lib/systemd.c

   1 /* lib/systemd Code
   2  * Copyright (C) 2016 Cumulus Networks, Inc.
   3  * Donald Sharp
   4  *
   5  * This file is part of Quagga.
   6  *
   7  * Quagga is free software; you can redistribute it and/or modify it
   8  * under the terms of the GNU General Public License as published by the
   9  * Free Software Foundation; either version 2, or (at your option) any
  10  * later version.
  11  *
  12  * Quagga is distributed in the hope that it will be useful, but
  13  * WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; see the file COPYING; if not, write to the Free Software
  19  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  20  */
  21
  22 #include <zebra.h>
  23
  24 #include "thread.h"
  25 #include "systemd.h"
  26
  27 #if defined HAVE_SYSTEMD
  28 #include <systemd/sd-daemon.h>
  29 #endif
  30
  31 /*
  32  * Wrapper this silliness if we
  33  * don't have systemd
  34  */
  35 void systemd_send_information(const char *info)
  36 {
  37 #if defined HAVE_SYSTEMD
  38         sd_notify(0, info);
  39 #else
  40         return;
  41 #endif
  42 }
  43
  44 /*
  45  * A return of 0 means that we are not watchdoged
  46  */
  47 static int systemd_get_watchdog_time(int the_process)
  48 {
  49 #if defined HAVE_SYSTEMD
  50         uint64_t usec;
  51         char *watchdog = NULL;
  52         int ret;
  53
  54         ret = sd_watchdog_enabled(0, &usec);
  55
  56         /*
  57          * If return is 0 -> we don't want watchdog
  58          * if return is < 0, some sort of failure occurred
  59          */
  60         if (ret < 0)
  61                 return 0;
  62
  63         /*
  64          * systemd can return that this process
  65          * is not the expected sender of the watchdog timer
  66          * If we set the_process = 0 then we expect to
  67          * be able to send the watchdog to systemd
  68          * irrelevant of the pid of this process.
  69          */
  70         if (ret == 0 && the_process)
  71                 return 0;
  72
  73         if (ret == 0 && !the_process) {
  74                 watchdog = getenv("WATCHDOG_USEC");
  75                 if (!watchdog)
  76                         return 0;
  77
  78                 usec = atol(watchdog);
  79         }
  80
  81         return (usec / 1000000) / 3;
  82 #else
  83         return 0;
  84 #endif
  85 }
  86
  87 void systemd_send_stopping(void)
  88 {
  89         systemd_send_information("STOPPING=1");
  90 }
  91
  92 /*
  93  * How many seconds should we wait between watchdog sends
  94  */
  95 int wsecs = 0;
  96 struct thread_master *systemd_master = NULL;
  97
  98 static int systemd_send_watchdog(struct thread *t)
  99 {
 100         systemd_send_information("WATCHDOG=1");
 101
 102         thread_add_timer(systemd_master, systemd_send_watchdog, NULL, wsecs,
 103                          NULL);
 104
 105         return 1;
 106 }
 107
 108 void systemd_send_started(struct thread_master *m, int the_process)
 109 {
 110         assert(m != NULL);
 111
 112         wsecs = systemd_get_watchdog_time(the_process);
 113         systemd_master = m;
 114
 115         systemd_send_information("READY=1");
 116         if (wsecs != 0)
 117                 thread_add_timer(m, systemd_send_watchdog, m, wsecs, NULL);
 118 }