src/simple/getenv.c

   1 /*
   2  * Copyright (c) 2013 Apple Computer, Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 #include <TargetConditionals.h>
  25
  26 #include <stdlib.h>
  27
  28 #include <_simple.h>
  29
  30 #include <platform/string.h>
  31 #include <platform/compat.h>
  32
  33 const char *
  34 _simple_getenv(const char *envp[], const char *var) {
  35     const char **p;
  36     size_t var_len;
  37
  38     var_len = strlen(var);
  39
  40     for (p = envp; p && *p; p++) {
  41         size_t p_len = strlen(*p);
  42
  43         if (p_len >= var_len &&
  44             memcmp(*p, var, var_len) == 0 &&
  45             (*p)[var_len] == '=') {
  46             return &(*p)[var_len + 1];
  47         }
  48     }
  49
  50     return NULL;
  51 }