source: trunk/src/gcc/libiberty/setenv.c@ 1928

/* Copyright (C) 1992, 1995, 1996, 1997, 2002 Free Software Foundation, Inc.
   This file based on setenv.c in the GNU C Library.

   The GNU C Library is free software; you can redistribute it and/or
   modify it under the terms of the GNU Library General Public License as
   published by the Free Software Foundation; either version 2 of the
   License, or (at your option) any later version.

   The GNU C Library is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   Library General Public License for more details.

   You should have received a copy of the GNU Library General Public
   License along with the GNU C Library; see the file COPYING.LIB.  If not,
   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
   Boston, MA 02111-1307, USA.  */


/*

@deftypefn Supplemental int setenv (const char *@var{name}, const char *@var{value}, int @var{overwrite})
@deftypefnx Supplemental void unsetenv (const char *@var{name})

@code{setenv} adds @var{name} to the environment with value
@var{value}.  If the name was already present in the environment,
the new value will be stored only if @var{overwrite} is nonzero.
The companion @code{unsetenv} function removes @var{name} from the
environment.  This implementation is not safe for multithreaded code.

@end deftypefn

*/

#if HAVE_CONFIG_H
# include <config.h>
#endif

#define setenv libiberty_setenv
#define unsetenv libiberty_unsetenv

#include "ansidecl.h"
#include <sys/types.h> /* For `size_t' */
#include <stdio.h>     /* For `NULL' */

#include <errno.h>
#if !defined(errno) && !defined(HAVE_ERRNO_DECL)
extern int errno;
#endif
#define __set_errno(ev) ((errno) = (ev))

#if HAVE_STDLIB_H
# include <stdlib.h>
#endif
#if HAVE_STRING_H
# include <string.h>
#endif
#if HAVE_UNISTD_H
# include <unistd.h>
#endif

#define __environ       environ
#ifndef HAVE_ENVIRON_DECL
extern char **environ;
#endif

#undef setenv
#undef unsetenv

/* LOCK and UNLOCK are defined as no-ops.  This makes the libiberty
 * implementation MT-Unsafe. */
#define LOCK
#define UNLOCK

/* Below this point, it's verbatim code from the glibc-2.0 implementation */

/* If this variable is not a null pointer we allocated the current
   environment.  */
static char **last_environ;


int
setenv (name, value, replace)
     const char *name;
     const char *value;
     int replace;
{
  register char **ep = 0;
  register size_t size;
  const size_t namelen = strlen (name);
  const size_t vallen = strlen (value) + 1;

  LOCK;

  size = 0;
  if (__environ != NULL)
    {
      for (ep = __environ; *ep != NULL; ++ep)
        if (!strncmp (*ep, name, namelen) && (*ep)[namelen] == '=')
          break;
        else
          ++size;