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
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
|
/* GStreamer
* Copyright (C) 2004 Wim Taymans <wim@fluendo.com>
*
* gstbus.h: Header for GstBus subsystem
*
* 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., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#ifndef __GST_BUS_H__
#define __GST_BUS_H__
typedef struct _GstBus GstBus;
typedef struct _GstBusPrivate GstBusPrivate;
typedef struct _GstBusClass GstBusClass;
#include <gst/gstmessage.h>
#include <gst/gstclock.h>
G_BEGIN_DECLS
/* --- standard type macros --- */
#define GST_TYPE_BUS (gst_bus_get_type ())
#define GST_BUS(bus) (G_TYPE_CHECK_INSTANCE_CAST ((bus), GST_TYPE_BUS, GstBus))
#define GST_IS_BUS(bus) (G_TYPE_CHECK_INSTANCE_TYPE ((bus), GST_TYPE_BUS))
#define GST_BUS_CLASS(bclass) (G_TYPE_CHECK_CLASS_CAST ((bclass), GST_TYPE_BUS, GstBusClass))
#define GST_IS_BUS_CLASS(bclass) (G_TYPE_CHECK_CLASS_TYPE ((bclass), GST_TYPE_BUS))
#define GST_BUS_GET_CLASS(bus) (G_TYPE_INSTANCE_GET_CLASS ((bus), GST_TYPE_BUS, GstBusClass))
#define GST_BUS_CAST(bus) ((GstBus*)(bus))
/**
* GstBusFlags:
* @GST_BUS_FLUSHING: The bus is currently dropping all messages
* @GST_BUS_FLAG_LAST: offset to define more flags
*
* The standard flags that a bus may have.
*/
typedef enum {
GST_BUS_FLUSHING = (GST_OBJECT_FLAG_LAST << 0),
/* padding */
GST_BUS_FLAG_LAST = (GST_OBJECT_FLAG_LAST << 1)
} GstBusFlags;
/**
* GstBusSyncReply:
* @GST_BUS_DROP: drop the message
* @GST_BUS_PASS: pass the message to the async queue
* @GST_BUS_ASYNC: pass message to async queue, continue if message is handled
*
* The result values for a GstBusSyncHandler.
*/
typedef enum
{
GST_BUS_DROP = 0,
GST_BUS_PASS = 1,
GST_BUS_ASYNC = 2
} GstBusSyncReply;
/**
* GstBusSyncHandler:
* @bus: the #GstBus that sent the message
* @message: the #GstMessage
* @data: user data that has been given, when registering the handler
*
* Handler will be invoked synchronously, when a new message has been injected
* into the bus. This function is mostly used internally. Only one sync handler
* can be attached to a given bus.
*
* If the handler returns GST_BUS_DROP, it should unref the message, else the
* message should not be unreffed by the sync handler.
*
* Returns: #GstBusSyncReply stating what to do with the message
*/
typedef GstBusSyncReply (*GstBusSyncHandler) (GstBus * bus, GstMessage * message, gpointer data);
/**
* GstBusFunc:
* @bus: the #GstBus that sent the message
* @message: the #GstMessage
* @data: user data that has been given, when registering the handler
*
* Specifies the type of function passed to gst_bus_add_watch() or
* gst_bus_add_watch_full(), which is called from the mainloop when a message
* is available on the bus.
*
* The message passed to the function will be unreffed after execution of this
* function so it should not be freed in the function.
*
* Note that this function is used as a GSourceFunc which means that returning
* FALSE will remove the GSource from the mainloop.
*
* Returns: %FALSE if the event source should be removed.
*/
typedef gboolean (*GstBusFunc) (GstBus * bus, GstMessage * message, gpointer data);
/**
* GstBus:
*
* The opaque #GstBus data structure.
*/
struct _GstBus
{
GstObject object;
/*< private >*/
GQueue *queue;
GMutex *queue_lock;
GstBusSyncHandler sync_handler;
gpointer sync_handler_data;
guint signal_watch_id;
guint num_signal_watchers;
/*< private >*/
GstBusPrivate *priv;
gpointer _gst_reserved[GST_PADDING - 1];
};
struct _GstBusClass
{
GstObjectClass parent_class;
/* signals */
void (*message) (GstBus *bus, GstMessage *message);
void (*sync_message) (GstBus *bus, GstMessage *message);
/*< private >*/
gpointer _gst_reserved[GST_PADDING];
};
GType gst_bus_get_type (void);
GstBus* gst_bus_new (void);
gboolean gst_bus_post (GstBus * bus, GstMessage * message);
gboolean gst_bus_have_pending (GstBus * bus);
GstMessage * gst_bus_peek (GstBus * bus);
GstMessage * gst_bus_pop (GstBus * bus);
GstMessage * gst_bus_pop_filtered (GstBus * bus, GstMessageType types);
GstMessage * gst_bus_timed_pop (GstBus * bus, GstClockTime timeout);
GstMessage * gst_bus_timed_pop_filtered (GstBus * bus, GstClockTime timeout, GstMessageType types);
void gst_bus_set_flushing (GstBus * bus, gboolean flushing);
/* synchronous dispatching */
void gst_bus_set_sync_handler (GstBus * bus, GstBusSyncHandler func,
gpointer data);
/* GSource based dispatching */
GSource * gst_bus_create_watch (GstBus * bus);
guint gst_bus_add_watch_full (GstBus * bus,
gint priority,
GstBusFunc func,
gpointer user_data,
GDestroyNotify notify);
guint gst_bus_add_watch (GstBus * bus,
GstBusFunc func,
gpointer user_data);
/* polling the bus */
GstMessage* gst_bus_poll (GstBus *bus, GstMessageType events,
GstClockTimeDiff timeout);
/* signal based dispatching helper functions. */
gboolean gst_bus_async_signal_func (GstBus *bus, GstMessage *message,
gpointer data);
GstBusSyncReply gst_bus_sync_signal_handler (GstBus *bus, GstMessage *message,
gpointer data);
/* convenience api to add/remove a gsource that emits the async signals */
void gst_bus_add_signal_watch (GstBus * bus);
void gst_bus_add_signal_watch_full (GstBus * bus, gint priority);
void gst_bus_remove_signal_watch (GstBus * bus);
void gst_bus_enable_sync_message_emission (GstBus * bus);
void gst_bus_disable_sync_message_emission (GstBus * bus);
G_END_DECLS
#endif /* __GST_BUS_H__ */
|