iocpserver.cpp

应用完成端口进行tcp的连接

    // clients connecting and then not sending or receiving, the server
    // should maintain a timer on each connection. If after some point,
    // the server deems a connection is "stale" it can then set linger
    // to be abortive and close the connection.
    //

    /*
	LINGER lingerStruct;

	lingerStruct.l_onoff = 1;
	lingerStruct.l_linger = 0;

	nRet = setsockopt(g_sdListen, SOL_SOCKET, SO_LINGER,
					  (char *)&lingerStruct, sizeof(lingerStruct) );
	if( nRet == SOCKET_ERROR ) {
		myprintf("setsockopt(SO_LINGER) failed: %d\n", WSAGetLastError());
		return(FALSE);
	}
    */

	freeaddrinfo(addrlocal);

	return(TRUE);
}

//
// Worker thread that handles all I/O requests on any socket handle added to the IOCP.
//
DWORD WINAPI WorkerThread (LPVOID WorkThreadContext) {

	HANDLE hIOCP = (HANDLE)WorkThreadContext;
	BOOL bSuccess = FALSE;
	int nRet = 0;
	LPWSAOVERLAPPED lpOverlapped = NULL;
	PPER_SOCKET_CONTEXT lpPerSocketContext = NULL;
	PPER_IO_CONTEXT lpIOContext = NULL; 
	WSABUF buffRecv;
	WSABUF buffSend;
	DWORD dwRecvNumBytes = 0;
	DWORD dwSendNumBytes = 0;
	DWORD dwFlags = 0;
	DWORD dwIoSize = 0;

	while( TRUE ) {

        //
		// continually loop to service io completion packets
		//
		bSuccess = GetQueuedCompletionStatus(hIOCP, &dwIoSize,
											 (PDWORD_PTR)&lpPerSocketContext,
											 (LPOVERLAPPED *)&lpOverlapped, 
											 INFINITE);
		if( !bSuccess )
			myprintf("GetQueuedCompletionStatus() failed: %d\n", GetLastError());

		if( lpPerSocketContext == NULL ) {

			//
			// CTRL-C handler used PostQueuedCompletionStatus to post an I/O packet with
			// a NULL CompletionKey (or if we get one for any reason).  It is time to exit.
			//
			return(0);
		}

		if( g_bEndServer ) {

			//
			// main thread will do all cleanup needed - see finally block
			//
			return(0);
		}

		if( !bSuccess || (bSuccess && (dwIoSize == 0)) ) {

			//
			// client connection dropped, continue to service remaining (and possibly 
			// new) client connections
			//
			CloseClient(lpPerSocketContext, FALSE); 
			continue;
		}

        //
		// determine what type of IO packet has completed by checking the PER_IO_CONTEXT 
		// associated with this socket.  This will determine what action to take.
		//
		lpIOContext = (PPER_IO_CONTEXT)lpOverlapped;
		switch( lpIOContext->IOOperation ) {
		case ClientIoRead:

			//
			// a read operation has completed, post a write operation to echo the
			// data back to the client using the same data buffer.
			//
			lpIOContext->IOOperation = ClientIoWrite;
			lpIOContext->nTotalBytes = dwIoSize;
			lpIOContext->nSentBytes  = 0;
			lpIOContext->wsabuf.len  = dwIoSize;
			dwFlags = 0;
			nRet = WSASend(lpPerSocketContext->Socket, &lpIOContext->wsabuf, 1, 
						   &dwSendNumBytes, dwFlags, &(lpIOContext->Overlapped), NULL);
			if( nRet == SOCKET_ERROR && (ERROR_IO_PENDING != WSAGetLastError()) ) {
				myprintf("WSASend() failed: %d\n", WSAGetLastError());
				CloseClient(lpPerSocketContext, FALSE);
			} else if( g_bVerbose ) {
				myprintf("WorkerThread %d: Socket(%d) Recv completed (%d bytes), Send posted\n", 
					   GetCurrentThreadId(), lpPerSocketContext->Socket, dwIoSize);
			}
			break;

		case ClientIoWrite:

			//
			// a write operation has completed, determine if all the data intended to be
			// sent actually was sent.
			//
			lpIOContext->IOOperation = ClientIoWrite;
			lpIOContext->nSentBytes  += dwIoSize;
			dwFlags = 0;
			if( lpIOContext->nSentBytes < lpIOContext->nTotalBytes ) {

				//
				// the previous write operation didn't send all the data,
				// post another send to complete the operation
				//
				buffSend.buf = lpIOContext->Buffer + lpIOContext->nSentBytes;
				buffSend.len = lpIOContext->nTotalBytes - lpIOContext->nSentBytes;
				nRet = WSASend (lpPerSocketContext->Socket, &buffSend, 1, 
								&dwSendNumBytes, dwFlags, &(lpIOContext->Overlapped), NULL);
				if( nRet == SOCKET_ERROR && (ERROR_IO_PENDING != WSAGetLastError()) ) {
					myprintf("WSASend() failed: %d\n", WSAGetLastError());
					CloseClient(lpPerSocketContext, FALSE);
				} else if( g_bVerbose ) {
					myprintf("WorkerThread %d: Socket(%d) Send partially completed (%d bytes), Recv posted\n", 
						   GetCurrentThreadId(), lpPerSocketContext->Socket, dwIoSize);
				}
			} else {

				//
				// previous write operation completed for this socket, post another recv
				//
				lpIOContext->IOOperation = ClientIoRead; 
				dwRecvNumBytes = 0;
				dwFlags = 0;
				buffRecv.buf = lpIOContext->Buffer,
				buffRecv.len = MAX_BUFF_SIZE;
				nRet = WSARecv(lpPerSocketContext->Socket, &buffRecv, 1, 
							   &dwRecvNumBytes, &dwFlags, &lpIOContext->Overlapped, NULL);
				if( nRet == SOCKET_ERROR && (ERROR_IO_PENDING != WSAGetLastError()) ) {
					myprintf("WSARecv() failed: %d\n", WSAGetLastError());
					CloseClient(lpPerSocketContext, FALSE);
				} else if( g_bVerbose ) {
					myprintf("WorkerThread %d: Socket(%d) Send completed (%d bytes), Recv posted\n", 
						   GetCurrentThreadId(), lpPerSocketContext->Socket, dwIoSize);
				}
			}
			break;

		} //switch
	} //while
	return(0);
} 

//
//  Allocate a context structures for the socket and add the socket to the IOCP.  
//  Additionally, add the context structure to the global list of context structures.
//
PPER_SOCKET_CONTEXT UpdateCompletionPort(SOCKET sd, IO_OPERATION ClientIo,
										 BOOL bAddToList) {

	PPER_SOCKET_CONTEXT lpPerSocketContext;

	lpPerSocketContext = CtxtAllocate(sd, ClientIo);
	if( lpPerSocketContext == NULL )
		return(NULL);

	g_hIOCP = CreateIoCompletionPort((HANDLE)sd, g_hIOCP, (DWORD_PTR)lpPerSocketContext, 0);
	if( g_hIOCP == NULL ) {
		myprintf("CreateIoCompletionPort() failed: %d\n", GetLastError());
		if( lpPerSocketContext->pIOContext )
			xfree(lpPerSocketContext->pIOContext);
		xfree(lpPerSocketContext);
		return(NULL);
	}

    //
	//The listening socket context (bAddToList is FALSE) is not added to the list.
	//All other socket contexts are added to the list.
	//
	if( bAddToList ) CtxtListAddTo(lpPerSocketContext);

	if( g_bVerbose )
		myprintf("UpdateCompletionPort: Socket(%d) added to IOCP\n", lpPerSocketContext->Socket);

	return(lpPerSocketContext);
}

//
//  Close down a connection with a client.  This involves closing the socket (when 
//  initiated as a result of a CTRL-C the socket closure is not graceful).  Additionally, 
//  any context data associated with that socket is free'd.
//
VOID CloseClient (PPER_SOCKET_CONTEXT lpPerSocketContext,
				  BOOL bGraceful) {

	EnterCriticalSection(&g_CriticalSection);

	if( lpPerSocketContext ) {
		if( g_bVerbose )
			myprintf("CloseClient: Socket(%d) connection closing (graceful=%s)\n",
				   lpPerSocketContext->Socket, (bGraceful?"TRUE":"FALSE"));
		if( !bGraceful ) {

			//
			// force the subsequent closesocket to be abortative.
			//
			LINGER  lingerStruct;

			lingerStruct.l_onoff = 1;
			lingerStruct.l_linger = 0;
			setsockopt(lpPerSocketContext->Socket, SOL_SOCKET, SO_LINGER,
					   (char *)&lingerStruct, sizeof(lingerStruct) );
		}
		closesocket(lpPerSocketContext->Socket);
		lpPerSocketContext->Socket = INVALID_SOCKET;
		CtxtListDeleteFrom(lpPerSocketContext);
		lpPerSocketContext = NULL;
	} else {
		myprintf("CloseClient: lpPerSocketContext is NULL\n");
	}

	LeaveCriticalSection(&g_CriticalSection);
	return;    
} 

//
// Allocate a socket context for the new connection.  
//
PPER_SOCKET_CONTEXT CtxtAllocate(SOCKET sd, IO_OPERATION ClientIO) {

	PPER_SOCKET_CONTEXT lpPerSocketContext;

	EnterCriticalSection(&g_CriticalSection);

	lpPerSocketContext = (PPER_SOCKET_CONTEXT)xmalloc(sizeof(PER_SOCKET_CONTEXT));
	if( lpPerSocketContext ) {
		lpPerSocketContext->pIOContext = (PPER_IO_CONTEXT)xmalloc(sizeof(PER_IO_CONTEXT));
		if( lpPerSocketContext->pIOContext ) {
			lpPerSocketContext->Socket = sd;
			lpPerSocketContext->pCtxtBack = NULL;
			lpPerSocketContext->pCtxtForward = NULL;

			lpPerSocketContext->pIOContext->Overlapped.Internal = 0;
			lpPerSocketContext->pIOContext->Overlapped.InternalHigh = 0;
			lpPerSocketContext->pIOContext->Overlapped.Offset = 0;
			lpPerSocketContext->pIOContext->Overlapped.OffsetHigh = 0;
			lpPerSocketContext->pIOContext->Overlapped.hEvent = NULL;
			lpPerSocketContext->pIOContext->IOOperation = ClientIO;
			lpPerSocketContext->pIOContext->pIOContextForward = NULL;
			lpPerSocketContext->pIOContext->nTotalBytes = 0;
			lpPerSocketContext->pIOContext->nSentBytes  = 0;
			lpPerSocketContext->pIOContext->wsabuf.buf  = lpPerSocketContext->pIOContext->Buffer;
			lpPerSocketContext->pIOContext->wsabuf.len  = sizeof(lpPerSocketContext->pIOContext->Buffer);

			ZeroMemory(lpPerSocketContext->pIOContext->wsabuf.buf, lpPerSocketContext->pIOContext->wsabuf.len);
		} else {
			xfree(lpPerSocketContext);
			myprintf("HeapAlloc() PER_IO_CONTEXT failed: %d\n", GetLastError());
		}

	} else {
		myprintf("HeapAlloc() PER_SOCKET_CONTEXT failed: %d\n", GetLastError());
	}

	LeaveCriticalSection(&g_CriticalSection);

	return(lpPerSocketContext);
} 

//
//  Add a client connection context structure to the global list of context structures.
//
VOID CtxtListAddTo (PPER_SOCKET_CONTEXT lpPerSocketContext) {

	PPER_SOCKET_CONTEXT     pTemp;

	EnterCriticalSection(&g_CriticalSection);

	if( g_pCtxtList == NULL ) {

		//
		// add the first node to the linked list
		//
		lpPerSocketContext->pCtxtBack    = NULL;
		lpPerSocketContext->pCtxtForward = NULL;
		g_pCtxtList = lpPerSocketContext;
	} else {

		//
		// add node to head of list
		//
		pTemp = g_pCtxtList;

		g_pCtxtList = lpPerSocketContext;
		lpPerSocketContext->pCtxtBack    = pTemp;
		lpPerSocketContext->pCtxtForward = NULL; 

		pTemp->pCtxtForward = lpPerSocketContext;
	}

	LeaveCriticalSection(&g_CriticalSection);
	return;
}

//
//  Remove a client context structure from the global list of context structures.
//
VOID CtxtListDeleteFrom(PPER_SOCKET_CONTEXT lpPerSocketContext) {

	PPER_SOCKET_CONTEXT pBack;
	PPER_SOCKET_CONTEXT pForward;
	PPER_IO_CONTEXT     pNextIO     = NULL;
	PPER_IO_CONTEXT     pTempIO     = NULL;

	EnterCriticalSection(&g_CriticalSection);

	if( lpPerSocketContext ) {
		pBack       = lpPerSocketContext->pCtxtBack;
		pForward    = lpPerSocketContext->pCtxtForward;


		if( ( pBack == NULL ) && ( pForward == NULL ) ) {

			//
			// This is the only node in the list to delete
			//
			g_pCtxtList = NULL;
		} else if ( ( pBack == NULL ) && ( pForward != NULL ) ) {

			//
			// This is the start node in the list to delete
			//
			pForward->pCtxtBack = NULL;
			g_pCtxtList = pForward;
		} else if ( ( pBack != NULL ) && ( pForward == NULL ) ) {

			//
			// This is the end node in the list to delete
			//
			pBack->pCtxtForward = NULL;
		} else if( pBack && pForward ) {

			//
			// Neither start node nor end node in the list
			//
			pBack->pCtxtForward = pForward;
			pForward->pCtxtBack = pBack;
		}

		//
		// Free all i/o context structures per socket
		//
		pTempIO = (PPER_IO_CONTEXT)(lpPerSocketContext->pIOContext);
		do {
			pNextIO = (PPER_IO_CONTEXT)(pTempIO->pIOContextForward);
			if( pTempIO ) {

				//
				//The overlapped structure is safe to free when only the posted i/o has
				//completed. Here we only need to test those posted but not yet received 
				//by PQCS in the shutdown process.
				//
				if( g_bEndServer )
					while( !HasOverlappedIoCompleted((LPOVERLAPPED)pTempIO) ) Sleep(0);
				xfree(pTempIO);
				pTempIO = NULL;
			}
			pTempIO = pNextIO;
		} while( pNextIO );

		xfree(lpPerSocketContext);
		lpPerSocketContext = NULL;

	} else {
		myprintf("CtxtListDeleteFrom: lpPerSocketContext is NULL\n");
	}

	LeaveCriticalSection(&g_CriticalSection);
	return;
}

//
//  Free all context structure in the global list of context structures.
//
VOID CtxtListFree() {

	PPER_SOCKET_CONTEXT     pTemp1, pTemp2;

	EnterCriticalSection(&g_CriticalSection);

	pTemp1 = g_pCtxtList; 
	while( pTemp1 ) {
		pTemp2 = pTemp1->pCtxtBack;
		CloseClient(pTemp1, FALSE);
		pTemp1 = pTemp2;
	}

	LeaveCriticalSection(&g_CriticalSection);
	return;
}

//
// Our own printf. This is done because calling printf from multiple
// threads can AV. The standard out for WriteConsole is buffered...
//
int myprintf (const char *lpFormat, ... ) {

	int nLen = 0;
	int nRet = 0;
	char cBuffer[512] ;
	va_list arglist ;
	HANDLE hOut = NULL;

	ZeroMemory(cBuffer, sizeof(cBuffer));

	va_start(arglist, lpFormat);

	nLen = lstrlen( lpFormat ) ;
	nRet = wvsprintf( cBuffer, lpFormat, arglist );

	if( nRet >= nLen || GetLastError() == 0 ) {
		hOut = GetStdHandle(STD_OUTPUT_HANDLE) ;
		if( hOut != INVALID_HANDLE_VALUE )
			WriteConsole( hOut, cBuffer, lstrlen(cBuffer), (LPDWORD)&nLen, NULL ) ;
	}

	return nLen ;
}