| 1 | /* Copyright (C) 1992, 1995, 1996, 1997, 2002, 2011 Free Software Foundation, |
| 2 | Inc. |
| 3 | This file based on setenv.c in the GNU C Library. |
| 4 | |
| 5 | The GNU C Library is free software; you can redistribute it and/or |
| 6 | modify it under the terms of the GNU Library General Public License as |
| 7 | published by the Free Software Foundation; either version 2 of the |
| 8 | License, or (at your option) any later version. |
| 9 | |
| 10 | The GNU C Library is distributed in the hope that it will be useful, |
| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | Library General Public License for more details. |
| 14 | |
| 15 | You should have received a copy of the GNU Library General Public |
| 16 | License along with the GNU C Library; see the file COPYING.LIB. If not, |
| 17 | write to the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor, |
| 18 | Boston, MA 02110-1301, USA. */ |
| 19 | |
| 20 | |
| 21 | /* |
| 22 | |
| 23 | @deftypefn Supplemental int setenv (const char *@var{name}, @ |
| 24 | const char *@var{value}, int @var{overwrite}) |
| 25 | @deftypefnx Supplemental void unsetenv (const char *@var{name}) |
| 26 | |
| 27 | @code{setenv} adds @var{name} to the environment with value |
| 28 | @var{value}. If the name was already present in the environment, |
| 29 | the new value will be stored only if @var{overwrite} is nonzero. |
| 30 | The companion @code{unsetenv} function removes @var{name} from the |
| 31 | environment. This implementation is not safe for multithreaded code. |
| 32 | |
| 33 | @end deftypefn |
| 34 | |
| 35 | */ |
| 36 | |
| 37 | #if HAVE_CONFIG_H |
| 38 | # include <config.h> |
| 39 | #endif |
| 40 | |
| 41 | #define setenv libiberty_setenv |
| 42 | #define unsetenv libiberty_unsetenv |
| 43 | |
| 44 | #include "ansidecl.h" |
| 45 | #include <sys/types.h> /* For `size_t' */ |
| 46 | #include <stdio.h> /* For `NULL' */ |
| 47 | |
| 48 | #include <errno.h> |
| 49 | #if !defined(errno) && !defined(HAVE_ERRNO_DECL) |
| 50 | extern int errno; |
| 51 | #endif |
| 52 | #define __set_errno(ev) ((errno) = (ev)) |
| 53 | |
| 54 | #if HAVE_STDLIB_H |
| 55 | # include <stdlib.h> |
| 56 | #endif |
| 57 | #if HAVE_STRING_H |
| 58 | # include <string.h> |
| 59 | #endif |
| 60 | #if HAVE_UNISTD_H |
| 61 | # include <unistd.h> |
| 62 | #endif |
| 63 | |
| 64 | #define __environ environ |
| 65 | #ifndef HAVE_ENVIRON_DECL |
| 66 | extern char **environ; |
| 67 | #endif |
| 68 | |
| 69 | #undef setenv |
| 70 | #undef unsetenv |
| 71 | |
| 72 | /* LOCK and UNLOCK are defined as no-ops. This makes the libiberty |
| 73 | * implementation MT-Unsafe. */ |
| 74 | #define LOCK |
| 75 | #define UNLOCK |
| 76 | |
| 77 | /* Below this point, it's verbatim code from the glibc-2.0 implementation */ |
| 78 | |
| 79 | /* If this variable is not a null pointer we allocated the current |
| 80 | environment. */ |
| 81 | static char **last_environ; |
| 82 | |
| 83 | |
| 84 | int |
| 85 | setenv (const char *name, const char *value, int replace) |
| 86 | { |
| 87 | register char **ep = 0; |
| 88 | register size_t size; |
| 89 | const size_t namelen = strlen (name); |
| 90 | const size_t vallen = strlen (value) + 1; |
| 91 | |
| 92 | LOCK; |
| 93 | |
| 94 | size = 0; |
| 95 | if (__environ != NULL) |
| 96 | { |
| 97 | for (ep = __environ; *ep != NULL; ++ep) |
| 98 | if (!strncmp (*ep, name, namelen) && (*ep)[namelen] == '=') |
| 99 | break; |
| 100 | else |
| 101 | ++size; |
| 102 | } |
| 103 | |
| 104 | if (__environ == NULL || *ep == NULL) |
| 105 | { |
| 106 | char **new_environ; |
| 107 | if (__environ == last_environ && __environ != NULL) |
| 108 | /* We allocated this space; we can extend it. */ |
| 109 | new_environ = (char **) realloc (last_environ, |
| 110 | (size + 2) * sizeof (char *)); |
| 111 | else |
| 112 | new_environ = (char **) malloc ((size + 2) * sizeof (char *)); |
| 113 | |
| 114 | if (new_environ == NULL) |
| 115 | { |
| 116 | UNLOCK; |
| 117 | return -1; |
| 118 | } |
| 119 | |
| 120 | new_environ[size] = (char *) malloc (namelen + 1 + vallen); |
| 121 | if (new_environ[size] == NULL) |
| 122 | { |
| 123 | free ((char *) new_environ); |
| 124 | __set_errno (ENOMEM); |
| 125 | UNLOCK; |
| 126 | return -1; |
| 127 | } |
| 128 | |
| 129 | if (__environ != last_environ) |
| 130 | memcpy ((char *) new_environ, (char *) __environ, |
| 131 | size * sizeof (char *)); |
| 132 | |
| 133 | memcpy (new_environ[size], name, namelen); |
| 134 | new_environ[size][namelen] = '='; |
| 135 | memcpy (&new_environ[size][namelen + 1], value, vallen); |
| 136 | |
| 137 | new_environ[size + 1] = NULL; |
| 138 | |
| 139 | last_environ = __environ = new_environ; |
| 140 | } |
| 141 | else if (replace) |
| 142 | { |
| 143 | size_t len = strlen (*ep); |
| 144 | if (len + 1 < namelen + 1 + vallen) |
| 145 | { |
| 146 | /* The existing string is too short; malloc a new one. */ |
| 147 | char *new_string = (char *) malloc (namelen + 1 + vallen); |
| 148 | if (new_string == NULL) |
| 149 | { |
| 150 | UNLOCK; |
| 151 | return -1; |
| 152 | } |
| 153 | *ep = new_string; |
| 154 | } |
| 155 | memcpy (*ep, name, namelen); |
| 156 | (*ep)[namelen] = '='; |
| 157 | memcpy (&(*ep)[namelen + 1], value, vallen); |
| 158 | } |
| 159 | |
| 160 | UNLOCK; |
| 161 | |
| 162 | return 0; |
| 163 | } |
| 164 | |
| 165 | void |
| 166 | unsetenv (const char *name) |
| 167 | { |
| 168 | const size_t len = strlen (name); |
| 169 | char **ep; |
| 170 | |
| 171 | LOCK; |
| 172 | |
| 173 | for (ep = __environ; *ep; ++ep) |
| 174 | if (!strncmp (*ep, name, len) && (*ep)[len] == '=') |
| 175 | { |
| 176 | /* Found it. Remove this pointer by moving later ones back. */ |
| 177 | char **dp = ep; |
| 178 | do |
| 179 | dp[0] = dp[1]; |
| 180 | while (*dp++); |
| 181 | /* Continue the loop in case NAME appears again. */ |
| 182 | } |
| 183 | |
| 184 | UNLOCK; |
| 185 | } |