glibc/sysdeps/unix/sysv/linux/i386/brk.c
Ulrich Drepper f051627fad Update.
2002-12-18  Ulrich Drepper  <drepper@redhat.com>

	* sysdeps/unix/sysv/linux/i386/sysdep.h: Define ENTER_KERNEL macro.
	Use it instead of directly int $0x80.
	* sysdeps/unix/sysv/linux/i386/brk.c: Use ENTER_KERNEL.
	* sysdeps/unix/sysv/linux/i386/mmap64.S: Likewise.
	* sysdeps/unix/sysv/linux/i386/mmap.S: Likewise.
	* sysdeps/unix/sysv/linux/i386/sigaction.c: Likewise.
	* sysdeps/unix/sysv/linux/i386/socket.S: Likewise.
	* sysdeps/unix/sysv/linux/i386/syscall.S: Likewise.
2002-12-18 11:56:21 +00:00

57 lines
1.8 KiB
C

/* brk system call for Linux/i386.
Copyright (C) 1995, 1996, 2000, 2002 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 <sysdep.h>
#include <bp-checks.h>
/* This must be initialized data because commons can't have aliases. */
void *__curbrk = 0;
/* Old braindamage in GCC's crtstuff.c requires this symbol in an attempt
to work around different old braindamage in the old Linux ELF dynamic
linker. */
weak_alias (__curbrk, ___brk_addr)
int
__brk (void *addr)
{
void *__unbounded newbrk, *__unbounded scratch;
asm ("movl %%ebx, %1\n\t" /* Save %ebx in scratch register. */
"movl %3, %%ebx\n\t" /* Put ADDR in %ebx to be syscall arg. */
ENTER_KERNEL "\n\t" /* Perform the system call. */
"movl %1, %%ebx" /* Restore %ebx from scratch register. */
: "=a" (newbrk), "=r" (scratch)
: "0" (SYS_ify (brk)), "g" (__ptrvalue (addr)));
__curbrk = newbrk;
if (newbrk < addr)
{
__set_errno (ENOMEM);
return -1;
}
return 0;
}
weak_alias (__brk, brk)