pthread 的几个结构体

/* Copyright (C) 2002,2003,2004,2005,2006,2007 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.

   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.  */

#ifndef _BITS_PTHREADTYPES_H
#define _BITS_PTHREADTYPES_H    1

#include <bits/wordsize.h>

#if __WORDSIZE == 64
# define __SIZEOF_PTHREAD_ATTR_T 56
# define __SIZEOF_PTHREAD_MUTEX_T 40
# define __SIZEOF_PTHREAD_MUTEXATTR_T 4
# define __SIZEOF_PTHREAD_COND_T 48
# define __SIZEOF_PTHREAD_CONDATTR_T 4
# define __SIZEOF_PTHREAD_RWLOCK_T 56
# define __SIZEOF_PTHREAD_RWLOCKATTR_T 8
# define __SIZEOF_PTHREAD_BARRIER_T 32
# define __SIZEOF_PTHREAD_BARRIERATTR_T 4
#else
# define __SIZEOF_PTHREAD_ATTR_T 36
# define __SIZEOF_PTHREAD_MUTEX_T 24
# define __SIZEOF_PTHREAD_MUTEXATTR_T 4
# define __SIZEOF_PTHREAD_COND_T 48
# define __SIZEOF_PTHREAD_CONDATTR_T 4
# define __SIZEOF_PTHREAD_RWLOCK_T 32
# define __SIZEOF_PTHREAD_RWLOCKATTR_T 8
# define __SIZEOF_PTHREAD_BARRIER_T 20
# define __SIZEOF_PTHREAD_BARRIERATTR_T 4
#endif


/* Thread identifiers.  The structure of the attribute type is not
   exposed on purpose.  */
typedef unsigned long int pthread_t;


typedef union
{
  char __size[__SIZEOF_PTHREAD_ATTR_T];
  long int __align;
} pthread_attr_t;


#if __WORDSIZE == 64
typedef struct __pthread_internal_list
{
  struct __pthread_internal_list *__prev;
  struct __pthread_internal_list *__next;
} __pthread_list_t;
#else
typedef struct __pthread_internal_slist
{
  struct __pthread_internal_slist *__next;
} __pthread_slist_t;
#endif


/* Data structures for mutex handling.  The structure of the attribute
   type is not exposed on purpose.  */
typedef union
{
  struct __pthread_mutex_s
  {
    int __lock;
    unsigned int __count;
    int __owner;
#if __WORDSIZE == 64
    unsigned int __nusers;
#endif
    /* KIND must stay at this position in the structure to maintain
       binary compatibility.  */
    int __kind;
#if __WORDSIZE == 64
    int __spins;
    __pthread_list_t __list;
# define __PTHREAD_MUTEX_HAVE_PREV    1
#else
    unsigned int __nusers;
    __extension__ union
    {
      int __spins;
      __pthread_slist_t __list;
    };
#endif
  } __data;
  char __size[__SIZEOF_PTHREAD_MUTEX_T];
  long int __align;
} pthread_mutex_t;

typedef union
{
  char __size[__SIZEOF_PTHREAD_MUTEXATTR_T];
  int __align;
} pthread_mutexattr_t;


/* Data structure for conditional variable handling.  The structure of
   the attribute type is not exposed on purpose.  */
typedef union
{
  struct
  {
    int __lock;
    unsigned int __futex;
    __extension__ unsigned long long int __total_seq;
    __extension__ unsigned long long int __wakeup_seq;
    __extension__ unsigned long long int __woken_seq;
    void *__mutex;
    unsigned int __nwaiters;
    unsigned int __broadcast_seq;
  } __data;
  char __size[__SIZEOF_PTHREAD_COND_T];
  __extension__ long long int __align;
} pthread_cond_t;

typedef union
{
  char __size[__SIZEOF_PTHREAD_CONDATTR_T];
  int __align;
} pthread_condattr_t;


/* Keys for thread-specific data */
typedef unsigned int pthread_key_t;


/* Once-only execution */
typedef int pthread_once_t;


#if defined __USE_UNIX98 || defined __USE_XOPEN2K
/* Data structure for read-write lock variable handling.  The
   structure of the attribute type is not exposed on purpose.  */
typedef union
{
# if __WORDSIZE == 64
  struct
  {
    int __lock;
    unsigned int __nr_readers;
    unsigned int __readers_wakeup;
    unsigned int __writer_wakeup;
    unsigned int __nr_readers_queued;
    unsigned int __nr_writers_queued;
    int __writer;
    int __shared;
    unsigned long int __pad1;
    unsigned long int __pad2;
    /* FLAGS must stay at this position in the structure to maintain
       binary compatibility.  */
    unsigned int __flags;
  } __data;
# else
  struct
  {
    int __lock;
    unsigned int __nr_readers;
    unsigned int __readers_wakeup;
    unsigned int __writer_wakeup;
    unsigned int __nr_readers_queued;
    unsigned int __nr_writers_queued;
    /* FLAGS must stay at this position in the structure to maintain
       binary compatibility.  */
    unsigned char __flags;
    unsigned char __shared;
    unsigned char __pad1;
    unsigned char __pad2;
    int __writer;
  } __data;
# endif
  char __size[__SIZEOF_PTHREAD_RWLOCK_T];
  long int __align;
} pthread_rwlock_t;

typedef union
{
  char __size[__SIZEOF_PTHREAD_RWLOCKATTR_T];
  long int __align;
} pthread_rwlockattr_t;
#endif


#ifdef __USE_XOPEN2K
/* POSIX spinlock data type.  */
typedef volatile int pthread_spinlock_t;


/* POSIX barriers data type.  The structure of the type is
   deliberately not exposed.  */
typedef union
{
  char __size[__SIZEOF_PTHREAD_BARRIER_T];
  long int __align;
} pthread_barrier_t;

typedef union
{
  char __size[__SIZEOF_PTHREAD_BARRIERATTR_T];
  int __align;
} pthread_barrierattr_t;
#endif


#if __WORDSIZE == 32
/* Extra attributes for the cleanup functions.  */
# define __cleanup_fct_attribute __attribute__ ((__regparm__ (1)))
#endif

#endif    /* bits/pthreadtypes.h */

这些结构体的是在 /usr/include/bits/pthreadtypes.h 中定义。