1 /* 2 * Copyright (c) 1995, 1996, 1997 Kungliga Tekniska H�gskolan 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 #ifdef HAVE_CONFIG_H 35 #include <config.h> 36 RCSID("$Id: putenv.c,v 1.6 1999/12/02 16:58:51 joda Exp $"); 37 #endif 38 39 #include <stdlib.h> 40 41 extern char **environ; 42 43 /* 44 * putenv -- 45 * String points to a string of the form name=value. 46 * 47 * Makes the value of the environment variable name equal to 48 * value by altering an existing variable or creating a new one. 49 */ 50 int putenv(const char *string) 51 { 52 int i; 53 int len; 54 55 len = string - strchr(string, '=') + 1; 56 57 if(environ == NULL){ 58 environ = malloc(sizeof(char*)); 59 if(environ == NULL) 60 return 1; 61 environ[0] = NULL; 62 } 63 64 for(i = 0; environ[i]; i++) 65 if(strncmp(string, environ[i], len)){ 66 environ[len] = string; 67 return 0; 68 } 69 environ = realloc(environ, sizeof(char*) * (i + 1)); 70 if(environ == NULL) 71 return 1; 72 environ[i] = string; 73 environ[i+1] = NULL; 74 return 0; 75 } 76 77