70 lines
1.7 KiB
C++
70 lines
1.7 KiB
C++
// Copyright (C) 2000 Stephen Cleary
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//
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// Distributed under the Boost Software License, Version 1.0. (See
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// accompanying file LICENSE_1_0.txt or copy at
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// http://www.boost.org/LICENSE_1_0.txt)
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//
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// See http://www.boost.org for updates, documentation, and revision history.
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#ifndef BOOST_POOL_GUARD_HPP
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#define BOOST_POOL_GUARD_HPP
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/*!
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\file
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\brief Extremely Light-Weight guard class.
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\details Auto-lock/unlock-er
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detail/guard.hpp provides a type guard<Mutex>
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that allows scoped access to the Mutex's locking and unlocking operations.
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It is used to ensure that a Mutex is unlocked, even if an exception is thrown.
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*/
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namespace boost {
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namespace details {
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namespace pool {
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template <typename Mutex> //!< \tparam Mutex (platform-specific) mutex class.
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class guard
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{ //! Locks the mutex, binding guard<Mutex> to Mutex.
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/*! Example:
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Given a (platform-specific) mutex class, we can wrap code as follows:
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extern mutex global_lock;
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static void f()
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{
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boost::details::pool::guard<mutex> g(global_lock);
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// g's constructor locks "global_lock"
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... // do anything:
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// throw exceptions
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// return
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// or just fall through
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} // g's destructor unlocks "global_lock"
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*/
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private:
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Mutex & mtx;
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guard(const guard &); //!< Guards the mutex, ensuring unlocked on destruction, even if exception is thrown.
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void operator=(const guard &);
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public:
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explicit guard(Mutex & nmtx)
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:mtx(nmtx)
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{ //! Locks the mutex of the guard class.
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mtx.lock();
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}
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~guard()
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{ //! destructor unlocks the mutex of the guard class.
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mtx.unlock();
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}
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}; // class guard
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} // namespace pool
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} // namespace details
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} // namespace boost
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#endif
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