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 <parser.h> // NOTE: this is xml-config's fault
29 // Include compatability defines: if libxml hasn't already defined these,
30 // we have an old version 1.x
31 #ifndef xmlChildrenNode
32 #define xmlChildrenNode childs
33 #define xmlRootNode root
36 #include <gst/gstobject.h>
37 #include <gst/gstpad.h>
38 #include <gst/cothreads.h>
42 #endif /* __cplusplus */
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),
54 GST_STATE_FAILURE = 0,
55 GST_STATE_SUCCESS = 1,
57 } GstElementStateReturn;
60 // NOTE: this probably should be done with an #ifdef to decide whether to safe-cast
61 // 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 #define GST_TYPE_ELEMENT \
75 (gst_element_get_type())
76 #define GST_ELEMENT(obj) \
77 (G_TYPE_CHECK_INSTANCE_CAST((obj),GST_TYPE_ELEMENT,GstElement))
78 #define GST_ELEMENT_CLASS(klass) \
79 (G_TYPE_CHECK_CLASS_CAST((klass),GST_TYPE_ELEMENT,GstElementClass))
80 #define GST_IS_ELEMENT(obj) \
81 (G_TYPE_CHECK_INSTANCE_TYPE((obj),GST_TYPE_ELEMENT))
82 #define GST_IS_ELEMENT_CLASS(klass) \
83 (G_TYPE_CHECK_CLASS_TYPE((klass),GST_TYPE_ELEMENT))
86 /* element is complex (for some def.) and generally require a cothread */
87 GST_ELEMENT_COMPLEX = GST_OBJECT_FLAG_LAST,
88 /* input and output pads aren't directly coupled to each other
89 examples: queues, multi-output async readers, etc. */
90 GST_ELEMENT_DECOUPLED,
91 /* this element should be placed in a thread if at all possible */
92 GST_ELEMENT_THREAD_SUGGESTED,
93 /* this element is incable of seeking (FIXME: does this apply to filters?) */
96 /***** !!!!! need to have a flag that says that an element must
97 *not* be an entry into a scheduling chain !!!!! *****/
98 /* this element for some reason doesn't obey COTHREAD_STOPPING, or
99 has some other reason why it can't be the entry */
100 GST_ELEMENT_NO_ENTRY,
102 /* there is a new loopfunction ready for placement */
103 GST_ELEMENT_NEW_LOOPFUNC,
104 /* the cothread holding this element needs to be stopped */
105 GST_ELEMENT_COTHREAD_STOPPING,
106 /* the element has to be scheduled as a cothread for any sanity */
107 GST_ELEMENT_USE_COTHREAD,
109 /* if this element is in EOS */
112 /* use some padding for future expansion */
113 GST_ELEMENT_FLAG_LAST = GST_OBJECT_FLAG_LAST + 12,
116 #define GST_ELEMENT_IS_THREAD_SUGGESTED(obj) (GST_FLAG_IS_SET(obj,GST_ELEMENT_THREAD_SUGGESTED))
117 #define GST_ELEMENT_IS_COTHREAD_STOPPING(obj) (GST_FLAG_IS_SET(obj,GST_ELEMENT_COTHREAD_STOPPING))
118 #define GST_ELEMENT_IS_EOS(obj) (GST_FLAG_IS_SET(obj,GST_ELEMENT_EOS))
120 #define GST_ELEMENT_NAME(obj) (GST_OBJECT_NAME(obj))
121 #define GST_ELEMENT_PARENT(obj) (GST_OBJECT_PARENT(obj))
122 #define GST_ELEMENT_MANAGER(obj) (((GstElement*)(obj))->manager)
123 #define GST_ELEMENT_SCHED(obj) (((GstElement*)(obj))->sched)
124 #define GST_ELEMENT_PADS(obj) ((obj)->pads)
126 //typedef struct _GstElement GstElement;
127 //typedef struct _GstElementClass GstElementClass;
128 typedef struct _GstElementDetails GstElementDetails;
129 typedef struct _GstElementFactory GstElementFactory;
131 typedef void (*GstElementLoopFunction) (GstElement *element);
136 guint8 current_state;
137 guint8 pending_state;
139 GstElementLoopFunction loopfunc;
140 cothread_state *threadstate;
152 struct _GstElementClass {
153 GstObjectClass parent_class;
155 /* the elementfactory that created us */
156 GstElementFactory *elementfactory;
157 /* templates for our pads */
159 gint numpadtemplates;
161 /* signal callbacks */
162 void (*state_change) (GstElement *element,GstElementState state);
163 void (*new_pad) (GstElement *element,GstPad *pad);
164 void (*pad_removed) (GstElement *element,GstPad *pad);
165 void (*new_ghost_pad) (GstElement *element,GstPad *pad);
166 void (*ghost_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, const 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);
180 struct _GstElementDetails {
181 gchar *longname; /* long, english name */
182 gchar *klass; /* type of element, as hierarchy */
183 gchar *description; /* insights of one form or another */
184 gchar *version; /* version of the element */
185 gchar *author; /* who wrote this thing? */
186 gchar *copyright; /* copyright details (year, etc.) */
189 struct _GstElementFactory {
190 gchar *name; /* name of element */
191 GType type; /* unique GType of element */
193 GstElementDetails *details; /* pointer to details struct */
196 guint16 numpadtemplates;
199 void gst_element_class_add_padtemplate (GstElementClass *element, GstPadTemplate *templ);
201 GType gst_element_get_type (void);
202 GstElement* gst_element_new (void);
203 #define gst_element_destroy(element) gst_object_destroy (GST_OBJECT (element))
205 void gst_element_set_loop_function (GstElement *element,
206 GstElementLoopFunction loop);
208 void gst_element_set_name (GstElement *element, const gchar *name);
209 const gchar* gst_element_get_name (GstElement *element);
211 void gst_element_set_parent (GstElement *element, GstObject *parent);
212 GstObject* gst_element_get_parent (GstElement *element);
214 void gst_element_set_sched (GstElement *element, GstSchedule *sched);
215 GstSchedule* gst_element_get_sched (GstElement *element);
217 void gst_element_add_pad (GstElement *element, GstPad *pad);
218 void gst_element_remove_pad (GstElement *element, GstPad *pad);
219 GstPad* gst_element_get_pad (GstElement *element, const gchar *name);
220 GList* gst_element_get_pad_list (GstElement *element);
221 GList* gst_element_get_padtemplate_list (GstElement *element);
222 GstPadTemplate* gst_element_get_padtemplate_by_name (GstElement *element, const guchar *name);
223 void gst_element_add_ghost_pad (GstElement *element, GstPad *pad, gchar *name);
224 void gst_element_remove_ghost_pad (GstElement *element, GstPad *pad);
226 GstPad* gst_element_request_compatible_pad (GstElement *element, GstPadTemplate *templ);
227 GstPad* gst_element_request_pad_by_name (GstElement *element, const gchar *name);
229 void gst_element_connect (GstElement *src, const gchar *srcpadname,
230 GstElement *dest, const gchar *destpadname);
231 void gst_element_disconnect (GstElement *src, const gchar *srcpadname,
232 GstElement *dest, const gchar *destpadname);
234 void gst_element_signal_eos (GstElement *element);
237 /* called by the app to set the state of the element */
238 gint gst_element_set_state (GstElement *element, GstElementState state);
240 void gst_element_error (GstElement *element, const gchar *error);
242 GstElementFactory* gst_element_get_factory (GstElement *element);
244 /* XML write and read */
245 GstElement* gst_element_restore_thyself (xmlNodePtr self, GstObject *parent);
253 GstElementFactory* gst_elementfactory_new (const gchar *name,GType type,
254 GstElementDetails *details);
255 void gst_elementfactory_destroy (GstElementFactory *elementfactory);
257 GstElementFactory* gst_elementfactory_find (const gchar *name);
258 GList* gst_elementfactory_get_list (void);
260 void gst_elementfactory_add_padtemplate (GstElementFactory *elementfactory,
261 GstPadTemplate *templ);
263 gboolean gst_elementfactory_can_src_caps (GstElementFactory *factory,
265 gboolean gst_elementfactory_can_sink_caps (GstElementFactory *factory,
268 GstElement* gst_elementfactory_create (GstElementFactory *factory,
270 /* FIXME this name is wrong, probably so is the one above it */
271 GstElement* gst_elementfactory_make (const gchar *factoryname, const gchar *name);
274 xmlNodePtr gst_elementfactory_save_thyself (GstElementFactory *factory, xmlNodePtr parent);
275 GstElementFactory* gst_elementfactory_load_thyself (xmlNodePtr parent);
278 const gchar * gst_element_statename (int state);
282 #endif /* __cplusplus */
285 #endif /* __GST_ELEMENT_H__ */