contrib/package/freifunk-watchdog: workaround CONFIG_WATCHDOG_NOWAYOUT, trap signals
[project/luci.git] / contrib / package / freifunk-watchdog / src / watchdog.h
1 /*
2 * This program is free software; you can redistribute it and/or modify
3 * it under the terms of the GNU General Public License as published by
4 * the Free Software Foundation; either version 2 of the License, or
5 * (at your option) any later version.
6 *
7 * This program is distributed in the hope that it will be useful,
8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
10 * GNU General Public License for more details.
11 *
12 * You should have received a copy of the GNU General Public License
13 * along with this program; if not, write to the Free Software
14 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
15 *
16 * Copyright (C) 2009 Jo-Philipp Wich <xm@subsignal.org>
17 */
18
19 #include <stdio.h>
20 #include <string.h>
21 #include <unistd.h>
22 #include <stdint.h>
23 #include <stdlib.h>
24 #include <syslog.h>
25 #include <ctype.h>
26 #include <errno.h>
27 #include <dirent.h>
28 #include <fcntl.h>
29 #include <math.h>
30 #include <time.h>
31 #include <signal.h>
32 #include <sys/stat.h>
33 #include <sys/ioctl.h>
34 #include <sys/socket.h>
35 #include <linux/types.h>
36 #include <linux/watchdog.h>
37
38 #include "ucix.h"
39 #include "wireless.22.h"
40
41
42 /* Check interval */
43 #define INTERVAL 30
44
45 /* Hysteresis */
46 #define HYSTERESIS 3
47
48 /* How to call myself in the logs */
49 #define SYSLOG_IDENT "Freifunk Watchdog"
50
51 /* Wifi error action */
52 #define WIFI_ACTION "/sbin/wifi", "/sbin/wifi"
53
54 /* Crond error action */
55 #define CRON_ACTION "/etc/init.d/cron", "/etc/init.d/cron", "restart"
56
57 /* SSHd error action */
58 #define SSHD_ACTION "/etc/init.d/dropbear", "/etc/init.d/dropbear", "restart"
59
60 /* Watchdog device */
61 #define WATCH_DEVICE "/dev/watchdog"
62 #define WATCH_SHUTDOWN 'V'
63 #define WATCH_KEEPALIVE '\0'
64
65 /* System load error action and treshold */
66 #define LOAD_TRESHOLD 5.00
67 #define LOAD_ACTION "/sbin/reboot"
68
69 /* Fallback binary name (passed by makefile) */
70 #ifndef BINARY
71 #define BINARY "ffwatchd"
72 #endif
73
74
75 /* ifname/bssid/channel tuples */
76 struct wifi_tuple {
77 char ifname[16];
78 char bssid[18];
79 int channel;
80 struct wifi_tuple *next;
81 };
82
83 /* structure to hold tuple-list and uci context during iteration */
84 struct uci_itr_ctx {
85 struct wifi_tuple *list;
86 struct uci_context *ctx;
87 };
88
89 typedef struct wifi_tuple wifi_tuple_t;
90
91
92 /* ioctl() helper (stolen from iwlib) */
93 static inline int
94 iw_ioctl(int skfd, /* Socket to the kernel */
95 const char * ifname, /* Device name */
96 int request, /* WE ID */
97 struct iwreq * pwrq) /* Fixed part of the request */
98 {
99 /* Set device name */
100 strncpy(pwrq->ifr_ifrn.ifrn_name, ifname, 16);
101
102 /* Do the request */
103 return(ioctl(skfd, request, pwrq));
104 }
105
106 /* fork() & execl() helper */
107 #define EXEC(x) \
108 do { \
109 switch(fork()) \
110 { \
111 case -1: \
112 syslog(LOG_CRIT, "Unable to fork child: %s", \
113 strerror(errno)); \
114 \
115 break; \
116 \
117 case 0: \
118 execl(x, NULL); \
119 syslog(LOG_CRIT, "Unable to execute action: %s", \
120 strerror(errno)); \
121 \
122 return 1; \
123 } \
124 } while(0)
125