1 /* 2 * Copyright (C) 2012 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include <errno.h> 18 #include <fcntl.h> 19 #include <stdlib.h> 20 #include <string.h> 21 #include <unistd.h> 22 23 #include <linux/watchdog.h> 24 25 #include "log.h" 26 #include "util.h" 27 28 #define DEV_NAME "/dev/watchdog" 29 30 int watchdogd_main(int argc, char **argv) { 31 open_devnull_stdio(); 32 klog_init(); 33 klog_set_level(KLOG_NOTICE_LEVEL); 34 35 int interval = 10; 36 if (argc >= 2) interval = atoi(argv[1]); 37 38 int margin = 10; 39 if (argc >= 3) margin = atoi(argv[2]); 40 41 NOTICE("started (interval %d, margin %d)!\n", interval, margin); 42 43 int fd = open(DEV_NAME, O_RDWR|O_CLOEXEC); 44 if (fd == -1) { 45 ERROR("Failed to open %s: %s\n", DEV_NAME, strerror(errno)); 46 return 1; 47 } 48 49 int timeout = interval + margin; 50 int ret = ioctl(fd, WDIOC_SETTIMEOUT, &timeout); 51 if (ret) { 52 ERROR("Failed to set timeout to %d: %s\n", timeout, strerror(errno)); 53 ret = ioctl(fd, WDIOC_GETTIMEOUT, &timeout); 54 if (ret) { 55 ERROR("Failed to get timeout: %s\n", strerror(errno)); 56 } else { 57 if (timeout > margin) { 58 interval = timeout - margin; 59 } else { 60 interval = 1; 61 } 62 WARNING("Adjusted interval to timeout returned by driver:" 63 " timeout %d, interval %d, margin %d\n", 64 timeout, interval, margin); 65 } 66 } 67 68 while (true) { 69 write(fd, "", 1); 70 sleep(interval); 71 } 72 } 73
