145 lines
3.4 KiB
C
145 lines
3.4 KiB
C
/* 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 as published by
|
|
* the Free Software Foundation; either version 2 of the License, or
|
|
* (at your option) any later 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
|
|
*/
|
|
|
|
#include <fcntl.h>
|
|
#include <stdio.h>
|
|
|
|
#include <osmocom/core/select.h>
|
|
#include <osmocom/core/linuxlist.h>
|
|
#include <osmocom/core/timer.h>
|
|
|
|
#include "../config.h"
|
|
|
|
#ifdef HAVE_SYS_SELECT_H
|
|
|
|
static int maxfd = 0;
|
|
static LLIST_HEAD(osmo_fds);
|
|
static int unregistered_count;
|
|
|
|
int osmo_fd_register(struct osmo_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 osmo_fd *entry;
|
|
llist_for_each_entry(entry, &osmo_fds, list) {
|
|
if (entry == fd) {
|
|
fprintf(stderr, "Adding a osmo_fd that is already in the list.\n");
|
|
return 0;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
llist_add_tail(&fd->list, &osmo_fds);
|
|
|
|
return 0;
|
|
}
|
|
|
|
void osmo_fd_unregister(struct osmo_fd *fd)
|
|
{
|
|
unregistered_count++;
|
|
llist_del(&fd->list);
|
|
}
|
|
|
|
int osmo_select_main(int polling)
|
|
{
|
|
struct osmo_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, &osmo_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);
|
|
}
|
|
|
|
osmo_timers_check();
|
|
|
|
if (!polling)
|
|
osmo_timers_prepare();
|
|
rc = select(maxfd+1, &readset, &writeset, &exceptset, polling ? &no_time : osmo_timers_nearest());
|
|
if (rc < 0)
|
|
return 0;
|
|
|
|
/* fire timers */
|
|
osmo_timers_update();
|
|
|
|
/* call registered callback functions */
|
|
restart:
|
|
unregistered_count = 0;
|
|
llist_for_each_entry_safe(ufd, tmp, &osmo_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 */
|