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Edit File: struct_mutex.h

/* x86 internal mutex struct definitions.
   Copyright (C) 2019-2021 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 _THREAD_MUTEX_INTERNAL_H
#define _THREAD_MUTEX_INTERNAL_H 1

struct __pthread_mutex_s
{
  int __lock;
  unsigned int __count;
  int __owner;
#ifdef __x86_64__
  unsigned int __nusers;
#endif
  /* KIND must stay at this position in the structure to maintain
     binary compatibility with static initializers.  */
  int __kind;
#ifdef __x86_64__
  short __spins;
  short __elision;
  __pthread_list_t __list;
# define __PTHREAD_MUTEX_HAVE_PREV      1
#else
  unsigned int __nusers;
  __extension__ union
  {
    struct
    {
      short __espins;
      short __eelision;
# define __spins __elision_data.__espins
# define __elision __elision_data.__eelision
    } __elision_data;
    __pthread_slist_t __list;
  };
# define __PTHREAD_MUTEX_HAVE_PREV      0
#endif
};

#ifdef __x86_64__
# define __PTHREAD_MUTEX_INITIALIZER(__kind) \
  0, 0, 0, 0, __kind, 0, 0, { 0, 0 }
#else
# define __PTHREAD_MUTEX_INITIALIZER(__kind) \
  0, 0, 0, __kind, 0, { { 0, 0 } }
#endif

#endif