1 /* 2 * Copyright (c) 1987, 1993 3 * The Regents of the University of California. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by the University of 16 * California, Berkeley and its contributors. 17 * 4. Neither the name of the University 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 REGENTS 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 REGENTS 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 /* based on @(#)setenv.c 8.1 (Berkeley) 6/4/93 */ 35 /* based on @(#)getenv.c 8.1 (Berkeley) 6/4/93 */ 36 37 #ifndef __STDC__ 38 #define const 39 #endif 40 41 #include <stddef.h> 42 #include <stdlib.h> 43 #include <string.h> 44 45 #ifndef __P 46 #define __P(x) () 47 #endif 48 static char *__findenv __P((const char *, int *)); 49 50 /* 51 * setenv -- 52 * Set the value of the environmental variable "name" to be 53 * "value". If rewrite is set, replace any current value. 54 */ 55 int 56 krb5_setenv(name, value, rewrite) 57 register const char *name; 58 register const char *value; 59 int rewrite; 60 { 61 #if HAVE_SETENV 62 return (setenv(name, value, rewrite)); 63 #else 64 extern char **environ; 65 static int alloced; /* if allocated space before */ 66 register char *c; 67 int l_value, offset; 68 69 if (*value == '=') /* no `=' in value */ 70 ++value; 71 l_value = strlen(value); 72 if ((c = __findenv(name, &offset))) { /* find if already exists */ 73 if (!rewrite) 74 return (0); 75 if (strlen(c) >= l_value) { /* old larger; copy over */ 76 while ((*c++ = *value++)); 77 return (0); 78 } 79 } else { /* create new slot */ 80 register int cnt; 81 register char **p; 82 83 for (p = environ, cnt = 0; *p; ++p, ++cnt); 84 if (alloced) { /* just increase size */ 85 environ = (char **)realloc((char *)environ, 86 (size_t)(sizeof(char *) * (cnt + 2))); 87 if (!environ) 88 return (-1); 89 } 90 else { /* get new space */ 91 alloced = 1; /* copy old entries into it */ 92 p = (char **)malloc((size_t)(sizeof(char *) * (cnt + 2))); 93 if (!p) 94 return (-1); 95 memcpy(p, environ, cnt * sizeof(char *)); 96 environ = p; 97 } 98 environ[cnt + 1] = NULL; 99 offset = cnt; 100 } 101 for (c = (char *)name; *c && *c != '='; ++c); /* no `=' in name */ 102 if (!(environ[offset] = /* name + `=' + value */ 103 malloc((size_t)((int)(c - name) + l_value + 2)))) 104 return (-1); 105 /* LINTED */ 106 for (c = environ[offset]; (*c = *name++) && (*c != '='); ++c); 107 for (*c++ = '='; (*c++ = *value++);); 108 return (0); 109 #endif 110 } 111 112 /* 113 * unsetenv(name) -- 114 * Delete environmental variable "name". 115 */ 116 void 117 krb5_unsetenv(name) 118 const char *name; 119 { 120 #if HAVE_UNSETENV 121 unsetenv(name); 122 #else 123 extern char **environ; 124 register char **p; 125 int offset; 126 127 while (__findenv(name, &offset)) /* if set multiple times */ 128 for (p = &environ[offset];; ++p) 129 /* LINTED */ 130 if (!(*p = *(p + 1))) 131 break; 132 #endif 133 } 134 135 /* 136 * getenv -- 137 * Returns ptr to value associated with name, if any, else NULL. 138 */ 139 char * 140 krb5_getenv(name) 141 const char *name; 142 { 143 #if HAVE_GETENV 144 return (getenv(name)); 145 #else 146 int offset; 147 148 return (__findenv(name, &offset)); 149 #endif 150 } 151 152 #if (!HAVE_GETENV || !HAVE_SETENV || !HAVE_UNSETENV) 153 /* 154 * __findenv -- 155 * Returns pointer to value associated with name, if any, else NULL. 156 * Sets offset to be the offset of the name/value combination in the 157 * environmental array, for use by setenv(3) and unsetenv(3). 158 * Explicitly removes '=' in argument name. 159 */ 160 static char * 161 __findenv(name, offset) 162 register const char *name; 163 int *offset; 164 { 165 extern char **environ; 166 register int len; 167 register const char *np; 168 register char **p, *c; 169 170 if (name == NULL || environ == NULL) 171 return (NULL); 172 for (np = name; *np && *np != '='; ++np) 173 continue; 174 len = np - name; 175 for (p = environ; (c = *p) != NULL; ++p) 176 if (strncmp(c, name, len) == 0 && c[len] == '=') { 177 *offset = p - environ; 178 return (c + len + 1); 179 } 180 return (NULL); 181 } 182 #endif 183