Winsock异步方式编程实例 原创

//这是一个winsock异步编程的例子
//这个服务监听1000端口,可以使用 telnet localhost 1000进行测试,最大允许20个连接
#include
#include
#pragma comment(lib, "WS2_32.LIB")
#define MAX_SOCKETS 20
#define MAX_BACKLOG 1
#define PORT 1000

SOCKET Startlisten(int port)
{
   
    WORD wVersion=MAKEWORD(2,0);
    WSADATA wsData;
    int nResult= WSAStartup(wVersion,&wsData);
    if(nResult !=0)
    {
        return 0;
    }
    SOCKET sock=socket(AF_INET,SOCK_STREAM,IPPROTO_IP);
    if(sock==INVALID_SOCKET)
    {
        return 0;
    }
    sockaddr_in addr;
    addr.sin_family=AF_INET;
    addr.sin_port= htons(port); //保证字节顺序
    addr.sin_addr.s_addr= htonl(INADDR_ANY);
    nResult=bind(sock,(sockaddr*)&addr,sizeof(sockaddr));
    if(nResult==SOCKET_ERROR)
    {
        return 0;
    }
    nResult=listen(sock,MAX_BACKLOG); //最多 MAX_BACKLOG 个 Pending 连接
    if(nResult==SOCKET_ERROR)
    {
        return 0;
    }
    printf("Please try: telnet localhost 1000/n");
    return sock;
}
int main()
{
    //init winsock env
    WORD wVersion=MAKEWORD(2,0);
    WSADATA wsData;
    int nResult= WSAStartup(wVersion,&wsData);

    //create the first event
    WSAEVENT eventList[MAX_SOCKETS+1];
    int eventIndex=0;
    eventList[eventIndex]=WSACreateEvent();

    //start listen on 1000
    SOCKET sockList[MAX_SOCKETS+1];
    sockList[eventIndex]=Startlisten(PORT);

    //use WSAEventSelect to set the server to running on async mode
    int rc = WSAEventSelect(sockList[eventIndex], eventList[eventIndex], FD_READ|FD_WRITE|FD_ACCEPT|FD_CLOSE|FD_CONNECT);
    int index;
    sockaddr_in client;
    //waiting on the events to deal with connect requests or network read event
    while( (index=WSAWaitForMultipleEvents(eventIndex+1,eventList,false,WSA_INFINITE,true)) != WSA_WAIT_FAILED)
    {
        index -= WSA_WAIT_EVENT_0;
        WSANETWORKEVENTS type;
        WSAEnumNetworkEvents(sockList[index],eventList[index],&type);
        switch(type.lNetworkEvents)
        {
            case  FD_ACCEPT:
                {
                    int len=sizeof(sockaddr);
                    if (eventIndex < MAX_SOCKETS)
                    {
                        ++eventIndex;
                        sockList[eventIndex] =accept(sockList[index],(sockaddr*)&client,&len);
                        eventList[eventIndex]=WSACreateEvent();
                        rc = WSAEventSelect(sockList[eventIndex], eventList[eventIndex], FD_READ|FD_WRITE|FD_CLOSE|FD_CONNECT);
                        printf("connected from %s:%d/n",inet_ntoa( client.sin_addr ),client.sin_port);
                    }
                }
                break;
            case FD_READ:
                {
                    char mess;
                    rc =recv(sockList[index],&mess,1,0);
   
                    //ctrl+c == 3
                    if (mess == 3 || rc ==SOCKET_ERROR)
                    {
                        shutdown(sockList[index],SD_SEND);
                        break;
                    }

                    rc=send(sockList[index],&mess,sizeof(mess),0);
                    printf("%c",mess);

                }
                break;
            case FD_WRITE:
                {
                    char buf[256];
                    sprintf(buf,"hello,you are the %d client./n",eventIndex);
                    rc=send(sockList[index],buf,strlen(buf),0);
                }
                break;
            case FD_CLOSE:
                {
                    int len=sizeof(sockaddr);
                    getpeername(sockList[index],(sockaddr*)&client,&len);
                    printf("Closed from %s:%d/n",inet_ntoa( client.sin_addr ),client.sin_port);
                    closesocket(sockList[index]);
                }
                break;
        }
    }


    return 0;
}