/* * 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) { open_devnull_stdio(); klog_init(); klog_set_level(KLOG_NOTICE_LEVEL); int interval = 10; if (argc >= 2) interval = atoi(argv[1]); int margin = 10; if (argc >= 3) margin = atoi(argv[2]); NOTICE("watchdogd started (interval %d, margin %d)!\n", interval, margin); int fd = open(DEV_NAME, O_RDWR|O_CLOEXEC); if (fd == -1) { ERROR("watchdogd: Failed to open %s: %s\n", DEV_NAME, strerror(errno)); return 1; } int timeout = interval + margin; int ret = ioctl(fd, WDIOC_SETTIMEOUT, &timeout); if (ret) { ERROR("watchdogd: Failed to set timeout to %d: %s\n", timeout, strerror(errno)); ret = ioctl(fd, WDIOC_GETTIMEOUT, &timeout); if (ret) { ERROR("watchdogd: Failed to get timeout: %s\n", strerror(errno)); } else { if (timeout > margin) { interval = timeout - margin; } else { interval = 1; } ERROR("watchdogd: Adjusted interval to timeout returned by driver: timeout %d, interval %d, margin %d\n", timeout, interval, margin); } } while (true) { write(fd, "", 1); sleep(interval); } }