gstreamer/gst/autodetect/gstautoaudiosink.c
Tim-Philipp Müller 835264e18d gst/autodetect/gstautoaudiosink.c: When we can't find a usable audiosink, don't error out, but use a fake sink instea...
Original commit message from CVS:
* gst/autodetect/gstautoaudiosink.c:
(gst_auto_audio_sink_find_best):
When we can't find a usable audiosink, don't error out,
but use a fake sink instead and post a warning message
on the bus (#341278).
2006-08-16 10:53:32 +00:00

310 lines
9.2 KiB
C

/* GStreamer
* (c) 2005 Ronald S. Bultje <rbultje@ronald.bitfreak.net>
*
* 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:element-autoaudiosink
* @see_also: autovideosink, alsasink, osssink
*
* <refsect2>
* <para>
* autoaudiosink is an audio sink that automatically detects an appropriate
* audio sink to use. It does so by scanning the registry for all elements
* that have <quote>Sink</quote> and <quote>Audio</quote> in the class field
* of their element information, and also have a non-zero autoplugging rank.
* </para>
* <title>Example launch line</title>
* <para>
* <programlisting>
* gst-launch -v -m audiotestsrc ! audioconvert ! audioresample ! autoaudiosink
* </programlisting>
* </para>
* </refsect2>
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <string.h>
#include "gstautoaudiosink.h"
#include "gstautodetect.h"
static GstStateChangeReturn
gst_auto_audio_sink_change_state (GstElement * element,
GstStateChange transition);
GST_BOILERPLATE (GstAutoAudioSink, gst_auto_audio_sink, GstBin, GST_TYPE_BIN);
static void
gst_auto_audio_sink_base_init (gpointer klass)
{
GstElementClass *eklass = GST_ELEMENT_CLASS (klass);
const GstElementDetails gst_auto_audio_sink_details =
GST_ELEMENT_DETAILS ("Auto audio sink",
"Sink/Audio",
"Wrapper audio sink for automatically detected audio sink",
"Ronald Bultje <rbultje@ronald.bitfreak.net>");
GstStaticPadTemplate sink_template = GST_STATIC_PAD_TEMPLATE ("sink",
GST_PAD_SINK,
GST_PAD_ALWAYS,
GST_STATIC_CAPS_ANY);
gst_element_class_add_pad_template (eklass,
gst_static_pad_template_get (&sink_template));
gst_element_class_set_details (eklass, &gst_auto_audio_sink_details);
}
static void
gst_auto_audio_sink_class_init (GstAutoAudioSinkClass * klass)
{
GstElementClass *eklass = GST_ELEMENT_CLASS (klass);
eklass->change_state = GST_DEBUG_FUNCPTR (gst_auto_audio_sink_change_state);
}
/*
* Hack to make initial linking work; ideally, this'd work even when
* no target has been assigned to the ghostpad yet.
*/
static void
gst_auto_audio_sink_reset (GstAutoAudioSink * sink)
{
GstPad *targetpad;
/* fakesink placeholder */
if (sink->kid) {
gst_element_set_state (sink->kid, GST_STATE_NULL);
gst_bin_remove (GST_BIN (sink), sink->kid);
}
sink->kid = gst_element_factory_make ("fakesink", "tempsink");
gst_bin_add (GST_BIN (sink), sink->kid);
/* pad */
targetpad = gst_element_get_pad (sink->kid, "sink");
gst_ghost_pad_set_target (GST_GHOST_PAD (sink->pad), targetpad);
gst_object_unref (targetpad);
}
static void
gst_auto_audio_sink_init (GstAutoAudioSink * sink,
GstAutoAudioSinkClass * g_class)
{
sink->pad = gst_ghost_pad_new_no_target ("sink", GST_PAD_SINK);
gst_element_add_pad (GST_ELEMENT (sink), sink->pad);
gst_auto_audio_sink_reset (sink);
GST_OBJECT_FLAG_SET (sink, GST_ELEMENT_IS_SINK);
}
static gboolean
gst_auto_audio_sink_factory_filter (GstPluginFeature * feature, gpointer data)
{
guint rank;
const gchar *klass;
/* we only care about element factories */
if (!GST_IS_ELEMENT_FACTORY (feature))
return FALSE;
/* audio sinks */
klass = gst_element_factory_get_klass (GST_ELEMENT_FACTORY (feature));
if (!(strstr (klass, "Sink") && strstr (klass, "Audio")))
return FALSE;
/* only select elements with autoplugging rank */
rank = gst_plugin_feature_get_rank (feature);
if (rank < GST_RANK_MARGINAL)
return FALSE;
return TRUE;
}
static gint
gst_auto_audio_sink_compare_ranks (GstPluginFeature * f1, GstPluginFeature * f2)
{
gint diff;
diff = gst_plugin_feature_get_rank (f2) - gst_plugin_feature_get_rank (f1);
if (diff != 0)
return diff;
return strcmp (gst_plugin_feature_get_name (f2),
gst_plugin_feature_get_name (f1));
}
static GstElement *
gst_auto_audio_sink_create_element_with_pretty_name (GstAutoAudioSink * sink,
GstElementFactory * factory)
{
GstElement *element;
gchar *name, *marker;
marker = g_strdup (GST_PLUGIN_FEATURE (factory)->name);
if (g_str_has_suffix (marker, "sink"))
marker[strlen (marker) - 4] = '\0';
if (g_str_has_prefix (marker, "gst"))
g_memmove (marker, marker + 3, strlen (marker + 3) + 1);
name = g_strdup_printf ("%s-actual-sink-%s", GST_OBJECT_NAME (sink), marker);
g_free (marker);
element = gst_element_factory_create (factory, name);
g_free (name);
return element;
}
static GstElement *
gst_auto_audio_sink_find_best (GstAutoAudioSink * sink)
{
GList *list, *item;
GstElement *choice = NULL;
GstMessage *message = NULL;
GSList *errors = NULL;
GstBus *bus = gst_bus_new ();
list = gst_registry_feature_filter (gst_registry_get_default (),
(GstPluginFeatureFilter) gst_auto_audio_sink_factory_filter, FALSE, sink);
list = g_list_sort (list, (GCompareFunc) gst_auto_audio_sink_compare_ranks);
/* We don't treat sound server sinks special. Our policy is that sound
* server sinks that have a rank must not auto-spawn a daemon under any
* circumstances, so there's nothing for us to worry about here */
GST_LOG_OBJECT (sink, "Trying to find usable audio devices ...");
for (item = list; item != NULL; item = item->next) {
GstElementFactory *f = GST_ELEMENT_FACTORY (item->data);
GstElement *el;
if ((el = gst_auto_audio_sink_create_element_with_pretty_name (sink, f))) {
GstStateChangeReturn ret;
GST_DEBUG_OBJECT (sink, "Testing %s", GST_PLUGIN_FEATURE (f)->name);
gst_element_set_bus (el, bus);
ret = gst_element_set_state (el, GST_STATE_READY);
if (ret == GST_STATE_CHANGE_SUCCESS) {
gst_element_set_state (el, GST_STATE_NULL);
GST_DEBUG_OBJECT (sink, "This worked!");
choice = el;
break;
}
/* collect all error messages */
while ((message = gst_bus_pop (bus))) {
if (GST_MESSAGE_TYPE (message) == GST_MESSAGE_ERROR) {
GST_DEBUG_OBJECT (sink, "error message %" GST_PTR_FORMAT, message);
errors = g_slist_append (errors, message);
} else {
gst_message_unref (message);
}
}
gst_element_set_state (el, GST_STATE_NULL);
gst_object_unref (el);
}
}
GST_DEBUG_OBJECT (sink, "done trying");
if (!choice) {
if (errors) {
/* FIXME: we forward the first error for now; but later on it might make
* sense to actually analyse them */
gst_message_ref (GST_MESSAGE (errors->data));
GST_DEBUG_OBJECT (sink, "reposting message %p", errors->data);
gst_element_post_message (GST_ELEMENT (sink), GST_MESSAGE (errors->data));
} else {
/* send warning message to application and use a fakesink */
GST_ELEMENT_WARNING (sink, RESOURCE, NOT_FOUND, (NULL),
("Failed to find a usable audio sink"));
choice = gst_element_factory_make ("fakesink", "fake-audio-sink");
g_object_set (choice, "sync", TRUE, NULL);
gst_element_set_state (choice, GST_STATE_READY);
}
}
gst_object_unref (bus);
gst_plugin_feature_list_free (list);
g_slist_foreach (errors, (GFunc) gst_mini_object_unref, NULL);
g_slist_free (errors);
return choice;
}
static gboolean
gst_auto_audio_sink_detect (GstAutoAudioSink * sink)
{
GstElement *esink;
GstPad *targetpad;
if (sink->kid) {
gst_element_set_state (sink->kid, GST_STATE_NULL);
gst_bin_remove (GST_BIN (sink), sink->kid);
sink->kid = NULL;
}
/* find element */
GST_DEBUG_OBJECT (sink, "Creating new kid");
if (!(esink = gst_auto_audio_sink_find_best (sink))) {
return FALSE;
}
sink->kid = esink;
gst_element_set_state (sink->kid, GST_STATE (sink));
gst_bin_add (GST_BIN (sink), esink);
/* attach ghost pad */
GST_DEBUG_OBJECT (sink, "Re-assigning ghostpad");
targetpad = gst_element_get_pad (sink->kid, "sink");
gst_ghost_pad_set_target (GST_GHOST_PAD (sink->pad), targetpad);
gst_object_unref (targetpad);
GST_DEBUG_OBJECT (sink, "done changing auto audio sink");
return TRUE;
}
static GstStateChangeReturn
gst_auto_audio_sink_change_state (GstElement * element,
GstStateChange transition)
{
GstStateChangeReturn ret = GST_STATE_CHANGE_SUCCESS;
GstAutoAudioSink *sink = GST_AUTO_AUDIO_SINK (element);
switch (transition) {
case GST_STATE_CHANGE_NULL_TO_READY:
if (!gst_auto_audio_sink_detect (sink))
return GST_STATE_CHANGE_FAILURE;
break;
default:
break;
}
ret = GST_ELEMENT_CLASS (parent_class)->change_state (element, transition);
if (ret == GST_STATE_CHANGE_FAILURE)
return ret;
switch (transition) {
case GST_STATE_CHANGE_READY_TO_NULL:
gst_auto_audio_sink_reset (sink);
break;
default:
break;
}
return ret;
}