gstreamer/gst-libs/gst/propertyprobe/propertyprobe.c
David Schleef 06fdc56290 First attempt (actually third) at a property probing interface
Original commit message from CVS:
First attempt (actually third) at a property probing interface
2003-10-30 02:32:00 +00:00

176 lines
4.4 KiB
C

/* GStreamer PropertyProbe
* Copyright (C) 2003 David Schleef <ds@schleef.org>
*
* property_probe.c: property_probe design virtual class function wrappers
*
* 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.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gst/propertyprobe/propertyprobe.h>
static void gst_property_probe_iface_init (GstPropertyProbeInterface *iface);
enum {
NEED_PROBE,
LAST_SIGNAL
};
static guint gst_property_probe_signals[LAST_SIGNAL] = { 0 };
GType
gst_property_probe_get_type (void)
{
static GType gst_property_probe_type = 0;
if (!gst_property_probe_type) {
static const GTypeInfo gst_property_probe_info = {
sizeof (GstPropertyProbeInterface),
(GBaseInitFunc) gst_property_probe_iface_init,
NULL,
NULL,
NULL,
NULL,
0,
0,
NULL,
};
gst_property_probe_type = g_type_register_static (G_TYPE_INTERFACE,
"GstPropertyProbe",
&gst_property_probe_info, 0);
g_type_interface_add_prerequisite (gst_property_probe_type, G_TYPE_OBJECT);
}
return gst_property_probe_type;
}
static void
gst_property_probe_iface_init (GstPropertyProbeInterface *iface)
{
static gboolean initialized = FALSE;
if (!initialized) {
gst_property_probe_signals[NEED_PROBE] =
g_signal_new ("need_probe",
GST_TYPE_PROPERTY_PROBE,
G_SIGNAL_RUN_LAST,
G_STRUCT_OFFSET (GstPropertyProbeInterface, need_probe),
NULL,
NULL,
gst_marshal_VOID__STRING,
G_TYPE_NONE, 1,
G_TYPE_STRING);
initialized = TRUE;
}
/* default virtual functions */
iface->get_list = NULL;
iface->probe_property = NULL;
iface->get_property_info = NULL;
iface->is_probed = NULL;
}
char **
gst_property_probe_get_list (GstElement *element)
{
GstPropertyProbeInterface *iface;
g_return_val_if_fail (GST_IS_PROPERTY_PROBE (element), NULL);
iface = GST_PROPERTY_PROBE_GET_IFACE (element);
if (iface->get_list) {
return iface->get_list (element);
}
return NULL;
}
void
gst_property_probe_probe_property (GstElement *element,
const char *property)
{
GstPropertyProbeInterface *iface;
GParamSpec *ps;
g_return_if_fail (GST_IS_PROPERTY_PROBE (element));
g_return_if_fail (GST_STATE (element) == GST_STATE_NULL);
ps = g_object_class_find_property (G_OBJECT_CLASS (element), property);
if (ps == NULL) return;
iface = GST_PROPERTY_PROBE_GET_IFACE (element);
if (iface->probe_property) {
iface->probe_property (element, ps);
}
}
gchar **
gst_property_probe_get_property_info (GstElement *element,
const gchar *property)
{
GstPropertyProbeInterface *iface;
GParamSpec *ps;
g_return_val_if_fail (GST_IS_PROPERTY_PROBE (element), NULL);
ps = g_object_class_find_property (G_OBJECT_CLASS (element), property);
if (ps == NULL) return NULL;
iface = GST_PROPERTY_PROBE_GET_IFACE (element);
if (iface->get_property_info) {
return iface->get_property_info (element, ps);
}
return NULL;
}
gboolean
gst_property_probe_is_probed (GstElement *element,
const char *property)
{
GstPropertyProbeInterface *iface;
GParamSpec *ps;
g_return_val_if_fail (GST_IS_PROPERTY_PROBE (element), FALSE);
ps = g_object_class_find_property (G_OBJECT_CLASS (element), property);
if (ps == NULL) return FALSE;
iface = GST_PROPERTY_PROBE_GET_IFACE (element);
if (iface->is_probed) {
return iface->is_probed (element, ps);
}
return FALSE;
}
gchar **
gst_property_probe_get_possibilities (GstElement *element,
const char *property)
{
g_return_val_if_fail (GST_IS_PROPERTY_PROBE (element), NULL);
if (!gst_property_probe_is_probed (element, property)){
gst_property_probe_probe_property (element, property);
}
return gst_property_probe_get_property_info (element, property);
}