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
  36 systemd_send_information (const char *info)
  37 {
  38 #if defined HAVE_SYSTEMD
  39   sd_notify (0, info);
  40 #else
  41   return;
  42 #endif
  43 }
  44
  45 /*
  46  * A return of 0 means that we are not watchdoged
  47  */
  48 static int
  49 systemd_get_watchdog_time (int the_process)
  50 {
  51 #if defined HAVE_SYSTEMD
  52   uint64_t usec;
  53   char *watchdog = NULL;
  54   int ret;
  55
  56   ret = sd_watchdog_enabled (0, &usec);
  57
  58   /*
  59    * If return is 0 -> we don't want watchdog
  60    * if return is < 0, some sort of failure occurred
  61    */
  62   if (ret < 0)
  63     return 0;
  64
  65   /*
  66    * systemd can return that this process
  67    * is not the expected sender of the watchdog timer
  68    * If we set the_process = 0 then we expect to
  69    * be able to send the watchdog to systemd
  70    * irrelevant of the pid of this process.
  71    */
  72   if (ret == 0 && the_process)
  73     return 0;
  74
  75   if (ret == 0 && !the_process)
  76     {
  77       watchdog = getenv ("WATCHDOG_USEC");
  78       if (!watchdog)
  79         return 0;
  80
  81       usec = atol (watchdog);
  82     }
  83
  84   return (usec / 1000000)/ 3;
  85 #else
  86   return 0;
  87 #endif
  88 }
  89
  90 void
  91 systemd_send_stopping (void)
  92 {
  93   systemd_send_information ("STOPPING=1");
  94 }
  95
  96 /*
  97  * How many seconds should we wait between watchdog sends
  98  */
  99 int wsecs = 0;
 100 struct thread_master *systemd_master = NULL;
 101
 102 static int
 103 systemd_send_watchdog (struct thread *t)
 104 {
 105   systemd_send_information ("WATCHDOG=1");
 106
 107   thread_add_timer(systemd_master, systemd_send_watchdog, NULL, wsecs, NULL);
 108
 109   return 1;
 110 }
 111
 112 void
 113 systemd_send_started (struct thread_master *m, int the_process)
 114 {
 115   assert (m != NULL);
 116
 117   wsecs = systemd_get_watchdog_time(the_process);
 118   systemd_master = m;
 119
 120   systemd_send_information ("READY=1");
 121   if (wsecs != 0)
 122     thread_add_timer(m, systemd_send_watchdog, m, wsecs, NULL);
 123 }