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 #if defined(LIBC_SCCS) && !defined(lint) 35 static char sccsid[] = "@(#)getenv.c 8.1 (Berkeley) 6/4/93"; 36 #endif /* LIBC_SCCS and not lint */ 37 #include <sys/cdefs.h> 38 __FBSDID("$FreeBSD$"); 39 40 #include <stdlib.h> 41 #include <stddef.h> 42 #include <string.h> 43 44 inline char *__findenv(const char *, int *); 45 46 /* 47 * __findenv -- 48 * Returns pointer to value associated with name, if any, else NULL. 49 * Sets offset to be the offset of the name/value combination in the 50 * environmental array, for use by setenv(3) and unsetenv(3). 51 * Explicitly removes '=' in argument name. 52 * 53 * This routine *should* be a static; don't use it. 54 */ 55 inline char * 56 __findenv(name, offset) 57 const char *name; 58 int *offset; 59 { 60 extern char **environ; 61 int len, i; 62 const char *np; 63 char **p, *cp; 64 65 if (name == NULL || environ == NULL) 66 return (NULL); 67 for (np = name; *np && *np != '='; ++np) 68 continue; 69 len = np - name; 70 for (p = environ; (cp = *p) != NULL; ++p) { 71 for (np = name, i = len; i && *cp; i--) 72 if (*cp++ != *np++) 73 break; 74 if (i == 0 && *cp++ == '=') { 75 *offset = p - environ; 76 return (cp); 77 } 78 } 79 return (NULL); 80 } 81 82 /* 83 * getenv -- 84 * Returns ptr to value associated with name, if any, else NULL. 85 */ 86 char * 87 getenv(name) 88 const char *name; 89 { 90 int offset; 91 92 return (__findenv(name, &offset)); 93 } 94