lib/roken/write_pid.c

   1 /*
   2  * Copyright (c) 1999 - 2001 Kungliga Tekniska Högskolan
   3  * (Royal Institute of Technology, Stockholm, Sweden).
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  *
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  *
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  *
  17  * 3. Neither the name of the Institute nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #include <config.h>
  35
  36 #include "roken.h"
  37
  38 ROKEN_LIB_FUNCTION char * ROKEN_LIB_CALL
  39 pid_file_write (const char *progname)
  40 {
  41     char *ret = NULL;
  42     FILE *fp;
  43
  44     if (asprintf (&ret, "%s%s.pid", _PATH_VARRUN, progname) < 0 || ret == NULL)
  45         return NULL;
  46     fp = fopen (ret, "w");
  47     if (fp == NULL) {
  48         free (ret);
  49         return NULL;
  50     }
  51     fprintf (fp, "%u", (unsigned)getpid());
  52     fclose (fp);
  53     return ret;
  54 }
  55
  56 ROKEN_LIB_FUNCTION void ROKEN_LIB_CALL
  57 pid_file_delete (char **filename)
  58 {
  59     if (*filename != NULL) {
  60         unlink (*filename);
  61         free (*filename);
  62         *filename = NULL;
  63     }
  64 }
  65
  66 #ifndef HAVE_PIDFILE
  67 static char *pidfile_path;
  68
  69 static void
  70 pidfile_cleanup(void)
  71 {
  72     if(pidfile_path != NULL)
  73         pid_file_delete(&pidfile_path);
  74 }
  75
  76 ROKEN_LIB_FUNCTION void ROKEN_LIB_CALL
  77 pidfile(const char *basename)
  78 {
  79     if(pidfile_path != NULL)
  80         return;
  81     if(basename == NULL)
  82         basename = getprogname();
  83     pidfile_path = pid_file_write(basename);
  84 #if defined(HAVE_ATEXIT)
  85     atexit(pidfile_cleanup);
  86 #elif defined(HAVE_ON_EXIT)
  87     on_exit(pidfile_cleanup);
  88 #endif
  89 }
  90 #endif