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
22 #include <linux/watchdog.h>
23
24 #include "log.h"
25 #include "util.h"
26
27 #define DEV_NAME "/dev/watchdog"
28
watchdogd_main(int argc,char ** argv)29 int watchdogd_main(int argc, char **argv)
30 {
31 int fd;
32 int ret;
33 int interval = 10;
34 int margin = 10;
35 int timeout;
36
37 open_devnull_stdio();
38 klog_init();
39
40 INFO("Starting watchdogd\n");
41
42 if (argc >= 2)
43 interval = atoi(argv[1]);
44
45 if (argc >= 3)
46 margin = atoi(argv[2]);
47
48 timeout = interval + margin;
49
50 fd = open(DEV_NAME, O_RDWR);
51 if (fd < 0) {
52 ERROR("watchdogd: Failed to open %s: %s\n", DEV_NAME, strerror(errno));
53 return 1;
54 }
55
56 ret = ioctl(fd, WDIOC_SETTIMEOUT, &timeout);
57 if (ret) {
58 ERROR("watchdogd: Failed to set timeout to %d: %s\n", timeout, strerror(errno));
59 ret = ioctl(fd, WDIOC_GETTIMEOUT, &timeout);
60 if (ret) {
61 ERROR("watchdogd: Failed to get timeout: %s\n", strerror(errno));
62 } else {
63 if (timeout > margin)
64 interval = timeout - margin;
65 else
66 interval = 1;
67 ERROR("watchdogd: Adjusted interval to timeout returned by driver: timeout %d, interval %d, margin %d\n",
68 timeout, interval, margin);
69 }
70 }
71
72 while(1) {
73 write(fd, "", 1);
74 sleep(interval);
75 }
76 }
77
78