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/gsttypes.h>
30 #include <gst/gstobject.h>
31 #include <gst/gstpad.h>
32 #include <gst/cothreads.h>
33 #include <gst/gstpluginfeature.h>
37 #endif /* __cplusplus */
39 #define GST_NUM_STATES 4
41 //typedef enum _GstElementState GstElementState;
42 //typedef enum _GstElementStateReturn GstElementStateReturn;
45 enum _GstElementState {
46 GST_STATE_VOID_PENDING = 0,
47 GST_STATE_NULL = (1 << 0),
48 GST_STATE_READY = (1 << 1),
49 GST_STATE_PAUSED = (1 << 2),
50 GST_STATE_PLAYING = (1 << 3),
53 enum _GstElementStateReturn {
54 GST_STATE_FAILURE = 0,
55 GST_STATE_SUCCESS = 1,
59 /* NOTE: this probably should be done with an #ifdef to decide
60 * whether to safe-cast or to just do the non-checking cast.
62 #define GST_STATE(obj) (GST_ELEMENT(obj)->current_state)
63 #define GST_STATE_PENDING(obj) (GST_ELEMENT(obj)->pending_state)
65 /* Note: using 8 bit shift mostly "just because", it leaves us enough room to grow <g> */
66 #define GST_STATE_TRANSITION(obj) ((GST_STATE(obj)<<8) | GST_STATE_PENDING(obj))
67 #define GST_STATE_NULL_TO_READY ((GST_STATE_NULL<<8) | GST_STATE_READY)
68 #define GST_STATE_READY_TO_PAUSED ((GST_STATE_READY<<8) | GST_STATE_PAUSED)
69 #define GST_STATE_PAUSED_TO_PLAYING ((GST_STATE_PAUSED<<8) | GST_STATE_PLAYING)
70 #define GST_STATE_PLAYING_TO_PAUSED ((GST_STATE_PLAYING<<8) | GST_STATE_PAUSED)
71 #define GST_STATE_PAUSED_TO_READY ((GST_STATE_PAUSED<<8) | GST_STATE_READY)
72 #define GST_STATE_READY_TO_NULL ((GST_STATE_READY<<8) | GST_STATE_NULL)
74 extern GType _gst_element_type;
76 #define GST_TYPE_ELEMENT (_gst_element_type)
78 #define GST_ELEMENT_FAST(obj) ((GstElement*)(obj))
79 #define GST_ELEMENT_CLASS_FAST(klass) ((GstElementClass*)(klass))
80 #define GST_IS_ELEMENT(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_ELEMENT))
81 #define GST_IS_ELEMENT_CLASS(obj) (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_ELEMENT))
83 #ifdef GST_TYPE_PARANOID
84 # define GST_ELEMENT(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_ELEMENT, GstElement))
85 # define GST_ELEMENT_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_ELEMENT, GstElementClass))
87 # define GST_ELEMENT GST_ELEMENT_FAST
88 # define GST_ELEMENT_CLASS GST_ELEMENT_CLASS_FAST
92 /* element is complex (for some def.) and generally require a cothread */
93 GST_ELEMENT_COMPLEX = GST_OBJECT_FLAG_LAST,
94 /* input and output pads aren't directly coupled to each other
95 examples: queues, multi-output async readers, etc. */
96 GST_ELEMENT_DECOUPLED,
97 /* this element should be placed in a thread if at all possible */
98 GST_ELEMENT_THREAD_SUGGESTED,
99 /* this element is incable of seeking (FIXME: does this apply to filters?) */
102 /***** !!!!! need to have a flag that says that an element must
103 *not* be an entry into a scheduling chain !!!!! *****/
104 /* this element for some reason doesn't obey COTHREAD_STOPPING, or
105 has some other reason why it can't be the entry */
106 GST_ELEMENT_NO_ENTRY,
108 /* there is a new loopfunction ready for placement */
109 GST_ELEMENT_NEW_LOOPFUNC,
110 /* the cothread holding this element needs to be stopped */
111 GST_ELEMENT_COTHREAD_STOPPING,
112 /* the element has to be scheduled as a cothread for any sanity */
113 GST_ELEMENT_USE_COTHREAD,
115 /* if this element can handle events */
116 GST_ELEMENT_EVENT_AWARE,
118 /* use some padding for future expansion */
119 GST_ELEMENT_FLAG_LAST = GST_OBJECT_FLAG_LAST + 12,
122 #define GST_ELEMENT_IS_THREAD_SUGGESTED(obj) (GST_FLAG_IS_SET(obj,GST_ELEMENT_THREAD_SUGGESTED))
123 #define GST_ELEMENT_IS_COTHREAD_STOPPING(obj) (GST_FLAG_IS_SET(obj,GST_ELEMENT_COTHREAD_STOPPING))
124 #define GST_ELEMENT_IS_EOS(obj) (GST_FLAG_IS_SET(obj,GST_ELEMENT_EOS))
125 #define GST_ELEMENT_IS_EVENT_AWARE(obj) (GST_FLAG_IS_SET(obj,GST_ELEMENT_EVENT_AWARE))
127 #define GST_ELEMENT_NAME(obj) (GST_OBJECT_NAME(obj))
128 #define GST_ELEMENT_PARENT(obj) (GST_OBJECT_PARENT(obj))
129 #define GST_ELEMENT_MANAGER(obj) (((GstElement*)(obj))->manager)
130 #define GST_ELEMENT_SCHED(obj) (((GstElement*)(obj))->sched)
131 #define GST_ELEMENT_PADS(obj) ((obj)->pads)
133 /*typedef struct _GstElement GstElement;*/
134 /*typedef struct _GstElementClass GstElementClass;*/
135 typedef struct _GstElementFactory GstElementFactory;
136 typedef struct _GstElementFactoryClass GstElementFactoryClass;
138 typedef void (*GstElementLoopFunction) (GstElement *element);
143 /* element state and scheduling */
144 guint8 current_state;
145 guint8 pending_state;
148 GstElementLoopFunction loopfunc;
149 cothread_state *threadstate;
162 struct _GstElementClass {
163 GstObjectClass parent_class;
165 /* the elementfactory that created us */
166 GstElementFactory *elementfactory;
167 /* templates for our pads */
169 gint numpadtemplates;
171 /* signal callbacks */
172 void (*state_change) (GstElement *element, GstElementState old, GstElementState state);
173 void (*new_pad) (GstElement *element, GstPad *pad);
174 void (*pad_removed) (GstElement *element, GstPad *pad);
175 void (*error) (GstElement *element, gchar *error);
176 void (*event) (GstElement *element, GstEvent *event);
177 void (*eos) (GstElement *element);
179 /* local pointers for get/set */
180 void (*set_property) (GObject *object, guint prop_id, const GValue *value, GParamSpec *pspec);
181 void (*get_property) (GObject *object, guint prop_id, GValue *value, GParamSpec *pspec);
184 /* change the element state */
185 GstElementStateReturn (*change_state) (GstElement *element);
186 /* request a new pad */
187 GstPad* (*request_new_pad) (GstElement *element, GstPadTemplate *templ, const gchar* name);
188 void (*send_event) (GstElement *element, GstEvent *event);
191 void gst_element_class_add_padtemplate (GstElementClass *klass, GstPadTemplate *templ);
193 GType gst_element_get_type (void);
194 #define gst_element_destroy(element) gst_object_destroy (GST_OBJECT (element))
196 void gst_element_set_loop_function (GstElement *element,
197 GstElementLoopFunction loop);
199 void gst_element_set_name (GstElement *element, const gchar *name);
200 const gchar* gst_element_get_name (GstElement *element);
202 void gst_element_set_parent (GstElement *element, GstObject *parent);
203 GstObject* gst_element_get_parent (GstElement *element);
205 void gst_element_set_sched (GstElement *element, GstScheduler *sched);
206 GstScheduler* gst_element_get_sched (GstElement *element);
208 void gst_element_add_pad (GstElement *element, GstPad *pad);
209 void gst_element_remove_pad (GstElement *element, GstPad *pad);
210 GstPad* gst_element_get_pad (GstElement *element, const gchar *name);
211 GList* gst_element_get_pad_list (GstElement *element);
212 GList* gst_element_get_padtemplate_list (GstElement *element);
213 GstPadTemplate* gst_element_get_padtemplate_by_name (GstElement *element, const guchar *name);
214 void gst_element_add_ghost_pad (GstElement *element, GstPad *pad, gchar *name);
215 void gst_element_remove_ghost_pad (GstElement *element, GstPad *pad);
217 GstPad* gst_element_request_compatible_pad (GstElement *element, GstPadTemplate *templ);
218 GstPad* gst_element_request_pad_by_name (GstElement *element, const gchar *name);
220 void gst_element_connect (GstElement *src, const gchar *srcpadname,
221 GstElement *dest, const gchar *destpadname);
222 void gst_element_disconnect (GstElement *src, const gchar *srcpadname,
223 GstElement *dest, const gchar *destpadname);
225 void gst_element_signal_eos (GstElement *element);
227 void gst_element_send_event (GstElement *element, GstEvent *event);
230 GstElementState gst_element_get_state (GstElement *element);
231 gint gst_element_set_state (GstElement *element, GstElementState state);
233 void gst_element_wait_state_change (GstElement *element);
235 const gchar* gst_element_statename (GstElementState state);
237 void gst_element_info (GstElement *element, const gchar *info, ...);
238 void gst_element_error (GstElement *element, const gchar *error, ...);
240 GstElementFactory* gst_element_get_factory (GstElement *element);
242 void gst_element_install_std_props (GstElementClass *klass,
243 const char *first_name, ...);
246 #ifndef GST_DISABLE_LOADSAVE
247 /* XML write and read */
248 GstElement* gst_element_restore_thyself (xmlNodePtr self, GstObject *parent);
257 typedef struct _GstElementDetails GstElementDetails;
259 struct _GstElementDetails {
260 gchar *longname; /* long, english name */
261 gchar *klass; /* type of element, as hierarchy */
262 gchar *description; /* insights of one form or another */
263 gchar *version; /* version of the element */
264 gchar *author; /* who wrote this thing? */
265 gchar *copyright; /* copyright details (year, etc.) */
268 #define GST_TYPE_ELEMENTFACTORY (gst_elementfactory_get_type())
269 #define GST_ELEMENTFACTORY(obj) (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_ELEMENTFACTORY,\
271 #define GST_ELEMENTFACTORY_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_ELEMENTFACTORY,\
272 GstElementFactoryClass))
273 #define GST_IS_ELEMENTFACTORY(obj) (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_ELEMENTFACTORY))
274 #define GST_IS_ELEMENTFACTORY_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_ELEMENTFACTORY))
276 struct _GstElementFactory {
277 GstPluginFeature feature;
279 GType type; /* unique GType of element */
281 guint details_dynamic : 1;
283 GstElementDetails *details; /* pointer to details struct */
286 guint16 numpadtemplates;
289 struct _GstElementFactoryClass {
290 GstPluginFeatureClass parent_class;
293 GType gst_elementfactory_get_type (void);
295 GstElementFactory* gst_elementfactory_new (const gchar *name,GType type,
296 GstElementDetails *details);
298 GstElementFactory* gst_elementfactory_find (const gchar *name);
299 const GList* gst_elementfactory_get_list (void);
301 void gst_elementfactory_add_padtemplate (GstElementFactory *elementfactory,
302 GstPadTemplate *templ);
304 gboolean gst_elementfactory_can_src_caps (GstElementFactory *factory,
306 gboolean gst_elementfactory_can_sink_caps (GstElementFactory *factory,
309 GstElement* gst_elementfactory_create (GstElementFactory *factory,
311 /* FIXME this name is wrong, probably so is the one above it */
312 GstElement* gst_elementfactory_make (const gchar *factoryname, const gchar *name);
316 #endif /* __cplusplus */
319 #endif /* __GST_ELEMENT_H__ */