1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
|
/* GStreamer
* Copyright (C) 2015 Jan Schmidt <jan@centricular.com>
*
* gstdynamictypefactory.c: Implementation of GstDynamicTypeFactory
*
* 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:gstdynamictypefactory
* @title: GstDynamicTypeFactory
* @short_description: Represents a registered dynamically loadable GType
* @see_also: #GstPlugin, #GstPluginFeature.
*
* #GstDynamicTypeFactory is used to represent a type that can be
* automatically loaded the first time it is used. For example,
* a non-standard type for use in caps fields.
*
* In general, applications and plugins don't need to use the factory
* beyond registering the type in a plugin init function. Once that is
* done, the type is stored in the registry, and ready as soon as the
* registry is loaded.
*
* ## Registering a type for dynamic loading
*
* |[<!-- language="C" -->
*
* static gboolean
* plugin_init (GstPlugin * plugin)
* {
* return gst_dynamic_type_register (plugin, GST_TYPE_CUSTOM_CAPS_FIELD);
* }
* ]|
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "gst_private.h"
#include <glib-object.h>
#include "gst.h"
#include "glib-compat-private.h"
GST_DEBUG_CATEGORY_STATIC (dynamic_type_factory_debug);
#define GST_CAT_DEFAULT dynamic_type_factory_debug
#define _do_init \
{ \
GST_DEBUG_CATEGORY_INIT (dynamic_type_factory_debug, \
"GST_DYNAMIC_TYPE_FACTORY", GST_DEBUG_BOLD, \
"dynamic type factories allow automatically loading a type from a plugin"); \
}
G_DEFINE_TYPE_WITH_CODE (GstDynamicTypeFactory, gst_dynamic_type_factory,
GST_TYPE_PLUGIN_FEATURE, _do_init);
static void
gst_dynamic_type_factory_class_init (GstDynamicTypeFactoryClass * klass)
{
}
static void
gst_dynamic_type_factory_init (GstDynamicTypeFactory * factory)
{
}
static GstDynamicTypeFactory *
gst_dynamic_type_factory_find (const gchar * name)
{
GstPluginFeature *feature;
g_return_val_if_fail (name != NULL, NULL);
feature = gst_registry_find_feature (gst_registry_get (), name,
GST_TYPE_DYNAMIC_TYPE_FACTORY);
if (feature)
return GST_DYNAMIC_TYPE_FACTORY (feature);
return NULL;
}
GType
gst_dynamic_type_factory_load (const gchar * factoryname)
{
GstDynamicTypeFactory *factory = gst_dynamic_type_factory_find (factoryname);
/* Called with a non-dynamic or unregistered type? */
if (factory == NULL)
return FALSE;
factory =
GST_DYNAMIC_TYPE_FACTORY (gst_plugin_feature_load (GST_PLUGIN_FEATURE
(factory)));
if (factory == NULL)
return 0;
GST_DEBUG_OBJECT (factory, "Loaded type %s", factoryname);
return factory->type;
}
static GstDynamicTypeFactory *
gst_dynamic_type_factory_create (GstRegistry * registry,
GstPlugin * plugin, const gchar * name)
{
GstDynamicTypeFactory *factory;
factory = g_object_new (GST_TYPE_DYNAMIC_TYPE_FACTORY, NULL);
gst_plugin_feature_set_name (GST_PLUGIN_FEATURE_CAST (factory), name);
GST_LOG_OBJECT (factory, "Created new dynamictypefactory for type %s", name);
if (plugin && plugin->desc.name) {
GST_PLUGIN_FEATURE_CAST (factory)->plugin_name = plugin->desc.name;
GST_PLUGIN_FEATURE_CAST (factory)->plugin = plugin;
g_object_add_weak_pointer ((GObject *) plugin,
(gpointer *) & GST_PLUGIN_FEATURE_CAST (factory)->plugin);
} else {
GST_PLUGIN_FEATURE_CAST (factory)->plugin_name = "NULL";
GST_PLUGIN_FEATURE_CAST (factory)->plugin = NULL;
}
GST_PLUGIN_FEATURE_CAST (factory)->loaded = TRUE;
return factory;
}
gboolean
gst_dynamic_type_register (GstPlugin * plugin, GType dyn_type)
{
GstDynamicTypeFactory *factory;
const gchar *name;
GstPluginFeature *existing_feature;
GstRegistry *registry;
name = g_type_name (dyn_type);
g_return_val_if_fail (name != NULL, FALSE);
registry = gst_registry_get ();
/* check if feature already exists, if it exists there is no need to
* update it for this method of dynamic type */
existing_feature = gst_registry_lookup_feature (registry, name);
if (existing_feature) {
GST_DEBUG_OBJECT (registry, "update existing feature %p (%s)",
existing_feature, name);
existing_feature->loaded = TRUE;
GST_DYNAMIC_TYPE_FACTORY (existing_feature)->type = dyn_type;
gst_object_unref (existing_feature);
return TRUE;
}
factory = gst_dynamic_type_factory_create (registry, plugin, name);
factory->type = dyn_type;
gst_registry_add_feature (registry, GST_PLUGIN_FEATURE_CAST (factory));
return TRUE;
}
|
