telnetproxy/event.c

311 lines
7.6 KiB
C
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2006-11-25 14:31:52 +01:00
/***************************************************************************
* Copyright (C) 10/2006 by Olaf Rempel *
* razzor@kopf-tisch.de *
* *
* 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 <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <sys/time.h>
#include <sys/types.h>
#include "list.h"
#include "logging.h"
#include "event.h"
static LIST_HEAD(readfd_list);
static LIST_HEAD(writefd_list);
static LIST_HEAD(exceptfd_list);
static LIST_HEAD(timeout_list);
struct fd_entry {
struct list_head list;
int fd;
int type;
int (*callback)(int fd, void *privdata);
void *privdata;
};
struct timeout_entry {
struct list_head list;
struct timeval timeout;
struct timeval nextrun;
int (*callback)(void *privdata);
void *privdata;
};
int event_add_fd(int fd, int type, int (*callback)(int fd, void *privdata), void *privdata)
{
if (fd < 0 || fd > FD_SETSIZE)
return -1;
struct fd_entry *entry;
entry = malloc(sizeof(struct fd_entry));
if (entry == NULL) {
log_print(LOG_ERROR, "event_add_fd(): out of memory");
return -1;
}
entry->fd = fd;
entry->type = type;
entry->callback = callback;
entry->privdata = privdata;
switch (type) {
case FD_READ:
list_add_tail(&entry->list, &readfd_list);
break;
case FD_WRITE:
list_add_tail(&entry->list, &writefd_list);
break;
case FD_EXCEPT:
list_add_tail(&entry->list, &exceptfd_list);
break;
default:
log_print(LOG_ERROR, "add_fd(): unknown type");
free(entry);
return -1;
}
return 0;
}
int event_remove_fd(int fd)
{
struct fd_entry *entry, *tmp;
list_for_each_entry_safe(entry, tmp, &readfd_list, list) {
if (entry->fd == fd) {
list_del(&entry->list);
free(entry);
return 0;
}
}
list_for_each_entry_safe(entry, tmp, &writefd_list, list) {
if (entry->fd == fd) {
list_del(&entry->list);
free(entry);
return 0;
}
}
list_for_each_entry_safe(entry, tmp, &exceptfd_list, list) {
if (entry->fd == fd) {
list_del(&entry->list);
free(entry);
return 0;
}
}
return -1;
}
static void calc_nextrun(struct timeval *timeout, struct timeval *nextrun)
{
struct timeval now;
gettimeofday(&now, NULL);
nextrun->tv_usec = now.tv_usec + timeout->tv_usec;
nextrun->tv_sec = now.tv_sec + timeout->tv_sec;
if (nextrun->tv_usec >= 1000000) {
nextrun->tv_usec -= 1000000;
nextrun->tv_sec++;
}
}
static void calc_timeout(struct timeval *timeout, struct timeval *nextrun)
{
struct timeval now;
gettimeofday(&now, NULL);
timeout->tv_usec = nextrun->tv_usec - now.tv_usec;
timeout->tv_sec = nextrun->tv_sec - now.tv_sec;
if (timeout->tv_usec < 0) {
timeout->tv_usec += 1000000;
timeout->tv_sec--;
}
}
static void schedule_nextrun(struct timeout_entry *entry)
{
struct timeout_entry *search;
list_for_each_entry(search, &timeout_list, list) {
if (search->nextrun.tv_sec > entry->nextrun.tv_sec) {
list_add_tail(&entry->list, &search->list);
return;
} else if (search->nextrun.tv_sec == entry->nextrun.tv_sec &&
search->nextrun.tv_usec > entry->nextrun.tv_usec) {
list_add_tail(&entry->list, &search->list);
return;
}
}
list_add_tail(&entry->list, &timeout_list);
}
int event_add_timeout(struct timeval *timeout, int (*callback)(void *privdata), void *privdata)
{
struct timeout_entry *entry;
entry = malloc(sizeof(struct timeout_entry));
if (entry == NULL) {
log_print(LOG_ERROR, "event_add_timeout(): out of memory");
return -1;
}
memcpy(&entry->timeout, timeout, sizeof(entry->timeout));
entry->callback = callback;
entry->privdata = privdata;
calc_nextrun(&entry->timeout, &entry->nextrun);
schedule_nextrun(entry);
return 0;
}
void event_loop(void)
{
while (1) {
fd_set readfds, *readfds_p = NULL;
fd_set writefds, *writefds_p = NULL;
fd_set exceptfds, *exceptfds_p =NULL;
struct timeval timeout, *timeout_p = NULL;
if (!list_empty(&readfd_list)) {
struct fd_entry *entry;
FD_ZERO(&readfds);
list_for_each_entry(entry, &readfd_list, list)
FD_SET(entry->fd, &readfds);
readfds_p = &readfds;
}
if (!list_empty(&writefd_list)) {
struct fd_entry *entry;
FD_ZERO(&writefds);
list_for_each_entry(entry, &writefd_list, list)
FD_SET(entry->fd, &writefds);
writefds_p = &writefds;
}
if (!list_empty(&exceptfd_list)) {
struct fd_entry *entry;
FD_ZERO(&exceptfds);
list_for_each_entry(entry, &exceptfd_list, list)
FD_SET(entry->fd, &exceptfds);
exceptfds_p = &exceptfds;
}
if (!list_empty(&timeout_list)) {
struct timeout_entry *entry, *tmp;
list_for_each_entry_safe(entry, tmp, &timeout_list, list) {
calc_timeout(&timeout, &entry->nextrun);
if (timeout.tv_sec >= 0 && timeout.tv_usec > 0) {
timeout_p = &timeout;
break;
}
// delayed timeout, exec NOW!
list_del(&entry->list);
int ret = entry->callback(entry->privdata);
if (ret == 0) {
calc_nextrun(&entry->timeout, &entry->nextrun);
schedule_nextrun(entry);
} else {
free(entry);
}
}
}
int i = select(FD_SETSIZE, readfds_p, writefds_p, exceptfds_p, timeout_p);
if (i < 0) {
/* On error, -1 is returned, and errno is set
* appropriately; the sets and timeout become
* undefined, so do not rely on their contents
* after an error.
*/
continue;
} else if (i == 0 && !list_empty(&timeout_list)) {
struct timeout_entry *entry;
entry = list_entry(timeout_list.next, typeof(*entry), list);
list_del(&entry->list);
int ret = entry->callback(entry->privdata);
if (ret == 0) {
calc_nextrun(&entry->timeout, &entry->nextrun);
schedule_nextrun(entry);
} else {
free(entry);
}
}
if (readfds_p) {
struct fd_entry *entry, *tmp;
list_for_each_entry_safe(entry, tmp, &readfd_list, list) {
if (!FD_ISSET(entry->fd, &readfds))
continue;
if (entry->callback(entry->fd, entry->privdata) != 0) {
list_del(&entry->list);
free(entry);
}
}
}
if (writefds_p) {
struct fd_entry *entry, *tmp;
list_for_each_entry_safe(entry, tmp, &writefd_list, list) {
if (FD_ISSET(entry->fd, &writefds))
continue;
if (entry->callback(entry->fd, entry->privdata) != 0) {
list_del(&entry->list);
free(entry);
}
}
}
if (exceptfds_p) {
struct fd_entry *entry, *tmp;
list_for_each_entry_safe(entry, tmp, &exceptfd_list, list) {
if (FD_ISSET(entry->fd, &exceptfds))
continue;
if (entry->callback(entry->fd, entry->privdata) != 0) {
list_del(&entry->list);
free(entry);
}
}
}
}
}