1 /* select filedescriptor handling, taken from:
2 * userspace logging daemon for the iptables ULOG target
3 * of the linux 2.4 netfilter subsystem.
5 * (C) 2000-2009 by Harald Welte <laforge@gnumonks.org>
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2
9 * as published by the Free Software Foundation
11 * This program 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
14 * GNU General Public License for more details.
16 * You should have received a copy of the GNU General Public License
17 * along with this program; if not, write to the Free Software
18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 #include <osmocore/select.h>
23 #include <osmocore/linuxlist.h>
24 #include <osmocore/timer.h>
26 #include "../config.h"
28 #ifdef HAVE_SYS_SELECT_H
31 static LLIST_HEAD(bsc_fds);
32 static int unregistered_count;
34 int bsc_register_fd(struct bsc_fd *fd)
38 /* make FD nonblocking */
39 flags = fcntl(fd->fd, F_GETFL);
43 flags = fcntl(fd->fd, F_SETFL, flags);
51 llist_add_tail(&fd->list, &bsc_fds);
56 void bsc_unregister_fd(struct bsc_fd *fd)
62 int bsc_select_main(int polling)
64 struct bsc_fd *ufd, *tmp;
65 fd_set readset, writeset, exceptset;
67 struct timeval no_time = {0, 0};
73 /* prepare read and write fdsets */
74 llist_for_each_entry(ufd, &bsc_fds, list) {
75 if (ufd->when & BSC_FD_READ)
76 FD_SET(ufd->fd, &readset);
78 if (ufd->when & BSC_FD_WRITE)
79 FD_SET(ufd->fd, &writeset);
81 if (ufd->when & BSC_FD_EXCEPT)
82 FD_SET(ufd->fd, &exceptset);
89 rc = select(maxfd+1, &readset, &writeset, &exceptset, polling ? &no_time : bsc_nearest_timer());
96 /* call registered callback functions */
98 unregistered_count = 0;
99 llist_for_each_entry_safe(ufd, tmp, &bsc_fds, list) {
102 if (FD_ISSET(ufd->fd, &readset)) {
103 flags |= BSC_FD_READ;
104 FD_CLR(ufd->fd, &readset);
107 if (FD_ISSET(ufd->fd, &writeset)) {
108 flags |= BSC_FD_WRITE;
109 FD_CLR(ufd->fd, &writeset);
112 if (FD_ISSET(ufd->fd, &exceptset)) {
113 flags |= BSC_FD_EXCEPT;
114 FD_CLR(ufd->fd, &exceptset);
121 /* ugly, ugly hack. If more than one filedescriptors were
122 * unregistered, they might have been consecutive and
123 * llist_for_each_entry_safe() is no longer safe */
124 /* this seems to happen with the last element of the list as well */
125 if (unregistered_count >= 1)
131 #endif /* _HAVE_SYS_SELECT_H */