libiberty/putenv.c

   1 /* Copyright (C) 1991, 1994, 1995, 1996 Free Software Foundation, Inc.
   2    This file based on putenv.c in the GNU C Library.
   3
   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.
   8
   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.
  13
  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.  */
  18
  19 #if defined (_AIX) && !defined (__GNUC__)
  20  #pragma alloca
  21 #endif
  22
  23 #if HAVE_CONFIG_H
  24 # include <config.h>
  25 #endif
  26
  27 #include "ansidecl.h"
  28
  29 #if HAVE_STDLIB_H
  30 # include <stdlib.h>
  31 #endif
  32 #if HAVE_STRING_H
  33 # include <string.h>
  34 #endif
  35
  36 #ifdef HAVE_ALLOCA_H
  37 # include <alloca.h>
  38 #else
  39 # ifndef alloca
  40 #  ifdef __GNUC__
  41 #   define alloca __builtin_alloca
  42 #  else
  43 extern char *alloca ();
  44 #  endif /* __GNUC__ */
  45 # endif /* alloca */
  46 #endif /* HAVE_ALLOCA_H */
  47
  48 /* Below this point, it's verbatim code from the glibc-2.0 implementation */
  49
  50
  51 /* Put STRING, which is of the form "NAME=VALUE", in the environment.  */
  52 int
  53 putenv (string)
  54      const char *string;
  55 {
  56   const char *const name_end = strchr (string, '=');
  57
  58   if (name_end)
  59     {
  60       char *name = (char *) alloca (name_end - string + 1);
  61       memcpy (name, string, name_end - string);
  62       name[name_end - string] = '\0';
  63       return setenv (name, name_end + 1, 1);
  64     }
  65
  66   unsetenv (string);
  67   return 0;
  68 }