MSG_OOB winsock

版权声明： https://blog.csdn.net/dashoumeixi/article/details/85184797

win下没有unix中的信号, MSG_OOB的解决方式是 使用select 中的异常套接字: exceptfds

关于oob 的解释都在另一篇文章中了.这里不再解释, 仅仅是windows实现

oob_recv.c

// oob_recv.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include <stdlib.h>
#include <winsock2.h>
#include <Windows.h>
#pragma comment(lib, "ws2_32.lib")

#define BUFFSIZE 8192
int _tmain(int argc, char* argv[])
{
    WSADATA wsadata;

    int err = 0;
    if ((err =WSAStartup(MAKEWORD(2, 2), &wsadata) )!= 0){
        printf("startup error : %d\n", err);
        return 0;
    }

    SOCKADDR_IN serv_addr, client_addr;
    memset(&serv_addr, 0, sizeof(serv_addr));
    memset(&client_addr, 0, sizeof(client_addr));
    serv_addr.sin_addr.s_addr = INADDR_ANY;
    serv_addr.sin_port = htons(9988);
    serv_addr.sin_family = AF_INET;

    SOCKET hListenSocket = socket(AF_INET, SOCK_STREAM, 0);

    if (bind(hListenSocket, (SOCKADDR*)&serv_addr, sizeof(serv_addr)) == SOCKET_ERROR)
    {
        _tprintf(TEXT("bind error :%d\n"), WSAGetLastError());
        closesocket(hListenSocket);
        WSACleanup();
        return 0;
    }

    if (SOCKET_ERROR == listen(hListenSocket, 10)){
        _tprintf(TEXT("listen error :%d\n"), WSAGetLastError());
        closesocket(hListenSocket);
        WSACleanup();
    }

    int client_len = sizeof(client_addr);
    SOCKET hRecvSocket = accept(hListenSocket, (SOCKADDR*)&client_addr,&client_len);
    printf("ip:%s\n",inet_ntoa(client_addr.sin_addr));
    fd_set read_set, except_set,rset,eset;
    FD_ZERO(&read_set);
    FD_ZERO(&except_set);
    FD_SET(hRecvSocket, &read_set);
    FD_SET(hRecvSocket, &except_set);
    struct timeval timeout;
    timeout.tv_sec = 5;
    timeout.tv_usec = 0;
    int n = 0 , strlen = 0;
    char buf[BUFFSIZE];
    while (1)
    {
        rset = read_set;
        eset = except_set;
        n = select(0,&rset,NULL,&eset,&timeout);
        if (0 == n){
            puts("timeout~");
            continue;
        }
        else if (SOCKET_ERROR == n){
            printf("error : %d\n", WSAGetLastError());
            continue;
        }
        else {
            //OOB 数据
            if (FD_ISSET(hRecvSocket, &eset)){
                 strlen = recv(hRecvSocket, buf, BUFFSIZE - 1, MSG_OOB);
                 if (0 == strlen){
                     puts("on recv oob data , peer closed");
                     closesocket(hRecvSocket);
                     break;
                 }
                 printf("oob data len :%d\n", strlen);
                 buf[strlen] = 0;
                 printf("oob data buf :%s\n", buf);
            }

            //普通数据
            if (FD_ISSET(hRecvSocket, &rset)){
                strlen = recv(hRecvSocket, buf, BUFFSIZE - 1, 0);
                if (0 == strlen){
                    puts("on recv nornal data , peer closed");
                    closesocket(hRecvSocket);
                    break;
                }
                buf[strlen] = 0;
                printf("normal data : %s\n", buf);
            }
        }
    }
    


    closesocket(hListenSocket);
    WSACleanup();
    return 0;
}

oob_send.c

// sock.cpp : Defines the entry point for the console application.
//

#include "stdafx.h"
#include <stdlib.h>
#include <winsock2.h>
#include <Windows.h>
#pragma comment(lib, "ws2_32.lib")


int _tmain(int argc, char* argv[])
{

    WSADATA wsadata;
    int err = 0;
    if ((err = WSAStartup(MAKEWORD(2, 2), &wsadata)) != 0){
        printf("startup error:%d\n", err);
        return 0;
    }
    SOCKET hSock = socket(AF_INET, SOCK_STREAM, 0);
    SOCKADDR_IN send_addr;
    memset(&send_addr, 0, sizeof(send_addr));
    send_addr.sin_family = AF_INET;
    send_addr.sin_addr.s_addr = inet_addr("127.0.0.1");
    send_addr.sin_port = htons(9988);

    if (SOCKET_ERROR == connect(hSock, (SOCKADDR*)&send_addr, sizeof(send_addr))){
        _tprintf(TEXT("connect error , errno:%ld\n"),WSAGetLastError());
        closesocket(hSock);
        WSACleanup();
        return 0;
    }
    puts("connect success");
    char buf1[] = "data1", buf2[] = "data2";
    char oob_buf1[] = "oob_data1", oob_buf2[] = "oob_data2";

    send(hSock, buf1, strlen(buf1), 0);

    //oob
    send(hSock, oob_buf1, strlen(oob_buf1), MSG_OOB);

    send(hSock, buf2, strlen(buf2), 0);

    //oob
    send(hSock, oob_buf2, strlen(oob_buf2), MSG_OOB);
    closesocket(hSock);

    WSACleanup(); 
    return 0;
}