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| Rev | Author | Line No. | Line |
|---|---|---|---|
| 6099 | serge | 1 | /* |
| 2 | FUNCTION |
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| 3 | <<_getenv_r>>---look up environment variable |
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| 4 | |||
| 5 | INDEX |
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| 6 | _getenv_r |
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| 7 | INDEX |
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| 8 | environ |
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| 9 | |||
| 10 | ANSI_SYNOPSIS |
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| 11 | #include |
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| 12 | char *_getenv_r(struct _reent *<[reent_ptr]>, const char *<[name]>); |
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| 13 | |||
| 14 | TRAD_SYNOPSIS |
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| 15 | #include |
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| 16 | char *_getenv_r(<[reent_ptr]>, <[name]>) |
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| 17 | struct _reent *<[reent_ptr]>; |
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| 18 | char *<[name]>; |
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| 19 | |||
| 20 | DESCRIPTION |
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| 21 | <<_getenv_r>> searches the list of environment variable names and values |
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| 22 | (using the global pointer ``< |
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| 23 | name matches the string at <[name]>. If a variable name matches, |
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| 24 | <<_getenv_r>> returns a pointer to the associated value. |
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| 25 | |||
| 26 | RETURNS |
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| 27 | A pointer to the (string) value of the environment variable, or |
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| 28 | < |
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| 29 | |||
| 30 | PORTABILITY |
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| 31 | <<_getenv_r>> is not ANSI; the rules for properly forming names of environment |
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| 32 | variables vary from one system to another. This implementation does not |
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| 33 | permit '=' to be in identifiers. |
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| 34 | |||
| 35 | <<_getenv_r>> requires a global pointer < |
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| 36 | */ |
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| 37 | |||
| 38 | /* This file may have been modified by DJ Delorie (Jan 1991). If so, |
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| 39 | ** these modifications are Copyright (C) 1991 DJ Delorie. |
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| 40 | */ |
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| 41 | |||
| 42 | /* |
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| 43 | * Copyright (c) 1987 Regents of the University of California. |
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| 44 | * All rights reserved. |
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| 45 | * |
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| 46 | * Redistribution and use in source and binary forms are permitted |
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| 47 | * provided that: (1) source distributions retain this entire copyright |
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| 48 | * notice and comment, and (2) distributions including binaries display |
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| 49 | * the following acknowledgement: ``This product includes software |
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| 50 | * developed by the University of California, Berkeley and its contributors'' |
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| 51 | * in the documentation or other materials provided with the distribution |
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| 52 | * and in all advertising materials mentioning features or use of this |
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| 53 | * software. Neither the name of the University nor the names of its |
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| 54 | * contributors may be used to endorse or promote products derived |
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| 55 | * from this software without specific prior written permission. |
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| 56 | * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR |
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| 57 | * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED |
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| 58 | * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. |
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| 59 | */ |
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| 60 | |||
| 61 | #include |
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| 62 | #include |
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| 63 | #include |
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| 64 | #include "envlock.h" |
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| 65 | |||
| 66 | extern char **environ; |
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| 67 | |||
| 68 | /* Only deal with a pointer to environ, to work around subtle bugs with shared |
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| 69 | libraries and/or small data systems where the user declares his own |
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| 70 | 'environ'. */ |
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| 71 | static char ***p_environ = &environ; |
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| 72 | |||
| 73 | /* |
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| 74 | * _findenv -- |
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| 75 | * Returns pointer to value associated with name, if any, else NULL. |
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| 76 | * Sets offset to be the offset of the name/value combination in the |
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| 77 | * environmental array, for use by setenv(3) and unsetenv(3). |
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| 78 | * |
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| 79 | * This routine *should* be a static; don't use it. |
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| 80 | */ |
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| 81 | |||
| 82 | char * |
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| 83 | _DEFUN (_findenv_r, (reent_ptr, name, offset), |
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| 84 | struct _reent *reent_ptr _AND |
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| 85 | register _CONST char *name _AND |
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| 86 | int *offset) |
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| 87 | { |
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| 9959 | turbocat | 88 | register int len; |
| 89 | register char **p; |
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| 90 | _CONST char *c; |
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| 91 | |||
| 92 | ENV_LOCK; |
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| 93 | |||
| 94 | /* In some embedded systems, this does not get set. This protects |
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| 95 | newlib from dereferencing a bad pointer. */ |
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| 96 | if (!*p_environ) |
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| 97 | { |
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| 98 | ENV_UNLOCK; |
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| 99 | return NULL; |
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| 100 | } |
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| 101 | |||
| 102 | c = name; |
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| 103 | while (*c && *c != '=') c++; |
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| 104 | |||
| 105 | /* Identifiers may not contain an '=', so cannot match if does */ |
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| 106 | if(*c != '=') |
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| 107 | { |
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| 108 | len = c - name; |
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| 109 | for (p = *p_environ; *p; ++p) |
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| 110 | if (!strncmp (*p, name, len)) |
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| 111 | if (*(c = *p + len) == '=') |
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| 112 | { |
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| 113 | *offset = p - *p_environ; |
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| 114 | ENV_UNLOCK; |
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| 115 | return (char *) (++c); |
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| 116 | } |
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| 117 | } |
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| 118 | ENV_UNLOCK; |
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| 6099 | serge | 119 | return NULL; |
| 120 | } |
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| 121 | |||
| 122 | /* |
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| 123 | * _getenv_r -- |
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| 124 | * Returns ptr to value associated with name, if any, else NULL. |
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| 125 | */ |
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| 126 | |||
| 127 | char * |
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| 128 | _DEFUN (_getenv_r, (reent_ptr, name), |
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| 129 | struct _reent *reent_ptr _AND |
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| 130 | _CONST char *name) |
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| 131 | { |
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| 132 | int offset; |
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| 133 | |||
| 9959 | turbocat | 134 | return _findenv_r (reent_ptr, name, &offset); |
| 6099 | serge | 135 | } |