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/wait.h>
  33 #include <sys/stat.h>
  34 #include <sys/ioctl.h>
  35 #include <sys/socket.h>
  36 #include <linux/types.h>
  37 #include <linux/watchdog.h>
  38
  39 #include "ucix.h"
  40 #include "wireless.22.h"
  41
  42
  43 /* Watchdog poll interval */
  44 #define BASE_INTERVAL   5
  45
  46 /* Action interval (N * BASE_INTERVAL) */
  47 #define ACTION_INTERVAL 6
  48
  49 /* Hysteresis */
  50 #define HYSTERESIS              3
  51
  52 /* How to call myself in the logs */
  53 #define SYSLOG_IDENT    "Freifunk Watchdog"
  54
  55 /* Wifi error action */
  56 #define WIFI_ACTION             "/sbin/wifi", "/sbin/wifi"
  57
  58 /* Crond error action */
  59 #define CRON_ACTION             "/etc/init.d/cron", "/etc/init.d/cron", "restart"
  60
  61 /* SSHd error action */
  62 #define SSHD_ACTION             "/etc/init.d/dropbear", "/etc/init.d/dropbear", "restart"
  63
  64 /* Watchdog device */
  65 #define WATCH_DEVICE    "/dev/watchdog"
  66 #define WATCH_SHUTDOWN  'V'
  67 #define WATCH_KEEPALIVE '\0'
  68
  69 /* System load error action and treshold */
  70 #define LOAD_TRESHOLD   15.00
  71 #define LOAD_ACTION             "/sbin/reboot", "/sbin/reboot"
  72
  73 /* Fallback binary name (passed by makefile) */
  74 #ifndef BINARY
  75 #define BINARY "ffwatchd"
  76 #endif
  77
  78
  79 /* ifname/bssid/channel tuples */
  80 struct wifi_tuple {
  81         char ifname[16];
  82         char bssid[18];
  83         int channel;
  84         struct wifi_tuple *next;
  85 };
  86
  87 /* structure to hold tuple-list and uci context during iteration */
  88 struct uci_itr_ctx {
  89         struct wifi_tuple *list;
  90         struct uci_context *ctx;
  91 };
  92
  93 typedef struct wifi_tuple wifi_tuple_t;
  94
  95
  96 /* ioctl() helper (stolen from iwlib) */
  97 static inline int
  98 iw_ioctl(int                  skfd,           /* Socket to the kernel */
  99          const char *         ifname,         /* Device name */
 100          int                  request,        /* WE ID */
 101          struct iwreq *       pwrq)           /* Fixed part of the request */
 102 {
 103   /* Set device name */
 104   strncpy(pwrq->ifr_ifrn.ifrn_name, ifname, 16);
 105
 106   /* Do the request */
 107   return(ioctl(skfd, request, pwrq));
 108 }
 109
 110 /* fork() & execl() helper */
 111 #define EXEC(x)                                                                                                         \
 112         do {                                                                                                                    \
 113                 switch(fork())                                                                                          \
 114                 {                                                                                                                       \
 115                         case -1:                                                                                                \
 116                                 syslog(LOG_CRIT, "Unable to fork child: %s",            \
 117                                         strerror(errno));                                                               \
 118                                 break;                                                                                          \
 119                                                                                                                                         \
 120                         case 0:                                                                                                 \
 121                                 execl(x, NULL);                                                                         \
 122                                 syslog(LOG_CRIT, "Unable to execute action: %s",        \
 123                                         strerror(errno));                                                               \
 124                                 return 1;                                                                                       \
 125                 }                                                                                                                       \
 126         } while(0)
 127