우울한하루

윤성우의 TCP/IP 에코 채팅 서버에서

다른사람들에게 채팅 내용이 전송되도록 수정한 소스이다.

#include 
#include 
#include 
#include 
#include 
#include 
#include 


#pragma comment(lib, "ws2_32.lib")

#define BUF_SIZE 100
#define READ 3
#define WRITE 5

int const NAME_SIZE = 10;

typedef struct          // socket intfo

{
    SOCKET hClntSock;
    SOCKADDR_IN clntAdr;
}PER_HANDLE_DATA, *LPPER_HANDLE_DATA;

typedef struct // buffer info
{
    OVERLAPPED overlapped;
    WSABUF wsaBuf;
    char buffer[BUF_SIZE];
    int rwMode;             // READ or WRITE
    
}PER_IO_DATA, *LPPER_IO_DATA;

typedef struct
{
    char id[NAME_SIZE];
    unsigned int level;
    
}USER_INFO, *PUSER_INFO;        // 나중에 PER_HANDLE_DATA 상속하자

std::list UserList; // 다른사람에게 채팅 전달해야하므로 user list 추가

DWORD WINAPI EchoThreadMain(LPVOID CompletionPortIO);

CRITICAL_SECTION cs;        // UserList 동기화를 위한 Critical Section


int main()
{
    WSADATA wsaData;
    HANDLE hComPort;
    SYSTEM_INFO sysInfo;
    LPPER_IO_DATA ioInfo;
    LPPER_HANDLE_DATA handleInfo;

    SOCKET hServSock;
    SOCKADDR_IN servAdr;
    int recvBytes, i, flags = 0;

    if (0 != WSAStartup(MAKEWORD(2, 2), &wsaData))
    {
        printf("WSAStartup() error!");
        exit(1);
    }

    hComPort = CreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL, 0, 0);
    GetSystemInfo(&sysInfo);

    for (i = 0; i < (int)sysInfo.dwNumberOfProcessors; ++i)
    {
        // Thread 핸들 정리 추가할 것
        _beginthreadex(NULL, 0, (_beginthreadex_proc_type)EchoThreadMain, (LPVOID)hComPort, 0, NULL);
    }

    hServSock = WSASocketW(AF_INET, SOCK_STREAM, 0, NULL, 0, WSA_FLAG_OVERLAPPED);
    memset(&servAdr, 0, sizeof(servAdr));
    servAdr.sin_family = AF_INET;
    inet_pton(AF_INET, "127.0.0.1", &(servAdr.sin_addr));
    servAdr.sin_port = htons(atoi("7777"));

    bind(hServSock, (SOCKADDR*)&servAdr, sizeof(servAdr));
    listen(hServSock, 5);

    InitializeCriticalSection(&cs);

    while (1)
    {
        SOCKET hClntSock;
        SOCKADDR_IN clntAdr;
        int addrLen = sizeof(clntAdr);

        hClntSock = accept(hServSock, (SOCKADDR*)&clntAdr, &addrLen);
        
        handleInfo = (LPPER_HANDLE_DATA)malloc(sizeof(PER_HANDLE_DATA));        // 누군가 접속할 때 마다 소켓 정보를 생성하고
        handleInfo->hClntSock = hClntSock;                                      // hClntSock은 지역변수이므로 저장한다
        memcpy(&(handleInfo->clntAdr), &clntAdr, addrLen);

        EnterCriticalSection(&cs);
        UserList.push_back(handleInfo);
        LeaveCriticalSection(&cs);

        CreateIoCompletionPort((HANDLE)hClntSock, hComPort, (DWORD)handleInfo, 0);  // 접속한 클라 소켓을 IOCP에 등록함

        ioInfo = (LPPER_IO_DATA)malloc(sizeof(PER_IO_DATA));                        // 신규 유저 접속 시 overlapped도 생성한다.
        memset(&(ioInfo->overlapped), 0, sizeof(OVERLAPPED));                       // 그리고 WSARecv 함수로 소켓 io완료 시 반환되는 wasBuf, overlapped 주소를 등록한다
        ioInfo->wsaBuf.len = BUF_SIZE;
        ioInfo->wsaBuf.buf = ioInfo->buffer;
        ioInfo->rwMode = READ;

        WSARecv(handleInfo->hClntSock, &(ioInfo->wsaBuf), 1, (LPDWORD)&recvBytes, (LPDWORD)&flags, &(ioInfo->overlapped), NULL);    // recv가 완료되었을 때 GetQueue...에서 반환됨
    }   

    DeleteCriticalSection(&cs);

    return 0;
}

DWORD WINAPI EchoThreadMain(LPVOID pComPort)
{
    HANDLE hComPort = (HANDLE)pComPort;
    SOCKET sock;
    DWORD bytesTrans;
    LPPER_HANDLE_DATA   handleInfo;
    LPPER_IO_DATA       ioInfo;
    DWORD flags = 0;
    char msg[BUF_SIZE];

    while (1)
    {
        GetQueuedCompletionStatus(hComPort, &bytesTrans, (LPDWORD)&handleInfo, (LPOVERLAPPED*)&ioInfo, INFINITE);
        sock = handleInfo->hClntSock;

        if (READ == ioInfo->rwMode)
        {
            puts("message received!");

            if (0 == bytesTrans)
            {
                EnterCriticalSection(&cs);
                std::list::iterator iter;
                for (iter = UserList.begin(); iter != UserList.end(); ++iter)
                {
                    if (sock == (*iter)->hClntSock)
                    {
                        UserList.erase(iter);
                        break;
                    }
                }
                LeaveCriticalSection(&cs);

                closesocket(sock);
                free(handleInfo);
                free(ioInfo);
                continue;
            }

            memset(msg, 0, BUF_SIZE);
            memcpy(msg, ioInfo->buffer, BUF_SIZE);
            free(ioInfo);
            
            EnterCriticalSection(&cs);                      // UserList는 여러 스레드가 접근하는 공유자원이므로 접근 시 cs 필수 
            std::list::iterator iter;
            for (iter = UserList.begin(); iter != UserList.end(); ++iter)  
            {
                // 소켓마다 overlapped를 새로 만들어야 한다. 왜냐하면 하나의 overlapped를 여러 소켓이 쓸 수 없기 때문이다. 
                ioInfo = (LPPER_IO_DATA)malloc(sizeof(PER_IO_DATA));
                memset(&(ioInfo->overlapped), 0, sizeof(OVERLAPPED));
                ioInfo->wsaBuf.buf = msg;                   // msg는 스레드마다 가지고 있는 지역변수이므로 공유자원이 아니므로 cs 사용을 하지 않는다
                ioInfo->wsaBuf.len = bytesTrans;
                ioInfo->rwMode = WRITE;
                WSASend((*iter)->hClntSock, &(ioInfo->wsaBuf), 1, NULL, 0, &(ioInfo->overlapped), NULL);
            }
            LeaveCriticalSection(&cs);

            ioInfo = (LPPER_IO_DATA)malloc(sizeof(PER_IO_DATA));
            memset(&(ioInfo->overlapped), 0, sizeof(OVERLAPPED));
            ioInfo->wsaBuf.len = BUF_SIZE;
            ioInfo->wsaBuf.buf = ioInfo->buffer;
            ioInfo->rwMode = READ;
            WSARecv(sock, &(ioInfo->wsaBuf), 1, NULL, &flags, &(ioInfo->overlapped), NULL);
        }
        else
        {
            puts("message sent!");
            free(ioInfo);
        }
    }
    
    return 0;
}