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/* Copyright (C) 1993, 1995, 1996, 1997 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Brendan Kehoe <brendan@zen.org>, 1993.
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. */
/* __brk is a special syscall under Linux since it never returns an
error. Instead, the error condition is indicated by returning the old
break value (instead of the new, requested one). */
#include <features.h>
#define _ERRNO_H
#include <bits/errno.h>
#include <sys/syscall.h>
#ifdef __PIC__
.section .bss
.align 3
.globl __curbrk
__curbrk: .skip 8
.type __curbrk,@object
.size __curbrk,8
#else
.comm __curbrk, 8
#endif
libc_hidden_data_def(__curbrk)
.text
.globl brk;
.align 3;
.ent brk , 0;
brk:
.frame $30 , 8 , $26
ldgp $29, 0($27)
subq $30, 8, $30
.prologue 1
/* Save the requested brk across the system call. */
stq $16, 0($30)
ldiq $0, __NR_brk
call_pal 131
ldq $16, 0($30)
/* Be prepared for an OSF-style brk. */
bne $19, $err1
beq $0, $ok
/* Correctly handle the brk(0) query case. */
cmoveq $16, $0, $16
xor $16, $0, $1
bne $1, $err0
/* Update __curbrk and return cleanly. */
mov $31, $0
$ok: stq $16, HIDDEN_JUMPTARGET(__curbrk)
addq $30, 8, $30
ret
/* What a horrible way to die. */
$err0: ldi $0, ENOMEM
$err1: addq $30, 8, $30
jmp $31, __syscall_error
.end brk
libc_hidden_def(brk)
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