crypto/external/bsd/heimdal/dist/lib/roken/putenv.c

   1 /*      $NetBSD: putenv.c,v 1.1.1.1 2011/04/13 18:15:42 elric Exp $     */
   2
   3 /*
   4  * Copyright (c) 1995, 1996, 1997 Kungliga Tekniska Högskolan
   5  * (Royal Institute of Technology, Stockholm, Sweden).
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  *
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  *
  15  * 2. Redistributions in binary form must reproduce the above copyright
  16  *    notice, this list of conditions and the following disclaimer in the
  17  *    documentation and/or other materials provided with the distribution.
  18  *
  19  * 3. Neither the name of the Institute nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  */
  35
  36 #include <config.h>
  37
  38 #include <stdlib.h>
  39
  40 #if !HAVE_DECL_ENVIRON
  41 extern char **environ;
  42 #endif
  43
  44 /*
  45  * putenv --
  46  *      String points to a string of the form name=value.
  47  *
  48  *      Makes the value of the environment variable name equal to
  49  *      value by altering an existing variable or creating a new one.
  50  */
  51
  52 ROKEN_LIB_FUNCTION int ROKEN_LIB_CALL
  53 putenv(const char *string)
  54 {
  55     int i;
  56     const char *eq = (const char *)strchr(string, '=');
  57     int len;
  58
  59     if (eq == NULL)
  60         return 1;
  61     len = eq - string;
  62
  63     if(environ == NULL) {
  64         environ = malloc(sizeof(char*));
  65         if(environ == NULL)
  66             return 1;
  67         environ[0] = NULL;
  68     }
  69
  70     for(i = 0; environ[i] != NULL; i++)
  71         if(strncmp(string, environ[i], len) == 0) {
  72             environ[i] = string;
  73             return 0;
  74         }
  75     environ = realloc(environ, sizeof(char*) * (i + 2));
  76     if(environ == NULL)
  77         return 1;
  78     environ[i]   = string;
  79     environ[i+1] = NULL;
  80     return 0;
  81 }