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108 lines
2.3 KiB
C++
108 lines
2.3 KiB
C++
//
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// NamedMutex.h
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//
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// Library: Foundation
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// Package: Processes
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// Module: NamedMutex
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//
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// Definition of the NamedMutex class.
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//
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// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
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// and Contributors.
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//
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// SPDX-License-Identifier: BSL-1.0
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//
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#ifndef Foundation_NamedMutex_INCLUDED
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#define Foundation_NamedMutex_INCLUDED
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#include "Poco/Foundation.h"
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#include "Poco/ScopedLock.h"
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#if POCO_OS == POCO_OS_ANDROID
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# include "Poco/NamedMutex_Android.h"
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#elif defined(POCO_OS_FAMILY_UNIX)
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# include "Poco/NamedMutex_UNIX.h"
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#endif
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namespace Poco
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{
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class Foundation_API NamedMutex : private NamedMutexImpl
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/// A NamedMutex (mutual exclusion) is a global synchronization
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/// mechanism used to control access to a shared resource
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/// in a concurrent (multi process) scenario.
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/// Using the ScopedLock class is the preferred way to automatically
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/// lock and unlock a mutex.
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///
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/// Unlike a Mutex or a FastMutex, which itself is the unit of synchronization,
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/// a NamedMutex refers to a named operating system resource being the
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/// unit of synchronization.
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/// In other words, there can be multiple instances of NamedMutex referring
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/// to the same actual synchronization object.
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///
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///
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/// There should not be more than one instance of NamedMutex for
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/// a given name in a process. Otherwise, the instances may
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/// interfere with each other.
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{
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public:
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typedef Poco::ScopedLock<NamedMutex> ScopedLock;
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NamedMutex(const std::string & name);
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/// creates the Mutex.
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~NamedMutex();
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/// destroys the Mutex.
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void lock();
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/// Locks the mutex. Blocks if the mutex
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/// is held by another process or thread.
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bool tryLock();
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/// Tries to lock the mutex. Returns false immediately
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/// if the mutex is already held by another process or thread.
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/// Returns true if the mutex was successfully locked.
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void unlock();
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/// Unlocks the mutex so that it can be acquired by
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/// other threads.
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private:
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NamedMutex();
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NamedMutex(const NamedMutex &);
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NamedMutex & operator=(const NamedMutex &);
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};
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//
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// inlines
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//
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inline void NamedMutex::lock()
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{
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lockImpl();
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}
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inline bool NamedMutex::tryLock()
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{
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return tryLockImpl();
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}
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inline void NamedMutex::unlock()
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{
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unlockImpl();
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}
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} // namespace Poco
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#endif // Foundation_NamedMutex_INCLUDED
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