1 /* Copyright (C) 1992, 1995, 1996, 1997, 2002 Free Software Foundation, Inc.
2 This file based on setenv.c in the GNU C Library.
4 The GNU C Library is free software; you can redistribute it and/or
5 modify it under the terms of the GNU Library General Public License as
6 published by the Free Software Foundation; either version 2 of the
7 License, or (at your option) any later version.
9 The GNU C Library is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 Library General Public License for more details.
14 You should have received a copy of the GNU Library General Public
15 License along with the GNU C Library; see the file COPYING.LIB. If not,
16 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
17 Boston, MA 02111-1307, USA. */
22 @deftypefn Supplemental int setenv (const char *@var{name}, const char *@var{value}, int @var{overwrite})
23 @deftypefnx Supplemental void unsetenv (const char *@var{name})
25 @code{setenv} adds @var{name} to the environment with value
26 @var{value}. If the name was already present in the environment,
27 the new value will be stored only if @var{overwrite} is nonzero.
28 The companion @code{unsetenv} function removes @var{name} from the
29 environment. This implementation is not safe for multithreaded code.
39 #define setenv libiberty_setenv
40 #define unsetenv libiberty_unsetenv
43 #include <sys/types.h> /* For `size_t' */
44 #include <stdio.h> /* For `NULL' */
47 #if !defined(errno) && !defined(HAVE_ERRNO_DECL)
50 #define __set_errno(ev) ((errno) = (ev))
62 #define __environ environ
63 #ifndef HAVE_ENVIRON_DECL
64 extern char **environ;
70 /* LOCK and UNLOCK are defined as no-ops. This makes the libiberty
71 * implementation MT-Unsafe. */
75 /* Below this point, it's verbatim code from the glibc-2.0 implementation */
77 /* If this variable is not a null pointer we allocated the current
79 static char **last_environ;
83 setenv (name, value, replace)
88 register char **ep = 0;
90 const size_t namelen = strlen (name);
91 const size_t vallen = strlen (value) + 1;
96 if (__environ != NULL)
98 for (ep = __environ; *ep != NULL; ++ep)
99 if (!strncmp (*ep, name, namelen) && (*ep)[namelen] == '=')
105 if (__environ == NULL || *ep == NULL)
108 if (__environ == last_environ && __environ != NULL)
109 /* We allocated this space; we can extend it. */
110 new_environ = (char **) realloc (last_environ,
111 (size + 2) * sizeof (char *));
113 new_environ = (char **) malloc ((size + 2) * sizeof (char *));
115 if (new_environ == NULL)
121 new_environ[size] = malloc (namelen + 1 + vallen);
122 if (new_environ[size] == NULL)
124 free ((char *) new_environ);
125 __set_errno (ENOMEM);
130 if (__environ != last_environ)
131 memcpy ((char *) new_environ, (char *) __environ,
132 size * sizeof (char *));
134 memcpy (new_environ[size], name, namelen);
135 new_environ[size][namelen] = '=';
136 memcpy (&new_environ[size][namelen + 1], value, vallen);
138 new_environ[size + 1] = NULL;
140 last_environ = __environ = new_environ;
144 size_t len = strlen (*ep);
145 if (len + 1 < namelen + 1 + vallen)
147 /* The existing string is too short; malloc a new one. */
148 char *new = malloc (namelen + 1 + vallen);
156 memcpy (*ep, name, namelen);
157 (*ep)[namelen] = '=';
158 memcpy (&(*ep)[namelen + 1], value, vallen);
170 const size_t len = strlen (name);
175 for (ep = __environ; *ep; ++ep)
176 if (!strncmp (*ep, name, len) && (*ep)[len] == '=')
178 /* Found it. Remove this pointer by moving later ones back. */
183 /* Continue the loop in case NAME appears again. */