+++ /dev/null
-// Threading support -*- C++ -*-
-
-// Copyright (C) 2001 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.
-
-/*
- * Copyright (c) 1997-1999
- * Silicon Graphics Computer Systems, Inc.
- *
- * Permission to use, copy, modify, distribute and sell this software
- * and its documentation for any purpose is hereby granted without fee,
- * provided that the above copyright notice appear in all copies and
- * that both that copyright notice and this permission notice appear
- * in supporting documentation. Silicon Graphics makes no
- * representations about the suitability of this software for any
- * purpose. It is provided "as is" without express or implied warranty.
- */
-
-/** @file stl_threads.h
- * This is an internal header file, included by other library headers.
- * You should not attempt to use it directly.
- */
-
-#ifndef __SGI_STL_INTERNAL_THREADS_H
-#define __SGI_STL_INTERNAL_THREADS_H
-
-// The only supported threading model is GCC's own gthr.h abstraction layer.
-#include "bits/gthr.h"
-
-namespace std
-{
- // Class _Refcount_Base provides a type, _RC_t, a data member,
- // _M_ref_count, and member functions _M_incr and _M_decr, which perform
- // atomic preincrement/predecrement. The constructor initializes
- // _M_ref_count.
- struct _Refcount_Base
- {
- // The type _RC_t
- typedef size_t _RC_t;
-
- // The data member _M_ref_count
- volatile _RC_t _M_ref_count;
-
- // Constructor
- __gthread_mutex_t _M_ref_count_lock;
-
- _Refcount_Base(_RC_t __n) : _M_ref_count(__n)
- {
-#ifdef __GTHREAD_MUTEX_INIT
- __gthread_mutex_t __tmp = __GTHREAD_MUTEX_INIT;
- _M_ref_count_lock = __tmp;
-#elif defined(__GTHREAD_MUTEX_INIT_FUNCTION)
- __GTHREAD_MUTEX_INIT_FUNCTION (&_M_ref_count_lock);
-#else
-#error __GTHREAD_MUTEX_INIT or __GTHREAD_MUTEX_INIT_FUNCTION should be defined by gthr.h abstraction layer, report problem to libstdc++@gcc.gnu.org.
-#endif
- }
-
- void
- _M_incr()
- {
- __gthread_mutex_lock(&_M_ref_count_lock);
- ++_M_ref_count;
- __gthread_mutex_unlock(&_M_ref_count_lock);
- }
-
- _RC_t
- _M_decr()
- {
- __gthread_mutex_lock(&_M_ref_count_lock);
- volatile _RC_t __tmp = --_M_ref_count;
- __gthread_mutex_unlock(&_M_ref_count_lock);
- return __tmp;
- }
- };
-
- // Atomic swap on unsigned long
- // This is guaranteed to behave as though it were atomic only if all
- // possibly concurrent updates use _Atomic_swap.
- // In some cases the operation is emulated with a lock.
-#if defined (__GTHREAD_MUTEX_INIT)
- // This could be optimized to use the atomicity.h abstraction layer.
- // vyzo: simple _Atomic_swap implementation following the guidelines above
- // We use a template here only to get a unique initialized instance.
- template<int __dummy>
- struct _Swap_lock_struct
- { static __gthread_mutex_t _S_swap_lock; };
-
- template<int __dummy>
- __gthread_mutex_t
- _Swap_lock_struct<__dummy>::_S_swap_lock = __GTHREAD_MUTEX_INIT;
-
- // This should be portable, but performance is expected to be quite
- // awful. This really needs platform specific code.
- inline unsigned long
- _Atomic_swap(unsigned long * __p, unsigned long __q)
- {
- __gthread_mutex_lock(&_Swap_lock_struct<0>::_S_swap_lock);
- unsigned long __result = *__p;
- *__p = __q;
- __gthread_mutex_unlock(&_Swap_lock_struct<0>::_S_swap_lock);
- return __result;
- }
-#endif
-
- // Locking class. Note that this class *does not have a
- // constructor*. It must be initialized either statically, with
- // __STL_MUTEX_INITIALIZER, or dynamically, by explicitly calling
- // the _M_initialize member function. (This is similar to the ways
- // that a pthreads mutex can be initialized.) There are explicit
- // member functions for acquiring and releasing the lock.
-
- // There is no constructor because static initialization is
- // essential for some uses, and only a class aggregate (see section
- // 8.5.1 of the C++ standard) can be initialized that way. That
- // means we must have no constructors, no base classes, no virtual
- // functions, and no private or protected members.
-
-#if !defined(__GTHREAD_MUTEX_INIT) && defined(__GTHREAD_MUTEX_INIT_FUNCTION)
- extern __gthread_mutex_t _GLIBCPP_mutex;
- extern __gthread_mutex_t *_GLIBCPP_mutex_address;
- extern __gthread_once_t _GLIBCPP_once;
- extern void _GLIBCPP_mutex_init (void);
- extern void _GLIBCPP_mutex_address_init (void);
-#endif
-
- struct _STL_mutex_lock
- {
- // The class must be statically initialized with __STL_MUTEX_INITIALIZER.
-#if !defined(__GTHREAD_MUTEX_INIT) && defined(__GTHREAD_MUTEX_INIT_FUNCTION)
- volatile int _M_init_flag;
- __gthread_once_t _M_once;
-#endif
- __gthread_mutex_t _M_lock;
-
- void
- _M_initialize()
- {
-#ifdef __GTHREAD_MUTEX_INIT
- // There should be no code in this path given the usage rules above.
-#elif defined(__GTHREAD_MUTEX_INIT_FUNCTION)
- if (_M_init_flag) return;
- if (__gthread_once (&_GLIBCPP_once, _GLIBCPP_mutex_init) != 0
- && __gthread_active_p ())
- abort ();
- __gthread_mutex_lock (&_GLIBCPP_mutex);
- if (!_M_init_flag)
- {
- // Even though we have a global lock, we use __gthread_once to be
- // absolutely certain the _M_lock mutex is only initialized once on
- // multiprocessor systems.
- _GLIBCPP_mutex_address = &_M_lock;
- if (__gthread_once (&_M_once, _GLIBCPP_mutex_address_init) != 0
- && __gthread_active_p ())
- abort ();
- _M_init_flag = 1;
- }
- __gthread_mutex_unlock (&_GLIBCPP_mutex);
-#endif
- }
-
- void
- _M_acquire_lock()
- {
-#if !defined(__GTHREAD_MUTEX_INIT) && defined(__GTHREAD_MUTEX_INIT_FUNCTION)
- if (!_M_init_flag) _M_initialize();
-#endif
- __gthread_mutex_lock(&_M_lock);
- }
-
- void
- _M_release_lock()
- {
-#if !defined(__GTHREAD_MUTEX_INIT) && defined(__GTHREAD_MUTEX_INIT_FUNCTION)
- if (!_M_init_flag) _M_initialize();
-#endif
- __gthread_mutex_unlock(&_M_lock);
- }
- };
-
-#ifdef __GTHREAD_MUTEX_INIT
-#define __STL_MUTEX_INITIALIZER = { __GTHREAD_MUTEX_INIT }
-#elif defined(__GTHREAD_MUTEX_INIT_FUNCTION)
-#ifdef __GTHREAD_MUTEX_INIT_DEFAULT
-#define __STL_MUTEX_INITIALIZER \
- = { 0, __GTHREAD_ONCE_INIT, __GTHREAD_MUTEX_INIT_DEFAULT }
-#else
-#define __STL_MUTEX_INITIALIZER = { 0, __GTHREAD_ONCE_INIT }
-#endif
-#endif
-
- // A locking class that uses _STL_mutex_lock. The constructor takes a
- // reference to an _STL_mutex_lock, and acquires a lock. The
- // destructor releases the lock. It's not clear that this is exactly
- // the right functionality. It will probably change in the future.
- struct _STL_auto_lock
- {
- _STL_mutex_lock& _M_lock;
-
- _STL_auto_lock(_STL_mutex_lock& __lock) : _M_lock(__lock)
- { _M_lock._M_acquire_lock(); }
-
- ~_STL_auto_lock() { _M_lock._M_release_lock(); }
-
- private:
- void operator=(const _STL_auto_lock&);
- _STL_auto_lock(const _STL_auto_lock&);
- };
-
-} // namespace std
-
-#endif
projects / msp430-gcc.git / blobdiff