1*0Sstevel@tonic-gate /* 2*0Sstevel@tonic-gate * Copyright (c) 1997, by Sun Microsystems, Inc. 3*0Sstevel@tonic-gate * All rights reserved. 4*0Sstevel@tonic-gate */ 5*0Sstevel@tonic-gate 6*0Sstevel@tonic-gate #if defined(LIBC_SCCS) && !defined(lint) 7*0Sstevel@tonic-gate static char sccsid[] = "@(#)setenv.c 8.1 (Berkeley) 6/4/93"; 8*0Sstevel@tonic-gate static char rcsid[] = "$Id: setenv.c,v 8.4 1997/04/24 22:00:38 vixie Exp $"; 9*0Sstevel@tonic-gate #endif /* LIBC_SCCS and not lint */ 10*0Sstevel@tonic-gate 11*0Sstevel@tonic-gate /* 12*0Sstevel@tonic-gate * Copyright (c) 1987, 1993 13*0Sstevel@tonic-gate * The Regents of the University of California. All rights reserved. 14*0Sstevel@tonic-gate * 15*0Sstevel@tonic-gate * Redistribution and use in source and binary forms, with or without 16*0Sstevel@tonic-gate * modification, are permitted provided that the following conditions 17*0Sstevel@tonic-gate * are met: 18*0Sstevel@tonic-gate * 1. Redistributions of source code must retain the above copyright 19*0Sstevel@tonic-gate * notice, this list of conditions and the following disclaimer. 20*0Sstevel@tonic-gate * 2. Redistributions in binary form must reproduce the above copyright 21*0Sstevel@tonic-gate * notice, this list of conditions and the following disclaimer in the 22*0Sstevel@tonic-gate * documentation and/or other materials provided with the distribution. 23*0Sstevel@tonic-gate * 3. All advertising materials mentioning features or use of this software 24*0Sstevel@tonic-gate * must display the following acknowledgement: 25*0Sstevel@tonic-gate * This product includes software developed by the University of 26*0Sstevel@tonic-gate * California, Berkeley and its contributors. 27*0Sstevel@tonic-gate * 4. Neither the name of the University nor the names of its contributors 28*0Sstevel@tonic-gate * may be used to endorse or promote products derived from this software 29*0Sstevel@tonic-gate * without specific prior written permission. 30*0Sstevel@tonic-gate * 31*0Sstevel@tonic-gate * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 32*0Sstevel@tonic-gate * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 33*0Sstevel@tonic-gate * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 34*0Sstevel@tonic-gate * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 35*0Sstevel@tonic-gate * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 36*0Sstevel@tonic-gate * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 37*0Sstevel@tonic-gate * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 38*0Sstevel@tonic-gate * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 39*0Sstevel@tonic-gate * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 40*0Sstevel@tonic-gate * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 41*0Sstevel@tonic-gate * SUCH DAMAGE. 42*0Sstevel@tonic-gate */ 43*0Sstevel@tonic-gate 44*0Sstevel@tonic-gate 45*0Sstevel@tonic-gate #pragma ident "%Z%%M% %I% %E% SMI" 46*0Sstevel@tonic-gate 47*0Sstevel@tonic-gate #include "port_before.h" 48*0Sstevel@tonic-gate 49*0Sstevel@tonic-gate #include <stddef.h> 50*0Sstevel@tonic-gate #include <stdlib.h> 51*0Sstevel@tonic-gate #include <string.h> 52*0Sstevel@tonic-gate 53*0Sstevel@tonic-gate #include "port_after.h" 54*0Sstevel@tonic-gate 55*0Sstevel@tonic-gate #if !defined(NEED_SETENV) 56*0Sstevel@tonic-gate int __bindcompat_setenv; 57*0Sstevel@tonic-gate #else 58*0Sstevel@tonic-gate 59*0Sstevel@tonic-gate extern char **environ; 60*0Sstevel@tonic-gate 61*0Sstevel@tonic-gate static char *findenv(const char *name, int *offset); 62*0Sstevel@tonic-gate 63*0Sstevel@tonic-gate /* 64*0Sstevel@tonic-gate * setenv -- 65*0Sstevel@tonic-gate * Set the value of the environmental variable "name" to be 66*0Sstevel@tonic-gate * "value". If rewrite is set, replace any current value. 67*0Sstevel@tonic-gate */ 68*0Sstevel@tonic-gate setenv(const char *name, const char *value, int rewrite) { 69*0Sstevel@tonic-gate extern char **environ; 70*0Sstevel@tonic-gate static int alloced; /* if allocated space before */ 71*0Sstevel@tonic-gate char *c; 72*0Sstevel@tonic-gate int l_value, offset; 73*0Sstevel@tonic-gate 74*0Sstevel@tonic-gate if (*value == '=') /* no `=' in value */ 75*0Sstevel@tonic-gate ++value; 76*0Sstevel@tonic-gate l_value = strlen(value); 77*0Sstevel@tonic-gate if ((c = findenv(name, &offset))) { /* find if already exists */ 78*0Sstevel@tonic-gate if (!rewrite) 79*0Sstevel@tonic-gate return (0); 80*0Sstevel@tonic-gate if (strlen(c) >= l_value) { /* old larger; copy over */ 81*0Sstevel@tonic-gate while (*c++ = *value++); 82*0Sstevel@tonic-gate return (0); 83*0Sstevel@tonic-gate } 84*0Sstevel@tonic-gate } else { /* create new slot */ 85*0Sstevel@tonic-gate int cnt; 86*0Sstevel@tonic-gate char **p; 87*0Sstevel@tonic-gate 88*0Sstevel@tonic-gate for (p = environ, cnt = 0; *p; ++p, ++cnt); 89*0Sstevel@tonic-gate if (alloced) { /* just increase size */ 90*0Sstevel@tonic-gate environ = (char **)realloc((char *)environ, 91*0Sstevel@tonic-gate (size_t)(sizeof(char *) * (cnt + 2))); 92*0Sstevel@tonic-gate if (!environ) 93*0Sstevel@tonic-gate return (-1); 94*0Sstevel@tonic-gate } 95*0Sstevel@tonic-gate else { /* get new space */ 96*0Sstevel@tonic-gate alloced = 1; /* copy old entries into it */ 97*0Sstevel@tonic-gate p = malloc((size_t)(sizeof(char *) * (cnt + 2))); 98*0Sstevel@tonic-gate if (!p) 99*0Sstevel@tonic-gate return (-1); 100*0Sstevel@tonic-gate memcpy(p, environ, cnt * sizeof(char *)); 101*0Sstevel@tonic-gate environ = p; 102*0Sstevel@tonic-gate } 103*0Sstevel@tonic-gate environ[cnt + 1] = NULL; 104*0Sstevel@tonic-gate offset = cnt; 105*0Sstevel@tonic-gate } 106*0Sstevel@tonic-gate for (c = (char *)name; *c && *c != '='; ++c); /* no `=' in name */ 107*0Sstevel@tonic-gate if (!(environ[offset] = /* name + `=' + value */ 108*0Sstevel@tonic-gate malloc((size_t)((int)(c - name) + l_value + 2)))) 109*0Sstevel@tonic-gate return (-1); 110*0Sstevel@tonic-gate for (c = environ[offset]; (*c = *name++) && *c != '='; ++c); 111*0Sstevel@tonic-gate for (*c++ = '='; *c++ = *value++;); 112*0Sstevel@tonic-gate return (0); 113*0Sstevel@tonic-gate } 114*0Sstevel@tonic-gate 115*0Sstevel@tonic-gate /* 116*0Sstevel@tonic-gate * unsetenv(name) -- 117*0Sstevel@tonic-gate * Delete environmental variable "name". 118*0Sstevel@tonic-gate */ 119*0Sstevel@tonic-gate void 120*0Sstevel@tonic-gate unsetenv(const char *name) { 121*0Sstevel@tonic-gate char **p; 122*0Sstevel@tonic-gate int offset; 123*0Sstevel@tonic-gate 124*0Sstevel@tonic-gate while (findenv(name, &offset)) /* if set multiple times */ 125*0Sstevel@tonic-gate for (p = &environ[offset];; ++p) 126*0Sstevel@tonic-gate if (!(*p = *(p + 1))) 127*0Sstevel@tonic-gate break; 128*0Sstevel@tonic-gate } 129*0Sstevel@tonic-gate 130*0Sstevel@tonic-gate /* 131*0Sstevel@tonic-gate * findenv -- 132*0Sstevel@tonic-gate * Returns pointer to value associated with name, if any, else NULL. 133*0Sstevel@tonic-gate * Sets offset to be the offset of the name/value combination in the 134*0Sstevel@tonic-gate * environmental array, for use by setenv(3) and unsetenv(3). 135*0Sstevel@tonic-gate * Explicitly removes '=' in argument name. 136*0Sstevel@tonic-gate * 137*0Sstevel@tonic-gate * This routine *should* be a static; don't use it. 138*0Sstevel@tonic-gate */ 139*0Sstevel@tonic-gate static char * 140*0Sstevel@tonic-gate findenv(const char *name, int *offset) { 141*0Sstevel@tonic-gate const char *np; 142*0Sstevel@tonic-gate char **p, *c; 143*0Sstevel@tonic-gate int len; 144*0Sstevel@tonic-gate 145*0Sstevel@tonic-gate if (name == NULL || environ == NULL) 146*0Sstevel@tonic-gate return (NULL); 147*0Sstevel@tonic-gate for (np = name; *np && *np != '='; ++np) 148*0Sstevel@tonic-gate continue; 149*0Sstevel@tonic-gate len = np - name; 150*0Sstevel@tonic-gate for (p = environ; (c = *p) != NULL; ++p) 151*0Sstevel@tonic-gate if (strncmp(c, name, len) == 0 && c[len] == '=') { 152*0Sstevel@tonic-gate *offset = p - environ; 153*0Sstevel@tonic-gate return (c + len + 1); 154*0Sstevel@tonic-gate } 155*0Sstevel@tonic-gate return (NULL); 156*0Sstevel@tonic-gate } 157*0Sstevel@tonic-gate #endif 158