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/* HPPA internal rwlock struct definitions.
Copyright (C) 2019-2023 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, see
<http://www.gnu.org/licenses/>. */
#ifndef _RWLOCK_INTERNAL_H
#define _RWLOCK_INTERNAL_H
struct __pthread_rwlock_arch_t
{
/* In the old Linuxthreads pthread_rwlock_t, this is the
start of the 4-word 16-byte aligned lock structure. The
next four words are all set to 1 by the Linuxthreads
PTHREAD_RWLOCK_INITIALIZER. We ignore them in NPTL.
The 16-byte aligned lock stucture is not needed for NPTL.
It causes some package builds to fail (e.g., protobuf) and
issues with dynamic memory allocation in C++ versions prior
to C++17. Removing it allows for more efficient allocators
and better compatibility with other architectures. */
int __compat_padding[4];
unsigned int __readers;
unsigned int __writers;
unsigned int __wrphase_futex;
unsigned int __writers_futex;
unsigned int __pad3;
unsigned int __pad4;
int __cur_writer;
/* An unused word, reserved for future use. It was added
to maintain the location of the flags from the Linuxthreads
layout of this structure. */
int __reserved1;
/* FLAGS must stay at this position in the structure to maintain
binary compatibility. */
unsigned char __pad2;
unsigned char __pad1;
unsigned char __shared;
unsigned char __flags;
/* The NPTL pthread_rwlock_t is 4 words smaller than the
Linuxthreads version. One word is in the middle of the
structure, the other three are at the end. */
int __reserved2;
int __reserved3;
int __reserved4;
};
#define __PTHREAD_RWLOCK_INITIALIZER(__flags) \
{ 0, 0, 0, 0 }, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, __flags, 0, 0, 0
#endif
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