/* wydawca - automatic release submission daemon
   Copyright (C) 2007, 2009, 2010 Sergey Poznyakoff

   Wydawca is free software; you can redistribute it and/or modify it
   under the terms of the GNU General Public License as published by the
   Free Software Foundation; either version 3 of the License, or (at your
   option) any later version.

   Wydawca is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License along
   with wydawca. If not, see <http://www.gnu.org/licenses/>. */

#include "wydawca.h"

char *pidfile = LOCALSTATEDIR "/run/wydawca.pid";
int force_startup;


void
remove_pidfile (void)
{
  unlink (pidfile);
}

void
check_pidfile ()
{
  FILE *fp = fopen (pidfile, "r+");

  if (fp)
    {
      unsigned long pid = -1;
      if (fscanf (fp, "%lu\n", &pid) != 1)
	{
	  logmsg (LOG_ERR, _("malformed pidfile %s"), pidfile);
	  if (!force_startup)
	    exit (EX_UNAVAILABLE);
	}
      else 
	{
	  if (kill (pid, 0))
	    {
	      if (errno != ESRCH)
		{
		  logmsg (LOG_ERR,
			  _("cannot verify if PID %lu is running: %s"),
			  pid, strerror (errno));
		  if (!force_startup)
		    exit (EX_UNAVAILABLE);
		}
	    }
	  else if (!force_startup)
	    {
	      logmsg (LOG_ERR,
		      _("another wydawca instance may be running (PID %lu)"),
		      pid);
	      exit (EX_UNAVAILABLE);
	    }
	}
      logmsg (LOG_NOTICE, _("replacing pidfile %s (PID %lu)"),
	      pidfile, pid);
      fseek (fp, 0, SEEK_SET);
    }
  else if (errno != ENOENT)
    {
      logmsg (LOG_ERR, _("cannot open pidfile %s: %s"), pidfile,
	      strerror (errno));
      exit (EX_UNAVAILABLE);
    }
  else
    {
      fp = fopen (pidfile, "w");
      if (!fp)
	{
	  logmsg (LOG_ERR,
		  _("cannot open pidfile %s for writing: %s"),
		  pidfile, strerror (errno));
	  exit (EX_UNAVAILABLE);
	}
    }
  fprintf (fp, "%lu\n", (unsigned long) getpid ());
  fclose (fp);
}