2 * Copyright (C) 1999,2000 Erik Walthinsen <omega@cse.ogi.edu>
3 * 2000 Wim Taymans <wtay@chello.be>
5 * gstelement.h: Header for GstElement
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Library General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Library General Public License for more details.
17 * You should have received a copy of the GNU Library General Public
18 * License along with this library; if not, write to the
19 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
20 * Boston, MA 02111-1307, USA.
24 #ifndef __GST_ELEMENT_H__
25 #define __GST_ELEMENT_H__
27 #include <gst/gstconfig.h>
29 #include <gst/gstobject.h>
30 #include <gst/gstpad.h>
31 #include <gst/cothreads.h>
32 #include <gst/gstpluginfeature.h>
36 #endif /* __cplusplus */
38 #define GST_NUM_STATES 4
41 GST_STATE_VOID_PENDING = 0,
42 GST_STATE_NULL = (1 << 0),
43 GST_STATE_READY = (1 << 1),
44 GST_STATE_PAUSED = (1 << 2),
45 GST_STATE_PLAYING = (1 << 3),
49 GST_STATE_FAILURE = 0,
50 GST_STATE_SUCCESS = 1,
52 } GstElementStateReturn;
55 // NOTE: this probably should be done with an #ifdef to decide whether to safe-cast
56 // or to just do the non-checking cast.
57 #define GST_STATE(obj) (GST_ELEMENT(obj)->current_state)
58 #define GST_STATE_PENDING(obj) (GST_ELEMENT(obj)->pending_state)
60 // Note: using 8 bit shift mostly "just because", it leaves us enough room to grow <g>
61 #define GST_STATE_TRANSITION(obj) ((GST_STATE(obj)<<8) | GST_STATE_PENDING(obj))
62 #define GST_STATE_NULL_TO_READY ((GST_STATE_NULL<<8) | GST_STATE_READY)
63 #define GST_STATE_READY_TO_PAUSED ((GST_STATE_READY<<8) | GST_STATE_PAUSED)
64 #define GST_STATE_PAUSED_TO_PLAYING ((GST_STATE_PAUSED<<8) | GST_STATE_PLAYING)
65 #define GST_STATE_PLAYING_TO_PAUSED ((GST_STATE_PLAYING<<8) | GST_STATE_PAUSED)
66 #define GST_STATE_PAUSED_TO_READY ((GST_STATE_PAUSED<<8) | GST_STATE_READY)
67 #define GST_STATE_READY_TO_NULL ((GST_STATE_READY<<8) | GST_STATE_NULL)
69 extern GType _gst_element_type;
71 #define GST_TYPE_ELEMENT (_gst_element_type)
73 #define GST_ELEMENT_FAST(obj) ((GstElement*)(obj))
74 #define GST_ELEMENT_CLASS_FAST(klass) ((GstElementClass*)(klass))
75 #define GST_IS_ELEMENT(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_ELEMENT))
76 #define GST_IS_ELEMENT_CLASS(obj) (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_ELEMENT))
78 #ifdef GST_TYPE_PARANOID
79 # define GST_ELEMENT(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_ELEMENT, GstElement))
80 # define GST_ELEMENT_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_ELEMENT, GstElementClass))
82 # define GST_ELEMENT GST_ELEMENT_FAST
83 # define GST_ELEMENT_CLASS GST_ELEMENT_CLASS_FAST
87 /* element is complex (for some def.) and generally require a cothread */
88 GST_ELEMENT_COMPLEX = GST_OBJECT_FLAG_LAST,
89 /* input and output pads aren't directly coupled to each other
90 examples: queues, multi-output async readers, etc. */
91 GST_ELEMENT_DECOUPLED,
92 /* this element should be placed in a thread if at all possible */
93 GST_ELEMENT_THREAD_SUGGESTED,
94 /* this element is incable of seeking (FIXME: does this apply to filters?) */
97 /***** !!!!! need to have a flag that says that an element must
98 *not* be an entry into a scheduling chain !!!!! *****/
99 /* this element for some reason doesn't obey COTHREAD_STOPPING, or
100 has some other reason why it can't be the entry */
101 GST_ELEMENT_NO_ENTRY,
103 /* there is a new loopfunction ready for placement */
104 GST_ELEMENT_NEW_LOOPFUNC,
105 /* the cothread holding this element needs to be stopped */
106 GST_ELEMENT_COTHREAD_STOPPING,
107 /* the element has to be scheduled as a cothread for any sanity */
108 GST_ELEMENT_USE_COTHREAD,
110 /* if this element can handle events */
111 GST_ELEMENT_EVENT_AWARE,
113 /* use some padding for future expansion */
114 GST_ELEMENT_FLAG_LAST = GST_OBJECT_FLAG_LAST + 12,
117 #define GST_ELEMENT_IS_THREAD_SUGGESTED(obj) (GST_FLAG_IS_SET(obj,GST_ELEMENT_THREAD_SUGGESTED))
118 #define GST_ELEMENT_IS_COTHREAD_STOPPING(obj) (GST_FLAG_IS_SET(obj,GST_ELEMENT_COTHREAD_STOPPING))
119 #define GST_ELEMENT_IS_EOS(obj) (GST_FLAG_IS_SET(obj,GST_ELEMENT_EOS))
120 #define GST_ELEMENT_IS_EVENT_AWARE(obj) (GST_FLAG_IS_SET(obj,GST_ELEMENT_EVENT_AWARE))
122 #define GST_ELEMENT_NAME(obj) (GST_OBJECT_NAME(obj))
123 #define GST_ELEMENT_PARENT(obj) (GST_OBJECT_PARENT(obj))
124 #define GST_ELEMENT_MANAGER(obj) (((GstElement*)(obj))->manager)
125 #define GST_ELEMENT_SCHED(obj) (((GstElement*)(obj))->sched)
126 #define GST_ELEMENT_PADS(obj) ((obj)->pads)
128 //typedef struct _GstElement GstElement;
129 //typedef struct _GstElementClass GstElementClass;
130 typedef struct _GstElementFactory GstElementFactory;
131 typedef struct _GstElementFactoryClass GstElementFactoryClass;
133 typedef void (*GstElementLoopFunction) (GstElement *element);
138 /* element state and scheduling */
139 guint8 current_state;
140 guint8 pending_state;
143 GstElementLoopFunction loopfunc;
144 cothread_state *threadstate;
154 struct _GstElementClass {
155 GstObjectClass parent_class;
157 /* the elementfactory that created us */
158 GstElementFactory *elementfactory;
159 /* templates for our pads */
161 gint numpadtemplates;
163 /* signal callbacks */
164 void (*state_change) (GstElement *element, GstElementState old, GstElementState state);
165 void (*new_pad) (GstElement *element, GstPad *pad);
166 void (*pad_removed) (GstElement *element, GstPad *pad);
167 void (*error) (GstElement *element, gchar *error);
168 void (*eos) (GstElement *element);
170 /* local pointers for get/set */
171 void (*set_property) (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec);
172 void (*get_property) (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec);
174 /* change the element state */
175 GstElementStateReturn (*change_state) (GstElement *element);
176 /* request a new pad */
177 GstPad* (*request_new_pad) (GstElement *element, GstPadTemplate *templ, const gchar* name);
180 void gst_element_class_add_padtemplate (GstElementClass *klass, GstPadTemplate *templ);
182 GType gst_element_get_type (void);
183 #define gst_element_destroy(element) gst_object_destroy (GST_OBJECT (element))
185 void gst_element_set_loop_function (GstElement *element,
186 GstElementLoopFunction loop);
188 void gst_element_set_name (GstElement *element, const gchar *name);
189 const gchar* gst_element_get_name (GstElement *element);
191 void gst_element_set_parent (GstElement *element, GstObject *parent);
192 GstObject* gst_element_get_parent (GstElement *element);
194 void gst_element_set_sched (GstElement *element, GstScheduler *sched);
195 GstScheduler* gst_element_get_sched (GstElement *element);
197 void gst_element_add_pad (GstElement *element, GstPad *pad);
198 void gst_element_remove_pad (GstElement *element, GstPad *pad);
199 GstPad* gst_element_get_pad (GstElement *element, const gchar *name);
200 GList* gst_element_get_pad_list (GstElement *element);
201 GList* gst_element_get_padtemplate_list (GstElement *element);
202 GstPadTemplate* gst_element_get_padtemplate_by_name (GstElement *element, const guchar *name);
203 void gst_element_add_ghost_pad (GstElement *element, GstPad *pad, gchar *name);
204 void gst_element_remove_ghost_pad (GstElement *element, GstPad *pad);
206 GstPad* gst_element_request_compatible_pad (GstElement *element, GstPadTemplate *templ);
207 GstPad* gst_element_request_pad_by_name (GstElement *element, const gchar *name);
209 void gst_element_connect (GstElement *src, const gchar *srcpadname,
210 GstElement *dest, const gchar *destpadname);
211 void gst_element_disconnect (GstElement *src, const gchar *srcpadname,
212 GstElement *dest, const gchar *destpadname);
214 void gst_element_signal_eos (GstElement *element);
217 GstElementState gst_element_get_state (GstElement *element);
218 gint gst_element_set_state (GstElement *element, GstElementState state);
220 void gst_element_wait_state_change (GstElement *element);
222 const gchar* gst_element_statename (GstElementState state);
224 void gst_element_error (GstElement *element, const gchar *error);
226 GstElementFactory* gst_element_get_factory (GstElement *element);
228 #ifndef GST_DISABLE_LOADSAVE
229 /* XML write and read */
230 GstElement* gst_element_restore_thyself (xmlNodePtr self, GstObject *parent);
239 typedef struct _GstElementDetails GstElementDetails;
241 struct _GstElementDetails {
242 gchar *longname; /* long, english name */
243 gchar *klass; /* type of element, as hierarchy */
244 gchar *description; /* insights of one form or another */
245 gchar *version; /* version of the element */
246 gchar *author; /* who wrote this thing? */
247 gchar *copyright; /* copyright details (year, etc.) */
250 #define GST_TYPE_ELEMENTFACTORY (gst_elementfactory_get_type())
251 #define GST_ELEMENTFACTORY(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_ELEMENTFACTORY,\
253 #define GST_ELEMENTFACTORY_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_ELEMENTFACTORY,\
254 GstElementFactoryClass))
255 #define GST_IS_ELEMENTFACTORY(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_ELEMENTFACTORY))
256 #define GST_IS_ELEMENTFACTORY_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_ELEMENTFACTORY))
258 struct _GstElementFactory {
259 GstPluginFeature feature;
261 GType type; /* unique GType of element */
263 guint details_dynamic : 1;
265 GstElementDetails *details; /* pointer to details struct */
268 guint16 numpadtemplates;
271 struct _GstElementFactoryClass {
272 GstPluginFeatureClass parent_class;
275 GType gst_elementfactory_get_type (void);
277 GstElementFactory* gst_elementfactory_new (const gchar *name,GType type,
278 GstElementDetails *details);
280 GstElementFactory* gst_elementfactory_find (const gchar *name);
281 const GList* gst_elementfactory_get_list (void);
283 void gst_elementfactory_add_padtemplate (GstElementFactory *elementfactory,
284 GstPadTemplate *templ);
286 gboolean gst_elementfactory_can_src_caps (GstElementFactory *factory,
288 gboolean gst_elementfactory_can_sink_caps (GstElementFactory *factory,
291 GstElement* gst_elementfactory_create (GstElementFactory *factory,
293 /* FIXME this name is wrong, probably so is the one above it */
294 GstElement* gst_elementfactory_make (const gchar *factoryname, const gchar *name);
299 #endif /* __cplusplus */
302 #endif /* __GST_ELEMENT_H__ */