1236769Sobrien/* 2236769Sobrien * Copyright (c) 1987 Regents of the University of California. 3236769Sobrien * All rights reserved. 4236769Sobrien * 5236769Sobrien * Redistribution and use in source and binary forms, with or without 6236769Sobrien * modification, are permitted provided that the following conditions 7236769Sobrien * are met: 8236769Sobrien * 1. Redistributions of source code must retain the above copyright 9236769Sobrien * notice, this list of conditions and the following disclaimer. 10236769Sobrien * 2. Redistributions in binary form must reproduce the above copyright 11236769Sobrien * notice, this list of conditions and the following disclaimer in the 12236769Sobrien * documentation and/or other materials provided with the distribution. 13236769Sobrien * 3. All advertising materials mentioning features or use of this software 14236769Sobrien * must display the following acknowledgement: 15236769Sobrien * This product includes software developed by the University of 16236769Sobrien * California, Berkeley and its contributors. 17236769Sobrien * 4. Neither the name of the University nor the names of its contributors 18236769Sobrien * may be used to endorse or promote products derived from this software 19236769Sobrien * without specific prior written permission. 20236769Sobrien * 21236769Sobrien * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 22236769Sobrien * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 23236769Sobrien * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 24236769Sobrien * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 25236769Sobrien * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 26236769Sobrien * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 27236769Sobrien * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 28236769Sobrien * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 29236769Sobrien * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 30236769Sobrien * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 31236769Sobrien * SUCH DAMAGE. 32236769Sobrien */ 33236769Sobrien 34236769Sobrien#ifdef HAVE_CONFIG_H 35236769Sobrien# include "config.h" 36236769Sobrien#endif 37236769Sobrien#ifndef HAVE_SETENV 38236769Sobrien 39236769Sobrien#if defined(LIBC_SCCS) && !defined(lint) 40236769Sobrien/*static char *sccsid = "from: @(#)setenv.c 5.6 (Berkeley) 6/4/91";*/ 41236769Sobrienstatic char *rcsid = "$Id: setenv.c,v 1.5 1996/09/04 22:10:42 sjg Exp $"; 42236769Sobrien#endif /* LIBC_SCCS and not lint */ 43236769Sobrien 44236769Sobrien#include <stddef.h> 45236769Sobrien#include <stdlib.h> 46236769Sobrien#include <string.h> 47236769Sobrien 48236769Sobrien/* 49236769Sobrien * __findenv -- 50236769Sobrien * Returns pointer to value associated with name, if any, else NULL. 51236769Sobrien * Sets offset to be the offset of the name/value combination in the 52236769Sobrien * environmental array, for use by setenv(3) and unsetenv(3). 53236769Sobrien * Explicitly removes '=' in argument name. 54236769Sobrien * 55236769Sobrien * This routine *should* be a static; don't use it. 56236769Sobrien */ 57236769Sobrienstatic char * 58236769Sobrien__findenv(name, offset) 59236769Sobrien register char *name; 60236769Sobrien int *offset; 61236769Sobrien{ 62236769Sobrien extern char **environ; 63236769Sobrien register int len; 64236769Sobrien register char **P, *C; 65236769Sobrien 66236769Sobrien for (C = name, len = 0; *C && *C != '='; ++C, ++len); 67236769Sobrien for (P = environ; *P; ++P) 68236769Sobrien if (!strncmp(*P, name, len)) 69236769Sobrien if (*(C = *P + len) == '=') { 70236769Sobrien *offset = P - environ; 71236769Sobrien return(++C); 72236769Sobrien } 73236769Sobrien return(NULL); 74236769Sobrien} 75236769Sobrien 76236769Sobrien/* 77236769Sobrien * setenv -- 78236769Sobrien * Set the value of the environmental variable "name" to be 79236769Sobrien * "value". If rewrite is set, replace any current value. 80236769Sobrien */ 81236769Sobriensetenv(name, value, rewrite) 82236769Sobrien register const char *name; 83236769Sobrien register const char *value; 84236769Sobrien int rewrite; 85236769Sobrien{ 86236769Sobrien extern char **environ; 87236769Sobrien static int alloced; /* if allocated space before */ 88236769Sobrien register char *C; 89236769Sobrien int l_value, offset; 90236769Sobrien char *__findenv(); 91236769Sobrien 92236769Sobrien if (*value == '=') /* no `=' in value */ 93236769Sobrien ++value; 94236769Sobrien l_value = strlen(value); 95236769Sobrien if ((C = __findenv(name, &offset))) { /* find if already exists */ 96236769Sobrien if (!rewrite) 97236769Sobrien return (0); 98236769Sobrien if (strlen(C) >= l_value) { /* old larger; copy over */ 99236769Sobrien while (*C++ = *value++); 100236769Sobrien return (0); 101236769Sobrien } 102236769Sobrien } else { /* create new slot */ 103236769Sobrien register int cnt; 104236769Sobrien register char **P; 105236769Sobrien 106236769Sobrien for (P = environ, cnt = 0; *P; ++P, ++cnt); 107236769Sobrien if (alloced) { /* just increase size */ 108236769Sobrien environ = (char **)realloc((char *)environ, 109236769Sobrien (size_t)(sizeof(char *) * (cnt + 2))); 110236769Sobrien if (!environ) 111236769Sobrien return (-1); 112236769Sobrien } 113236769Sobrien else { /* get new space */ 114236769Sobrien alloced = 1; /* copy old entries into it */ 115236769Sobrien P = (char **)malloc((size_t)(sizeof(char *) * 116236769Sobrien (cnt + 2))); 117236769Sobrien if (!P) 118236769Sobrien return (-1); 119236769Sobrien bcopy(environ, P, cnt * sizeof(char *)); 120236769Sobrien environ = P; 121236769Sobrien } 122236769Sobrien environ[cnt + 1] = NULL; 123236769Sobrien offset = cnt; 124236769Sobrien } 125236769Sobrien for (C = (char *)name; *C && *C != '='; ++C); /* no `=' in name */ 126236769Sobrien if (!(environ[offset] = /* name + `=' + value */ 127236769Sobrien malloc((size_t)((int)(C - name) + l_value + 2)))) 128236769Sobrien return (-1); 129236769Sobrien for (C = environ[offset]; (*C = *name++) && *C != '='; ++C) 130236769Sobrien ; 131236769Sobrien for (*C++ = '='; *C++ = *value++; ) 132236769Sobrien ; 133236769Sobrien return (0); 134236769Sobrien} 135236769Sobrien 136236769Sobrien/* 137236769Sobrien * unsetenv(name) -- 138236769Sobrien * Delete environmental variable "name". 139236769Sobrien */ 140236769Sobrienvoid 141236769Sobrienunsetenv(name) 142236769Sobrien const char *name; 143236769Sobrien{ 144236769Sobrien extern char **environ; 145236769Sobrien register char **P; 146236769Sobrien int offset; 147236769Sobrien char *__findenv(); 148236769Sobrien 149236769Sobrien while (__findenv(name, &offset)) /* if set multiple times */ 150236769Sobrien for (P = &environ[offset];; ++P) 151236769Sobrien if (!(*P = *(P + 1))) 152236769Sobrien break; 153236769Sobrien} 154236769Sobrien#endif 155