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  #ifndef AVBTS_OSSIGNAL_HPP
  #define AVBTS_OSSIGNAL_HPP
  
  /**@file*/
  
  /**
   * @brief Provides a generic interface for OS's locking condition
   */
  class OSCondition {
  private:
  	int wait_count;
  public:
  	/**
  	 * @brief Waits until a condition is met
  	 * @return TRUE after waiting
  	 */
  	virtual bool wait() = 0;
  
  	/**
  	 * @brief Waits for lock
  	 * @return TRUE after waiting
  	 */
  	virtual bool wait_prelock() = 0;
  
  	/**
  	 * @brief Sends a signal to unblock other threads
  	 * @return TRUE
  	 */
  	virtual bool signal() = 0;
  
  	/**
  	 * @brief Deletes previously declared flags
  	 */
  	virtual ~OSCondition() = 0;
  protected:
  	/**
  	 * @brief Default constructor. Initializes internal variables
  	 */
  	OSCondition() {
  		wait_count = 0;
  	};
  
  	/**
  	 * @brief  Counts up waiting condition
  	 * @return void
  	 */
  	void up() {
  		++wait_count;
  	}
  
  	/**
  	 * @brief  Conds down waiting condition
  	 * @return void
  	 */
  	void down() {
  		--wait_count;
  	}
  
  	/**
  	 * @brief  Checks if OS is waiting
  	 * @return TRUE if up counter is greater than zero. FALSE otherwise.
  	 */
  	bool waiting() {
  		return wait_count > 0;
  	}
  };
  
  inline OSCondition::~OSCondition() { }
  
  /**
   * @brief Provides factory design patter for OS Condition class
   */
  class OSConditionFactory {
  public:
  	/**
  	 * @brief  Creates OSCondition class
  	 * @return Pointer to OSCondition object
  	 */
  	virtual OSCondition *createCondition() const = 0;
  
  	/**
  	 * @brief Destroys OSCondition objects
  	 */
  	virtual ~OSConditionFactory() = 0;
  };
  
  inline OSConditionFactory::~OSConditionFactory() {}
  
  
  #endif
  