projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| f5016eda WJ |
1 | /* |
| 2 | * Copyright (c) 1987 Regents of the University of California. | |
| 3 | * 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 5.8 (Berkeley) 2/23/91"; | |
| 36 | #endif /* LIBC_SCCS and not lint */ | |
| 37 | ||
| 38 | #include <stdlib.h> | |
| 39 | #include <stddef.h> | |
| 40 | #include <string.h> | |
| 41 | ||
| 42 | /* | |
| 43 | * getenv -- | |
| 44 | * Returns ptr to value associated with name, if any, else NULL. | |
| 45 | */ | |
| 46 | char * | |
| 47 | getenv(name) | |
| 48 | const char *name; | |
| 49 | { | |
| 50 | int offset; | |
| 51 | char *_findenv(); | |
| 52 | ||
| 53 | return(_findenv(name, &offset)); | |
| 54 | } | |
| 55 | ||
| 56 | /* | |
| 57 | * _findenv -- | |
| 58 | * Returns pointer to value associated with name, if any, else NULL. | |
| 59 | * Sets offset to be the offset of the name/value combination in the | |
| 60 | * environmental array, for use by setenv(3) and unsetenv(3). | |
| 61 | * Explicitly removes '=' in argument name. | |
| 62 | * | |
| 63 | * This routine *should* be a static; don't use it. | |
| 64 | */ | |
| 65 | char * | |
| 66 | _findenv(name, offset) | |
| 67 | register char *name; | |
| 68 | int *offset; | |
| 69 | { | |
| 70 | extern char **environ; | |
| 71 | register int len; | |
| 72 | register char **P, *C; | |
| 73 | ||
| 74 | for (C = name, len = 0; *C && *C != '='; ++C, ++len); | |
| 75 | for (P = environ; *P; ++P) | |
| 76 | if (!strncmp(*P, name, len)) | |
| 77 | if (*(C = *P + len) == '=') { | |
| 78 | *offset = P - environ; | |
| 79 | return(++C); | |
| 80 | } | |
| 81 | return(NULL); | |
| 82 | } |