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 /* Watchdog poll interval */
  43 #define BASE_INTERVAL   5
  44
  45 /* Action interval (N * BASE_INTERVAL) */
  46 #define ACTION_INTERVAL 6
  47
  48 /* Hysteresis */
  49 #define HYSTERESIS              3
  50
  51 /* How to call myself in the logs */
  52 #define SYSLOG_IDENT    "Freifunk Watchdog"
  53
  54 /* Wifi error action */
  55 #define WIFI_ACTION             "/sbin/wifi", "/sbin/wifi"
  56
  57 /* Crond error action */
  58 #define CRON_ACTION             "/etc/init.d/cron", "/etc/init.d/cron", "restart"
  59
  60 /* SSHd error action */
  61 #define SSHD_ACTION             "/etc/init.d/dropbear", "/etc/init.d/dropbear", "restart"
  62
  63 /* Watchdog device */
  64 #define WATCH_DEVICE    "/dev/watchdog"
  65 #define WATCH_SHUTDOWN  'V'
  66 #define WATCH_KEEPALIVE '\0'
  67
  68 /* System load error action and treshold */
  69 #define LOAD_TRESHOLD   15.00
  70 #define LOAD_ACTION             "/sbin/reboot"
  71
  72 /* Fallback binary name (passed by makefile) */
  73 #ifndef BINARY
  74 #define BINARY "ffwatchd"
  75 #endif
  76
  77
  78 /* ifname/bssid/channel tuples */
  79 struct wifi_tuple {
  80         char ifname[16];
  81         char bssid[18];
  82         int channel;
  83         struct wifi_tuple *next;
  84 };
  85
  86 /* structure to hold tuple-list and uci context during iteration */
  87 struct uci_itr_ctx {
  88         struct wifi_tuple *list;
  89         struct uci_context *ctx;
  90 };
  91
  92 typedef struct wifi_tuple wifi_tuple_t;
  93
  94
  95 /* ioctl() helper (stolen from iwlib) */
  96 static inline int
  97 iw_ioctl(int                  skfd,           /* Socket to the kernel */
  98          const char *         ifname,         /* Device name */
  99          int                  request,        /* WE ID */
 100          struct iwreq *       pwrq)           /* Fixed part of the request */
 101 {
 102   /* Set device name */
 103   strncpy(pwrq->ifr_ifrn.ifrn_name, ifname, 16);
 104
 105   /* Do the request */
 106   return(ioctl(skfd, request, pwrq));
 107 }
 108
 109 /* fork() & execl() helper */
 110 #define EXEC(x)                                                                                                                 \
 111         do {                                                                                                                            \
 112                 switch(fork())                                                                                                  \
 113                 {                                                                                                                               \
 114                         case -1:                                                                                                        \
 115                                 syslog(LOG_CRIT, "Unable to fork child: %s",                    \
 116                                         strerror(errno));                                                                       \
 117                                                                                                                                                 \
 118                                         break;                                                                                          \
 119                                                                                                                                                 \
 120                                 case 0:                                                                                                 \
 121                                         execl(x, NULL);                                                                         \
 122                                         syslog(LOG_CRIT, "Unable to execute action: %s",        \
 123                                                 strerror(errno));                                                               \
 124                                                                                                                                                 \
 125                                         return 1;                                                                                       \
 126                 }                                                                                                                               \
 127         } while(0)
 128