gthr.h

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/* Threads compatibility routines for libgcc2.  */
/* Compile this one with gcc.  */
/* Copyright (C) 1997, 1998, 2004 Free Software Foundation, Inc.

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free
Software Foundation; either version 2, or (at your option) any later
version.

GCC 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 General Public License
for more details.

You should have received a copy of the GNU General Public License
along with GCC; see the file COPYING.  If not, write to the Free
Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
02110-1301, USA.  */

/* As a special exception, if you link this library with other files,
   some of which are compiled with GCC, to produce an executable,
   this library does not by itself cause the resulting executable
   to be covered by the GNU General Public License.
   This exception does not however invalidate any other reasons why
   the executable file might be covered by the GNU General Public License.  */

#ifndef _GLIBCXX_GCC_GTHR_H
#define _GLIBCXX_GCC_GTHR_H

#ifndef _GLIBCXX_HIDE_EXPORTS
#pragma GCC visibility push(default)
#endif

/* If this file is compiled with threads support, it must
       #define __GTHREADS 1
   to indicate that threads support is present.  Also it has define
   function
     int __gthread_active_p ()
   that returns 1 if thread system is active, 0 if not.

   The threads interface must define the following types:
     __gthread_key_t
     __gthread_once_t
     __gthread_mutex_t
     __gthread_recursive_mutex_t

   The threads interface must define the following macros:

     __GTHREAD_ONCE_INIT
            to initialize __gthread_once_t
     __GTHREAD_MUTEX_INIT
            to initialize __gthread_mutex_t to get a fast
        non-recursive mutex.
     __GTHREAD_MUTEX_INIT_FUNCTION
            some systems can't initialize a mutex without a
        function call.  On such systems, define this to a
        function which looks like this:
          void __GTHREAD_MUTEX_INIT_FUNCTION (__gthread_mutex_t *)
        Don't define __GTHREAD_MUTEX_INIT in this case
     __GTHREAD_RECURSIVE_MUTEX_INIT
     __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION
            as above, but for a recursive mutex.

   The threads interface must define the following static functions:

     int __gthread_once (__gthread_once_t *once, void (*func) ())

     int __gthread_key_create (__gthread_key_t *keyp, void (*dtor) (void *))
     int __gthread_key_delete (__gthread_key_t key)

     void *__gthread_getspecific (__gthread_key_t key)
     int __gthread_setspecific (__gthread_key_t key, const void *ptr)

     int __gthread_mutex_lock (__gthread_mutex_t *mutex);
     int __gthread_mutex_trylock (__gthread_mutex_t *mutex);
     int __gthread_mutex_unlock (__gthread_mutex_t *mutex);

     int __gthread_recursive_mutex_lock (__gthread_recursive_mutex_t *mutex);
     int __gthread_recursive_mutex_trylock (__gthread_recursive_mutex_t *mutex);
     int __gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *mutex);

   The following are supported in POSIX threads only. They are required to
   fix a deadlock in static initialization inside libsupc++. The header file
   gthr-posix.h defines a symbol __GTHREAD_HAS_COND to signify that these extra
   features are supported.

   Types:
     __gthread_cond_t

   Macros:
     __GTHREAD_COND_INIT
     __GTHREAD_COND_INIT_FUNCTION

   Interface:
     int __gthread_cond_broadcast (__gthread_cond_t *cond);
     int __gthread_cond_wait (__gthread_cond_t *cond, __gthread_mutex_t *mutex);
     int __gthread_cond_wait_recursive (__gthread_cond_t *cond,
                    __gthread_recursive_mutex_t *mutex);

   All functions returning int should return zero on success or the error
   number.  If the operation is not supported, -1 is returned.

   Currently supported threads packages are
     TPF threads with -D__tpf__
     POSIX/Unix98 threads with -D_PTHREADS
     POSIX/Unix95 threads with -D_PTHREADS95
     DCE threads with -D_DCE_THREADS
     Solaris/UI threads with -D_SOLARIS_THREADS
*/

/* Check first for thread specific defines.  */
#if defined (_GLIBCXX___tpf_GLIBCXX___)
#include <bits/gthr-tpf.h>
#elif _GLIBCXX__PTHREADS
#include <bits/gthr-posix.h>
#elif _GLIBCXX__PTHREADS95
#include <bits/gthr-posix95.h>
#elif _GLIBCXX__DCE_THREADS
#include <bits/gthr-dce.h>
#elif _GLIBCXX__SOLARIS_THREADS
#include <bits/gthr-solaris.h>

/* Include GTHREAD_FILE if one is defined.  */
#elif defined(_GLIBCXX_HAVE_GTHR_DEFAULT)
#if __GXX_WEAK__
#ifndef _GLIBCXX_GTHREAD_USE_WEAK
#define _GLIBCXX_GTHREAD_USE_WEAK 1
#endif
#endif
#include <bits/gthr-default.h>

/* Fallback to single thread definitions.  */
#else
#include <bits/gthr-single.h>
#endif

#ifndef _GLIBCXX_HIDE_EXPORTS
#pragma GCC visibility pop
#endif

#endif /* ! _GLIBCXX_GCC_GTHR_H */

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