--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/gstreamer_core/gst/gstghostpad.c Thu Dec 17 08:53:32 2009 +0200
@@ -0,0 +1,1115 @@
+/* GStreamer
+ * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
+ * 2000 Wim Taymans <wtay@chello.be>
+ * 2005 Andy Wingo <wingo@pobox.com>
+ * 2006 Edward Hervey <bilboed@bilboed.com>
+ *
+ * gstghostpad.c: Proxy pads
+ *
+ * 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., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+/**
+ * SECTION:gstghostpad
+ * @short_description: Pseudo link pads
+ * @see_also: #GstPad
+ *
+ * GhostPads are useful when organizing pipelines with #GstBin like elements.
+ * The idea here is to create hierarchical element graphs. The bin element
+ * contains a sub-graph. Now one would like to treat the bin-element like other
+ * #GstElements. This is where GhostPads come into play. A GhostPad acts as a
+ * proxy for another pad. Thus the bin can have sink and source ghost-pads that
+ * are associated with sink and source pads of the child elements.
+ *
+ * If the target pad is known at creation time, gst_ghost_pad_new() is the
+ * function to use to get a ghost-pad. Otherwise one can use gst_ghost_pad_new_no_target()
+ * to create the ghost-pad and use gst_ghost_pad_set_target() to establish the
+ * association later on.
+ *
+ * Note that GhostPads add overhead to the data processing of a pipeline.
+ *
+ * Last reviewed on 2005-11-18 (0.9.5)
+ */
+
+#include "gst_private.h"
+#include "gstinfo.h"
+
+#include "gstghostpad.h"
+#include "gst.h"
+
+#ifdef __SYMBIAN32__
+#include <glib_global.h>
+#endif
+
+#define GST_CAT_DEFAULT GST_CAT_PADS
+
+#define GST_TYPE_PROXY_PAD (gst_proxy_pad_get_type ())
+#define GST_IS_PROXY_PAD(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_PROXY_PAD))
+#define GST_IS_PROXY_PAD_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_PROXY_PAD))
+#define GST_PROXY_PAD(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_PROXY_PAD, GstProxyPad))
+#define GST_PROXY_PAD_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_PROXY_PAD, GstProxyPadClass))
+#define GST_PROXY_PAD_CAST(obj) ((GstProxyPad *)obj)
+
+#define GST_PROXY_PAD_TARGET(pad) (GST_PROXY_PAD_CAST (pad)->target)
+#define GST_PROXY_PAD_INTERNAL(pad) (GST_PROXY_PAD_CAST (pad)->internal)
+
+typedef struct _GstProxyPad GstProxyPad;
+typedef struct _GstProxyPadClass GstProxyPadClass;
+
+#define GST_PROXY_GET_LOCK(pad) (GST_PROXY_PAD_CAST (pad)->proxy_lock)
+#define GST_PROXY_LOCK(pad) (g_mutex_lock (GST_PROXY_GET_LOCK (pad)))
+#define GST_PROXY_UNLOCK(pad) (g_mutex_unlock (GST_PROXY_GET_LOCK (pad)))
+
+struct _GstProxyPad
+{
+ GstPad pad;
+
+ /* with PROXY_LOCK */
+ GMutex *proxy_lock;
+ GstPad *target;
+ GstPad *internal;
+};
+
+struct _GstProxyPadClass
+{
+ GstPadClass parent_class;
+
+ /*< private > */
+ gpointer _gst_reserved[1];
+};
+
+static GType gst_proxy_pad_get_type (void);
+
+G_DEFINE_TYPE (GstProxyPad, gst_proxy_pad, GST_TYPE_PAD);
+
+static GstPad *gst_proxy_pad_get_target (GstPad * pad);
+
+static void gst_proxy_pad_dispose (GObject * object);
+static void gst_proxy_pad_finalize (GObject * object);
+
+#ifndef GST_DISABLE_LOADSAVE
+static xmlNodePtr gst_proxy_pad_save_thyself (GstObject * object,
+ xmlNodePtr parent);
+#endif
+
+
+static void
+gst_proxy_pad_class_init (GstProxyPadClass * klass)
+{
+ GObjectClass *gobject_class = (GObjectClass *) klass;
+
+ gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_proxy_pad_dispose);
+ gobject_class->finalize = GST_DEBUG_FUNCPTR (gst_proxy_pad_finalize);
+
+#ifndef GST_DISABLE_LOADSAVE
+ {
+ GstObjectClass *gstobject_class = (GstObjectClass *) klass;
+
+ gstobject_class->save_thyself =
+ GST_DEBUG_FUNCPTR (gst_proxy_pad_save_thyself);
+ }
+#endif
+}
+
+static const GstQueryType *
+gst_proxy_pad_do_query_type (GstPad * pad)
+{
+ GstPad *target = gst_proxy_pad_get_target (pad);
+ const GstQueryType *res = NULL;
+
+ if (target) {
+ res = gst_pad_get_query_types (target);
+ gst_object_unref (target);
+ }
+ return res;
+}
+
+static gboolean
+gst_proxy_pad_do_event (GstPad * pad, GstEvent * event)
+{
+ gboolean res = FALSE;
+ GstPad *internal = GST_PROXY_PAD_INTERNAL (pad);
+
+ res = gst_pad_push_event (internal, event);
+
+ return res;
+}
+
+static gboolean
+gst_proxy_pad_do_query (GstPad * pad, GstQuery * query)
+{
+ gboolean res = FALSE;
+ GstPad *target = gst_proxy_pad_get_target (pad);
+
+ if (target) {
+ res = gst_pad_query (target, query);
+ gst_object_unref (target);
+ }
+
+ return res;
+}
+
+static GList *
+gst_proxy_pad_do_internal_link (GstPad * pad)
+{
+ GList *res = NULL;
+ GstPad *target = gst_proxy_pad_get_target (pad);
+
+ if (target) {
+ res = gst_pad_get_internal_links (target);
+ gst_object_unref (target);
+ }
+
+ return res;
+}
+
+static GstFlowReturn
+gst_proxy_pad_do_bufferalloc (GstPad * pad, guint64 offset, guint size,
+ GstCaps * caps, GstBuffer ** buf)
+{
+ GstFlowReturn result;
+ GstPad *internal = GST_PROXY_PAD_INTERNAL (pad);
+
+ result = gst_pad_alloc_buffer (internal, offset, size, caps, buf);
+
+ return result;
+}
+
+static GstFlowReturn
+gst_proxy_pad_do_chain (GstPad * pad, GstBuffer * buffer)
+{
+ GstFlowReturn res;
+ GstPad *internal = GST_PROXY_PAD_INTERNAL (pad);
+
+ res = gst_pad_push (internal, buffer);
+
+ return res;
+}
+
+static GstFlowReturn
+gst_proxy_pad_do_getrange (GstPad * pad, guint64 offset, guint size,
+ GstBuffer ** buffer)
+{
+ GstFlowReturn res;
+ GstPad *internal = GST_PROXY_PAD_INTERNAL (pad);
+
+ res = gst_pad_pull_range (internal, offset, size, buffer);
+
+ return res;
+}
+
+static gboolean
+gst_proxy_pad_do_checkgetrange (GstPad * pad)
+{
+ gboolean result;
+ GstPad *internal = GST_PROXY_PAD_INTERNAL (pad);
+
+ result = gst_pad_check_pull_range (internal);
+
+ return result;
+}
+
+static GstCaps *
+gst_proxy_pad_do_getcaps (GstPad * pad)
+{
+ GstPad *target = gst_proxy_pad_get_target (pad);
+ GstCaps *res;
+ GstPadTemplate *templ = GST_PAD_PAD_TEMPLATE (pad);
+
+ if (target) {
+ /* if we have a real target, proxy the call */
+ res = gst_pad_get_caps (target);
+ gst_object_unref (target);
+
+ GST_DEBUG_OBJECT (pad, "get caps of target: %" GST_PTR_FORMAT, res);
+
+ /* filter against the template */
+ if (templ && res) {
+ GstCaps *filt, *tmp;
+
+ filt = GST_PAD_TEMPLATE_CAPS (templ);
+ if (filt) {
+ tmp = gst_caps_intersect (filt, res);
+ gst_caps_unref (res);
+ res = tmp;
+ GST_DEBUG_OBJECT (pad,
+ "filtered against template gives %" GST_PTR_FORMAT, res);
+ }
+ }
+ } else {
+ /* else, if we have a template, use its caps. */
+ if (templ) {
+ res = GST_PAD_TEMPLATE_CAPS (templ);
+ GST_DEBUG_OBJECT (pad,
+ "using pad template %p with caps %p %" GST_PTR_FORMAT, templ, res,
+ res);
+ res = gst_caps_ref (res);
+ goto done;
+ }
+
+ /* last resort, any caps */
+ GST_DEBUG_OBJECT (pad, "pad has no template, returning ANY");
+ res = gst_caps_new_any ();
+ }
+
+done:
+ return res;
+}
+
+static gboolean
+gst_proxy_pad_do_acceptcaps (GstPad * pad, GstCaps * caps)
+{
+ GstPad *target = gst_proxy_pad_get_target (pad);
+ gboolean res;
+
+ if (target) {
+ res = gst_pad_accept_caps (target, caps);
+ gst_object_unref (target);
+ } else {
+ /* We don't have a target, we return TRUE and we assume that any future
+ * target will be able to deal with any configured caps. */
+ res = TRUE;
+ }
+
+ return res;
+}
+
+static void
+gst_proxy_pad_do_fixatecaps (GstPad * pad, GstCaps * caps)
+{
+ GstPad *target = gst_proxy_pad_get_target (pad);
+
+ if (target) {
+ gst_pad_fixate_caps (target, caps);
+ gst_object_unref (target);
+ }
+}
+
+static gboolean
+gst_proxy_pad_do_setcaps (GstPad * pad, GstCaps * caps)
+{
+ GstPad *target = gst_proxy_pad_get_target (pad);
+ gboolean res;
+
+ if (target) {
+ res = gst_pad_set_caps (target, caps);
+ gst_object_unref (target);
+ } else {
+ /* We don't have any target, but we shouldn't return FALSE since this
+ * would stop the actual push of a buffer (which might trigger a pad block
+ * or probe, or properly return GST_FLOW_NOT_LINKED.
+ */
+ res = TRUE;
+ }
+ return res;
+}
+
+static gboolean
+gst_proxy_pad_set_target_unlocked (GstPad * pad, GstPad * target)
+{
+ GstPad *oldtarget;
+
+ if (target) {
+ GST_LOG_OBJECT (pad, "setting target %s:%s", GST_DEBUG_PAD_NAME (target));
+
+ if (G_UNLIKELY (GST_PAD_DIRECTION (pad) != GST_PAD_DIRECTION (target)))
+ goto wrong_direction;
+ } else
+ GST_LOG_OBJECT (pad, "clearing target");
+
+ /* clear old target */
+ if ((oldtarget = GST_PROXY_PAD_TARGET (pad))) {
+ gst_object_unref (oldtarget);
+ }
+ /* set and ref new target if any */
+ if (target)
+ GST_PROXY_PAD_TARGET (pad) = gst_object_ref (target);
+ else
+ GST_PROXY_PAD_TARGET (pad) = NULL;
+
+ return TRUE;
+
+ /* ERRORS */
+wrong_direction:
+ {
+ GST_ERROR_OBJECT (pad,
+ "target pad doesn't have the same direction as ourself");
+ return FALSE;
+ }
+}
+
+static gboolean
+gst_proxy_pad_set_target (GstPad * pad, GstPad * target)
+{
+ gboolean result;
+
+ GST_PROXY_LOCK (pad);
+ result = gst_proxy_pad_set_target_unlocked (pad, target);
+ GST_PROXY_UNLOCK (pad);
+
+ return result;
+}
+
+static GstPad *
+gst_proxy_pad_get_target (GstPad * pad)
+{
+ GstPad *target;
+
+ GST_PROXY_LOCK (pad);
+ target = GST_PROXY_PAD_TARGET (pad);
+ if (target)
+ gst_object_ref (target);
+ GST_PROXY_UNLOCK (pad);
+
+ return target;
+}
+
+static void
+gst_proxy_pad_dispose (GObject * object)
+{
+ GstPad *pad = GST_PAD (object);
+ GstPad **target_p;
+
+ GST_PROXY_LOCK (pad);
+ /* remove and unref the target */
+ target_p = &GST_PROXY_PAD_TARGET (pad);
+ gst_object_replace ((GstObject **) target_p, NULL);
+ /* The internal is only cleared by GstGhostPad::dispose, since it is the
+ * parent of non-ghost GstProxyPad and owns the refcount on the internal.
+ */
+ GST_PROXY_UNLOCK (pad);
+
+ G_OBJECT_CLASS (gst_proxy_pad_parent_class)->dispose (object);
+}
+
+static void
+gst_proxy_pad_finalize (GObject * object)
+{
+ GstProxyPad *pad = GST_PROXY_PAD (object);
+
+ g_mutex_free (pad->proxy_lock);
+ pad->proxy_lock = NULL;
+
+ G_OBJECT_CLASS (gst_proxy_pad_parent_class)->finalize (object);
+}
+
+static void
+gst_proxy_pad_init (GstProxyPad * ppad)
+{
+ GstPad *pad = (GstPad *) ppad;
+
+ ppad->proxy_lock = g_mutex_new ();
+
+ gst_pad_set_query_type_function (pad,
+ GST_DEBUG_FUNCPTR (gst_proxy_pad_do_query_type));
+ gst_pad_set_event_function (pad, GST_DEBUG_FUNCPTR (gst_proxy_pad_do_event));
+ gst_pad_set_query_function (pad, GST_DEBUG_FUNCPTR (gst_proxy_pad_do_query));
+ gst_pad_set_internal_link_function (pad,
+ GST_DEBUG_FUNCPTR (gst_proxy_pad_do_internal_link));
+
+ gst_pad_set_getcaps_function (pad,
+ GST_DEBUG_FUNCPTR (gst_proxy_pad_do_getcaps));
+ gst_pad_set_acceptcaps_function (pad,
+ GST_DEBUG_FUNCPTR (gst_proxy_pad_do_acceptcaps));
+ gst_pad_set_fixatecaps_function (pad,
+ GST_DEBUG_FUNCPTR (gst_proxy_pad_do_fixatecaps));
+ gst_pad_set_setcaps_function (pad,
+ GST_DEBUG_FUNCPTR (gst_proxy_pad_do_setcaps));
+}
+
+#ifndef GST_DISABLE_LOADSAVE
+/**
+ * gst_proxy_pad_save_thyself:
+ * @pad: a ghost #GstPad to save.
+ * @parent: the parent #xmlNodePtr to save the description in.
+ *
+ * Saves the ghost pad into an xml representation.
+ *
+ * Returns: the #xmlNodePtr representation of the pad.
+ */
+static xmlNodePtr
+gst_proxy_pad_save_thyself (GstObject * object, xmlNodePtr parent)
+{
+ xmlNodePtr self;
+ GstProxyPad *proxypad;
+ GstPad *pad;
+ GstPad *peer;
+
+ g_return_val_if_fail (GST_IS_PROXY_PAD (object), NULL);
+
+ self = xmlNewChild (parent, NULL, (xmlChar *) "ghostpad", NULL);
+ xmlNewChild (self, NULL, (xmlChar *) "name",
+ (xmlChar *) GST_OBJECT_NAME (object));
+ xmlNewChild (self, NULL, (xmlChar *) "parent",
+ (xmlChar *) GST_OBJECT_NAME (GST_OBJECT_PARENT (object)));
+
+ proxypad = GST_PROXY_PAD_CAST (object);
+ pad = GST_PAD_CAST (proxypad);
+ peer = GST_PAD_CAST (pad->peer);
+
+ if (GST_IS_PAD (pad)) {
+ if (GST_PAD_IS_SRC (pad))
+ xmlNewChild (self, NULL, (xmlChar *) "direction", (xmlChar *) "source");
+ else if (GST_PAD_IS_SINK (pad))
+ xmlNewChild (self, NULL, (xmlChar *) "direction", (xmlChar *) "sink");
+ else
+ xmlNewChild (self, NULL, (xmlChar *) "direction", (xmlChar *) "unknown");
+ } else {
+ xmlNewChild (self, NULL, (xmlChar *) "direction", (xmlChar *) "unknown");
+ }
+ if (GST_IS_PAD (peer)) {
+ gchar *content = g_strdup_printf ("%s.%s",
+ GST_OBJECT_NAME (GST_PAD_PARENT (peer)), GST_PAD_NAME (peer));
+
+ xmlNewChild (self, NULL, (xmlChar *) "peer", (xmlChar *) content);
+ g_free (content);
+ } else {
+ xmlNewChild (self, NULL, (xmlChar *) "peer", NULL);
+ }
+
+ return self;
+}
+#endif /* GST_DISABLE_LOADSAVE */
+
+
+/***********************************************************************
+ * Ghost pads, implemented as a pair of proxy pads (sort of)
+ */
+
+
+struct _GstGhostPad
+{
+ GstProxyPad pad;
+
+ /* with PROXY_LOCK */
+ gulong notify_id;
+
+ /*< private > */
+ gpointer _gst_reserved[GST_PADDING];
+};
+
+struct _GstGhostPadClass
+{
+ GstProxyPadClass parent_class;
+
+ /*< private > */
+ gpointer _gst_reserved[GST_PADDING];
+};
+
+
+G_DEFINE_TYPE (GstGhostPad, gst_ghost_pad, GST_TYPE_PROXY_PAD);
+
+static void gst_ghost_pad_dispose (GObject * object);
+
+static void
+gst_ghost_pad_class_init (GstGhostPadClass * klass)
+{
+ GObjectClass *gobject_class = (GObjectClass *) klass;
+
+ gobject_class->dispose = GST_DEBUG_FUNCPTR (gst_ghost_pad_dispose);
+}
+
+/* see gstghostpad design docs */
+static gboolean
+gst_ghost_pad_internal_do_activate_push (GstPad * pad, gboolean active)
+{
+ gboolean ret;
+ GstPad *other;
+
+ GST_LOG_OBJECT (pad, "%sactivate push on %s:%s, we're ok",
+ (active ? "" : "de"), GST_DEBUG_PAD_NAME (pad));
+
+ /* in both cases (SRC and SINK) we activate just the internal pad. The targets
+ * will be activated later (or already in case of a ghost sinkpad). */
+ other = GST_PROXY_PAD_INTERNAL (pad);
+ ret = gst_pad_activate_push (other, active);
+
+ return ret;
+}
+
+static gboolean
+gst_ghost_pad_internal_do_activate_pull (GstPad * pad, gboolean active)
+{
+ gboolean ret;
+ GstPad *other;
+
+ GST_LOG_OBJECT (pad, "%sactivate pull on %s:%s", (active ? "" : "de"),
+ GST_DEBUG_PAD_NAME (pad));
+
+ if (GST_PAD_DIRECTION (pad) == GST_PAD_SRC) {
+ /* we are activated in pull mode by our peer element, which is a sinkpad
+ * that wants to operate in pull mode. This activation has to propagate
+ * upstream throught the pipeline. We call the internal activation function,
+ * which will trigger gst_ghost_pad_do_activate_pull, which propagates even
+ * further upstream */
+ GST_LOG_OBJECT (pad, "pad is src, activate internal");
+ other = GST_PROXY_PAD_INTERNAL (pad);
+ ret = gst_pad_activate_pull (other, active);
+ } else if (G_LIKELY ((other = gst_pad_get_peer (pad)))) {
+ /* We are SINK, the ghostpad is SRC, we propagate the activation upstream
+ * since we hold a pointer to the upstream peer. */
+ GST_LOG_OBJECT (pad, "activating peer");
+ ret = gst_pad_activate_pull (other, active);
+ gst_object_unref (other);
+ } else {
+ /* this is failure, we can't activate pull if there is no peer */
+ GST_LOG_OBJECT (pad, "not src and no peer, failing");
+ ret = FALSE;
+ }
+
+ return ret;
+}
+
+static gboolean
+gst_ghost_pad_do_activate_push (GstPad * pad, gboolean active)
+{
+ gboolean ret;
+ GstPad *other;
+
+ GST_LOG_OBJECT (pad, "%sactivate push on %s:%s, proxy internal",
+ (active ? "" : "de"), GST_DEBUG_PAD_NAME (pad));
+
+ /* just activate the internal pad */
+ other = GST_PROXY_PAD_INTERNAL (pad);
+ ret = gst_pad_activate_push (other, active);
+
+ return ret;
+}
+
+static gboolean
+gst_ghost_pad_do_activate_pull (GstPad * pad, gboolean active)
+{
+ gboolean ret;
+ GstPad *other;
+
+ GST_LOG_OBJECT (pad, "%sactivate pull on %s:%s", (active ? "" : "de"),
+ GST_DEBUG_PAD_NAME (pad));
+
+ if (GST_PAD_DIRECTION (pad) == GST_PAD_SRC) {
+ /* the ghostpad is SRC and activated in pull mode by its peer, call the
+ * activation function of the internal pad to propagate the activation
+ * upstream */
+ GST_LOG_OBJECT (pad, "pad is src, activate internal");
+ other = GST_PROXY_PAD_INTERNAL (pad);
+ ret = gst_pad_activate_pull (other, active);
+ } else if (G_LIKELY ((other = gst_pad_get_peer (pad)))) {
+ /* We are SINK and activated by the internal pad, propagate activation
+ * upstream because we hold a ref to the upstream peer */
+ GST_LOG_OBJECT (pad, "activating peer");
+ ret = gst_pad_activate_pull (other, active);
+ gst_object_unref (other);
+ } else {
+ /* no peer, we fail */
+ GST_LOG_OBJECT (pad, "pad not src and no peer, failing");
+ ret = FALSE;
+ }
+
+ return ret;
+}
+
+static GstPadLinkReturn
+gst_ghost_pad_do_link (GstPad * pad, GstPad * peer)
+{
+ GstPadLinkReturn ret;
+ GstPad *internal;
+
+ GST_DEBUG_OBJECT (pad, "linking ghostpad");
+
+ internal = GST_PROXY_PAD_INTERNAL (pad);
+ if (!gst_proxy_pad_set_target (internal, peer))
+ goto target_failed;
+
+ ret = GST_PAD_LINK_OK;
+ /* if we are a source pad, we should call the peer link function
+ * if the peer has one, see design docs. */
+ if (GST_PAD_IS_SRC (pad)) {
+ if (GST_PAD_LINKFUNC (peer)) {
+ ret = GST_PAD_LINKFUNC (peer) (peer, pad);
+ if (ret != GST_PAD_LINK_OK)
+ goto link_failed;
+ }
+ }
+ return ret;
+
+ /* ERRORS */
+target_failed:
+ {
+ GST_DEBUG_OBJECT (pad, "setting target failed");
+ return GST_PAD_LINK_REFUSED;
+ }
+link_failed:
+ {
+ GST_DEBUG_OBJECT (pad, "linking failed");
+ /* clear target again */
+ gst_proxy_pad_set_target (internal, NULL);
+ return ret;
+ }
+}
+
+static void
+gst_ghost_pad_do_unlink (GstPad * pad)
+{
+ GstPad *target;
+ GstPad *internal;
+
+ target = gst_proxy_pad_get_target (pad);
+ internal = GST_PROXY_PAD_INTERNAL (pad);
+
+ GST_DEBUG_OBJECT (pad, "unlinking ghostpad");
+
+ /* The target of the internal pad is no longer valid */
+ gst_proxy_pad_set_target (internal, NULL);
+
+ if (target) {
+ if (GST_PAD_UNLINKFUNC (target))
+ GST_PAD_UNLINKFUNC (target) (target);
+
+ gst_object_unref (target);
+ }
+}
+
+static void
+on_int_notify (GstPad * internal, GParamSpec * unused, GstGhostPad * pad)
+{
+ GstCaps *caps;
+
+ g_object_get (internal, "caps", &caps, NULL);
+
+ GST_OBJECT_LOCK (pad);
+ gst_caps_replace (&(GST_PAD_CAPS (pad)), caps);
+ GST_OBJECT_UNLOCK (pad);
+
+ g_object_notify (G_OBJECT (pad), "caps");
+ if (caps)
+ gst_caps_unref (caps);
+}
+
+static void
+gst_ghost_pad_init (GstGhostPad * pad)
+{
+ gst_pad_set_activatepull_function (GST_PAD_CAST (pad),
+ GST_DEBUG_FUNCPTR (gst_ghost_pad_do_activate_pull));
+ gst_pad_set_activatepush_function (GST_PAD_CAST (pad),
+ GST_DEBUG_FUNCPTR (gst_ghost_pad_do_activate_push));
+}
+
+static void
+gst_ghost_pad_dispose (GObject * object)
+{
+ GstPad *pad;
+ GstPad *internal;
+ GstPad *intpeer;
+
+ pad = GST_PAD (object);
+
+ GST_DEBUG_OBJECT (pad, "dispose");
+
+ GST_PROXY_LOCK (pad);
+ internal = GST_PROXY_PAD_INTERNAL (pad);
+
+ gst_pad_set_activatepull_function (internal, NULL);
+ gst_pad_set_activatepush_function (internal, NULL);
+
+ g_signal_handler_disconnect (internal, GST_GHOST_PAD_CAST (pad)->notify_id);
+
+ intpeer = gst_pad_get_peer (internal);
+ if (intpeer) {
+ if (GST_PAD_IS_SRC (internal))
+ gst_pad_unlink (internal, intpeer);
+ else
+ gst_pad_unlink (intpeer, internal);
+
+ gst_object_unref (intpeer);
+ }
+
+ GST_PROXY_PAD_INTERNAL (internal) = NULL;
+
+ /* disposes of the internal pad, since the ghostpad is the only possible object
+ * that has a refcount on the internal pad. */
+ gst_object_unparent (GST_OBJECT_CAST (internal));
+
+ GST_PROXY_UNLOCK (pad);
+
+ G_OBJECT_CLASS (gst_ghost_pad_parent_class)->dispose (object);
+}
+
+static GstPad *
+gst_ghost_pad_new_full (const gchar * name, GstPadDirection dir,
+ GstPadTemplate * templ)
+{
+ GstPad *ret;
+ GstPad *internal;
+ GstPadDirection otherdir;
+
+ g_return_val_if_fail (dir != GST_PAD_UNKNOWN, NULL);
+
+ /* OBJECT CREATION */
+ if (templ) {
+ ret = g_object_new (GST_TYPE_GHOST_PAD, "name", name,
+ "direction", dir, "template", templ, NULL);
+ } else {
+ ret = g_object_new (GST_TYPE_GHOST_PAD, "name", name,
+ "direction", dir, NULL);
+ }
+
+ /* Set directional padfunctions for ghostpad */
+ if (dir == GST_PAD_SINK) {
+ gst_pad_set_bufferalloc_function (ret,
+ GST_DEBUG_FUNCPTR (gst_proxy_pad_do_bufferalloc));
+ gst_pad_set_chain_function (ret,
+ GST_DEBUG_FUNCPTR (gst_proxy_pad_do_chain));
+ } else {
+ gst_pad_set_getrange_function (ret,
+ GST_DEBUG_FUNCPTR (gst_proxy_pad_do_getrange));
+ gst_pad_set_checkgetrange_function (ret,
+ GST_DEBUG_FUNCPTR (gst_proxy_pad_do_checkgetrange));
+ }
+
+ /* link/unlink functions */
+ gst_pad_set_link_function (ret, GST_DEBUG_FUNCPTR (gst_ghost_pad_do_link));
+ gst_pad_set_unlink_function (ret,
+ GST_DEBUG_FUNCPTR (gst_ghost_pad_do_unlink));
+
+
+ /* INTERNAL PAD, it always exists and is child of the ghostpad */
+ otherdir = (dir == GST_PAD_SRC) ? GST_PAD_SINK : GST_PAD_SRC;
+ if (templ) {
+ internal =
+ g_object_new (GST_TYPE_PROXY_PAD, "name", NULL,
+ "direction", otherdir, "template", templ, NULL);
+ } else {
+ internal =
+ g_object_new (GST_TYPE_PROXY_PAD, "name", NULL,
+ "direction", otherdir, NULL);
+ }
+ GST_PAD_UNSET_FLUSHING (internal);
+
+ /* Set directional padfunctions for internal pad */
+ if (dir == GST_PAD_SRC) {
+ gst_pad_set_bufferalloc_function (internal,
+ GST_DEBUG_FUNCPTR (gst_proxy_pad_do_bufferalloc));
+ gst_pad_set_chain_function (internal,
+ GST_DEBUG_FUNCPTR (gst_proxy_pad_do_chain));
+ } else {
+ gst_pad_set_getrange_function (internal,
+ GST_DEBUG_FUNCPTR (gst_proxy_pad_do_getrange));
+ gst_pad_set_checkgetrange_function (internal,
+ GST_DEBUG_FUNCPTR (gst_proxy_pad_do_checkgetrange));
+ }
+
+ GST_PROXY_LOCK (ret);
+
+ /* now make the ghostpad a parent of the internal pad */
+ if (!gst_object_set_parent (GST_OBJECT_CAST (internal),
+ GST_OBJECT_CAST (ret)))
+ goto parent_failed;
+
+ /* The ghostpad is the parent of the internal pad and is the only object that
+ * can have a refcount on the internal pad.
+ * At this point, the GstGhostPad has a refcount of 1, and the internal pad has
+ * a refcount of 1.
+ * When the refcount of the GstGhostPad drops to 0, the ghostpad will dispose
+ * it's refcount on the internal pad in the dispose method by un-parenting it.
+ * This is why we don't take extra refcounts in the assignments below
+ */
+ GST_PROXY_PAD_INTERNAL (ret) = internal;
+ GST_PROXY_PAD_INTERNAL (internal) = ret;
+
+ /* could be more general here, iterating over all writable properties...
+ * taking the short road for now tho */
+ GST_GHOST_PAD_CAST (ret)->notify_id =
+ g_signal_connect (internal, "notify::caps", G_CALLBACK (on_int_notify),
+ ret);
+
+ /* call function to init values of the pad caps */
+ on_int_notify (internal, NULL, GST_GHOST_PAD_CAST (ret));
+
+ /* special activation functions for the internal pad */
+ gst_pad_set_activatepull_function (internal,
+ GST_DEBUG_FUNCPTR (gst_ghost_pad_internal_do_activate_pull));
+ gst_pad_set_activatepush_function (internal,
+ GST_DEBUG_FUNCPTR (gst_ghost_pad_internal_do_activate_push));
+
+ GST_PROXY_UNLOCK (ret);
+
+ return ret;
+
+ /* ERRORS */
+parent_failed:
+ {
+ GST_WARNING_OBJECT (ret, "Could not set internal pad %s:%s",
+ GST_DEBUG_PAD_NAME (internal));
+ g_critical ("Could not set internal pad %s:%s",
+ GST_DEBUG_PAD_NAME (internal));
+ GST_PROXY_UNLOCK (ret);
+ gst_object_unref (ret);
+ gst_object_unref (internal);
+ return NULL;
+ }
+}
+
+/**
+ * gst_ghost_pad_new_no_target:
+ * @name: the name of the new pad, or NULL to assign a default name.
+ * @dir: the direction of the ghostpad
+ *
+ * Create a new ghostpad without a target with the given direction.
+ * A target can be set on the ghostpad later with the
+ * gst_ghost_pad_set_target() function.
+ *
+ * The created ghostpad will not have a padtemplate.
+ *
+ * Returns: a new #GstPad, or NULL in case of an error.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+GstPad *
+gst_ghost_pad_new_no_target (const gchar * name, GstPadDirection dir)
+{
+ GstPad *ret;
+
+ g_return_val_if_fail (dir != GST_PAD_UNKNOWN, NULL);
+
+ GST_LOG ("name:%s, direction:%d", GST_STR_NULL (name), dir);
+
+ ret = gst_ghost_pad_new_full (name, dir, NULL);
+
+ return ret;
+}
+
+/**
+ * gst_ghost_pad_new:
+ * @name: the name of the new pad, or NULL to assign a default name.
+ * @target: the pad to ghost.
+ *
+ * Create a new ghostpad with @target as the target. The direction will be taken
+ * from the target pad. @target must be unlinked.
+ *
+ * Will ref the target.
+ *
+ * Returns: a new #GstPad, or NULL in case of an error.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+GstPad *
+gst_ghost_pad_new (const gchar * name, GstPad * target)
+{
+ GstPad *ret;
+
+ g_return_val_if_fail (GST_IS_PAD (target), NULL);
+ g_return_val_if_fail (!gst_pad_is_linked (target), NULL);
+
+ GST_LOG ("name:%s, target:%s:%s", GST_STR_NULL (name),
+ GST_DEBUG_PAD_NAME (target));
+
+ if ((ret = gst_ghost_pad_new_no_target (name, GST_PAD_DIRECTION (target))))
+ if (!gst_ghost_pad_set_target (GST_GHOST_PAD_CAST (ret), target))
+ goto set_target_failed;
+
+ return ret;
+
+ /* ERRORS */
+set_target_failed:
+ {
+ GST_WARNING_OBJECT (ret, "failed to set target %s:%s",
+ GST_DEBUG_PAD_NAME (target));
+ gst_object_unref (ret);
+ return NULL;
+ }
+}
+
+/**
+ * gst_ghost_pad_new_from_template:
+ * @name: the name of the new pad, or NULL to assign a default name.
+ * @target: the pad to ghost.
+ * @templ: the #GstPadTemplate to use on the ghostpad.
+ *
+ * Create a new ghostpad with @target as the target. The direction will be taken
+ * from the target pad. The template used on the ghostpad will be @template.
+ *
+ * Will ref the target.
+ *
+ * Returns: a new #GstPad, or NULL in case of an error.
+ *
+ * Since: 0.10.10
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+
+GstPad *
+gst_ghost_pad_new_from_template (const gchar * name, GstPad * target,
+ GstPadTemplate * templ)
+{
+ GstPad *ret;
+
+ g_return_val_if_fail (GST_IS_PAD (target), NULL);
+ g_return_val_if_fail (!gst_pad_is_linked (target), NULL);
+ g_return_val_if_fail (templ != NULL, NULL);
+ g_return_val_if_fail (GST_PAD_TEMPLATE_DIRECTION (templ) ==
+ GST_PAD_DIRECTION (target), NULL);
+
+ GST_LOG ("name:%s, target:%s:%s, templ:%p", GST_STR_NULL (name),
+ GST_DEBUG_PAD_NAME (target), templ);
+
+ if ((ret = gst_ghost_pad_new_full (name, GST_PAD_DIRECTION (target), templ)))
+ if (!gst_ghost_pad_set_target (GST_GHOST_PAD_CAST (ret), target))
+ goto set_target_failed;
+
+ return ret;
+
+ /* ERRORS */
+set_target_failed:
+ {
+ GST_WARNING_OBJECT (ret, "failed to set target %s:%s",
+ GST_DEBUG_PAD_NAME (target));
+ gst_object_unref (ret);
+ return NULL;
+ }
+}
+
+/**
+ * gst_ghost_pad_new_no_target_from_template:
+ * @name: the name of the new pad, or NULL to assign a default name.
+ * @templ: the #GstPadTemplate to create the ghostpad from.
+ *
+ * Create a new ghostpad based on @templ, without setting a target. The
+ * direction will be taken from the @templ.
+ *
+ * Returns: a new #GstPad, or NULL in case of an error.
+ *
+ * Since: 0.10.10
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+GstPad *
+gst_ghost_pad_new_no_target_from_template (const gchar * name,
+ GstPadTemplate * templ)
+{
+ GstPad *ret;
+
+ g_return_val_if_fail (templ != NULL, NULL);
+
+ ret =
+ gst_ghost_pad_new_full (name, GST_PAD_TEMPLATE_DIRECTION (templ), templ);
+
+ return ret;
+}
+
+/**
+ * gst_ghost_pad_get_target:
+ * @gpad: the #GstGhostpad
+ *
+ * Get the target pad of #gpad. Unref target pad after usage.
+ *
+ * Returns: the target #GstPad, can be NULL if the ghostpad
+ * has no target set. Unref target pad after usage.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+GstPad *
+gst_ghost_pad_get_target (GstGhostPad * gpad)
+{
+ GstPad *ret;
+
+ g_return_val_if_fail (GST_IS_GHOST_PAD (gpad), NULL);
+
+ ret = gst_proxy_pad_get_target (GST_PAD_CAST (gpad));
+
+ GST_DEBUG_OBJECT (gpad, "get target %s:%s", GST_DEBUG_PAD_NAME (ret));
+
+ return ret;
+}
+
+/**
+ * gst_ghost_pad_set_target:
+ * @gpad: the #GstGhostpad
+ * @newtarget: the new pad target
+ *
+ * Set the new target of the ghostpad @gpad. Any existing target
+ * is unlinked and links to the new target are established.
+ *
+ * Returns: TRUE if the new target could be set. This function can return FALSE
+ * when the internal pads could not be linked.
+ */
+#ifdef __SYMBIAN32__
+EXPORT_C
+#endif
+
+gboolean
+gst_ghost_pad_set_target (GstGhostPad * gpad, GstPad * newtarget)
+{
+ GstPad *internal;
+ GstPad *oldtarget;
+ gboolean result;
+ GstPadLinkReturn lret;
+
+ g_return_val_if_fail (GST_IS_GHOST_PAD (gpad), FALSE);
+
+ GST_PROXY_LOCK (gpad);
+ internal = GST_PROXY_PAD_INTERNAL (gpad);
+
+ GST_DEBUG_OBJECT (gpad, "set target %s:%s", GST_DEBUG_PAD_NAME (newtarget));
+
+ /* clear old target */
+ if ((oldtarget = GST_PROXY_PAD_TARGET (gpad))) {
+ /* if we have an internal pad, unlink */
+ if (internal) {
+ if (GST_PAD_IS_SRC (internal))
+ gst_pad_unlink (internal, oldtarget);
+ else
+ gst_pad_unlink (oldtarget, internal);
+ }
+ }
+
+ result = gst_proxy_pad_set_target_unlocked (GST_PAD_CAST (gpad), newtarget);
+
+ if (result && newtarget) {
+ /* and link to internal pad */
+ GST_DEBUG_OBJECT (gpad, "connecting internal pad to target");
+
+ if (GST_PAD_IS_SRC (internal))
+ lret = gst_pad_link (internal, newtarget);
+ else
+ lret = gst_pad_link (newtarget, internal);
+
+ if (lret != GST_PAD_LINK_OK)
+ goto link_failed;
+ }
+ GST_PROXY_UNLOCK (gpad);
+
+ return result;
+
+ /* ERRORS */
+link_failed:
+ {
+ GST_WARNING_OBJECT (gpad, "could not link internal and target, reason:%d",
+ lret);
+ /* and unset target again */
+ gst_proxy_pad_set_target_unlocked (GST_PAD_CAST (gpad), NULL);
+ GST_PROXY_UNLOCK (gpad);
+ return FALSE;
+ }
+}