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 <linux/watchdog.h> 20#include <stdlib.h> 21#include <string.h> 22#include <unistd.h> 23 24#include <android-base/logging.h> 25 26#include "log.h" 27 28#ifdef _INIT_INIT_H 29#error "Do not include init.h in files used by ueventd or watchdogd; it will expose init's globals" 30#endif 31 32#define DEV_NAME "/dev/watchdog" 33 34namespace android { 35namespace init { 36 37int watchdogd_main(int argc, char **argv) { 38 InitKernelLogging(argv); 39 40 int interval = 10; 41 if (argc >= 2) interval = atoi(argv[1]); 42 43 int margin = 10; 44 if (argc >= 3) margin = atoi(argv[2]); 45 46 LOG(INFO) << "watchdogd started (interval " << interval << ", margin " << margin << ")!"; 47 48 int fd = open(DEV_NAME, O_RDWR|O_CLOEXEC); 49 if (fd == -1) { 50 PLOG(ERROR) << "Failed to open " << DEV_NAME; 51 return 1; 52 } 53 54 int timeout = interval + margin; 55 int ret = ioctl(fd, WDIOC_SETTIMEOUT, &timeout); 56 if (ret) { 57 PLOG(ERROR) << "Failed to set timeout to " << timeout; 58 ret = ioctl(fd, WDIOC_GETTIMEOUT, &timeout); 59 if (ret) { 60 PLOG(ERROR) << "Failed to get timeout"; 61 } else { 62 if (timeout > margin) { 63 interval = timeout - margin; 64 } else { 65 interval = 1; 66 } 67 LOG(WARNING) << "Adjusted interval to timeout returned by driver: " 68 << "timeout " << timeout 69 << ", interval " << interval 70 << ", margin " << margin; 71 } 72 } 73 74 while (true) { 75 write(fd, "", 1); 76 sleep(interval); 77 } 78} 79 80} // namespace init 81} // namespace android 82