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Diffstat (limited to 'dep/include/zthread/Mutex.h')
-rw-r--r-- | dep/include/zthread/Mutex.h | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/dep/include/zthread/Mutex.h b/dep/include/zthread/Mutex.h new file mode 100644 index 00000000000..1b521b1598d --- /dev/null +++ b/dep/include/zthread/Mutex.h @@ -0,0 +1,135 @@ +/* + * Copyright (c) 2005, Eric Crahen + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is furnished + * to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all + * copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, + * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + * + */ + +#ifndef __ZTMUTEX_H__ +#define __ZTMUTEX_H__ + +#include "zthread/Lockable.h" +#include "zthread/NonCopyable.h" + +namespace ZThread { + + class FifoMutexImpl; + + /** + * @class Mutex + * @author Eric Crahen <http://www.code-foo.com> + * @date <2003-07-16T19:35:28-0400> + * @version 2.2.1 + * + * A Mutex is used to provide serialized (one thread at a time) access to some portion + * of code. This is accomplished by attempting to acquire the Mutex before entering that + * piece of code, and by releasing the Mutex when leaving that region. It is a non-reentrant, + * MUTual EXclusion Lockable object. + * + * @see Guard + * + * <b>Scheduling</b> + * + * Threads competing to acquire() a Mutex are granted access in FIFO order. + * + * <b>Error Checking</b> + * + * A Mutex will throw a Deadlock_Exception if an attempt to acquire a Mutex more + * than once is made from the context of the same thread. + * + * A Mutex will throw an InvalidOp_Exception if an attempt to release a Mutex is + * made from the context of a thread that does not currently own that Mutex. + */ + class ZTHREAD_API Mutex : public Lockable, private NonCopyable { + + FifoMutexImpl* _impl; + + public: + + //! Create a new Mutex. + Mutex(); + + //! Destroy this Mutex. + virtual ~Mutex(); + + /** + * Acquire a Mutex, possibly blocking until either the current owner of the + * Mutex releases it or until an exception is thrown. + * + * Only one thread may acquire() the Mutex at any given time. + * + * @exception Interrupted_Exception thrown when the calling thread is interrupted. + * A thread may be interrupted at any time, prematurely ending any wait. + * @exception Deadlock_Exception thrown when the same thread attempts to acquire + * a Mutex more than once, without having first release()ed it. + * + * @pre the calling thread must not have already acquired Mutex + * + * @post the calling thread successfully acquired Mutex only if no exception + * was thrown. + * + * @see Lockable::acquire() + */ + virtual void acquire(); + + /** + * Acquire a Mutex, possibly blocking until the current owner of the + * Mutex releases it, until an exception is thrown or until the given amount + * of time expires. + * + * Only one thread may acquire the Mutex at any given time. + * + * @param timeout maximum amount of time (milliseconds) this method could block + * @return + * - <em>true</em> if the lock was acquired + * - <em>false</em> if the lock was acquired + * + * @exception Interrupted_Exception thrown when the calling thread is interrupted. + * A thread may be interrupted at any time, prematurely ending any wait. + * @exception Deadlock_Exception thrown when the same thread attempts to acquire + * a Mutex more than once, without having first released it. + * + * @pre the calling thread must not have already acquired Mutex + * + * @post the calling thread successfully acquired Mutex only if no exception + * was thrown. + * + * @see Lockable::tryAcquire(unsigned long timeout) + */ + virtual bool tryAcquire(unsigned long timeout); + + /** + * Release a Mutex allowing another thread to acquire it. + * + * @exception InvalidOp_Exception - thrown if there is an attempt to release is + * a Mutex that was not owner by the calling thread. + * + * @pre the calling thread must have first acquired the Mutex. + * @post the calling thread successfully released Mutex only if no exception + * was thrown. + * + * @see Lockable::release() + */ + virtual void release(); + + }; + + +} // namespace ZThread + +#endif // __ZTMUTEX_H__ |