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/******************************************************************************
 *
 *  Copyright (C) 2012 Broadcom Corporation
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at:
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 ******************************************************************************/

/******************************************************************************
 *
 *  Encapsulate a condition variable for thread synchronization.
 *
 ******************************************************************************/

#pragma once
#include <pthread.h>
#include "Mutex.h"


class CondVar
{
public:
    /*******************************************************************************
    **
    ** Function:        CondVar
    **
    ** Description:     Initialize member variables.
    **
    ** Returns:         None.
    **
    *******************************************************************************/
    CondVar ();


    /*******************************************************************************
    **
    ** Function:        ~CondVar
    **
    ** Description:     Cleanup all resources.
    **
    ** Returns:         None.
    **
    *******************************************************************************/
    ~CondVar ();


    /*******************************************************************************
    **
    ** Function:        wait
    **
    ** Description:     Block the caller and wait for a condition.
    **
    ** Returns:         None.
    **
    *******************************************************************************/
    void wait (Mutex& mutex);


    /*******************************************************************************
    **
    ** Function:        wait
    **
    ** Description:     Block the caller and wait for a condition.
    **                  millisec: Timeout in milliseconds.
    **
    ** Returns:         True if wait is successful; false if timeout occurs.
    **
    *******************************************************************************/
    bool wait (Mutex& mutex, long millisec);


    /*******************************************************************************
    **
    ** Function:        notifyOne
    **
    ** Description:     Unblock the waiting thread.
    **
    ** Returns:         None.
    **
    *******************************************************************************/
    void notifyOne ();

private:
    pthread_cond_t mCondition;
};