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/*****************************************************************************/<2011_0725_0141>
   
    
     
      无缓冲区写文件, 写文件完成后, 设置正确的FileTotalSize用无缓冲区写文件的目的: 某些程序会拦截, 替换fopen操作的文件内容, 应用层无法得到真实的文件数据, 这时需要用无缓冲区读写的方式来裸读.知识点: * CreateFile时带上标记FILE_FLAG_NO_BUFFERING* WriteFile时，需要写入扇区对齐或扇区倍数的块, 如果不够块大小, 在写入区先放着  在往写入区中写的时候, 不管是否写入了磁盘, 都需要自己维护写入的FileTotalSize  用来在文件完全写入后，设置正确的FileSize.* 用GetDiskFreeSpace来得到目标文件所在驱动器的扇区大小.* 为了提高写入速度, 应给出一个较大的缓冲区容量并按照扇区大小进行规约* 写入完成后, 关闭文件. 再打开文件, SetFilePointer, SetEndOfFile 设置文件的正确大小/*****************************************************************************/
     
    
   

// FileOPT.cpp : Defines the entry point for the console application.//#include "stdafx.h"#include 
   
    #include "helper/helper_file.h"USE_NAMESPACE_LSLS_RC BuildTestSrc(TCHAR * pcPathNameSrc, HANDLE & hFileSrc, BYTE* pucBufRd, size_t nSizeBufRd);int _tmain(int argc, _TCHAR* argv[]){	LS_RC lsRc = LS_RC_OK;	BYTE ucBufRd[_MAX_PATH];//从其他地方读来的数据, 每次得到之后, 循环写入文件	PBYTE pucWriteNoCache = NULL;//以扇区倍数为单位写入块	DWORD dwRdBack = 0;//从其他地方读来的数据在ucBufRd中的字节数量	TAG_WIRTE_BUF_NO_CACHE_INFO sWriteBufNoCache;//无缓冲写入的结构, 用于带多个参数, 简化函数入参数量	DWORD dwWrBack = 0;//从其他地方读来的数据在ucBufRd中的字节数量	DWORD dwWirteBufLen = 0;//无缓冲方式要按照扇区写入, 一次性写入此扇区到文件	HANDLE hFileSrc = INVALID_HANDLE_VALUE;//从hFileSrc读内容	HANDLE hFileDst = INVALID_HANDLE_VALUE;//将读到的内容写到这里hFileDst	TCHAR * pcPathNameDst = _T("c:\\tmp\\dir1\\dir2\\fileOptTest.txt");//要写入内容的文件	/** 假设写入的数据来源于磁盘上已经存在的文件 c:\\testForRd.txt, 这个文件的大小为 2345 */	TCHAR * pcPathNameSrc = _T("c:\\testForRd.txt");	lsRc = LsCreateFileEngrossNoCache(pcPathNameDst, hFileDst);	if(LS_RC_OK != lsRc)	{		goto __tmain_END;	}	//得到无缓冲方式写时，以扇区倍数为大小的块长度	lsRc = LsGetWriteBufferLenForWirteFileNoCache(pcPathNameDst, sizeof(ucBufRd), dwWirteBufLen);	if(LS_RC_OK != lsRc)	{		goto __tmain_END;	}	/** 	* 只开1个,2个扇区, 明显慢了, 120M的文件写完，超过了1分钟	* 按扇区倍数规约到1M, 试验表明, 10秒钟左右, 120M就写完了~	* 117 MB (123,456,789 字节)	*/	lsRc = LsGetSectorMultiple(1024 * 1024, dwWirteBufLen, dwWirteBufLen);	if(LS_RC_OK != lsRc)	{		goto __tmain_END;	}	pucWriteNoCache = new BYTE[dwWirteBufLen];//按扇区倍数为单位的写入块	if(!pucWriteNoCache)	{		lsRc = MakeLsErrSn(LS_RC_MEMORY_ALLOC);		goto __tmain_END;	}	//建立一个数据来源, 用于读取此数据来源写到pcPathNameDst	lsRc = BuildTestSrc(pcPathNameSrc, hFileSrc, &ucBufRd[0], sizeof(ucBufRd));	lsRc = LsOpenFileForRead(pcPathNameSrc, hFileSrc);	if(LS_RC_OK != lsRc)	{		goto __tmain_END;	}	//read src write to dst, write by no cache!	ZeroMemory(&sWriteBufNoCache, sizeof(TAG_WIRTE_BUF_NO_CACHE_INFO));	sWriteBufNoCache.dwLenBufNoCache = dwWirteBufLen;	sWriteBufNoCache.dwPosToWrite = 0;//由LsWriteFileNoCache决定	sWriteBufNoCache.hFileToWrite = hFileDst;	sWriteBufNoCache.llTotalWriteIn = 0;	sWriteBufNoCache.pBufNoCache = pucWriteNoCache;	sWriteBufNoCache.pBufToWrite = ucBufRd;	while(ReadFile(hFileSrc, ucBufRd, sizeof(ucBufRd), &dwRdBack, NULL))	{		if(dwRdBack <= 0)		{			break;//已经读完了		}		sWriteBufNoCache.dwLenToWrite = dwRdBack;//由ReadFile来决定		sWriteBufNoCache.dwLenWrBack = 0;//由LsWriteFileNoCache决定		lsRc = LsWriteFileNoCache(sWriteBufNoCache);		if((LS_RC_OK != lsRc) || (dwRdBack != sWriteBufNoCache.dwLenWrBack))		{			lsRc = MakeLsErrSn(LS_RC_ERR_FILE_WRITE);			goto __tmain_END;		}	}	lsRc = LsWriteFileNoCache_FulshData(sWriteBufNoCache);	if(LS_RC_OK != lsRc)	{		lsRc = MakeLsErrSn(LS_RC_ERR_FILE_WRITE);		goto __tmain_END;	}	LsCloseHandle(hFileDst);	/** 在关闭文件后, 重新打开文件, 设置文件实际size */	lsRc = LsOpenFileForWrite(pcPathNameDst, hFileDst);	if(LS_RC_OK != lsRc)	{		lsRc = MakeLsErrSn(LS_RC_ERR_FILE_WRITE);		goto __tmain_END;	}	lsRc = LsSetFilePointer(sWriteBufNoCache);	if(LS_RC_OK != lsRc)	{		lsRc = MakeLsErrSn(LS_RC_ERR_FILE_WRITE);		goto __tmain_END;	}__tmain_END:	LsCloseHandle(hFileSrc);	LsCloseHandle(hFileDst);	LsDelete(pucWriteNoCache);	if(LS_RC_OK == lsRc)	{	}	else	{		_tprintf(_T("sir: some error was happen, please check the progam\n"));		getchar();	}	return 0;}LS_RC BuildTestSrc(TCHAR * pcPathNameSrc, HANDLE & hFileSrc, BYTE* pucBufRd, size_t nSizeBufRd){	LS_RC lsRc = LS_RC_OK;	DWORD dwSizeRdBack = 27;//每次写入pcPathNameSrc的测试内容长度, 随便一个非特殊，非对齐的长度	DWORD dwSizeWrBack = 0;//每次写入pcPathNameSrc dwSizeRdBack长度后, 返回的写入长度	size_t nTotalWrite = 0;//总共写入的字节数	size_t n = 0;	BOOL bStopWriteSrc = FALSE;	LONGLONG llSizeWirteToSrc = 123456789;//写入pcPathNameSrc的测试内容总长度, 123456789是100多M的大小	lsRc = LsCreateFile(pcPathNameSrc, hFileSrc);	if(LS_RC_OK != lsRc)	{		goto _BuildTestSrc_END;	}	for(n = 0; n < nSizeBufRd; n++)	{		*(pucBufRd + n) = (BYTE)(n % 0xff);	}	bStopWriteSrc = FALSE;//为最后一次写测试文件src准备的	while(llSizeWirteToSrc > 0)		{		if(llSizeWirteToSrc >= dwSizeRdBack)		{			llSizeWirteToSrc -= dwSizeRdBack;		}		else		{			dwSizeRdBack = (DWORD)llSizeWirteToSrc;			bStopWriteSrc = TRUE;		}		if(!WriteFile(hFileSrc, pucBufRd, dwSizeRdBack, &dwSizeWrBack, NULL))		{			//带缓冲方式写得时候, 不需要扇区对齐写, 写多少都是成功的, 且(dwSizeWrBack == dwSizeRdBack)			lsRc = MakeLsErrSn(LS_RC_ERR_FILE_WRITE);			goto _BuildTestSrc_END;		}		nTotalWrite += dwSizeWrBack;		if(dwSizeRdBack != dwSizeWrBack)		{			lsRc = MakeLsErrSn(LS_RC_ERR_FILE_WRITE);			goto _BuildTestSrc_END;		}			if(bStopWriteSrc)		{			break;		}	}_BuildTestSrc_END:	LsCloseHandle(hFileSrc);	return lsRc;}
   

/*** @file helper_file.h*/#ifndef _HELPER_FILE_H_#define _HELPER_FILE_H_#include "helper_common.h"#include "define/define_error.h"#include "define/define_struct_file.h"LS_NAMESPACE_BEGINLS_RC LsFindFile(CONST TCHAR * pcFileName);LS_RC LsCreateFile(TCHAR * pcFileName, HANDLE &hFile);				/**< 建立文件, 传出文件句柄 */LS_RC LsOpenFileForAppend(TCHAR * pcFileName, HANDLE &hFile);		/**< 打开现存文件去写, 传出文件句柄 */LS_RC LsOpenFileForRead(TCHAR * pcFileName, HANDLE &hFile);			/**< 打开现存文件去读, 传出文件句柄 */LS_RC LsOpenFileForWrite(TCHAR * pcFileName, HANDLE &hFile);		/**< 打开现存文件去写, 传出文件句柄 */LS_RC LsCloseHandle(HANDLE &hFile);			/**< 关闭文件件 */LS_RC LsDelete(PBYTE & pBuf);				/**< if (pBuf == TRUE), delete it */LS_RC LsWriteFile(HANDLE &hFile, LPCVOID pcBuf, DWORD dwSizeBuf);		/**< 写入文件内容 *//*WriteFile(hTempFile, buffer, dwBytesRead, &dwBytesWritten, NULL); *//** 独占方式文件操作 */LS_RC LsGetFullPathFromPathName(TCHAR * pcPathName, tstring & strPath);/**< 从全路径文件名中, 得到全路径 */LS_RC LsCreateFullPath(TCHAR * pcFullPath);/**< 建立给定的全路径目录 */LS_RC LsCreateFullPath(TCHAR * pcDriverName, std::vector
   
     & vecPath);/**< 按照驱动器名称和目录的vector, 建立全路径目录 */LS_RC LsSplitPathToVector(TCHAR * pcFullPath, std::vector
    
      & vecPath);LS_RC LsCreateFileEngrossNoCache(TCHAR * pcPathName, HANDLE & hFile); /**< 以独占无缓存方式建立文件 *//** * @fn LS_RC LsGetPathDiskInfo(TCHAR * pcPathName)* @brief 得到路径中的磁盘信息, 如果pcPathName是全路径文件名, 分解出路径作为查询条件*/LS_RC LsGetPathDiskInfo(TCHAR * pcPathName, TAG_PATH_INFO & pathInfo);/** 切分路径信息到pathInfo */LS_RC LsSplitPath(TCHAR * pcPathName, TAG_PATH_INFO & pathInfo);/** 从PcPathName中得到盘符, 查询磁盘空间, 填充DiskFreeSapce */LS_RC LsGetFreeDiskSapce(TCHAR * pcPathName, TAG_DISK_FREE_SPACE & DiskFreeSapce);/** 根据一次写入的最大字节数, 计算写缓冲区的大小* 独占无缓存方式写文件, 一次要写入磁盘扇区的倍数大小才能成功*/LS_RC LsGetWriteBufferLenForWirteFileNoCache(TCHAR * pcPathName, DWORD dwBytesOnceWriteMax, DWORD & dwWirteBufLen);/** 以扇区倍数为界限, 向给定容量规约 * 即取最靠近给定容量的扇区倍数的字节数*/LS_RC LsGetSectorMultiple(DWORD dwBytesUpperLimit, DWORD dwByteSectorBase, DWORD &dwSectorMultiple);/** 无缓冲方式的块写入 * 返回下一次写入的位置dwPosToWrite, 总共写入的字节数(用来写入完成后, 设置文件size)*/LS_RC LsWriteFileNoCache(TAG_WIRTE_BUF_NO_CACHE_INFO & sWriteBufNoCache);/** 最后一次的写, 然后调用关闭文件句柄 */LS_RC LsWriteFileNoCache_FulshData(TAG_WIRTE_BUF_NO_CACHE_INFO & sWriteBufNoCache);/** 设置文件指针 */LS_RC LsSetFilePointer(TAG_WIRTE_BUF_NO_CACHE_INFO & sWriteBufNoCache);/** 得Windows路径 */LS_RC LsGetWinOsPath(tstring & strPathName);LS_NAMESPACE_END#endif
    
   

/*** @file helper_flie.cpp*/#include 
   
    #include "helper_string.h"#include "define/define_error.h"#include "helper/helper_file.h"LS_NAMESPACE_BEGINLS_RC LsFindFile(CONST TCHAR * pcFileName){	tstring::size_type nPos = 0;	tstring::size_type nPosUnknown = -1;	LS_RC lsRc = LS_RC_OK;	WIN32_FIND_DATA FindFileData;	HANDLE hFind;	tstring strFileName;	strFileName = pcFileName;	nPos = strFileName.rfind(_T('\\'));	if((nPosUnknown != nPos) && (_T('\\') == strFileName.at(strFileName.length() - 1)))	{		/** 要查找的文件不能带 "\\" */		strFileName.replace(nPos, 1, _T("\0"));	}	hFind = FindFirstFile(strFileName.c_str(), &FindFileData);	if (hFind == INVALID_HANDLE_VALUE) 	{		lsRc = MakeLsErrSn(LS_RC_ERR_FILE_NOT_FIND);		goto _LsFindFile_END;	} 	else 	{		//_tprintf(_T("The first file found is %s\n"), FindFileData.cFileName);		FindClose(hFind);	}_LsFindFile_END:	return lsRc;}LS_RC LsCreateFile(TCHAR * pcFileName, HANDLE &hFile){/** 建立文件传出文件指针 */	LS_RC lsRc = LS_RC_OK;	hFile = CreateFile(pcFileName, 		GENERIC_WRITE,		FILE_SHARE_READ | FILE_SHARE_WRITE,		NULL,		CREATE_ALWAYS,		FILE_ATTRIBUTE_NORMAL,		NULL);	if(INVALID_HANDLE_VALUE == hFile)	{		lsRc = MakeLsErrSn(LS_RC_ERR_FILE_CREATE);		goto _LsCreateFile_END;	}_LsCreateFile_END:	return lsRc;}LS_RC LsOpenFileForAppend(TCHAR * pcFileName, HANDLE &hFile){/** 建立文件传出文件指针 */	LS_RC lsRc = LS_RC_OK;	LARGE_INTEGER FileSize;	hFile = CreateFile(pcFileName, 		GENERIC_READ | GENERIC_WRITE,		FILE_SHARE_READ | FILE_SHARE_WRITE,		NULL,		OPEN_EXISTING,		FILE_ATTRIBUTE_NORMAL,		NULL);	if(INVALID_HANDLE_VALUE == hFile)	{		lsRc = MakeLsErrSn(LS_RC_ERR_FILE_OPEN);		goto _LsOpenFileForAppend_END;	}	/** 如果是已经存在的日志文件, 移动到文件末尾, 形成附加日志的效果 */	if(GetFileSizeEx(hFile, &FileSize) && (FileSize.QuadPart > 0))	{		//_llseek((HFILE)hFile, 0, SEEK_END);//这种用法有个警告 :(		SetFilePointer(hFile, 0, NULL, FILE_END);	}_LsOpenFileForAppend_END:	return lsRc;}LS_RC LsOpenFileForRead(TCHAR * pcFileName, HANDLE &hFile){/** 建立文件传出文件指针 */	LS_RC lsRc = LS_RC_OK;	hFile = CreateFile(pcFileName, 		GENERIC_READ,		FILE_SHARE_READ,		NULL,		OPEN_EXISTING,		FILE_ATTRIBUTE_NORMAL,		NULL);	if(INVALID_HANDLE_VALUE == hFile)	{		lsRc = MakeLsErrSn(LS_RC_ERR_FILE_OPEN);		goto _LsOpenFileForAppend_END;	}_LsOpenFileForAppend_END:	return lsRc;}LS_RC LsOpenFileForWrite(TCHAR * pcFileName, HANDLE &hFile){/**< 打开现存文件去写, 传出文件句柄 */	LS_RC lsRc = LS_RC_OK;	hFile = CreateFile(pcFileName, 		GENERIC_READ | GENERIC_WRITE,		NULL,		0,		OPEN_EXISTING,		FILE_ATTRIBUTE_NORMAL,		NULL);	if(INVALID_HANDLE_VALUE == hFile)	{		lsRc = MakeLsErrSn(LS_RC_ERR_FILE_OPEN);		goto END;	}END:	return lsRc;}LS_RC LsWriteFile(HANDLE &hFile, LPCVOID pcBuf, DWORD dwSizeBuf){	LS_RC lsRc = LS_RC_OK;	BOOL bWriteOK = TRUE;	DWORD dwBytesWritten = 0;			/**< 总共写入的字节数 */	DWORD dwBytesWrittenOnce = 0;		/**< 一次写操作完成后, 已经写入的字节数 */	if(INVALID_HANDLE_VALUE == hFile)	{		lsRc = MakeLsErrSn(LS_RC_ERR_FILE_INVALID_HANDLE);		goto _LsWriteFile_END;	}	do 	{		bWriteOK = ::WriteFile(hFile, (PBYTE)pcBuf + dwBytesWritten, dwSizeBuf - dwBytesWritten, &dwBytesWrittenOnce, NULL);		if(!bWriteOK)		{			lsRc = MakeLsErrSn(LS_RC_ERR_FILE_WRITE);			goto _LsWriteFile_END; 		}		dwBytesWritten += dwBytesWrittenOnce;	}while((dwSizeBuf - dwBytesWritten) > 0);_LsWriteFile_END:	return lsRc;}LS_RC LsCloseHandle(HANDLE &hFile){	LS_RC lsRc = LS_RC_OK;	BOOL bCloseOK = TRUE;	if(INVALID_HANDLE_VALUE != hFile)	{		bCloseOK = CloseHandle(hFile);		if(bCloseOK)		{			hFile = INVALID_HANDLE_VALUE;		}		else		{			lsRc = MakeLsErrSn(LS_RC_ERR_FILE_CLOSE);			goto _LsCloseFile_END;		}	}_LsCloseFile_END:	return lsRc;}LS_RC LsDelete(PBYTE & pBuf){	if(pBuf)	{		delete pBuf;		pBuf = NULL;	}	return LS_RC_OK;}LS_RC LsCreateFileEngrossNoCache(TCHAR * pcPathName, HANDLE & hFile){	LS_RC lsRc = LS_RC_OK;	hFile = INVALID_HANDLE_VALUE;	lsRc = LsCreateFullPath(pcPathName);	if(LS_RC_OK != lsRc)	{		goto _LsCreateFileEngross_END;	}	hFile = CreateFile(		pcPathName,		GENERIC_READ | GENERIC_WRITE,		0,		NULL,		CREATE_ALWAYS,		FILE_ATTRIBUTE_NORMAL | FILE_ATTRIBUTE_NOT_CONTENT_INDEXED | FILE_FLAG_NO_BUFFERING,		NULL);	if(INVALID_HANDLE_VALUE == hFile)	{		lsRc = MakeLsErrSn(LS_RC_ERR_FILE_CREATE);	}_LsCreateFileEngross_END:	return lsRc;}LS_RC LsGetPathDiskInfo(TCHAR * pcPathName, TAG_PATH_INFO & pathInfo){	LS_RC lsRc = LS_RC_OK;		lsRc = LsSplitPath(pcPathName, pathInfo);	if(LS_RC_OK != lsRc)	{		goto _LsGetPathDiskInfo_END;	}_LsGetPathDiskInfo_END:	return lsRc;}LS_RC LsSplitPath(TCHAR * pcPathName, TAG_PATH_INFO & pathInfo){	LS_RC lsRc = LS_RC_OK;	if(!pathInfo.IsValid())	{		lsRc = MakeLsErrSn(LS_RC_PARAM_STRUCT_INVALID);		goto _LsSplitPath_END;	}	_tcscpy_s(pathInfo.PathInfo.path_buffer, SIZE_OF(pathInfo.PathInfo.path_buffer), pcPathName);	_tsplitpath_s(pathInfo.PathInfo.path_buffer, 		pathInfo.PathInfo.drive, SIZE_OF(pathInfo.PathInfo.drive),		pathInfo.PathInfo.dir, SIZE_OF(pathInfo.PathInfo.dir),		pathInfo.PathInfo.fname, SIZE_OF(pathInfo.PathInfo.fname),		pathInfo.PathInfo.ext, SIZE_OF(pathInfo.PathInfo.ext));_LsSplitPath_END:	return lsRc;}LS_RC LsGetFreeDiskSapce(TCHAR * pcPathName, TAG_DISK_FREE_SPACE & DiskFreeSapce){	BOOL bRc = TRUE;	LS_RC lsRc = LS_RC_OK;	TAG_PATH_INFO pathInfo;	ZeroMemory(&pathInfo, sizeof(TAG_PATH_INFO));	ZeroMemory(&DiskFreeSapce, sizeof(TAG_DISK_FREE_SPACE));	lsRc = LsSplitPath(pcPathName, pathInfo);	if(LS_RC_OK != lsRc)	{		goto _LsGetFreeDiskSapce_END;	}	_tcscpy_s(DiskFreeSapce.DiskFreeSpace.cRootPathName, SIZE_OF(DiskFreeSapce.DiskFreeSpace.cRootPathName), pathInfo.PathInfo.drive);	_tcscat_s(DiskFreeSapce.DiskFreeSpace.cRootPathName, SIZE_OF(DiskFreeSapce.DiskFreeSpace.cRootPathName), pathInfo.PathInfo.dir);	/** 给定的全路径必须存在 */	lsRc = LsFindFile(DiskFreeSapce.DiskFreeSpace.cRootPathName);	if(LS_RC_OK != lsRc)	{		goto _LsGetFreeDiskSapce_END;	}	bRc = GetDiskFreeSpace(DiskFreeSapce.DiskFreeSpace.cRootPathName, 		&DiskFreeSapce.DiskFreeSpace.dwSectorsPerCluster,		&DiskFreeSapce.DiskFreeSpace.dwBytesPerSector,		&DiskFreeSapce.DiskFreeSpace.dwNumberOfFreeClusters,		&DiskFreeSapce.DiskFreeSpace.dwTotalNumberOfClusters);	if(!bRc)	{		lsRc = MakeLsErrSn(LS_RC_GET_SYSTEM_INFO);		goto _LsGetFreeDiskSapce_END;	}	bRc = GetDiskFreeSpaceEx(DiskFreeSapce.DiskFreeSpace.cRootPathName, 		&DiskFreeSapce.DiskFreeSpace.ullFreeBytesAvailable, 		&DiskFreeSapce.DiskFreeSpace.ullTotalNumberOfBytes, 		&DiskFreeSapce.DiskFreeSpace.ullTotalNumberOfFreeBytes);	if(!bRc)	{		lsRc = MakeLsErrSn(LS_RC_GET_SYSTEM_INFO);		goto _LsGetFreeDiskSapce_END;	}_LsGetFreeDiskSapce_END:	return lsRc;}LS_RC LsGetWriteBufferLenForWirteFileNoCache(TCHAR * pcPathName, DWORD dwBytesOnceWriteMax, DWORD & dwWirteBufLen){	LS_RC lsRc = LS_RC_OK;	CONST DWORD dwInValid = -1;	TAG_DISK_FREE_SPACE DiskFreeSpace;	DWORD dwBytesPerSector = 0;/**< pcPathName所在磁盘每扇区size */	DWORD dwSectorCnt = 0;/**< 写nBytesOnceWriteMax所需的扇区数量 */	size_t nBytesModSector = 0;/**< 写nBytesOnceWriteMax所需的扇区数量之外的零头 */	if(dwInValid == dwBytesOnceWriteMax)	{		lsRc = MakeLsErrSn(LS_RC_PARAM_INVALID);		goto _LsGetWriteBufferLenForWirteFileNoCache_END;	}	ZeroMemory(&DiskFreeSpace, sizeof(TAG_DISK_FREE_SPACE));	lsRc = LsGetFreeDiskSapce(pcPathName, DiskFreeSpace);	if(LS_RC_OK != lsRc)	{		goto _LsGetWriteBufferLenForWirteFileNoCache_END;	}	dwBytesPerSector = DiskFreeSpace.DiskFreeSpace.dwBytesPerSector;	nBytesModSector = dwBytesOnceWriteMax % dwBytesPerSector;	dwSectorCnt = (dwBytesOnceWriteMax - nBytesModSector) / dwBytesPerSector;	if(nBytesModSector > 0)	{		dwSectorCnt++;	}	dwWirteBufLen = dwBytesPerSector * dwSectorCnt;_LsGetWriteBufferLenForWirteFileNoCache_END:	return lsRc;}LS_RC LsGetSectorMultiple(DWORD dwBytesUpperLimit, DWORD dwByteSectorBase, DWORD &dwSectorMultiple){	LS_RC lsRc = LS_RC_OK;	DWORD dwMod = dwByteSectorBase % dwBytesUpperLimit;	DWORD dwMultiple = (dwBytesUpperLimit - dwMod) / dwByteSectorBase;	dwSectorMultiple = dwMultiple * dwByteSectorBase;END:	return lsRc;}LS_RC LsGetWinOsPath(tstring & strPathName){	LS_RC lsRc = LS_RC_OK;	TCHAR cInfoBuf[LS_INFO_BUFFER_SIZE];	ZeroMemory(cInfoBuf, sizeof(cInfoBuf));	if(!GetWindowsDirectory(cInfoBuf, LS_INFO_BUFFER_SIZE))	{		lsRc = MakeLsErrSn(LS_RC_GET_SYSTEM_INFO);		goto _LsGetWinOsPath_END;	}	strPathName = cInfoBuf;_LsGetWinOsPath_END:	return lsRc;}LS_RC LsGetFullPathFromPathName(TCHAR * pcPathName, tstring & strPath){	/**< 从全路径文件名中, 得到全路径 */	LS_RC lsRc = LS_RC_OK;	return lsRc;}LS_RC LsCreateFullPath(TCHAR * pcFullPath){	/**< 建立给定的全路径目录 */	LS_RC lsRc = LS_RC_OK;	TAG_PATH_INFO pathInfo;	tstring strFullPath;	std::vector
    
      vecPath;	ZeroMemory(&pathInfo, sizeof(TAG_PATH_INFO));	lsRc = LsSplitPath(pcFullPath, pathInfo);	if(LS_RC_OK != lsRc)	{		goto END;	}	/** 给出的磁盘名称必须是物理存在的, 这个不能手工建立 */	lsRc = LsFindFile(pathInfo.PathInfo.drive);	if(LS_RC_OK != lsRc)	{		goto END;	}	/** 如果全路径已经存在, 不再去分析, 建立全路径 */	strFullPath = pathInfo.PathInfo.drive;	strFullPath += _T('\\');	strFullPath += pathInfo.PathInfo.dir;	lsRc = LsFindFile(strFullPath.c_str());	if(LS_RC_OK == lsRc)	{		goto END;	}	/** 切分全路径到vector */	lsRc = LsSplitPathToVector(pathInfo.PathInfo.dir, vecPath);	if(LS_RC_OK != lsRc)	{		goto END;	}	/** 建立多级目录 */	lsRc = LsCreateFullPath(pathInfo.PathInfo.drive, vecPath);	if(LS_RC_OK != lsRc)	{		goto END;	}END:	return lsRc;}LS_RC LsCreateFullPath(TCHAR * pcDriverName, std::vector
     
       & vecPath){	INT iRc = 0;	INT iLastErr = 0;	LS_RC lsRc = LS_RC_OK;	tstring strDir = pcDriverName;	std::vector
      
       ::iterator it = vecPath.begin();	for(it = vecPath.begin(); it != vecPath.end(); it++)	{		if(_T('\\') != strDir.at(strDir.length() - 1))		{			strDir += '\\';		}		strDir += *it;		iRc = _tmkdir(strDir.c_str());		//_tmkdir返回的东西不对啊, 和MSDN上说得不一样, 先忽略// 		iLastErr = GetLastError();// 		if((0 != iRc) && (EEXIST != GetLastError()))// 		{// 			lsRc = MakeLsErrSn(LS_RC_ERR_FILE_CREATE);// 			goto _LsCreateFullPath_pcDriverName_vecPath_END;// 		}		/** 换种方法判断是否建立文件夹成功, 原来就存在, 也算成功 */		lsRc = LsFindFile(strDir.c_str());		if(LS_RC_OK != lsRc)		{			lsRc = MakeLsErrSn(LS_RC_ERR_FILE_CREATE);			goto END;		}	}END:	return lsRc;}LS_RC LsSplitPathToVector(TCHAR * pcFullPath, std::vector
       
         & vecPath){	LS_RC lsRc = LS_RC_OK;	tstring strFullPath = pcFullPath;	tstring strSubDirName = _T("");	size_t nPosFind = 0;	size_t nPosBegin = -1;	size_t nPosEnd = -1;	size_t nSize = _tcslen(strFullPath.c_str());	do	{		nPosFind = strFullPath.find(_T('\\'), nPosFind);		if(nPosFind != -1)		{			nPosBegin = nPosEnd;			nPosEnd = nPosFind;			if((nPosBegin != nPosEnd) && (-1 != nPosBegin) && (-1 != nPosEnd) && (nPosEnd > nPosBegin))			{				strSubDirName = strFullPath.substr(nPosBegin + 1, nPosEnd - nPosBegin - 1);				vecPath.push_back(strSubDirName.c_str());			}		}		nPosFind++;	}	while((nPosFind != -1) && (nPosFind < nSize));	return lsRc;}LS_RC LsWriteFileNoCache(TAG_WIRTE_BUF_NO_CACHE_INFO & sWriteBufNoCache){	LS_RC lsRc = LS_RC_OK;	DWORD dwLenWriteOnce = 0;	DWORD dwLenWriteBack = 0;	DWORD dwPosToWriteSrc = 0;//源缓冲区要写入到块的位置	//如果要写入的长度 + 块写入当前位置 >= 无缓冲写入块长度, 向文件中循环写入块	while((sWriteBufNoCache.dwLenToWrite + sWriteBufNoCache.dwPosToWrite) >= sWriteBufNoCache.dwLenBufNoCache)	{		dwLenWriteOnce = sWriteBufNoCache.dwLenBufNoCache - sWriteBufNoCache.dwPosToWrite;		memcpy(sWriteBufNoCache.pBufNoCache + sWriteBufNoCache.dwPosToWrite, sWriteBufNoCache.pBufToWrite, dwLenWriteOnce);		dwPosToWriteSrc += dwLenWriteOnce;		sWriteBufNoCache.dwLenToWrite -= dwLenWriteOnce;		sWriteBufNoCache.dwPosToWrite = 0;		if(!WriteFile(sWriteBufNoCache.hFileToWrite, sWriteBufNoCache.pBufNoCache, sWriteBufNoCache.dwLenBufNoCache, &dwLenWriteBack, NULL))		{			lsRc = MakeLsErrSn(LS_RC_ERR_FILE_WRITE);			goto END;		}		/** 将数据写进文件, 要不一个空文件摆在那半天没动静, 像挂掉了一样 */		if(!FlushFileBuffers(sWriteBufNoCache.hFileToWrite))		{			lsRc = MakeLsErrSn(LS_RC_ERR_FILE_WRITE);			goto END;		}		sWriteBufNoCache.dwLenWrBack += dwLenWriteOnce;		sWriteBufNoCache.llTotalWriteIn += dwLenWriteOnce;	}	//移动不足一块的数据到写入块, 更新给调用者的回答	memcpy(sWriteBufNoCache.pBufNoCache + sWriteBufNoCache.dwPosToWrite, sWriteBufNoCache.pBufToWrite + dwPosToWriteSrc, sWriteBufNoCache.dwLenToWrite);	sWriteBufNoCache.dwPosToWrite += sWriteBufNoCache.dwLenToWrite;		//更新无缓冲块当前写入位置, 用于下次写入	sWriteBufNoCache.dwLenWrBack += sWriteBufNoCache.dwLenToWrite;		//更新调用者本次调用写入数量	sWriteBufNoCache.llTotalWriteIn += sWriteBufNoCache.dwLenToWrite;	//更新总写入数量, 用于确定文件总SizeEND:	return lsRc;}/** 最后一次的写, 然后调用关闭文件句柄 */LS_RC LsWriteFileNoCache_FulshData(TAG_WIRTE_BUF_NO_CACHE_INFO & sWriteBufNoCache){	LS_RC lsRc = LS_RC_OK;	DWORD dwLenWriteOnce = 0;	DWORD dwLenWriteBack = 0;	dwLenWriteOnce = sWriteBufNoCache.dwLenBufNoCache - sWriteBufNoCache.dwPosToWrite;	if(dwLenWriteOnce > 0)	{		sWriteBufNoCache.dwPosToWrite = 0;		if(!WriteFile(sWriteBufNoCache.hFileToWrite, sWriteBufNoCache.pBufNoCache, sWriteBufNoCache.dwLenBufNoCache, &dwLenWriteBack, NULL))		{			lsRc = MakeLsErrSn(LS_RC_ERR_FILE_WRITE);			goto END;		}		sWriteBufNoCache.dwLenWrBack += dwLenWriteOnce;		/** 		* 在LsWriteFileNoCache中, 已经对每次写入的字节数做了回应, 已经是正确的总长度,		* 最后一次写入不再更新 sWriteBufNoCache.llTotalWriteIn 		*/		//sWriteBufNoCache.llTotalWriteIn += dwLenWriteOnce;	}END:	return lsRc;}LS_RC LsSetFilePointer(TAG_WIRTE_BUF_NO_CACHE_INFO & sWriteBufNoCache){	LS_RC lsRc = LS_RC_OK;	//LONG_MAX	0x7fffffff	long	LONG lDistanceToMove = (LONG)(sWriteBufNoCache.llTotalWriteIn & LONG_MAX);	LONG lDistanceToMoveHigh = (LONG)(sWriteBufNoCache.llTotalWriteIn >> 31);	LONGLONG ullFileSize = sWriteBufNoCache.llTotalWriteIn;	if(INVALID_SET_FILE_POINTER == SetFilePointer(sWriteBufNoCache.hFileToWrite, lDistanceToMove, &lDistanceToMoveHigh, FILE_BEGIN))	{		lsRc = MakeLsErrSn(LS_RC_ERR_FILE_WRITE);		goto END;	}	if(!SetEndOfFile(sWriteBufNoCache.hFileToWrite))	{		lsRc = MakeLsErrSn(LS_RC_ERR_FILE_WRITE);		goto END;	}END:	return lsRc;}LS_NAMESPACE_END
       
      
     
    
   

demo上传位置:  FileOptNoCache_V2011_0725_0202.rar

<2011_0801>

遇到了奇怪问题，无缓冲区读文件时总是失败. 最后发现, 无缓冲区读，也是要读扇区倍数的字节数.  用无缓冲区方法写文件时，写完扇区倍数字节完成后，因为文件一般都不是扇区倍数字节的，最后要用SetFilePointer和EndOfFile来确定正确的文件Size. 读这种带零头的文件时，实际操作时怎样的呢?  有时间再做实验。 无缓冲区读写，不知道什么样的实际场景非要使用无缓冲区读写。 真不方便。

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