// Support for concurrent programing -*- C++ -*-// Copyright (C) 2003, 2004// Free Software Foundation, Inc.//// This file is part of the GNU ISO C++ Library.  This library 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.// This 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 General Public License for more details.// You should have received a copy of the GNU General Public License along// with this library; see the file COPYING.  If not, write to the Free// Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,// USA.// As a special exception, you may use this file as part of a free software// library without restriction.  Specifically, if other files instantiate// templates or use macros or inline functions from this file, or you compile// this file and link it with other files to produce an executable, this// file 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 _CONCURRENCE_H#define _CONCURRENCE_H 1// GCC's thread abstraction layer#include "bits/gthr.h"#if __GTHREADS# ifdef __GTHREAD_MUTEX_INIT#  define __glibcxx_mutex_type __gthread_mutex_t#  define __glibcxx_mutex_define_initialized(NAME) \__gthread_mutex_t NAME = __GTHREAD_MUTEX_INIT#  define __glibcxx_mutex_lock(NAME) \__gthread_mutex_lock(&NAME)# else// Implies __GTHREAD_MUTEX_INIT_FUNCTIONstruct __glibcxx_mutex : public __gthread_mutex_t{   __glibcxx_mutex() { __GTHREAD_MUTEX_INIT_FUNCTION(this); }};#  define __glibcxx_mutex_type __glibcxx_mutex#  define __glibcxx_mutex_define_initialized(NAME) \__glibcxx_mutex NAME# define __glibcxx_mutex_lock(NAME) \__gthread_mutex_lock(&NAME)# endif# define __glibcxx_mutex_unlock(NAME) __gthread_mutex_unlock(&NAME)#else# define __glibcxx_mutex_type __gthread_mutex_t# define __glibcxx_mutex_define_initialized(NAME) __gthread_mutex_t NAME# define __glibcxx_mutex_lock(NAME)# define __glibcxx_mutex_unlock(NAME)#endifnamespace __gnu_cxx{  typedef __glibcxx_mutex_type mutex_type;    // Scoped lock idiom.  // Acquire the mutex here with a constructor call, then release with  // the destructor call in accordance with RAII style.   class lock  {    // Externally defined and initialized.    mutex_type& device;  public:    explicit lock(mutex_type& name) : device(name)    { __glibcxx_mutex_lock(device); }    ~lock() throw()    { __glibcxx_mutex_unlock(device); }  private:    lock(const lock&);    lock& operator=(const lock&);  };}#endif