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Annotation of prex-old/usr/lib/libc/stdlib/getenv.c, Revision 1.1.1.1

1.1       nbrk        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. Neither the name of the University nor the names of its contributors
                     14:  *    may be used to endorse or promote products derived from this software
                     15:  *    without specific prior written permission.
                     16:  *
                     17:  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
                     18:  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
                     19:  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
                     20:  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
                     21:  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
                     22:  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
                     23:  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
                     24:  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
                     25:  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
                     26:  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
                     27:  * SUCH DAMAGE.
                     28:  */
                     29:
                     30: #include <stdlib.h>
                     31: #include <stddef.h>
                     32: #include <string.h>
                     33:
                     34: extern char **environ;
                     35:
                     36: char *__findenv(const char *, int *);
                     37:
                     38: /*
                     39:  * getenv --
                     40:  *     Returns ptr to value associated with name, if any, else NULL.
                     41:  */
                     42: char *
                     43: getenv(name)
                     44:        const char *name;
                     45: {
                     46:        int offset;
                     47:
                     48:        return (__findenv(name, &offset));
                     49: }
                     50:
                     51: /*
                     52:  * __findenv --
                     53:  *     Returns pointer to value associated with name, if any, else NULL.
                     54:  *     Sets offset to be the offset of the name/value combination in the
                     55:  *     environmental array, for use by setenv(3) and unsetenv(3).
                     56:  *     Explicitly removes '=' in argument name.
                     57:  *
                     58:  *     This routine *should* be a static; don't use it.
                     59:  */
                     60: char *
                     61: __findenv(name, offset)
                     62:        const char *name;
                     63:        int *offset;
                     64: {
                     65:        size_t len;
                     66:        const char *np;
                     67:        char **p, *c;
                     68:
                     69:        if (name == NULL || environ == NULL)
                     70:                return (NULL);
                     71:        for (np = name; *np && *np != '='; ++np)
                     72:                continue;
                     73:        len = np - name;
                     74:        for (p = environ; (c = *p) != NULL; ++p)
                     75:                if (strncmp(c, name, len) == 0 && c[len] == '=') {
                     76:                        *offset = p - environ;
                     77:                        return (c + len + 1);
                     78:                }
                     79:        return (NULL);
                     80: }