2 * Copyright (C) 2004 Wim Taymans <wim@fluendo.com>
4 * gstbus.h: Header for GstBus 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.
25 typedef struct _GstBus GstBus;
26 typedef struct _GstBusClass GstBusClass;
28 #include <gst/gstmessage.h>
29 #include <gst/gstclock.h>
33 /* --- standard type macros --- */
34 #define GST_TYPE_BUS (gst_bus_get_type ())
35 #define GST_BUS(bus) (G_TYPE_CHECK_INSTANCE_CAST ((bus), GST_TYPE_BUS, GstBus))
36 #define GST_IS_BUS(bus) (G_TYPE_CHECK_INSTANCE_TYPE ((bus), GST_TYPE_BUS))
37 #define GST_BUS_CLASS(bclass) (G_TYPE_CHECK_CLASS_CAST ((bclass), GST_TYPE_BUS, GstBusClass))
38 #define GST_IS_BUS_CLASS(bclass) (G_TYPE_CHECK_CLASS_TYPE ((bclass), GST_TYPE_BUS))
39 #define GST_BUS_GET_CLASS(bus) (G_TYPE_INSTANCE_GET_CLASS ((bus), GST_TYPE_BUS, GstBusClass))
40 #define GST_BUS_CAST(bus) ((GstBus*)(bus))
44 * @GST_BUS_FLUSHING: The bus is currently dropping all messages
45 * @GST_BUS_FLAG_LAST: offset to define more flags
47 * The standard flags that a bus may have.
50 GST_BUS_FLUSHING = GST_OBJECT_FLAG_LAST,
52 GST_BUS_FLAG_LAST = GST_OBJECT_FLAG_LAST + 1
57 * @GST_BUS_DROP: drop the message
58 * @GST_BUS_PASS: pass the message to the async queue
59 * @GST_BUS_ASYNC: pass message to async queue, continue if message is handled
61 * The result values for a GstBusSyncHandler.
72 * @bus: the #GstBus that sent the message
73 * @message: the #GstMessage
74 * @data: user data that has been given, when registering the handler
76 * Handler will be invoked synchronously, when a new message has been injected
77 * into the bus. This function is mostly used internally. Only one sync handler
78 * can be attached to a given bus.
80 * Returns: #GstBusSyncReply stating what to do with the message
82 typedef GstBusSyncReply (*GstBusSyncHandler) (GstBus * bus, GstMessage * message, gpointer data);
86 * @bus: the #GstBus that sent the message
87 * @message: the #GstMessage
88 * @data: user data that has been given, when registering the handler
90 * Specifies the type of function passed to #gst_bus_add_watch() or
91 * #gst_bus_add_watch_full(), which is called from the mainloop when a message
92 * is available on the bus.
94 * The message passed to the function will be unreffed after execution of this
95 * function so it should not be freed in the function.
97 * Returns: %FALSE if the event source should be removed.
99 typedef gboolean (*GstBusFunc) (GstBus * bus, GstMessage * message, gpointer data);
109 GstBusSyncHandler sync_handler;
110 gpointer sync_handler_data;
112 guint signal_watch_id;
113 guint num_signal_watchers;
116 gpointer _gst_reserved[GST_PADDING];
121 GstObjectClass parent_class;
124 void (*message) (GstBus *bus, GstMessage *message);
125 void (*sync_message) (GstBus *bus, GstMessage *message);
128 gpointer _gst_reserved[GST_PADDING];
131 GType gst_bus_get_type (void);
133 GstBus* gst_bus_new (void);
135 gboolean gst_bus_post (GstBus * bus, GstMessage * message);
137 gboolean gst_bus_have_pending (GstBus * bus);
138 GstMessage * gst_bus_peek (GstBus * bus);
139 GstMessage * gst_bus_pop (GstBus * bus);
140 void gst_bus_set_flushing (GstBus * bus, gboolean flushing);
142 /* synchronous dispatching */
143 void gst_bus_set_sync_handler (GstBus * bus, GstBusSyncHandler func,
145 /* GSource based dispatching */
146 GSource * gst_bus_create_watch (GstBus * bus);
147 guint gst_bus_add_watch_full (GstBus * bus,
151 GDestroyNotify notify);
152 guint gst_bus_add_watch (GstBus * bus,
156 /* polling the bus */
157 GstMessage* gst_bus_poll (GstBus *bus, GstMessageType events,
158 GstClockTimeDiff timeout);
160 /* signal based dispatching helper functions. */
161 gboolean gst_bus_async_signal_func (GstBus *bus, GstMessage *message,
163 GstBusSyncReply gst_bus_sync_signal_handler (GstBus *bus, GstMessage *message,
166 /* convenience api to add/remove a gsource that emits the async signals */
167 void gst_bus_add_signal_watch (GstBus * bus);
168 void gst_bus_remove_signal_watch (GstBus * bus);
172 #endif /* __GST_BUS_H__ */