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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 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., 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 <sysdep.h>
#define _ERRNO_H
#include <errnos.h>
#ifdef PIC
.section .bss
.align 3
.globl __curbrk
__curbrk: .skip 8
.type __curbrk,@object
.size __curbrk,8
#else
.comm __curbrk, 8
#endif
.text
LEAF(__brk, 8)
ldgp gp, 0(t12)
subq sp, 8, sp
#ifdef PROF
.set noat
lda AT, _mcount
jsr AT, (AT), _mcount
.set at
#endif
.prologue 1
/* Save the requested brk across the system call. */
stq a0, 0(sp)
ldiq v0, __NR_brk
call_pal PAL_callsys
ldq a0, 0(sp)
/* Be prepared for an OSF-style brk. */
bne a3, $err1
beq v0, $ok
/* Correctly handle the brk(0) query case. */
cmoveq a0, v0, a0
xor a0, v0, t0
bne t0, $err0
/* Update __curbrk and return cleanly. */
mov zero, v0
$ok: stq a0, __curbrk
addq sp, 8, sp
ret
/* What a horrible way to die. */
$err0: ldi v0, ENOMEM
$err1: lda pv, __syscall_error
addq sp, 8, sp
jmp zero, (pv), __syscall_error
END(__brk)
weak_alias (__brk, brk)
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