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#ifndef ITO_MUTEX_H
#define ITO_MUTEX_H

#include <pthread.h>

namespace Bu
{
	/**
	 * Simple mutex wrapper.  Currently this doesn't do anything extra for you
	 * except keep all of the functionality together in an OO sorta' way and keep
	 * you from having to worry about cleaning up your mutexes properly, or initing
	 * them.
	 *@author Mike Buland
	 */
	class ItoMutex
	{
	public:
		/**
		 * Create an unlocked mutex.
		 */
		ItoMutex();
		
		/**
		 * Destroy a mutex.  This can only be done when a mutex is unlocked.
		 * Failure to unlock before destroying a mutex object could cause it to
		 * wait for the mutex to unlock, the odds of which are usually farily low
		 * at deconstruction time.
		 */
		~ItoMutex();

		/**
		 * Lock the mutex.  This causes all future calls to lock on this instance
		 * of mutex to block until the first thread that called mutex unlocks it.
		 * At that point the next thread that called lock will get a chance to go
		 * to work.  Because of the nature of a mutex lock it is a very bad idea to
		 * do any kind of serious or rather time consuming computation within a
		 * locked section.  This can cause thread-deadlock and your program may
		 * hang.
		 */
		int lock();

		/**
		 * Unlock the mutex.  This allows the next thread that asked for a lock to
		 * lock the mutex and continue with execution.
		 */
		int unlock();

		/**
		 * Try to lock the mutex.  This is the option to go with if you cannot avoid
		 * putting lengthy operations within a locked section.  trylock will attempt
		 * to lock the mutex, if the mutex is already locked this function returns
		 * immediately with an error code.
		 */
		int trylock();

	protected:
		pthread_mutex_t mutex;	/**< The internal mutex reference. */
	};
}

#endif