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
|
/* select filedescriptor handling, taken from:
* userspace logging daemon for the iptables ULOG target
* of the linux 2.4 netfilter subsystem.
*
* (C) 2000-2009 by Harald Welte <laforge@gnumonks.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation
*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <fcntl.h>
#include <stdio.h>
#include <osmocore/select.h>
#include <osmocore/linuxlist.h>
#include <osmocore/timer.h>
#include "../config.h"
#ifdef HAVE_SYS_SELECT_H
static int maxfd = 0;
static LLIST_HEAD(bsc_fds);
static int unregistered_count;
int bsc_register_fd(struct bsc_fd *fd)
{
int flags;
/* make FD nonblocking */
flags = fcntl(fd->fd, F_GETFL);
if (flags < 0)
return flags;
flags |= O_NONBLOCK;
flags = fcntl(fd->fd, F_SETFL, flags);
if (flags < 0)
return flags;
/* Register FD */
if (fd->fd > maxfd)
maxfd = fd->fd;
#ifdef BSC_FD_CHECK
struct bsc_fd *entry;
llist_for_each_entry(entry, &bsc_fds, list) {
if (entry == fd) {
fprintf(stderr, "Adding a bsc_fd that is already in the list.\n");
return 0;
}
}
#endif
llist_add_tail(&fd->list, &bsc_fds);
return 0;
}
void bsc_unregister_fd(struct bsc_fd *fd)
{
unregistered_count++;
llist_del(&fd->list);
}
int bsc_select_main(int polling)
{
struct bsc_fd *ufd, *tmp;
fd_set readset, writeset, exceptset;
int work = 0, rc;
struct timeval no_time = {0, 0};
FD_ZERO(&readset);
FD_ZERO(&writeset);
FD_ZERO(&exceptset);
/* prepare read and write fdsets */
llist_for_each_entry(ufd, &bsc_fds, list) {
if (ufd->when & BSC_FD_READ)
FD_SET(ufd->fd, &readset);
if (ufd->when & BSC_FD_WRITE)
FD_SET(ufd->fd, &writeset);
if (ufd->when & BSC_FD_EXCEPT)
FD_SET(ufd->fd, &exceptset);
}
bsc_timer_check();
if (!polling)
bsc_prepare_timers();
rc = select(maxfd+1, &readset, &writeset, &exceptset, polling ? &no_time : bsc_nearest_timer());
if (rc < 0)
return 0;
/* fire timers */
bsc_update_timers();
/* call registered callback functions */
restart:
unregistered_count = 0;
llist_for_each_entry_safe(ufd, tmp, &bsc_fds, list) {
int flags = 0;
if (FD_ISSET(ufd->fd, &readset)) {
flags |= BSC_FD_READ;
FD_CLR(ufd->fd, &readset);
}
if (FD_ISSET(ufd->fd, &writeset)) {
flags |= BSC_FD_WRITE;
FD_CLR(ufd->fd, &writeset);
}
if (FD_ISSET(ufd->fd, &exceptset)) {
flags |= BSC_FD_EXCEPT;
FD_CLR(ufd->fd, &exceptset);
}
if (flags) {
work = 1;
ufd->cb(ufd, flags);
}
/* ugly, ugly hack. If more than one filedescriptors were
* unregistered, they might have been consecutive and
* llist_for_each_entry_safe() is no longer safe */
/* this seems to happen with the last element of the list as well */
if (unregistered_count >= 1)
goto restart;
}
return work;
}
#endif /* _HAVE_SYS_SELECT_H */
|
