无锁的环形队列

#ifndef _RingQueue_H_
#define _RingQueue_H_
#include <memory.h>
template<class T, unsigned int MAX_LEN = 1024>
class RingQueue
{
public://-----------------------------------------------------// 构造//-----------------------------------------------------
    RingQueue(){m_nHead = 0;m_nTail = 0;}//-----------------------------------------------------// 析构//-----------------------------------------------------~RingQueue(){}//-----------------------------------------------------// 重置，清空队列//-----------------------------------------------------void    Reset(){m_nHead = 0;m_nTail = 0;}//-----------------------------------------------------// 取得最多读取个数//-----------------------------------------------------unsigned int        GetMaxReadSize(){int size = (m_nTail - m_nHead + MAX_LEN) % MAX_LEN;return size;}//-----------------------------------------------------// 取得最多写入个数//-----------------------------------------------------unsigned int        GetMaxWriteSize(){int size = (m_nHead - m_nTail + MAX_LEN - 1) % MAX_LEN; return size;}//-----------------------------------------------------// 添加数据//-----------------------------------------------------bool    PushData(const T* pData, unsigned int nLength = 1){if (pData == nullptr || nLength > GetMaxWriteSize()){return false;}if (m_nTail + nLength <= MAX_LEN){memcpy(m_Buffer + m_nTail, pData, nLength * sizeof(T));m_nTail = (m_nTail + nLength) % MAX_LEN;}else{unsigned int size1 = MAX_LEN - m_nTail;unsigned int size2 = nLength - size1;memcpy(m_Buffer + m_nTail, pData, size1 * sizeof(T));memcpy(m_Buffer, pData+size1, size2 * sizeof(T));m_nTail = size2;}return true;}//-----------------------------------------------------// 取出并删除数据//-----------------------------------------------------bool    PopData(T* pData, unsigned int nLength = 1){if (pData == nullptr || nLength > GetMaxReadSize() || nLength <= 0){return false;}if (m_nHead + nLength <= MAX_LEN){memcpy(pData, m_Buffer + m_nHead, nLength * sizeof(T));m_nHead    = (m_nHead + nLength) % MAX_LEN;}else{unsigned int size1 = MAX_LEN - m_nHead;unsigned int size2 = nLength - size1;memcpy(pData, m_Buffer + m_nHead, size1 * sizeof(T));memcpy(pData + size1, m_Buffer, size2 * sizeof(T));m_nHead = size2;}return true;}//-----------------------------------------------------// 查看数据 不删除//-----------------------------------------------------bool    PeekData(T* pData, unsigned int nLen){if (nLen > GetMaxReadSize() || nLen <= 0){return false;}if (m_nHead + nLen <= MAX_LEN){memcpy(pData, m_Buffer + m_nHead, nLen * sizeof(T));}else{unsigned int size1 = MAX_LEN - m_nHead;unsigned int size2 = nLen - size1;memcpy(pData, m_Buffer + m_nHead, size1 * sizeof(T));memcpy(pData + size1, m_Buffer, size2 * sizeof(T));}return true;}//-----------------------------------------------------// 删除数据//-----------------------------------------------------bool    DeleteData(unsigned int nLen){if (nLen > GetMaxReadSize() || nLen <= 0){return false;}if (m_nHead + nLen <= MAX_LEN ){m_nHead    = (m_nHead + nLen) % MAX_LEN;}else{m_nHead = nLen - (MAX_LEN - m_nHead);}return true;}public:T    m_Buffer[MAX_LEN];    // 数据区
private:unsigned int    m_nHead;                        // 队头unsigned int    m_nTail;                        // 队尾

};#endif