From c186da6a66001e3de61d53212c708fd2e6cab5d2 Mon Sep 17 00:00:00 2001 From: David Schleef Date: Thu, 30 Oct 2003 02:32:00 +0000 Subject: First attempt (actually third) at a property probing interface Original commit message from CVS: First attempt (actually third) at a property probing interface --- gst-libs/gst/propertyprobe/propertyprobe.c | 176 +++++++++++++++++++++++++++++ 1 file changed, 176 insertions(+) create mode 100644 gst-libs/gst/propertyprobe/propertyprobe.c (limited to 'gst-libs/gst/propertyprobe/propertyprobe.c') diff --git a/gst-libs/gst/propertyprobe/propertyprobe.c b/gst-libs/gst/propertyprobe/propertyprobe.c new file mode 100644 index 00000000..f0cfe940 --- /dev/null +++ b/gst-libs/gst/propertyprobe/propertyprobe.c @@ -0,0 +1,176 @@ +/* GStreamer PropertyProbe + * Copyright (C) 2003 David Schleef + * + * 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 + +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); +} + -- cgit v1.2.1