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/* brk system call for Linux/i386.
Copyright (C) 1995, 1996, 2000 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 Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <errno.h>
#include <unistd.h>
#include <sys/syscall.h>
/* This must be initialized data because commons can't have aliases. */
void *__curbrk = 0;
int brk (void *addr)
{
void *__unbounded newbrk, *__unbounded scratch;
asm ("movl %%ebx, %1\n" /* Save %ebx in scratch register. */
"movl %3, %%ebx\n" /* Put ADDR in %ebx to be syscall arg. */
"int $0x80 # %2\n" /* Perform the system call. */
"movl %1, %%ebx\n" /* Restore %ebx from scratch register. */
: "=a" (newbrk), "=r" (scratch)
: "0" (__NR_brk), "g" (__ptrvalue (addr)));
__curbrk = newbrk;
if (newbrk < addr)
{
__set_errno (ENOMEM);
return -1;
}
return 0;
}
libc_hidden_proto(brk)
libc_hidden_def(brk)
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