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/* Copyright (C) 1993-2019 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, see
<http://www.gnu.org/licenses/>. */
/* __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 <bits/errno.h>
#ifdef PIC
.section .bss
.align 3
.globl __curbrk
__curbrk: .skip 8
.type __curbrk,@object
.size __curbrk,8
#else
.comm __curbrk, 8
#endif
.text
.align 4
.globl __brk
.ent __brk
.usepv __brk, std
cfi_startproc
__brk:
ldgp gp, 0(t12)
subq sp, 16, sp
cfi_adjust_cfa_offset (16)
#ifdef PROF
.set noat
lda AT, _mcount
jsr AT, (AT), _mcount
.set at
#endif
/* Save the requested brk across the system call. */
stq a0, 0(sp)
ldiq v0, __NR_brk
call_pal PAL_callsys
ldq a0, 0(sp)
addq sp, 16, sp
cfi_adjust_cfa_offset (-16)
/* Be prepared for an OSF-style brk. */
bne a3, SYSCALL_ERROR_LABEL
beq v0, $ok
/* Correctly handle the brk(0) query case. */
cmoveq a0, v0, a0
xor a0, v0, t0
lda v0, ENOMEM
bne t0, SYSCALL_ERROR_LABEL
/* Update __curbrk and return cleanly. */
lda v0, 0
$ok: stq a0, __curbrk
ret
PSEUDO_END(__brk)
cfi_endproc
weak_alias (__brk, brk)
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