pushlist.h

mysee网络直播源代码Mysee Lite是Mysee独立研发的网络视频流媒体播放系统。在应有了P2P技术和一系列先进流媒体技术之后

/*
 *  Openmysee
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */
#pragma once

class ReqBlock {
public:
	UINT	blockID;	// 编号
	DWORD	reqTime;	// 开始请求的时间

	bool operator == (const UINT& blockID) const {
		return (this->blockID == blockID);
	};
};

class PushList {
public:
	// 构造函数
	explicit PushList() : m_array(0), m_totalsize(0), m_validsize(0) {
	};
	// 拷贝构造函数
	explicit PushList(const PushList& another) : m_array(NULL), m_totalsize(another.m_totalsize), m_validsize(another.m_validsize) {
		if(m_totalsize) {
			m_array = new ReqBlock[m_totalsize];
			memcpy(m_array, another.m_array, m_validsize*sizeof(ReqBlock));
		}
	};

	virtual ~PushList(void)	{
		m_totalsize = 0;
		m_validsize = 0;
		delete [] m_array;
		m_array = NULL;
	}

	// 添加一个块
	bool AddBlock(UINT blockID, DWORD reqTime=0) {
		assert(blockID != UINT_MAX);

		// 查找是否存在重复的块，如果存在就返回false
		if(find(m_array, m_array+m_validsize, blockID)  != m_array+m_validsize)
			return false;

		ReqBlock* temp = m_array;
		if(m_validsize == m_totalsize) {
			// 如果没有无效区间可以使用，那么需要增加数组大小
			// 分配一个空间更大的数组，并把区间i之前的数据复制过去
			m_array = new ReqBlock[m_validsize+1];
			memcpy(m_array, temp, m_validsize*sizeof(ReqBlock));
		}

		// 将此块添加到数组末尾
		m_array[m_validsize].blockID = blockID;
		m_array[m_validsize].reqTime = reqTime;

		// 此时m_totalsize和m_validsize尚未增加计数，所以可以用来判断是否增加过区间大小
		if(m_validsize == m_totalsize) {
			// 删除旧的数组，并增加数组大小的计数
			delete [] temp;
			++m_totalsize;
		}

		++m_validsize;
		return true;
	};

	// 删除一个块
	bool DelBlock(UINT blockID, DWORD * const reqTime=NULL) {
		assert(blockID != UINT_MAX);
		// 查找是否存在此块，如果不存在就返回false
		ReqBlock* index = find(m_array, m_array+m_validsize, blockID);
		if(index == m_array+m_validsize)
			return false;

		// 获取此块开始请求的时间
		if(reqTime)
			*reqTime = index->reqTime;

		// 删除此块，并将后面的块向前移动
		memcpy(index, index+1, (m_array+m_validsize-index-1)*sizeof(ReqBlock));
		--m_validsize;
		return true;
	};

	// 查找一个block是否存在
	bool FindBlock(const UINT blockID) const {
		// 查找是否存在此块，如果不存在就返回false
		return (find(m_array, m_array+m_validsize, blockID) != m_array+m_validsize);
	};

	// 复制block数组到传入的指针，传入需要的个数，返回实际复制的个数
	void CopyPushList(UINT* targetArray, UINT8& size) const {
		if(!targetArray || size == 0)
			return;
		size = min(size, m_validsize);
		for(UINT8 i = 0; i < size; ++i) {
			targetArray[i] = m_array[i].blockID;
		}
		//memcpy(targetArray, m_array, size*sizeof(UINT));
	};

	// 清空列表
	void Clear() {
		m_validsize = 0;
	};

	// 测试代码，打印出当前数组中的项
	void Print() const {
		printf("\nTOTAL: %d, VALID: %d.\n", m_totalsize, m_validsize);
		for(UINT8 i = 0; i < m_validsize; ++i) {
			printf("BLOCKID: %d, REQTIME: %d.\n", m_array[i].blockID, m_array[i].reqTime);
		}
	};

	// 取得有效元素的个数
	UINT8 GetValidSize() {
		return m_validsize;
	};

	// 取得当前容量
	UINT8 GetTotalSize() {
		return m_totalsize;
	};

	// 取出第一个元素
	void GetFirstBlock(UINT& blockID) {
		if(!m_validsize)
			blockID = UINT_MAX;
		else {
			blockID = m_array[0].blockID;
			memcpy(m_array, m_array+1, (m_validsize-1)*sizeof(ReqBlock));
			--m_validsize;
		}
	};

private:
	// 正在请求的块，保证无重复
	ReqBlock* m_array;
	// 数组的使用大小
	UINT8 m_totalsize;
	// 从数组头部开始有效元素的个数
	UINT8 m_validsize;
};