contrib/package/freifunk-watchdog:

[project/luci.git] / contrib / package / freifunk-watchdog / src / watchdog.c

diff --git a/contrib/package/freifunk-watchdog/src/watchdog.c b/contrib/package/freifunk-watchdog/src/watchdog.c
index d4ccff8..5caf6d5 100644 (file)
--- a/contrib/package/freifunk-watchdog/src/watchdog.c
+++ b/contrib/package/freifunk-watchdog/src/watchdog.c
@@ -131,13 +131,31 @@ static int find_process(const char *name)
        return -1;
 }
 
+/* Get the 5 minute load average */
+static double find_loadavg(void)
+{
+       int fd;
+       char buffer[10];
+       double load = 0.00;
+
+       if( (fd = open("/proc/loadavg", O_RDONLY)) > -1 )
+       {
+               if( read(fd, buffer, sizeof(buffer)) == sizeof(buffer) )
+                       load = atof(&buffer[5]);
+
+               close(fd);
+       }
+
+       return load;
+}
+
 /* Check if given uci file was updated */
 static int check_uci_update(const char *config, time_t *mtime)
 {
        struct stat s;
        char path[128];
 
-       snprintf(path, sizeof(path), "/etc/config/%s", config);
+       snprintf(path, sizeof(path), "/var/state/%s", config);
        if( stat(path, &s) > -1 )
        {
                if( (*mtime == 0) || (s.st_mtime > *mtime) )
@@ -145,20 +163,8 @@ static int check_uci_update(const char *config, time_t *mtime)
                        *mtime = s.st_mtime;
                        return 1;
                }
-               else
-               {
-                       snprintf(path, sizeof(path), "/var/state/%s", config);
-                       if( stat(path, &s) > -1 )
-                       {
-                               if( (*mtime == 0) || (s.st_mtime > *mtime) )
-                               {
-                                       *mtime = s.st_mtime;
-                                       return 1;
-                               }
-                       }
 
-                       return 0;
-               }
+               return 0;
        }
 
        return -1;
@@ -197,7 +203,7 @@ static void load_wifi_uci_add_iface(const char *section, struct uci_itr_ctx *itr
                                val++;
                        }
                }
-       
+
                if( val == 3 )
                {
                        syslog(LOG_INFO, "Monitoring %s: bssid=%s channel=%d",
@@ -252,6 +258,8 @@ static wifi_tuple_t * load_wifi_uci(wifi_tuple_t *ifs, time_t *modtime)
 static int do_daemon(void)
 {
        int iwfd;
+       int wdfd;
+       int wdtrigger = 1;
        int channel;
        char bssid[18];
 
@@ -260,32 +268,44 @@ static int do_daemon(void)
 
        int restart_wifi = 0;
        int restart_cron = 0;
+       int restart_sshd = 0;
+       int loadavg_panic = 0;
 
        openlog(SYSLOG_IDENT, 0, LOG_DAEMON);
        //daemon(1, 1);
 
        if( (iwfd = socket(AF_INET, SOCK_DGRAM, 0)) == -1 )
        {
-               perror("Can not open wireless control socket");
+               syslog(LOG_ERR, "Can not open wireless control socket: %s",
+                       strerror(errno));
+
                return 1;
        }
 
+       if( (wdfd = open(WATCH_DEVICE, O_WRONLY)) > -1 )
+       {
+               syslog(LOG_INFO, "Opened %s - polling each %i seconds",
+                       WATCH_DEVICE, INTERVAL);
+       }
+
        while( 1 )
        {
-               if( (ifs = load_wifi_uci(ifs, &modtime)) == NULL )
-               {
-                       printf("Can not load wireless uci. File corrupt?\n");
-                       return 1;
-               }
+               /* Check average load */
+               if( find_loadavg() >= LOAD_TRESHOLD )
+                       loadavg_panic++;
+               else
+                       loadavg_panic = 0;
 
                /* Check crond */
                if( find_process("crond") < 0 )
-               {
-                       syslog(LOG_WARNING, "The crond process died, restarting");
-                       restart_cron++;         
-               }
+                       restart_cron++;
+
+               /* Check SSHd */
+               if( find_process("dropbear") < 0 )
+                       restart_sshd++;
 
                /* Check wireless interfaces */
+               ifs = load_wifi_uci(ifs, &modtime);
                for( curif = ifs; curif; curif = curif->next )
                {
                        /* Get current channel and bssid */
@@ -312,7 +332,7 @@ static int do_daemon(void)
                        }
                        else
                        {
-                               syslog(LOG_WARNING, "Requested interface %s not present", curif->ifname);                               
+                               syslog(LOG_WARNING, "Requested interface %s not present", curif->ifname);
                        }
                }
 
@@ -321,7 +341,7 @@ static int do_daemon(void)
                if( restart_wifi >= HYSTERESIS )
                {
                        restart_wifi = 0;
-                       syslog(LOG_WARNING, "Restarting wireless");
+                       syslog(LOG_WARNING, "Channel or BSSID mismatch on wireless interface, restarting");
                        EXEC(WIFI_ACTION);
                }
 
@@ -329,13 +349,44 @@ static int do_daemon(void)
                if( restart_cron >= HYSTERESIS )
                {
                        restart_cron = 0;
-                       syslog(LOG_WARNING, "Restarting crond process");
-                       EXEC(CRON_ACTION);      
+                       syslog(LOG_WARNING, "The cron process died, restarting");
+                       EXEC(CRON_ACTION);
+               }
+
+               /* SSHd restart required? */
+               if( restart_sshd >= HYSTERESIS )
+               {
+                       restart_sshd = 0;
+                       syslog(LOG_WARNING, "The ssh process died, restarting");
+                       EXEC(SSHD_ACTION);
+               }
+
+               /* Is there a load problem? */
+               if( loadavg_panic >= HYSTERESIS )
+               {
+                       syslog(LOG_EMERG, "Critical system load level, triggering reset!");
+
+                       /* Try watchdog, fall back to reboot */
+                       if( wdfd > -1 )
+                               ioctl(wdfd, WDIOC_SETTIMEOUT, &wdtrigger);
+                       else
+                               EXEC(LOAD_ACTION);
                }
 
+               /* Reset watchdog timer */
+               if( wdfd > -1 )
+                       write(wdfd, '\0', 1);
+
                sleep(INTERVAL);
        }
 
+       if( wdfd > -1 )
+       {
+               syslog(LOG_INFO, "Stopping watchdog timer");
+               write(wdfd, WATCH_SHUTDOWN, 1);
+               close(wdfd);
+       }
+
        closelog();
        return 0;
 }