2 * Copyright (C) 2004 Wim Taymans <wim@fluendo.com>
4 * gstmessage.h: Header for GstMessage subsystem
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Library General Public
8 * License as published by the Free Software Foundation; either
9 * version 2 of the License, or (at your option) any later version.
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Library General Public License for more details.
16 * You should have received a copy of the GNU Library General Public
17 * License along with this library; if not, write to the
18 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
19 * Boston, MA 02111-1307, USA.
22 #ifndef __GST_MESSAGE_H__
23 #define __GST_MESSAGE_H__
27 typedef struct _GstMessage GstMessage;
28 typedef struct _GstMessageClass GstMessageClass;
32 * @GST_MESSAGE_UNKNOWN: an undefined message
33 * @GST_MESSAGE_EOS: end-of-stream reached in a pipeline. The application will
34 * only receive this message in the PLAYING state and every time it sets a
35 * pipeline to PLAYING that is in the EOS state. The application can perform a
36 * flushing seek in the pipeline, which will undo the EOS state again.
37 * @GST_MESSAGE_ERROR: an error occured. Whe the application receives an error
38 * message it should stop playback of the pipeline and not assume that more
39 * data will be played.
40 * @GST_MESSAGE_WARNING: a warning occured.
41 * @GST_MESSAGE_INFO: an info message occured
42 * @GST_MESSAGE_TAG: a tag was found.
43 * @GST_MESSAGE_BUFFERING: the pipeline is buffering. When the application
44 * receives a buffering message in the PLAYING state for a non-live pipeline it
45 * must PAUSE the pipeline until the buffering completes, when the percentage
46 * field in the message is 100%. For live pipelines, no action must be
47 * performed and the buffering percentage can be used to inform the user about
49 * @GST_MESSAGE_STATE_CHANGED: a state change happened
50 * @GST_MESSAGE_STATE_DIRTY: an element changed state in a streaming thread.
51 * This message is deprecated.
52 * @GST_MESSAGE_STEP_DONE: a framestep finished. This message is not yet
54 * @GST_MESSAGE_CLOCK_PROVIDE: an element notifies its capability of providing
55 * a clock. This message is used internally and
56 * never forwarded to the application.
57 * @GST_MESSAGE_CLOCK_LOST: The current clock as selected by the pipeline became
58 * unusable. The pipeline will select a new clock on
59 * the next PLAYING state change.
60 * @GST_MESSAGE_NEW_CLOCK: a new clock was selected in the pipeline.
61 * @GST_MESSAGE_STRUCTURE_CHANGE: the structure of the pipeline changed. This
62 * message is used internally and never forwarded to the application.
63 * @GST_MESSAGE_STREAM_STATUS: status about a stream, emitted when it starts,
64 * stops, errors, etc.. Not implemented yet.
65 * @GST_MESSAGE_APPLICATION: message posted by the application, possibly
66 * via an application-specific element.
67 * @GST_MESSAGE_ELEMENT: element-specific message, see the specific element's
69 * @GST_MESSAGE_SEGMENT_START: pipeline started playback of a segment. This
70 * message is used internally and never forwarded to the application.
71 * @GST_MESSAGE_SEGMENT_DONE: pipeline completed playback of a segment. This
72 * message is forwarded to the application after all elements that posted
73 * @GST_MESSAGE_SEGMENT_START posted a GST_MESSAGE_SEGMENT_DONE message.
74 * @GST_MESSAGE_DURATION: The duration of a pipeline changed. The application
75 * can get the new duration with a duration query.
76 * @GST_MESSAGE_ASYNC_START: Posted by elements when they start an ASYNC state
77 * change. This message is not forwarded to the application but is used
78 * internally. Since: 0.10.13.
79 * @GST_MESSAGE_ASYNC_DONE: Posted by elements when they complete an ASYNC state
80 * change. The application will only receive this message from the toplevel
81 * pipeline. Since: 0.10.13
82 * @GST_MESSAGE_LATENCY: Posted by elements when their latency changes. The
83 * pipeline will calculate and distribute a new latency. Since: 0.10.12
84 * @GST_MESSAGE_REQUEST_STATE: Posted by elements when they want the pipeline to
85 * change state. This message is a suggestion to the application which can
86 * decide to perform the state change on (part of) the pipeline. Since: 0.10.23.
87 * @GST_MESSAGE_ANY: mask for all of the above messages.
89 * The different message types that are available.
91 /* NOTE: keep in sync with quark registration in gstmessage.c
92 * NOTE: keep GST_MESSAGE_ANY a valid gint to avoid compiler warnings.
96 GST_MESSAGE_UNKNOWN = 0,
97 GST_MESSAGE_EOS = (1 << 0),
98 GST_MESSAGE_ERROR = (1 << 1),
99 GST_MESSAGE_WARNING = (1 << 2),
100 GST_MESSAGE_INFO = (1 << 3),
101 GST_MESSAGE_TAG = (1 << 4),
102 GST_MESSAGE_BUFFERING = (1 << 5),
103 GST_MESSAGE_STATE_CHANGED = (1 << 6),
104 GST_MESSAGE_STATE_DIRTY = (1 << 7),
105 GST_MESSAGE_STEP_DONE = (1 << 8),
106 GST_MESSAGE_CLOCK_PROVIDE = (1 << 9),
107 GST_MESSAGE_CLOCK_LOST = (1 << 10),
108 GST_MESSAGE_NEW_CLOCK = (1 << 11),
109 GST_MESSAGE_STRUCTURE_CHANGE = (1 << 12),
110 GST_MESSAGE_STREAM_STATUS = (1 << 13),
111 GST_MESSAGE_APPLICATION = (1 << 14),
112 GST_MESSAGE_ELEMENT = (1 << 15),
113 GST_MESSAGE_SEGMENT_START = (1 << 16),
114 GST_MESSAGE_SEGMENT_DONE = (1 << 17),
115 GST_MESSAGE_DURATION = (1 << 18),
116 GST_MESSAGE_LATENCY = (1 << 19),
117 GST_MESSAGE_ASYNC_START = (1 << 20),
118 GST_MESSAGE_ASYNC_DONE = (1 << 21),
119 GST_MESSAGE_REQUEST_STATE = (1 << 22),
123 #include <gst/gstminiobject.h>
124 #include <gst/gstobject.h>
125 #include <gst/gstelement.h>
126 #include <gst/gsttaglist.h>
127 #include <gst/gststructure.h>
130 * GST_MESSAGE_TRACE_NAME:
132 * The name used for memory allocation tracing
134 #define GST_MESSAGE_TRACE_NAME "GstMessage"
136 #define GST_TYPE_MESSAGE (gst_message_get_type())
137 #define GST_IS_MESSAGE(obj) (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_MESSAGE))
138 #define GST_IS_MESSAGE_CLASS(klass) (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_MESSAGE))
139 #define GST_MESSAGE_GET_CLASS(obj) (G_TYPE_INSTANCE_GET_CLASS ((obj), GST_TYPE_MESSAGE, GstMessageClass))
140 #define GST_MESSAGE(obj) (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_MESSAGE, GstMessage))
141 #define GST_MESSAGE_CLASS(klass) (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_MESSAGE, GstMessageClass))
142 #define GST_MESSAGE_CAST(obj) ((GstMessage*)(obj))
144 /* the lock is used to handle the synchronous handling of messages,
145 * the emiting thread is block until the handling thread processed
146 * the message using this mutex/cond pair */
147 #define GST_MESSAGE_GET_LOCK(message) (GST_MESSAGE(message)->lock)
148 #define GST_MESSAGE_LOCK(message) g_mutex_lock(GST_MESSAGE_GET_LOCK(message))
149 #define GST_MESSAGE_UNLOCK(message) g_mutex_unlock(GST_MESSAGE_GET_LOCK(message))
150 #define GST_MESSAGE_COND(message) (GST_MESSAGE(message)->cond)
151 #define GST_MESSAGE_WAIT(message) g_cond_wait(GST_MESSAGE_COND(message),GST_MESSAGE_GET_LOCK(message))
152 #define GST_MESSAGE_SIGNAL(message) g_cond_signal(GST_MESSAGE_COND(message))
156 * @message: a #GstMessage
158 * Get the #GstMessageType of @message.
160 #define GST_MESSAGE_TYPE(message) (GST_MESSAGE(message)->type)
162 * GST_MESSAGE_TYPE_NAME:
163 * @message: a #GstMessage
165 * Get a constant string representation of the #GstMessageType of @message.
169 #define GST_MESSAGE_TYPE_NAME(message) gst_message_type_get_name(GST_MESSAGE_TYPE(message))
171 * GST_MESSAGE_TIMESTAMP:
172 * @message: a #GstMessage
174 * Get the timestamp of @message. This is the timestamp when the message
177 #define GST_MESSAGE_TIMESTAMP(message) (GST_MESSAGE(message)->timestamp)
180 * @message: a #GstMessage
182 * Get the object that posted @message.
184 #define GST_MESSAGE_SRC(message) (GST_MESSAGE(message)->src)
187 * GstStructureChangeType:
188 * @GST_STRUCTURE_CHANGE_TYPE_PAD_LINK: Pad linking is starting or done.
189 * @GST_STRUCTURE_CHANGE_TYPE_PAD_UNLINK: Pad unlinking is starting or done.
191 * The type of a #GstMessageStructureChange.
196 GST_STRUCTURE_CHANGE_TYPE_PAD_LINK = 0,
197 GST_STRUCTURE_CHANGE_TYPE_PAD_UNLINK = 1
198 } GstStructureChangeType;
202 * @mini_object: the parent structure
203 * @type: the #GstMessageType of the message
204 * @timestamp: the timestamp of the message
205 * @src: the src of the message
206 * @structure: the #GstStructure containing the message info.
212 GstMiniObject mini_object;
214 /*< private > *//* with MESSAGE_LOCK */
215 GMutex *lock; /* lock and cond for async delivery */
218 /*< public > *//* with COW */
223 GstStructure *structure;
230 /* + 0 to mark ABI change for future greppage */
231 gpointer _gst_reserved[GST_PADDING + 0];
235 struct _GstMessageClass {
236 GstMiniObjectClass mini_object_class;
239 gpointer _gst_reserved[GST_PADDING];
242 GType gst_message_get_type (void);
244 const gchar* gst_message_type_get_name (GstMessageType type);
245 GQuark gst_message_type_to_quark (GstMessageType type);
250 * @msg: the message to ref
252 * Convenience macro to increase the reference count of the message.
254 * Returns: @msg (for convenience when doing assignments)
256 #ifdef _FOOL_GTK_DOC_
257 G_INLINE_FUNC GstMessage * gst_message_ref (GstMessage * msg);
260 static inline GstMessage *
261 gst_message_ref (GstMessage * msg)
263 /* not using a macro here because gcc-4.1 will complain
264 * if the return value isn't used (because of the cast) */
265 return (GstMessage *) gst_mini_object_ref (GST_MINI_OBJECT (msg));
270 * @msg: the message to unref
272 * Convenience macro to decrease the reference count of the message, possibly
275 #define gst_message_unref(msg) gst_mini_object_unref (GST_MINI_OBJECT (msg))
279 * @msg: the message to copy
281 * Creates a copy of the message. Returns a copy of the message.
285 #define gst_message_copy(msg) GST_MESSAGE (gst_mini_object_copy (GST_MINI_OBJECT (msg)))
287 * gst_message_make_writable:
288 * @msg: the message to make writable
290 * Checks if a message is writable. If not, a writable copy is made and
291 * returned. Returns a message (possibly a duplicate) that is writable.
295 #define gst_message_make_writable(msg) GST_MESSAGE (gst_mini_object_make_writable (GST_MINI_OBJECT (msg)))
297 /* identifiers for events and messages */
298 guint32 gst_message_get_seqnum (GstMessage *message);
299 void gst_message_set_seqnum (GstMessage *message, guint32 seqnum);
302 GstMessage * gst_message_new_eos (GstObject * src);
306 GstMessage * gst_message_new_error (GstObject * src, GError * error, const gchar * debug);
307 void gst_message_parse_error (GstMessage *message, GError **gerror, gchar **debug);
310 GstMessage * gst_message_new_warning (GstObject * src, GError * error, const gchar * debug);
311 void gst_message_parse_warning (GstMessage *message, GError **gerror, gchar **debug);
314 GstMessage * gst_message_new_info (GstObject * src, GError * error, const gchar * debug);
315 void gst_message_parse_info (GstMessage *message, GError **gerror, gchar **debug);
318 GstMessage * gst_message_new_tag (GstObject * src, GstTagList * tag_list);
319 void gst_message_parse_tag (GstMessage *message, GstTagList **tag_list);
322 GstMessage * gst_message_new_buffering (GstObject * src, gint percent);
323 void gst_message_parse_buffering (GstMessage *message, gint *percent);
324 void gst_message_set_buffering_stats (GstMessage *message, GstBufferingMode mode,
325 gint avg_in, gint avg_out,
326 gint64 buffering_left);
327 void gst_message_parse_buffering_stats (GstMessage *message, GstBufferingMode *mode,
328 gint *avg_in, gint *avg_out,
329 gint64 *buffering_left);
332 GstMessage * gst_message_new_state_changed (GstObject * src, GstState oldstate,
333 GstState newstate, GstState pending);
334 void gst_message_parse_state_changed (GstMessage *message, GstState *oldstate,
335 GstState *newstate, GstState *pending);
338 GstMessage * gst_message_new_state_dirty (GstObject * src);
341 GstMessage * gst_message_new_clock_provide (GstObject * src, GstClock *clock, gboolean ready);
342 void gst_message_parse_clock_provide (GstMessage *message, GstClock **clock,
346 GstMessage * gst_message_new_clock_lost (GstObject * src, GstClock *clock);
347 void gst_message_parse_clock_lost (GstMessage *message, GstClock **clock);
350 GstMessage * gst_message_new_new_clock (GstObject * src, GstClock *clock);
351 void gst_message_parse_new_clock (GstMessage *message, GstClock **clock);
354 GstMessage * gst_message_new_application (GstObject * src, GstStructure * structure);
357 GstMessage * gst_message_new_element (GstObject * src, GstStructure * structure);
360 GstMessage * gst_message_new_segment_start (GstObject * src, GstFormat format, gint64 position);
361 void gst_message_parse_segment_start (GstMessage *message, GstFormat *format,
365 GstMessage * gst_message_new_segment_done (GstObject * src, GstFormat format, gint64 position);
366 void gst_message_parse_segment_done (GstMessage *message, GstFormat *format,
370 GstMessage * gst_message_new_duration (GstObject * src, GstFormat format, gint64 duration);
371 void gst_message_parse_duration (GstMessage *message, GstFormat *format,
375 GstMessage * gst_message_new_latency (GstObject * src);
378 GstMessage * gst_message_new_async_start (GstObject * src, gboolean new_base_time);
379 void gst_message_parse_async_start (GstMessage *message, gboolean *new_base_time);
382 GstMessage * gst_message_new_async_done (GstObject * src);
384 /* STRUCTURE CHANGE */
385 GstMessage * gst_message_new_structure_change (GstObject * src, GstStructureChangeType type,
386 GstElement *owner, gboolean busy);
387 void gst_message_parse_structure_change (GstMessage *message, GstStructureChangeType *type,
388 GstElement **owner, gboolean *busy);
391 GstMessage * gst_message_new_request_state (GstObject * src, GstState state);
392 void gst_message_parse_request_state (GstMessage * message, GstState *state);
394 /* custom messages */
395 GstMessage * gst_message_new_custom (GstMessageType type,
397 GstStructure * structure);
398 const GstStructure * gst_message_get_structure (GstMessage *message);
402 #endif /* __GST_MESSAGE_H__ */