queue.cpp

CE下基于PXA255的蓝牙驱动

//
// Copyright (c) Microsoft Corporation.  All rights reserved.
//
//
// Use of this source code is subject to the terms of the Microsoft end-user
// license agreement (EULA) under which you licensed this SOFTWARE PRODUCT.
// If you did not accept the terms of the EULA, you are not authorized to use
// this source code. For a copy of the EULA, please see the LICENSE.RTF on your
// install media.
//
#include "queue.h"

CSimpleQueue::CSimpleQueue()
{
    memset(m_dwElements, 0, sizeof(m_dwElements));
    m_dwStartIdx = 0;
    m_dwLen = 0;
}

CSimpleQueue::~CSimpleQueue()
{
}

BOOL CSimpleQueue::Enqueue(DWORD dwElement)
{
    if (m_dwLen >= MAX_QUEUE_ELEMENTS)
        return FALSE;
    DWORD idx = (m_dwStartIdx + m_dwLen) % MAX_QUEUE_ELEMENTS;
    m_dwElements[idx] = dwElement;
    m_dwLen++;
    return TRUE;
}

BOOL CSimpleQueue::Dequeue(PDWORD pdwElement)
{
    if (m_dwLen == 0)
        return FALSE;
    *pdwElement = m_dwElements[m_dwStartIdx];
    m_dwStartIdx = (m_dwStartIdx + 1) % MAX_QUEUE_ELEMENTS;
    m_dwLen--;
    return TRUE;
}

BOOL CSimpleQueue::PeekDequeue(PDWORD pdwElement)
{
    if (m_dwLen == 0)
        return FALSE;
    *pdwElement = m_dwElements[m_dwStartIdx];
    return TRUE;
}

DWORD CSimpleQueue::GetNumElements()
{
    return m_dwLen;
}