pad_set_query_function (valve->srcpad, GST_DEBUG_FUNCPTR (gst_valve_query)); gst_element_add_pad (GST_ELEMENT (valve), valve->srcpad); valve->sinkpad = gst_pad_new_from_static_template (&sinktemplate, "sink"); gst_pad_set_chain_function (valve->sinkpad, GST_DEBUG_FUNCPTR (gst_valve_chain)); gst_pad_set_event_function (valve->sinkpad, GST_DEBUG_FUNCPTR (gst_valve_event)); gst_pad_set_query_function (valve->sinkpad, GST_DEBUG_FUNCPTR (gst_valve_query)); GST_PAD_SET_PROXY_CAPS (valve->sinkpad); gst_element_add_pad (GST_ELEMENT (valve), valve->sinkpad); } static void gst_valve_set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec) { GstValve *valve = GST_VALVE (object); switch (prop_id) { case PROP_DROP: g_atomic_int_set (&valve->drop, g_value_get_boolean (value)); gst_pad_push_event (valve->sinkpad, gst_event_new_reconfigure ()); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } static void gst_valve_get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec) { GstValve *valve = GST_VALVE (object); switch (prop_id) { case PROP_DROP: g_value_set_boolean (value, g_atomic_int_get (&valve->drop)); break; default: G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec); break; } } static gboolean forward_sticky_events (GstPad * pad, GstEvent ** event, gpointer user_data) { GstValve *valve = user_data; if (!gst_pad_push_event (valve->srcpad, gst_event_ref (*event))) valve->need_repush_sticky = TRUE; return TRUE; } static void gst_valve_repush_sticky (GstValve * valve) { valve->need_repush_sticky = FALSE; gst_pad_sticky_events_foreach (valve->sinkpad, forward_sticky_events, valve); } static GstFlowReturn gst_valve_chain (GstPad * pad, GstObject * parent, GstBuffer * buffer) { GstValve *valve = GST_VALVE (parent); GstFlowReturn ret = GST_FLOW_OK; if (g_atomic_int_get (&valve->drop)) { gst_buffer_unref (buffer); valve->discont = TRUE; } else { if (valve->discont) { buffer = gst_buffer_make_writable (buffer); GST_BUFFER_FLAG_SET (buffer, GST_BUFFER_FLAG_DISCONT); valve->discont = FALSE; } if (valve->need_repush_sticky) gst_valve_repush_sticky (valve); ret = gst_pad_push (valve->srcpad, buffer); } /* Ignore errors if "drop" was changed while the thread was blocked * downwards */ if (g_atomic_int_get (&valve->drop)) ret = GST_FLOW_OK; return ret; } static gboolean gst_valve_event (GstPad * pad, GstObject * parent, GstEvent * event) { GstValve *valve; gboolean is_sticky = GST_EVENT_IS_STICKY (event); gboolean ret = TRUE; valve = GST_VALVE (parent); if (g_atomic_int_get (&valve->drop)) { valve->need_repush_sticky |= is_sticky; gst_event_unref (event); } else { if (valve->need_repush_sticky) gst_valve_repush_sticky (valve); ret = gst_pad_event_default (pad, parent, event); } /* Ignore errors if "drop" was changed while the thread was blocked * downwards. */ if (g_atomic_int_get (&valve->drop)) { valve->need_repush_sticky |= is_sticky; ret = TRUE; } return ret; } static gboolean gst_valve_query (GstPad * pad, GstObject * parent, GstQuery * query) { GstValve *valve = GST_VALVE (parent); if (g_atomic_int_get (&valve->drop)) return FALSE; return gst_pad_query_default (pad, parent, query); }