mingw/include/c++/3.4.2/bits/concurrence.h

   1 // Support for concurrent programing -*- C++ -*-
   2
   3 // Copyright (C) 2003, 2004
   4 // Free Software Foundation, Inc.
   5 //
   6 // This file is part of the GNU ISO C++ Library.  This library is free
   7 // software; you can redistribute it and/or modify it under the
   8 // terms of the GNU General Public License as published by the
   9 // Free Software Foundation; either version 2, or (at your option)
  10 // any later version.
  11
  12 // This library is distributed in the hope that it will be useful,
  13 // but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 // GNU General Public License for more details.
  16
  17 // You should have received a copy of the GNU General Public License along
  18 // with this library; see the file COPYING.  If not, write to the Free
  19 // Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307,
  20 // USA.
  21
  22 // As a special exception, you may use this file as part of a free software
  23 // library without restriction.  Specifically, if other files instantiate
  24 // templates or use macros or inline functions from this file, or you compile
  25 // this file and link it with other files to produce an executable, this
  26 // file does not by itself cause the resulting executable to be covered by
  27 // the GNU General Public License.  This exception does not however
  28 // invalidate any other reasons why the executable file might be covered by
  29 // the GNU General Public License.
  30
  31 #ifndef _CONCURRENCE_H
  32 #define _CONCURRENCE_H 1
  33
  34 // GCC's thread abstraction layer
  35 #include "bits/gthr.h"
  36
  37 #if __GTHREADS
  38
  39 # ifdef __GTHREAD_MUTEX_INIT
  40 #  define __glibcxx_mutex_type __gthread_mutex_t
  41 #  define __glibcxx_mutex_define_initialized(NAME) \
  42 __gthread_mutex_t NAME = __GTHREAD_MUTEX_INIT
  43 #  define __glibcxx_mutex_lock(NAME) \
  44 __gthread_mutex_lock(&NAME)
  45 # else
  46 // Implies __GTHREAD_MUTEX_INIT_FUNCTION
  47 struct __glibcxx_mutex : public __gthread_mutex_t
  48 {
  49    __glibcxx_mutex() { __GTHREAD_MUTEX_INIT_FUNCTION(this); }
  50 };
  51
  52 #  define __glibcxx_mutex_type __glibcxx_mutex
  53 #  define __glibcxx_mutex_define_initialized(NAME) \
  54 __glibcxx_mutex NAME
  55 # define __glibcxx_mutex_lock(NAME) \
  56 __gthread_mutex_lock(&NAME)
  57 # endif
  58
  59 # define __glibcxx_mutex_unlock(NAME) __gthread_mutex_unlock(&NAME)
  60
  61 #else
  62
  63 # define __glibcxx_mutex_type __gthread_mutex_t
  64 # define __glibcxx_mutex_define_initialized(NAME) __gthread_mutex_t NAME
  65 # define __glibcxx_mutex_lock(NAME)
  66 # define __glibcxx_mutex_unlock(NAME)
  67
  68 #endif
  69
  70 namespace __gnu_cxx
  71 {
  72   typedef __glibcxx_mutex_type mutex_type;
  73
  74   // Scoped lock idiom.
  75   // Acquire the mutex here with a constructor call, then release with
  76   // the destructor call in accordance with RAII style.
  77    class lock
  78   {
  79     // Externally defined and initialized.
  80     mutex_type& device;
  81
  82   public:
  83     explicit lock(mutex_type& name) : device(name)
  84     { __glibcxx_mutex_lock(device); }
  85
  86     ~lock() throw()
  87     { __glibcxx_mutex_unlock(device); }
  88
  89   private:
  90     lock(const lock&);
  91     lock& operator=(const lock&);
  92   };
  93 }
  94
  95 #endif