Files
domo/src/3P/procd/watchdog.c

136 lines
2.6 KiB
C

/*
* Copyright (C) 2013 Felix Fietkau <nbd@openwrt.org>
* Copyright (C) 2013 John Crispin <blogic@openwrt.org>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License version 2.1
* 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.
*/
#include <linux/watchdog.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <libubox/uloop.h>
#include "procd.h"
#include "watchdog.h"
#define WDT_PATH "/dev/watchdog"
static struct uloop_timeout wdt_timeout;
static int wdt_fd = -1;
static int wdt_frequency = 5;
void watchdog_ping(void)
{
DEBUG(4, "Ping\n");
if (wdt_fd >= 0 && write(wdt_fd, "X", 1) < 0)
ERROR("WDT failed to write: %s\n", strerror(errno));
}
static void watchdog_timeout_cb(struct uloop_timeout *t)
{
watchdog_ping();
uloop_timeout_set(t, wdt_frequency * 1000);
}
void watchdog_set_stopped(bool val)
{
if (val)
uloop_timeout_cancel(&wdt_timeout);
else
watchdog_timeout_cb(&wdt_timeout);
}
bool watchdog_get_stopped(void)
{
return !wdt_timeout.pending;
}
int watchdog_timeout(int timeout)
{
if (wdt_fd < 0)
return 0;
if (timeout) {
DEBUG(4, "Set watchdog timeout: %ds\n", timeout);
ioctl(wdt_fd, WDIOC_SETTIMEOUT, &timeout);
}
ioctl(wdt_fd, WDIOC_GETTIMEOUT, &timeout);
return timeout;
}
int watchdog_frequency(int frequency)
{
if (wdt_fd < 0)
return 0;
if (frequency) {
DEBUG(4, "Set watchdog frequency: %ds\n", frequency);
wdt_frequency = frequency;
}
return wdt_frequency;
}
char* watchdog_fd(void)
{
static char fd_buf[3];
if (wdt_fd < 0)
return NULL;
snprintf(fd_buf, sizeof(fd_buf), "%d", wdt_fd);
return fd_buf;
}
void watchdog_init(int preinit)
{
char *env = getenv("WDTFD");
if (wdt_fd >= 0)
return;
wdt_timeout.cb = watchdog_timeout_cb;
if (env) {
DEBUG(2, "Watchdog handover: fd=%s\n", env);
wdt_fd = atoi(env);
unsetenv("WDTFD");
} else {
wdt_fd = open("/dev/watchdog", O_WRONLY);
}
if (wdt_fd < 0)
return;
if (!preinit)
fcntl(wdt_fd, F_SETFD, fcntl(wdt_fd, F_GETFD) | FD_CLOEXEC);
LOG("- watchdog -\n");
watchdog_timeout(30);
watchdog_timeout_cb(&wdt_timeout);
DEBUG(4, "Opened watchdog with timeout %ds\n", watchdog_timeout(0));
}
void watchdog_no_cloexec(void)
{
if (wdt_fd < 0)
return;
fcntl(wdt_fd, F_SETFD, fcntl(wdt_fd, F_GETFD) & ~FD_CLOEXEC);
}