Socket IO模型详解.doc

Socket I/O模型之选择(select) 在windows平台构建网络应用，必须了解socket I/O模型。windows提供了选择(select)、异步选择(WSAAsyncSelect)、事件选择(WSAEventSelect)、重叠I /O(overlapped I/O)和完成端口(completion port)。 一、客户端代码 C+代码 #includestdafx.h #include #include #pragmacomment(lib,ws2_32.lib) #defineSERVER_ADDRESS192.168.10.56 #definePORT5150 #defineMSGSIZE1024 intmain(intargc,char*argv) WSADATAwsaData; SOCKETsClient; SOCKADDR_INserver; charszMessageMSGSIZE; intret; /Initializewindowssocketlibrary WSAStartup(0x0202,&wsaData); /Createclientsocket sClient=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP); /Connecttoserver memset(&server,0,sizeof(SOCKADDR_IN); server.sin_family=AF_INET; server.sin_addr.S_un.S_addr=inet_addr(SERVER_ADDRESS); server.sin_port=htons(PORT); connect(sClient,(sockaddr*)&server,sizeof(SOCKADDR_IN); while(TRUE) printf(Send:); gets(szMessage); /Sendmessage send(sClient,szMessage,strlen(szMessage),0); /Receivemessage ret=recv(sClient,szMessage,MSGSIZE,0); szMessageret=0; printf(Received%dbytes:%sn,ret,szMessage); /Cleanup closesocket(sClient); WSACleanup(); return0; #include stdafx.h#include #include #pragma comment(lib, ws2_32.lib)#define SERVER_ADDRESS 192.168.10.56#define PORT 5150#define MSGSIZE 1024int main(int argc, char* argv)WSADATA wsaData;SOCKET sClient;SOCKADDR_IN server;char szMessageMSGSIZE;int ret;/ Initialize windows socket libraryWSAStartup(0x0202, &wsaData);/ Create client socketsClient = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);/ Connect to servermemset(&server, 0, sizeof(SOCKADDR_IN);server.sin_family = AF_INET;server.sin_addr.S_un.S_addr = inet_addr(SERVER_ADDRESS);server.sin_port = htons(PORT);connect(sClient, (sockaddr*)&server, sizeof(SOCKADDR_IN);while (TRUE) printf(Send:);gets(szMessage);/ Send messagesend(sClient, szMessage, strlen(szMessage), 0);/ Receive messageret = recv(sClient, szMessage, MSGSIZE, 0);szMessageret = 0;printf(Received %d bytes: %sn, ret, szMessage);/ Clean upclosesocket(sClient);WSACleanup();return 0;这是一个最简单的客户端代码，负责发送数据，然后接受返回。 二、使用select模型的服务器 C+代码 /writebylarry /2009-8-20 /Thisisserverusingselectmodel. #includestdafx.h #include #include #definePORT5150 #defineMSGSIZE1024 #pragmacomment(lib,ws2_32.lib) intg_iTotalConn=0; SOCKETg_CliSocketArrFD_SETSIZE; DWORDWINAPIWorkerThread(LPVOIDlpParam); intmain(intargc,char*argv) WSADATAwsaData; SOCKETsListen,sClient; SOCKADDR_INlocal,client; intiAddrSize=sizeof(SOCKADDR_IN); DWORDdwThreadId; /Initializewindowssocketlibrary WSAStartup(0x0202,&wsaData); /Createlisteningsocket sListen=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP); /Bind local.sin_family=AF_INET; local.sin_addr.S_un.S_addr=htonl(INADDR_ANY); local.sin_port=htons(PORT); bind(sListen,(sockaddr*)&local,sizeof(SOCKADDR_IN); /Listen listen(sListen,3); /Createworkerthread CreateThread(NULL,0,WorkerThread,NULL,0,&dwThreadId); while(TRUE) /Acceptaconnection sClient=accept(sListen,(sockaddr*)&client,&iAddrSize); printf(Acceptedclient:%s:%dn,inet_ntoa(client.sin_addr),ntohs(client.sin_port); /Addsockettog_CliSocketArr g_CliSocketArrg_iTotalConn+=sClient; return0; DWORDWINAPIWorkerThread(LPVOIDlpParam) inti; fd_setfdread; intret; structtimevaltv=1,0; charszMessageMSGSIZE; while(TRUE) FD_ZERO(&fdread); for(i=0;ig_iTotalConn;i+) FD_SET(g_CliSocketArri,&fdread); /Weonlycarereadevent ret=select(0,&fdread,NULL,NULL,&tv); if(ret=0) /Timeexpired continue; for(i=0;ig_iTotalConn;i+) if(FD_ISSET(g_CliSocketArri,&fdread) /Areadeventhappenedong_CliSocketArr ret=recv(g_CliSocketArri,szMessage,MSGSIZE,0); if(ret=0|(ret=SOCKET_ERROR&WSAGetLastError()=WSAECONNRESET) /Clientsocketclosed printf(Clientsocket%dclosed.n,g_CliSocketArri); closesocket(g_CliSocketArri); if(ig_iTotalConn-1) g_CliSocketArri-=g_CliSocketArr-g_iTotalConn; else /Wereveivedamessagefromclient szMessageret=0; send(g_CliSocketArri,szMessage,strlen(szMessage),0); / write by larry/ 2009-8-20/ This is server using select model.#include stdafx.h#include #include #define PORT 5150#define MSGSIZE 1024#pragma comment(lib, ws2_32.lib)int g_iTotalConn = 0;SOCKET g_CliSocketArrFD_SETSIZE;DWORD WINAPI WorkerThread(LPVOID lpParam);int main(int argc, char* argv)WSADATA wsaData;SOCKET sListen, sClient;SOCKADDR_IN local, client;int iAddrSize = sizeof(SOCKADDR_IN);DWORD dwThreadId;/ Initialize windows socket libraryWSAStartup(0x0202, &wsaData);/ Create listening socketsListen = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);/ Bindlocal.sin_family = AF_INET;local.sin_addr.S_un.S_addr = htonl(INADDR_ANY);local.sin_port = htons(PORT);bind(sListen, (sockaddr*)&local, sizeof(SOCKADDR_IN);/ Listenlisten(sListen, 3);/ Create worker threadCreateThread(NULL, 0, WorkerThread, NULL, 0, &dwThreadId);while (TRUE) / Accept a connectionsClient = accept(sListen, (sockaddr*)&client, &iAddrSize);printf(Accepted client:%s:%dn, inet_ntoa(client.sin_addr), ntohs(client.sin_port);/ Add socket to g_CliSocketArrg_CliSocketArrg_iTotalConn+ = sClient;return 0;DWORD WINAPI WorkerThread(LPVOID lpParam)int i;fd_set fdread;int ret;struct timeval tv = 1, 0;char szMessageMSGSIZE;while (TRUE) FD_ZERO(&fdread);for (i = 0; i g_iTotalConn; i+) FD_SET(g_CliSocketArri, &fdread);/ We only care read eventret = select(0, &fdread, NULL, NULL, &tv);if (ret = 0) / Time expiredcontinue;for (i = 0; i g_iTotalConn; i+) if (FD_ISSET(g_CliSocketArri, &fdread) / A read event happened on g_CliSocketArrret = recv(g_CliSocketArri, szMessage, MSGSIZE, 0);if (ret = 0 | (ret = SOCKET_ERROR & WSAGetLastError() = WSAECONNRESET) / Client socket closedprintf(Client socket %d closed.n, g_CliSocketArri);closesocket(g_CliSocketArri);if (i g_iTotalConn-1) g_CliSocketArri- = g_CliSocketArr-g_iTotalConn; else / We reveived a message from clientszMessageret = 0;send(g_CliSocketArri, szMessage, strlen(szMessage), 0);这是异步模型中最简单的一种，服务器端的几个主要流程如下： 1.创建监听套接字，绑定，监听； 2.创建工作者线程； 3.创建一个套接字数组，用来存放当前所有活动的客户端套接字，每accept一个连接就更新一次数组； 4.接受客户端的连接。Socket I/O模型之异步选择(WSAAsyncSelect)使用异步选择模型，应用程序可在一个套接字上，接收以Windows消息为基础的网络事件通知。具体的做法是在建好一个套接字后，调用WSAAsyncSelect函数。 服务器端代码： C+代码 /writebylarry /2009-8-20 /ThisisaserverusingWSAAsyncSelectmodel. #includestdafx.h #include #include #definePORT5150 #defineMSGSIZE1024 #defineWM_SOCKETWM_USER+0 #pragmacomment(lib,ws2_32.lib) LRESULTCALLBACKWndProc(HWND,UINT,WPARAM,LPARAM); intAPIENTRYWinMain(HINSTANCEhInstance,HINSTANCEhPrevInstance,LPSTRlpCmdLine,intnCmdShow) staticTCHARszAppName=_T(AsyncSelectModel); HWNDhwnd; MSGmsg; WNDCLASSwndclass; wndclass.style=CS_HREDRAW|CS_VREDRAW; wndclass.lpfnWndProc=WndProc; wndclass.cbClsExtra=0; wndclass.cbWndExtra=0; wndclass.hInstance=hInstance; wndclass.hIcon=LoadIcon(NULL,IDI_APPLICATION); wndclass.hCursor=LoadCursor(NULL,IDC_ARROW); wndclass.hbrBackground=(HBRUSH)GetStockObject(WHITE_BRUSH); wndclass.lpszMenuName=NULL; wndclass.lpszClassName=szAppName; if(!RegisterClass(&wndclass) MessageBox(NULL,_T(ThisprogramrequiresWindowsNT!),szAppName,MB_ICONERROR); return0; hwnd=CreateWindow(szAppName,/windowclassname _T(AsyncSelectModel),/windowcaption WS_OVERLAPPEDWINDOW,/windowstype CW_USEDEFAULT,/initialxpostion CW_USEDEFAULT,/initialypostion CW_USEDEFAULT,/initialxsize CW_USEDEFAULT,/initialysize NULL,/parentwindowhandle NULL,/windowmenuhandle hInstance,/programinstancehandle NULL);/creationparameters ShowWindow(hwnd,nCmdShow); UpdateWindow(hwnd); while(GetMessage(&msg,NULL,0,0) TranslateMessage(&msg); DispatchMessage(&msg); returnmsg.wParam; LRESULTCALLBACKWndProc(HWNDhwnd,UINTmessage,WPARAMwParam,LPARAMlParam) WSADATAwsaData; staticSOCKETsListen; SOCKETsClient; SOCKADDR_INlocal,client; intret,iAddrSize=sizeof(client); charszMessageMSGSIZE; switch(message) caseWM_CREATE: /Initializewindowssocketlibrary WSAStartup(0x0202,&wsaData); /Createlisteningsocket sListen=socket(AF_INET,SOCK_STREAM,IPPROTO_TCP); /Bind local.sin_family=AF_INET; local.sin_addr.S_un.S_addr=htonl(INADDR_ANY); local.sin_port=htons(PORT); bind(sListen,(sockaddr*)&local,sizeof(SOCKADDR_IN); /Listen listen(sListen,3); /AssociatelisteningsocketwithFD_ACCEPTevent WSAAsyncSelect(sListen,hwnd,WM_SOCKET,FD_ACCEPT); return0; caseWM_DESTROY: closesocket(sListen); WSACleanup(); PostQuitMessage(0); return0; caseWM_SOCKET: if(WSAGETSELECTERROR(lParam) closesocket(wParam); break; switch(WSAGETSELECTEVENT(lParam) caseFD_ACCEPT: /Acceptaconnectionfromclient sClient=accept(wParam,(sockaddr*)&client,&iAddrSize); /AssociateclientsocketwithFD_READandFD_CLOSEevent WSAAsyncSelect(sClient,hwnd,WM_SOCKET,FD_READ|FD_CLOSE); break; caseFD_READ: ret=recv(wParam,szMessage,MSGSIZE,0); if(ret=0|(ret=SOCKET_ERROR&WSAGetLastError()=WSAECONNRESET) closesocket(wParam); else szMessageret=0; send(wParam,szMessage,strlen(szMessage),0); break; caseFD_CLOSE: closesocket(wParam); break; return0; returnDefWindowProc(hwnd,message,wParam,lParam); / write by larry/ 2009-8-20/ This is a server using WSAAsyncSelect model.#include stdafx.h#include #include #define PORT 5150#define MSGSIZE 1024#define WM_SOCKET WM_USER+0#pragma comment(lib, ws2_32.lib)LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);int APIENTRY WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow) static TCHAR szAppName = _T(AsyncSelect Model);HWND hwnd;MSG msg;WNDCLASS wndclass;wndclass.style = CS_HREDRAW | CS_VREDRAW;wndclass.lpfnWndProc = WndProc;wndclass.cbClsExtra = 0;wndclass.cbWndExtra = 0;wndclass.hInstance = hInstance;wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);wndclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);wndclass.lpszMenuName = NULL;wndclass.lpszClassName = szAppName;if (!RegisterClass(&wndclass)MessageBox(NULL, _T(This program requires Windows NT!), szAppName, MB_ICONERROR);return 0;hwnd = CreateWindow(szAppName, / window class name_T(AsyncSelect Model), / window captionWS_OVERLAPPEDWINDOW, / window stypeCW_USEDEFAULT, / initial x postionCW_USEDEFAULT, / initial y postionCW_USEDEFAULT, / initial x sizeCW_USEDEFAULT, / initial y sizeNULL, / parent window handleNULL, / window menu handlehInstance, / program instance handleNULL); / creation parametersShowWindow(hwnd, nCmdShow);UpdateWindow(hwnd);while (GetMessage(&msg, NULL, 0, 0)TranslateMessage(&msg);DispatchMessage(&msg);return msg.wParam;LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)WSADATA wsaData;static SOCKET sListen;SOCKET sClient;SOCKADDR_IN local, client;int ret, iAddrSize = sizeof(client);char szMessageMSGSIZE;switch (message)case WM_CREATE:/ Initialize windows socket libraryWSAStartup(0x0202, &wsaData);/ Create listening socketsListen = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP);/ Bindlocal.sin_family = AF_INET;local.sin_addr.S_un.S_addr = htonl(INADDR_ANY);local.sin_port = htons(PORT);bind(sListen, (sockaddr*)&local, sizeof(SOCKADDR_IN);/ Listenlisten(sListen, 3);/ Associate listening socket with FD_ACCEPT eventWSAAsyncSelect(sListen, hwnd, WM_SOCKET, FD_ACCEPT);return 0;case WM_DESTROY:closesocket(sListen);WSACleanup();PostQuitMessage(0);return 0;case WM_SOCKET:if (WSAGETSELECTERROR(lParam)closesocket(wParam);break;switch (WSAGETSELECTEVENT(lParam)case FD_ACCEPT:/ Accept a connection from clientsClient = accept(wParam, (sockaddr*)&client, &iAddrSize);/ Associate client socket with FD_READ and FD_CLOSE eventWSAAsyncSelect(sClient, hwnd, WM_SOCKET, FD_READ | FD_CLOSE);break;case FD_READ:ret = recv(wParam, szMessage, MSGSIZE, 0);if (ret = 0 | (ret = SOCKET_ERROR & WSAGetLastError() = WSAECONNRESET)closesocket(wParam);elseszMessageret = 0;send(wParam, szMessage, strlen(szMessage), 0);break;case FD_CLOSE:closesocket(wParam);break;return 0;return DefWindowProc(hwnd, message, wParam, lParam);服务器端得主要流程： 1.在WM_CREATE消息处理函数中，初始化Windows Socket library，创建监听套接字，绑定，监听，并且调用WSAAsyncSelect函数表示我们关心在监听套接字上发生的FD_ACCEPT事件； 2.自定义一个消息WM_SOCKET，一旦在我们所关心的套接字（监听套接字和客户端套接字）上发生了某个事件，系统就会调用WndProc并且message参数被设置为WM_SOCKET； 3.在WM_SOCKET的消息处理函数中，分别对FD_ACCEPT、FD_READ和FD_CLOSE事件进行处理； 4.在窗口销毁消息(WM_DESTROY)的处理函数中，我们关闭监听套接字，清除Windows Socket library WSAAsyncSelect函数的网络事件类型可以有以下一种： FD_READ 应用程序想要接收有关是否可读的通知，以便读入数据 FD_WRITE 应用程序想要接收有关是否可写的通知，以便写入数据 FD_OOB 应用程序想接收是否有带外（OOB）数据抵达的通知 FD_ACCEPT 应用程序想接收与进入连接有关的通知 FD_CONNECT 应用程序想接收与一次连接或者多点join操作完成的通知 FD_CLOSE 应用程序想接收与套接字关闭有关的通知 FD_QOS 应用程序想接收套接字“服务质量”（QoS）发生更改的通知 FD_GROUP_QOS 应用程序想接收套接字组“服务质量”发生更改的通知（现在没什么用处，为未来套接字组的使用保留） FD_ROUTING_INTERFACE_CHANGE 应用程序想接收在指定的方向上，与路由接口发生变化的通知 FD_ADDRESS_LIST_CHANGE 应用程序想接收针对套接字的协议家族，本地地址列表发生变化的通知 Socket I/O模型之事件选择(WSAEventSelect)WSAEventSelect和WSAAsyncSelect模型类似，它也允许应用程序在一个或多个套接字上，接收以事件为基础的网络事件通知。对于WSAAsyncSelect模型采用的网络事件来说，它们均可原封不动地移植到事件选择模型上。在用事件选择模型开发的应用程序中，也能接收和处理所有那些事件。该模型最主要的差别在于网络事件会投递至一个事件对象句柄，而非投递至一个窗口例程。 服务器端代码： C+代码 /writebylarry /2009-8-20 /ThisisaserverusingWSAEventSelectmodel. #includestdafx.h #include #include #pragmacomment(lib,ws2_32.lib) #definePORT5150 #defineMSGSIZE1024 intg_iTotalConn=0; SOCKETg_CliSocketArrMAXIMUM_WAIT_OBJECTS; WSAEVENTg_CliEventArrMAXIMUM_WAIT_OBJECTS; DWORDWINAPIWorkerThread(LPVOIDlpParam); voidCleanup(intindex); intmain(intargc,char