platform_system_core/init/watchdogd.cpp

72 lines
2.0 KiB
C++

/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <linux/watchdog.h>
#include "log.h"
#include "util.h"
#define DEV_NAME "/dev/watchdog"
int watchdogd_main(int argc, char **argv) {
InitKernelLogging(argv);
int interval = 10;
if (argc >= 2) interval = atoi(argv[1]);
int margin = 10;
if (argc >= 3) margin = atoi(argv[2]);
LOG(INFO) << "watchdogd started (interval " << interval << ", margin " << margin << ")!";
int fd = open(DEV_NAME, O_RDWR|O_CLOEXEC);
if (fd == -1) {
PLOG(ERROR) << "Failed to open " << DEV_NAME;
return 1;
}
int timeout = interval + margin;
int ret = ioctl(fd, WDIOC_SETTIMEOUT, &timeout);
if (ret) {
PLOG(ERROR) << "Failed to set timeout to " << timeout;
ret = ioctl(fd, WDIOC_GETTIMEOUT, &timeout);
if (ret) {
PLOG(ERROR) << "Failed to get timeout";
} else {
if (timeout > margin) {
interval = timeout - margin;
} else {
interval = 1;
}
LOG(WARNING) << "Adjusted interval to timeout returned by driver: "
<< "timeout " << timeout
<< ", interval " << interval
<< ", margin " << margin;
}
}
while (true) {
write(fd, "", 1);
sleep(interval);
}
}