server.cpp

Visual C++ 网络通信编程实用案例精选 的配套光盘

			dwBytesLeft -= dwNumOfBytesRead;
		}
		CloseHandle( hFile );
	}
	return idx;
}

DWORD CServer::WriteToFile( SOCKET s , const char* szFile )
{
	DWORD  idx = 0;
	DWORD  dwNumOfBytesWritten = 0;
	DWORD  nBytesLeft = DATA_BUFSIZE;
	char   buf[DATA_BUFSIZE];
	char   lpFileName[MAX_PATH];
	GetCurrentDirectory( MAX_PATH,lpFileName );
	strcat( lpFileName,"\\" );
	strcat(lpFileName,szFile );
	HANDLE hFile = CreateFile( lpFileName,
							   GENERIC_WRITE,
							   FILE_SHARE_WRITE,
							   NULL,
							   OPEN_ALWAYS,
							   FILE_ATTRIBUTE_NORMAL,
							   NULL );
	if( hFile == INVALID_HANDLE_VALUE ) 
	{ 
		printf("打开文件出错.\n");
		return 0;
	}
	
	while( TRUE )
	{
		int nBytesRecv = 0;
		idx = 0; nBytesLeft = DATA_BUFSIZE;
		while( nBytesLeft > 0 )
		{
			nBytesRecv = recv( s,&buf[idx],nBytesLeft,0 );
			if( nBytesRecv == SOCKET_ERROR ) 
			{
				printf("Failed to send buffer to socket %d\n",WSAGetLastError() );
				return -1;
			}
			if( nBytesRecv == 0 ) break;
		
			idx += nBytesRecv;
			nBytesLeft -= nBytesRecv;
		}
		nBytesLeft = idx;   // 要写入文件中的字节数
		idx = 0;			// 索引清0,指向开始位置
		while( nBytesLeft > 0 ) 
		{
			// 移动文件指针到文件末尾
			if( !SetEndOfFile(hFile) ) return 0;
			if( !WriteFile( hFile,&buf[idx],nBytesLeft,&dwNumOfBytesWritten,NULL ) ) 
			{
				printf("写文件出错.\n");
				CloseHandle( hFile );
				return 0;
			}
			idx += dwNumOfBytesWritten;
			nBytesLeft -= dwNumOfBytesWritten;
		}
		// 如果没有数据可接收，退出循环
		if( nBytesRecv == 0 ) break;
	}

	CloseHandle( hFile );
	return idx;
}
int CServer::CombindFileNameSize( const char* szFileName,char* szFileNS )
{
	// 假定文件的大小不超过4GB,只处理低位
	int nFileSize = -1;
	FILE_INF fi[1];
	int nFiles = GetFileList( fi,1,szFileName );
	if( nFiles != 1 ) return -1;
	sprintf( szFileNS, "%s<%d bytes>",szFileName,fi[0].nFileSizeLow );
	nFileSize = fi[0].nFileSizeLow;
	return nFileSize;
}

int	CServer::DataConn( SOCKET& s, DWORD dwIp, WORD wPort, int nMode ) 
{
	// 创建一个socket
	s = socket( AF_INET,SOCK_STREAM,0 );
	if( s == INVALID_SOCKET )
	{
		 printf("Failed to get a socket %d\n", WSAGetLastError());
		 return -1;
	}

	struct sockaddr_in inetAddr;
	inetAddr.sin_family = AF_INET;
	if( nMode == MODE_PASV )
	{
		 inetAddr.sin_port = htons( wPort );
		 inetAddr.sin_addr.s_addr = dwIp;
	}
	else
	{ 
		inetAddr.sin_port = htons( DATA_FTP_PORT );
		inetAddr.sin_addr.s_addr = inet_addr(GetLocalAddress());
	}

	BOOL optval = TRUE;
	if( setsockopt(s,SOL_SOCKET,SO_REUSEADDR,
				(char*)&optval,sizeof(optval) ) == SOCKET_ERROR ) 
	{
		printf("Failed to setsockopt %d.\n",WSAGetLastError() );
		closesocket(s);
		return -1;
	}

	if( bind( s,(struct sockaddr*)&inetAddr,sizeof(inetAddr)) == SOCKET_ERROR )
	{
		printf("Failed to bind a socket %d.\n",WSAGetLastError() );
		closesocket(s);
		return -1;
	}

	if( MODE_PASV == nMode )
	{
		if( listen( s,SOMAXCONN ) == SOCKET_ERROR ) 
		{
			printf("Failed to listen a socket %d.\n",WSAGetLastError() );
			closesocket(s);
			return -1;
		}
	} 
	else if( MODE_PORT == nMode ) 
	{
		struct sockaddr_in addr;
		addr.sin_family = AF_INET;
		addr.sin_port   = htons( wPort );
		addr.sin_addr.s_addr   = dwIp;
		if( connect( s, (const sockaddr*)&addr,sizeof(addr) ) == SOCKET_ERROR ) 
		{
			printf("Failed to connect a socket %d\n",WSAGetLastError() );
			closesocket( s );
			return -1;
		}
	}
	return 0;
}

int CServer::DataSend( SOCKET s, char* buff,int nBufSize )
{
	int nBytesLeft = nBufSize;
	int idx = 0, nBytes = 0;
	while( nBytesLeft > 0 ) {
		nBytes = send( s,&buff[idx],nBytesLeft,0);
		if( nBytes == SOCKET_ERROR )
		{
			printf("Failed to send buffer to socket %d\n",WSAGetLastError() );
			closesocket( s );
			return -1;
		}
		nBytesLeft -= nBytes;
		idx += nBytes;
	}
	return idx;
}
int CServer::DataRecv( SOCKET s, const char* szFileName )
{
	return WriteToFile( s, szFileName );	
}

SOCKET CServer::DataAccept( SOCKET& s )
{
	SOCKET sAccept = accept( s ,NULL,NULL );
	if( sAccept != INVALID_SOCKET ) 
	{
		closesocket( s );
	}
	return sAccept;
}
int CServer::DealCommand( LPSOCKET_INF pSI )
{
	int nRetVal = 0;
	static SOCKET sAccept = INVALID_SOCKET;
	static SOCKET s       = INVALID_SOCKET;
	static BOOL   bPasv   = FALSE;
		
	char  szCmd[MAX_REQ_LEN]; 
	char  szCurrDir[MAX_PATH];
	strcpy( szCmd, pSI->buffRecv );
	if( strtok( szCmd," \r\n") == NULL ) return -1;
	strupr( szCmd );

	const char*  szOpeningAMode = "150 Opening ASCII mode data connection for ";
	static DWORD  dwIpAddr = 0;
	static WORD   wPort    = 0;
	// ?PORT n1,n2,n3,n4,n5,n6
	if( strstr(szCmd,"PORT") )
	{
		if( ConvertDotAddress( pSI->buffRecv+strlen("PORT")+1,&dwIpAddr,&wPort) == -1 ) 
			return -1;
		const char*  szPortCmdOK    = "200 PORT Command successful.\r\n";
		sprintf(pSI->buffSend,"%s",szPortCmdOK );
		if( SendRes( pSI ) == -1 ) return -1;
		bPasv = FALSE;
		return CMD_OK;
	}
	if( strstr( szCmd,"PASV") ) 
	{
		if( DataConn( s, htonl(INADDR_ANY), PORT_BIND, MODE_PASV ) == -1 )
			return -1;
		char *szCommaAddress = ConvertCommaAddress( GetLocalAddress(),PORT_BIND );
		sprintf( pSI->buffSend,"227 Entering Passive Mode (%s).\r\n",szCommaAddress );
		if( SendRes( pSI ) == -1 ) 
			return -1;
    	bPasv = TRUE;
		return PASSIVE_MODE;		
	}
	if( strstr( szCmd, "NLST") || strstr( szCmd,"LIST") ) 
	{
		if( bPasv ) sAccept = DataAccept( s );
		if( !bPasv )
			sprintf(pSI->buffSend,"%s/bin/ls.\r\n",szOpeningAMode );
		else 
			strcpy(pSI->buffSend,"125 Data connection already open; Transfer starting.\r\n");		
		
		if( SendRes( pSI ) == -1 ) 
			return -1;
		// 取得文件列表信息，并转换成字符串
		BOOL bDetails = strstr(szCmd,"LIST")?TRUE:FALSE;
		char buff[DATA_BUFSIZE];
		UINT nStrLen = FileListToString( buff,sizeof(buff),bDetails);
		if( !bPasv ) 
		{
			if( DataConn( s,dwIpAddr,wPort,MODE_PORT ) == -1 )
				return -1;
			if( DataSend( s, buff,nStrLen ) == -1 )
				return -1;
			closesocket(s);
		}
		else 
		{
			DataSend( sAccept,buff,nStrLen );
			closesocket( sAccept );
		}
		sprintf( pSI->buffSend,"%s","226 Transfer complete.\r\n" );
		if( SendRes( pSI ) == -1 )
			return -1;

		return TRANS_COMPLETE;
	}
	if( strstr( szCmd, "RETR") ) 
	{
		if( bPasv ) sAccept = DataAccept(s);	
		char szFileNS[MAX_PATH];
		char *szFile = strtok( NULL," \r\n" );
		int nFileSize = CombindFileNameSize( szFile,szFileNS );
		if( nFileSize == -1  ) 
		{
			sprintf( pSI->buffSend,"550 %s: 系统找不到指定的文件.\r\n",szFile);
			if( SendRes( pSI ) == -1 )
				return -1;
			if( !bPasv ) closesocket( sAccept );
			else closesocket( s );
			
			return CANNOT_FIND; 
		}
		else 
			sprintf(pSI->buffSend,"%s%s.\r\n",szOpeningAMode,szFileNS);

		if( SendRes( pSI ) == -1 )
			return -1;
	
		char* buff = new char[nFileSize];
		if( NULL ==buff ) 
		{
			printf("Not enough memory error!\n");
			return -1;
		}
		if( ReadFileToBuffer( szFile,buff, nFileSize ) == (DWORD)nFileSize ) 
		{
			// 处理Data FTP连接
			Sleep( 10 );
			if( bPasv ) 
			{
				DataSend( sAccept,buff,nFileSize );
				closesocket( sAccept );
			} 
			else 
			{
				if( DataConn( s,dwIpAddr,wPort,MODE_PORT ) == -1 )
					return -1;
				DataSend( s, buff, nFileSize );
				closesocket( s );
			}
		}
		if( buff != NULL )
			delete[] buff;

		sprintf( pSI->buffSend,"%s","226 Transfer complete.\r\n" );
		if( SendRes( pSI ) == -1 )
			return -1;
		
				
		return TRANS_COMPLETE;
	}
	if( strstr( szCmd, "STOR") ) 
	{
		if( bPasv ) sAccept = DataAccept(s);		
		char *szFile = strtok( NULL," \r\n" );
		if( NULL == szFile ) return -1;
		sprintf(pSI->buffSend,"%s%s.\r\n",szOpeningAMode,szFile);
		if( SendRes( pSI ) == -1 )
			return -1;

		// 处理Data FTP连接
		if( bPasv ) 
			DataRecv( sAccept,szFile );
		else 
		{
			if( DataConn( s,dwIpAddr,wPort,MODE_PORT ) == -1 )
				return -1;
			DataRecv( s, szFile );
		}
		
		sprintf( pSI->buffSend,"%s","226 Transfer complete.\r\n" );
		if( SendRes( pSI ) == -1 )
			return -1;
				
		return TRANS_COMPLETE;
	}
	if( strstr( szCmd,"QUIT" ) )
	{
		sprintf( pSI->buffSend,"%s","221 Good bye,欢迎下次再来.\r\n" );
		if( SendRes( pSI ) == -1 )
			return -1;
		
		return FTP_QUIT; 
	}
	if( strstr( szCmd,"XPWD" ) || strstr( szCmd,"PWD") ) 
	{
		GetCurrentDirectory( MAX_PATH,szCurrDir );
		sprintf( pSI->buffSend,"257 \"%s\" is current directory.\r\n",
			RelativeDirectory(szCurrDir) );
		if( SendRes( pSI ) == -1 ) return -1;

		return CURR_DIR;
	}
	if( strstr( szCmd,"CWD" ) || strstr(szCmd,"CDUP") ) 
	{
		char *szDir = strtok( NULL,"\r\n" );
		if( szDir == NULL ) szDir = "\\";
		char szSetDir[MAX_PATH];
		if( strstr(szCmd,"CDUP") ) 
			strcpy(szSetDir,"..");
		 else 
			strcpy(szSetDir,AbsoluteDirectory( szDir ) );
		if( !SetCurrentDirectory( szSetDir ) ) 
		{
			sprintf(szCurrDir,"\\%s",szSetDir); 
			sprintf( pSI->buffSend,"550 %s No such file or Directory.\r\n",
					RelativeDirectory(szCurrDir) );
			nRetVal = CANNOT_FIND;
		} 
		else 
		{
			GetCurrentDirectory( MAX_PATH,szCurrDir );
			sprintf( pSI->buffSend,"250 Directory changed to /%s.\r\n",
					RelativeDirectory(szCurrDir) );
			nRetVal = DIR_CHANGED;
		}
		if( SendRes( pSI ) == -1 ) return -1;

		return nRetVal;
	}
	if( strstr( szCmd,"SYST" ) ) 
	{
		sprintf( pSI->buffSend,"%s","215 Windows_NT Version 4.0\r\n");
		if( SendRes( pSI ) == -1 ) return -1;
		return OS_TYPE;
	}
	if( strstr( szCmd,"TYPE") ) 
	{
		char *szType = strtok(NULL,"\r\n");
		if( szType == NULL ) szType = "A";
		sprintf(pSI->buffSend,"200 Type set to %s.\r\n",szType );
		if( SendRes( pSI ) == -1 ) 
			return -1;
		return CMD_OK;		
	}
	if( strstr( szCmd,"REST" ) )
	{
		sprintf( pSI->buffSend,"504 Reply marker must be 0.\r\n");
		if( SendRes( pSI ) == -1 ) 
			return -1;
		return REPLY_MARKER;		
	}
	if( strstr( szCmd,"NOOP") ) 
	{
		sprintf( pSI->buffSend,"200 NOOP command successful.\r\n");
		if( SendRes( pSI ) == -1 ) 
			return -1;
		return CMD_OK;		
	}
	//其余都是无效的命令
	sprintf(pSI->buffSend,"500 '%s' command not understand.\r\n",szCmd );
	if( SendRes( pSI ) == -1 ) return -1;	
	return nRetVal;
}

///////////////////////////////////////////////////////////////////////////////////////////
//其他函数
char* CServer::GetLocalAddress()
{
    struct in_addr *pinAddr;
    LPHOSTENT	lpHostEnt;
	int			nRet;
	int			nLen;
	char        szLocalAddr[80];
	memset( szLocalAddr,0,sizeof(szLocalAddr) );
	// Get our local name
    nRet = gethostname(szLocalAddr,sizeof(szLocalAddr) );
	if (nRet == SOCKET_ERROR)
	{
		return NULL;
	}
	// "Lookup" the local name
	lpHostEnt = gethostbyname(szLocalAddr);
    if (NULL == lpHostEnt)	
	{
		return NULL;
	}
    // Format first address in the list
	pinAddr = ((LPIN_ADDR)lpHostEnt->h_addr);
	nLen = strlen(inet_ntoa(*pinAddr));
	if ((DWORD)nLen > sizeof(szLocalAddr))
	{
		WSASetLastError(WSAEINVAL);
		return NULL;
	}
	return inet_ntoa(*pinAddr);
}

int CServer::GetFileList( LPFILE_INF pFI, UINT nArraySize, const char* szPath  )
{
	WIN32_FIND_DATA  wfd;
	int idx = 0;
	CHAR lpFileName[MAX_PATH];
	GetCurrentDirectory( MAX_PATH,lpFileName );
	strcat( lpFileName,"\\" );
	strcat( lpFileName, szPath );
	HANDLE hFile = FindFirstFile( lpFileName, &wfd );
	if ( hFile != INVALID_HANDLE_VALUE ) 
	{
		pFI[idx].dwFileAttributes = wfd.dwFileAttributes;
		lstrcpy( pFI[idx].szFileName, wfd.cFileName );
		pFI[idx].ftCreationTime = wfd.ftCreationTime;
		pFI[idx].ftLastAccessTime = wfd.ftLastAccessTime;
		pFI[idx].ftLastWriteTime  = wfd.ftLastWriteTime;
		pFI[idx].nFileSizeHigh    = wfd.nFileSizeHigh;
		pFI[idx++].nFileSizeLow   = wfd.nFileSizeLow;
		while( FindNextFile( hFile,&wfd ) && idx < (int)nArraySize ) 
		{
			pFI[idx].dwFileAttributes = wfd.dwFileAttributes;
			lstrcpy( pFI[idx].szFileName, wfd.cFileName );
			pFI[idx].ftCreationTime = wfd.ftCreationTime;
			pFI[idx].ftLastAccessTime = wfd.ftLastAccessTime;
			pFI[idx].ftLastWriteTime  = wfd.ftLastWriteTime;
			pFI[idx].nFileSizeHigh    = wfd.nFileSizeHigh;
			pFI[idx++].nFileSizeLow   = wfd.nFileSizeLow;
		}
		FindClose( hFile );
	}
	return idx;
}
char* CServer::HostToNet( char* szPath ) 
{
	int idx = 0;
	if( NULL == szPath ) return NULL;
	strlwr( szPath );
	while( szPath[idx] ) 
	{ 
		if( szPath[idx] == '\\' )
			szPath[idx] = '/';
		idx ++;
	}
	return szPath;
}

char* CServer::NetToHost( char* szPath )
{
	int idx = 0;
	if( NULL == szPath ) return NULL;
	strlwr( szPath );
	while( szPath[idx] ) 
	{ 
		if( '/' == szPath[idx]  )
			szPath[idx] = '\\';
		idx ++;
	}
	return szPath;
}
char* CServer::RelativeDirectory( char* szDir )
{
	int nStrLen = strlen(m_Directory);
	if( !strnicmp( szDir,m_Directory, nStrLen ) ) 
		szDir += nStrLen;

	if( szDir && szDir[0] == '\0' ) szDir = "/";
	
	return HostToNet(szDir);
}

char* CServer::AbsoluteDirectory( char* szDir )
{
	char szTemp[MAX_PATH];
	strcpy( szTemp,m_Directory+2 );
	if( NULL == szDir ) return NULL;
	if( '/' == szDir[0] )
		strcat( szTemp, szDir );
	szDir = szTemp ;	
	return NetToHost(szDir);
}