如何从 vc++ 查询 http 请求项目

Question

我正在编写一个示例程序以从某个站点获取文件。 但它回复我文件未找到错误，我不知道如何制作 http 标头。 任何人都可以帮我写http头。

我正在尝试以这种方式打印 ip(printf("%s\n",ptr->ai_addr->sa_data);) 但不知道如何打印IP地址??，我这样做对吗??

我的代码是：-

#define WIN32_LEAN_AND_MEAN

#include <windows.h>
#include <winsock2.h>
#include <ws2tcpip.h>
#include <stdlib.h>
#include <stdio.h>


#define WIN32_LEAN_AND_MEAN

#include <windows.h>
#include <winsock2.h>
#include <ws2tcpip.h>
#include <stdlib.h>
#include <stdio.h>


// Need to link with Ws2_32.lib, Mswsock.lib, and Advapi32.lib
#pragma comment (lib, "Ws2_32.lib")
#pragma comment (lib, "Mswsock.lib")
#pragma comment (lib, "AdvApi32.lib")


#define DEFAULT_BUFLEN 512
#define DEFAULT_PORT "80"

int __cdecl main(int argc, char **argv) 
{
    WSADATA wsaData;
    SOCKET ConnectSocket = INVALID_SOCKET;
    struct addrinfo *result = NULL,
                    *ptr = NULL,
                    hints;
    char *sendbuf = "GET / HTTP/1.1[CRLF] Host: www.espncricinfo.com[CRLF]Connection: close[CRLF]User-Agent: Web-sniffer/1.0.37 (+http://web-sniffer.net/)[CRLF]Accept-Encoding: gzip[CRLF]Accept-Charset: ISO-8859-1,UTF-8;q=0.7,*;q=0.7[CRLF]Cache-Control: no-cache[CRLF]Accept-Language: de,en;q=0.7,en-us;q=0.3 \r\n";
    char buff[DEFAULT_BUFLEN],recvbuf[512]; 
    int iResult;
    int recvbuflen = DEFAULT_BUFLEN;

    // Validate the parameters
    if (argc != 1) {
        printf("usage: %s server-name\n", argv[0]);
        return 1;
    }

    // Initialize Winsock
    iResult = WSAStartup(MAKEWORD(2,2), &wsaData);
    if (iResult != 0) {
        printf("WSAStartup failed with error: %d\n", iResult);
        return 1;
    }

    ZeroMemory( &hints, sizeof(hints) );
    hints.ai_family = AF_INET;
    hints.ai_socktype = SOCK_STREAM;
    hints.ai_protocol = IPPROTO_TCP;
    // Resolve the server address and port
    iResult = getaddrinfo("122.169.255.9",DEFAULT_PORT, &hints, &result);
    if ( iResult != 0 ) {
        printf("getaddrinfo failed with error: %d\n", iResult);
        WSACleanup();
        return 1;
    }

    // Attempt to connect to an address until one succeeds
    for(ptr=result; ptr != NULL ;ptr=ptr->ai_next) {

        // Create a SOCKET for connecting to server

        ConnectSocket = socket(ptr->ai_family, ptr->ai_socktype, 
            ptr->ai_protocol);
        printf("inside loop %s ",ptr->ai_addr->sa_data);
        if (ConnectSocket == INVALID_SOCKET) {
            printf("socket failed with error: %ld\n", WSAGetLastError());
            WSACleanup();
            return 1;
        }

        // Connect to server.
        iResult = connect(ConnectSocket, ptr->ai_addr, (int)ptr->ai_addrlen);
        printf("%d\n",ptr->ai_addrlen);
//      printf("%s\n",ptr->ai_addr->sa_family);
        printf("%s\n",ptr->ai_addr->sa_data);

        if (iResult == SOCKET_ERROR) {
            printf("socket error\n");
            printf("failed with error: %d\n", WSAGetLastError());
            closesocket(ConnectSocket);
            ConnectSocket = INVALID_SOCKET;
            continue;
        }
        break;
    }

    freeaddrinfo(result);

    if (ConnectSocket == INVALID_SOCKET) {
        printf("Unable to connect to server!\n");
        WSACleanup();
        return 1;
    }
    // Send an initial buffer
    char filepath[]="pakistan/content/current/story/517271.html";
    sprintf(buff,"GET %s\r\n",filepath);
    iResult = send( ConnectSocket,buff, (int)strlen(buff), 0 );
    if (iResult == SOCKET_ERROR)
    {
        printf("send failed with error: %d\n", WSAGetLastError());
        closesocket(ConnectSocket);
        WSACleanup();
        return 1;
    }

    printf("Bytes Sent: %ld\n", iResult);

    // shutdown the connection since no more data will be sent
    iResult = shutdown(ConnectSocket, SD_SEND);
    if (iResult == SOCKET_ERROR) {
        printf("shutdown failed with error: %d\n", WSAGetLastError());
        closesocket(ConnectSocket);
        WSACleanup();
        return 1;
    } 

    do 
    {
        iResult = recv(ConnectSocket, recvbuf, recvbuflen, 0);
        //if ( iResult > 0 ) printf("Bytes received: %d\n", iResult);
         if ( iResult > 0 )
         {
            printf("Bytes received: %d\n", iResult);
            printf("%s",recvbuf);
         }
         else if ( iResult == 0 )
            printf("Connection closed\n");
        else
            printf("recv failed with error: %d\n", WSAGetLastError()); 

    } while( iResult>0 );

    // cleanup
    closesocket(ConnectSocket);
    WSACleanup();

    return 0;
}

Answer 1

如果您收到“找不到文件”的消息，那是因为您请求的文件无法找到。

也许可以尝试使用前导斜杠的 "/pakistan/content/current/story/517271.html"。

你的 HTTP 协议说明符在哪里？

写：

GET path HTTP/1.0

（1.0因为你可能不想搞乱虚拟主机；1.1如果你必须的话）

为什么你在尝试读取之前关闭套接字......？我知道你只关闭“发送”管道，但它仍然看起来很奇怪。

也许您应该使用预先建立的库来为您完成此操作。

---

http://122.169.255.9/ 上的网络服务器似乎并未实际工作。也许首先使用已知良好的服务器（例如 http://www.google.com）进行测试。

Answer 2

如果您要使用 Microsoft Windows 函数，WinInet 中的 HTTP 函数要容易得多。请参阅 HttpOpenRequest/HttpSendRequest/HttpQueryInfo/InternetReadFile

Answer 3

如果您不想重新发明轮子，请使用像 libcurl 这样的库。

Answer 4

除了 Tomalak Geret'kal 之外，

您还需要使用 HTTP/1.0，除非您想要检查分块内容以及 HTTP 1.1 可能向您抛出的更多内容。

安装 Wireshark 并记录请求。你就会看到出了什么问题。

我不知道 [CRLF] 被自动更改为 \r\n