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
193
194
195
|
/*
* Copyright (C) 2010 Tobias Brunner
* Hochschule fuer Technik Rapperswil
*
* 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 of the License, or (at your
* option) any later version. See <http://www.fsf.org/copyleft/gpl.txt>.
*
* 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.
*/
#include <unistd.h>
#include <fcntl.h>
#include "event_queue.h"
#include <debug.h>
#include <threading/mutex.h>
#include <utils/linked_list.h>
typedef struct private_event_queue_t private_event_queue_t;
/**
* Private data of event_queue_t class.
*/
struct private_event_queue_t {
/**
* Public event_queue_t interface.
*/
event_queue_t public;
/**
* List of queued events (event_t*).
*/
linked_list_t *events;
/**
* Mutex for event list.
*/
mutex_t *mutex;
/**
* Read end of the notification pipe.
*/
int read_fd;
/**
* Write end of the notification pipe.
*/
int write_fd;
};
typedef struct event_t event_t;
struct event_t {
/**
* Callback function.
*/
void (*callback)(void *data);
/**
* Data to supply to the callback.
*/
void *data;
/**
* Cleanup function.
*/
void (*cleanup)(void *data);
};
static event_t *event_create(void (*callback)(void *data), void *data,
void (*cleanup)(void *data))
{
event_t *this;
INIT(this,
.callback = callback,
.data = data,
.cleanup = cleanup,
);
return this;
}
static void event_destroy(event_t *this)
{
if (this->cleanup)
{
this->cleanup(this->data);
}
free(this);
}
METHOD(event_queue_t, get_event_fd, int,
private_event_queue_t *this)
{
return this->read_fd;
}
METHOD(event_queue_t, handle, void,
private_event_queue_t *this)
{
char buf[10];
linked_list_t *events;
event_t *event;
this->mutex->lock(this->mutex);
/* flush pipe */
while (read(this->read_fd, &buf, sizeof(buf)) == sizeof(buf));
/* replace the list, so we can unlock the mutex while executing the jobs */
events = this->events;
this->events = linked_list_create();
this->mutex->unlock(this->mutex);
while (events->remove_first(events, (void**)&event) == SUCCESS)
{
event->callback(event->data);
event_destroy(event);
}
events->destroy(events);
}
METHOD(event_queue_t, queue, void,
private_event_queue_t *this, void (*callback)(void *data), void *data,
void (*cleanup)(void *data))
{
event_t *event = event_create(callback, data, cleanup);
char c = 0;
this->mutex->lock(this->mutex);
this->events->insert_last(this->events, event);
ignore_result(write(this->write_fd, &c, 1));
this->mutex->unlock(this->mutex);
}
METHOD(event_queue_t, destroy, void,
private_event_queue_t *this)
{
this->mutex->lock(this->mutex);
this->events->destroy_function(this->events, (void*)event_destroy);
this->mutex->unlock(this->mutex);
this->mutex->destroy(this->mutex);
close(this->read_fd);
close(this->write_fd);
free(this);
}
bool set_nonblock(int socket)
{
int flags = fcntl(socket, F_GETFL);
return flags != -1 && fcntl(socket, F_SETFL, flags | O_NONBLOCK) != -1;
}
bool set_cloexec(int socket)
{
int flags = fcntl(socket, F_GETFD);
return flags != -1 && fcntl(socket, F_SETFD, flags | FD_CLOEXEC) != -1;
}
/*
* Described in header.
*/
event_queue_t *event_queue_create()
{
private_event_queue_t *this;
int fd[2];
INIT(this,
.public = {
.get_event_fd = _get_event_fd,
.handle = _handle,
.queue = _queue,
.destroy = _destroy,
},
.events = linked_list_create(),
.mutex = mutex_create(MUTEX_TYPE_DEFAULT),
);
if (pipe(fd) == -1 ||
!set_nonblock(fd[0]) || !set_cloexec(fd[0]) ||
!set_nonblock(fd[1]) || !set_cloexec(fd[1]))
{
DBG1(DBG_JOB, "failed to create pipe for job queue");
_destroy(this);
return NULL;
}
this->read_fd = fd[0];
this->write_fd = fd[1];
return &this->public;
}
|