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
|
/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*-
*
* Copyright (C) 2007 Jonathan Matthew
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2, or (at your option)
* any later version.
*
* The Rhythmbox authors hereby grant permission for non-GPL compatible
* GStreamer plugins to be used and distributed together with GStreamer
* and Rhythmbox. This permission is above and beyond the permissions granted
* by the GPL license by which Rhythmbox is covered. If you modify this code
* you may extend this exception to your version of the code, but you are not
* obligated to do so. If you do not wish to do so, delete this exception
* statement from your version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
*/
#include "config.h"
#include <rb-async-queue-watch.h>
/**
* SECTION:rb-async-queue-watch
* @short_description: GSource for watching a GAsyncQueue in the main loop
*
* This provides a way to feed work items to the main loop using a #GAsyncQueue
* without polling it.
*/
/**
* RBAsyncQueueWatchFunc:
* @item: the item found in the queue
* @data: user data specified when creating the watch
*
* Callback to call when an item is found in the queue.
*/
typedef struct {
GSource source;
GAsyncQueue *queue;
} RBAsyncQueueWatch;
static gboolean
rb_async_queue_watch_prepare (GSource *source, gint *timeout)
{
RBAsyncQueueWatch *watch = (RBAsyncQueueWatch *)source;
*timeout = -1;
return (g_async_queue_length (watch->queue) > 0);
}
static gboolean
rb_async_queue_watch_check (GSource *source)
{
RBAsyncQueueWatch *watch = (RBAsyncQueueWatch *)source;
return (g_async_queue_length (watch->queue) > 0);
}
static gboolean
rb_async_queue_watch_dispatch (GSource *source, GSourceFunc callback, gpointer user_data)
{
RBAsyncQueueWatch *watch = (RBAsyncQueueWatch *)source;
RBAsyncQueueWatchFunc cb = (RBAsyncQueueWatchFunc)callback;
gpointer item;
item = g_async_queue_try_pop (watch->queue);
if (item == NULL) {
return TRUE;
}
if (cb == NULL) {
return FALSE;
}
cb (item, user_data);
return TRUE;
}
static void
rb_async_queue_watch_finalize (GSource *source)
{
RBAsyncQueueWatch *watch = (RBAsyncQueueWatch *)source;
if (watch->queue != NULL) {
g_async_queue_unref (watch->queue);
watch->queue = NULL;
}
}
static GSourceFuncs rb_async_queue_watch_funcs = {
rb_async_queue_watch_prepare,
rb_async_queue_watch_check,
rb_async_queue_watch_dispatch,
rb_async_queue_watch_finalize
};
/**
* rb_async_queue_watch_new:
* @queue: the #GAsyncQueue to watch
* @priority: priority value for the #GSource
* @callback: callback to invoke when the queue is non-empty
* @user_data: user data to pass to the callback
* @notify: function to call to clean up the user data for the callback
* @context: the #GMainContext to attach the source to
*
* Creates a new #GSource that triggers when the #GAsyncQueue is
* non-empty. This is used in rhythmbox to process queues within
* #RhythmDB in the main thread without polling.
*
* Return value: the ID of the new #GSource
*/
guint rb_async_queue_watch_new (GAsyncQueue *queue,
gint priority,
RBAsyncQueueWatchFunc callback,
gpointer user_data,
GDestroyNotify notify,
GMainContext *context)
{
GSource *source;
RBAsyncQueueWatch *watch;
guint id;
source = (GSource *) g_source_new (&rb_async_queue_watch_funcs,
sizeof (RBAsyncQueueWatch));
watch = (RBAsyncQueueWatch *)source;
watch->queue = g_async_queue_ref (queue);
if (priority != G_PRIORITY_DEFAULT)
g_source_set_priority (source, priority);
g_source_set_callback (source, (GSourceFunc) callback, user_data, notify);
id = g_source_attach (source, context);
g_source_unref (source);
return id;
}
|
