glibc/sysdeps/mach/hurd/sbrk.c
1995-02-18 01:27:10 +00:00

43 lines
1.4 KiB
C

/* Copyright (C) 1991, 1994, 1995 Free Software Foundation, Inc.
This file is part of 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., 675 Mass Ave,
Cambridge, MA 02139, USA. */
#include <ansidecl.h>
#include <errno.h>
#include <hurd.h>
/* Extend the process's data space by INCREMENT.
If INCREMENT is negative, shrink data space by - INCREMENT.
Return the address of the start of the new data space, or -1 for errors. */
PTR
DEFUN(__sbrk, (increment), int increment)
{
PTR result;
HURD_CRITICAL_BEGIN;
__mutex_lock (&_hurd_brk_lock);
result = (PTR) _hurd_brk;
if (increment != 0 && _hurd_set_brk (_hurd_brk + increment) < 0)
result = (PTR) -1;
__mutex_unlock (&_hurd_brk_lock);
HURD_CRITICAL_END;
return result;
}
weak_alias (__sbrk, sbrk)