Eric Andersen | ffde867 | 2001-01-25 23:40:32 +0000 | [diff] [blame] | 1 | /* vi: set sw=4 ts=4: */ |
| 2 | /* |
| 3 | * Mini watchdog implementation for busybox |
| 4 | * |
Eric Andersen | cde8f53 | 2003-07-22 07:39:18 +0000 | [diff] [blame] | 5 | * Copyright (C) 2003 Paul Mundt <lethal@linux-sh.org> |
Bernhard Reutner-Fischer | 5f6d67b | 2006-06-03 20:53:18 +0000 | [diff] [blame] | 6 | * Copyright (C) 2006 Bernhard Fischer <busybox@busybox.net> |
Eric Andersen | ffde867 | 2001-01-25 23:40:32 +0000 | [diff] [blame] | 7 | * |
Rob Landley | 1b751c8 | 2005-10-28 09:24:33 +0000 | [diff] [blame] | 8 | * Licensed under the GPL v2 or later, see the file LICENSE in this tarball. |
Eric Andersen | ffde867 | 2001-01-25 23:40:32 +0000 | [diff] [blame] | 9 | */ |
| 10 | |
Denis Vlasenko | b6adbf1 | 2007-05-26 19:00:18 +0000 | [diff] [blame] | 11 | #include "libbb.h" |
Eric Andersen | ffde867 | 2001-01-25 23:40:32 +0000 | [diff] [blame] | 12 | |
Mike Frysinger | cd68a2e | 2006-06-26 21:31:17 +0000 | [diff] [blame] | 13 | #define OPT_FOREGROUND 0x01 |
| 14 | #define OPT_TIMER 0x02 |
| 15 | |
Denis Vlasenko | b44c790 | 2008-03-17 09:29:43 +0000 | [diff] [blame] | 16 | static void watchdog_shutdown(int sig ATTRIBUTE_UNUSED) |
Eric Andersen | cde8f53 | 2003-07-22 07:39:18 +0000 | [diff] [blame] | 17 | { |
Denis Vlasenko | 3638cc4 | 2007-09-05 12:13:51 +0000 | [diff] [blame] | 18 | static const char V = 'V'; |
| 19 | |
| 20 | write(3, &V, 1); /* Magic, see watchdog-api.txt in kernel */ |
Denis Vlasenko | cfa2b3a | 2007-03-14 21:55:41 +0000 | [diff] [blame] | 21 | if (ENABLE_FEATURE_CLEAN_UP) |
| 22 | close(3); |
Bernhard Reutner-Fischer | 636a1f8 | 2008-05-19 09:29:47 +0000 | [diff] [blame] | 23 | exit(EXIT_SUCCESS); |
Eric Andersen | cde8f53 | 2003-07-22 07:39:18 +0000 | [diff] [blame] | 24 | } |
| 25 | |
Denis Vlasenko | 9b49a5e | 2007-10-11 10:05:36 +0000 | [diff] [blame] | 26 | int watchdog_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
Rob Landley | 1b751c8 | 2005-10-28 09:24:33 +0000 | [diff] [blame] | 27 | int watchdog_main(int argc, char **argv) |
Eric Andersen | ffde867 | 2001-01-25 23:40:32 +0000 | [diff] [blame] | 28 | { |
Denis Vlasenko | 67b23e6 | 2006-10-03 21:00:06 +0000 | [diff] [blame] | 29 | unsigned opts; |
Denis Vlasenko | 3638cc4 | 2007-09-05 12:13:51 +0000 | [diff] [blame] | 30 | unsigned timer_duration = 30000; /* Userspace timer duration, in milliseconds */ |
Rob Landley | 1b751c8 | 2005-10-28 09:24:33 +0000 | [diff] [blame] | 31 | char *t_arg; |
Bernhard Reutner-Fischer | 5f6d67b | 2006-06-03 20:53:18 +0000 | [diff] [blame] | 32 | |
Denis Vlasenko | 5a14202 | 2007-03-26 13:20:54 +0000 | [diff] [blame] | 33 | opt_complementary = "=1"; /* must have 1 argument */ |
Denis Vlasenko | fe7cd64 | 2007-08-18 15:32:12 +0000 | [diff] [blame] | 34 | opts = getopt32(argv, "Ft:", &t_arg); |
Mike Frysinger | cd68a2e | 2006-06-26 21:31:17 +0000 | [diff] [blame] | 35 | |
Denis Vlasenko | 3638cc4 | 2007-09-05 12:13:51 +0000 | [diff] [blame] | 36 | if (opts & OPT_TIMER) { |
| 37 | static const struct suffix_mult suffixes[] = { |
| 38 | { "ms", 1 }, |
| 39 | { "", 1000 }, |
| 40 | { } |
| 41 | }; |
| 42 | timer_duration = xatou_sfx(t_arg, suffixes); |
| 43 | } |
Eric Andersen | cde8f53 | 2003-07-22 07:39:18 +0000 | [diff] [blame] | 44 | |
Denis Vlasenko | 9067f13 | 2007-03-24 12:11:17 +0000 | [diff] [blame] | 45 | if (!(opts & OPT_FOREGROUND)) { |
Denis Vlasenko | 5a14202 | 2007-03-26 13:20:54 +0000 | [diff] [blame] | 46 | bb_daemonize_or_rexec(DAEMON_CHDIR_ROOT, argv); |
Denis Vlasenko | 9067f13 | 2007-03-24 12:11:17 +0000 | [diff] [blame] | 47 | } |
Eric Andersen | cde8f53 | 2003-07-22 07:39:18 +0000 | [diff] [blame] | 48 | |
Denis Vlasenko | cf7cf62 | 2008-03-19 19:38:46 +0000 | [diff] [blame] | 49 | bb_signals(BB_FATAL_SIGS, watchdog_shutdown); |
Eric Andersen | cde8f53 | 2003-07-22 07:39:18 +0000 | [diff] [blame] | 50 | |
Denis Vlasenko | cfa2b3a | 2007-03-14 21:55:41 +0000 | [diff] [blame] | 51 | /* Use known fd # - avoid needing global 'int fd' */ |
Denis Vlasenko | 5a14202 | 2007-03-26 13:20:54 +0000 | [diff] [blame] | 52 | xmove_fd(xopen(argv[argc - 1], O_WRONLY), 3); |
Eric Andersen | ffde867 | 2001-01-25 23:40:32 +0000 | [diff] [blame] | 53 | |
Denis Vlasenko | b44c790 | 2008-03-17 09:29:43 +0000 | [diff] [blame] | 54 | // TODO? |
| 55 | // if (!(opts & OPT_TIMER)) { |
| 56 | // if (ioctl(fd, WDIOC_GETTIMEOUT, &timer_duration) == 0) |
| 57 | // timer_duration *= 500; |
| 58 | // else |
| 59 | // timer_duration = 30000; |
| 60 | // } |
| 61 | |
Eric Andersen | ffde867 | 2001-01-25 23:40:32 +0000 | [diff] [blame] | 62 | while (1) { |
Eric Andersen | c7bda1c | 2004-03-15 08:29:22 +0000 | [diff] [blame] | 63 | /* |
Eric Andersen | cde8f53 | 2003-07-22 07:39:18 +0000 | [diff] [blame] | 64 | * Make sure we clear the counter before sleeping, as the counter value |
| 65 | * is undefined at this point -- PFM |
| 66 | */ |
Denis Vlasenko | 3638cc4 | 2007-09-05 12:13:51 +0000 | [diff] [blame] | 67 | write(3, "", 1); /* write zero byte */ |
| 68 | usleep(timer_duration * 1000L); |
Eric Andersen | ffde867 | 2001-01-25 23:40:32 +0000 | [diff] [blame] | 69 | } |
Denis Vlasenko | 3638cc4 | 2007-09-05 12:13:51 +0000 | [diff] [blame] | 70 | return EXIT_SUCCESS; /* - not reached, but gcc 4.2.1 is too dumb! */ |
Eric Andersen | ffde867 | 2001-01-25 23:40:32 +0000 | [diff] [blame] | 71 | } |