sysdeps/standalone/brk.c

   1 /* Copyright (C) 1991, 1994, 1995, 1997 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Ported to standalone by Joel Sherrill jsherril@redstone-emh2.army.mil,
   4      On-Line Applications Research Corporation.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Library General Public License as
   8    published by the Free Software Foundation; either version 2 of the
   9    License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Library General Public License for more details.
  15
  16    You should have received a copy of the GNU Library General Public
  17    License along with the GNU C Library; see the file COPYING.LIB.  If not,
  18    write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  19    Boston, MA 02111-1307, USA.  */
  20
  21 #include <stdlib.h>
  22
  23 void *__curbrk;
  24 void *__rorig;
  25 void *__rlimit;
  26
  27 int
  28 __brk (inaddr)
  29      void *inaddr;
  30 {
  31
  32   if ( ( (void *)inaddr > (void *)__rlimit ) ||
  33                         ( (void *)inaddr < (void *)__rorig ) )
  34     return -1;
  35
  36   __curbrk = inaddr;
  37   return 0;
  38 }
  39
  40 /* Initialization Code for Memory Allocation */
  41
  42 void *__C_heap_start;
  43 int __C_heap_size;
  44
  45 #ifdef HAVE_GNU_LD
  46 static
  47 #endif
  48 void
  49 __NONE_set_memvals (argc, argv, envp)
  50      int argc;
  51      char **argv;
  52      char **envp;
  53 {
  54
  55   __rorig  =
  56   __curbrk = __C_heap_start;
  57   __rlimit = __curbrk + __C_heap_size;
  58
  59   (void) &__NONE_set_memvals;    /* Avoid "defined but not used" warning.  */
  60 }
  61
  62 #ifdef  HAVE_GNU_LD
  63 text_set_element (__libc_subinit, __NONE_set_memvals);
  64 #endif
  65
  66 weak_alias (__brk, brk)