c - 我如何使用此客户端程序访问 tomcat 资源？

Question

我可以从我的浏览器使用以下 URL 从 tomcat 服务器访问资源，

http://localhost:8080/test/file1.xml

请求头:

Status Code:200 OK
Request Headersview parsed
GET /test/file1.xml HTTP/1.1
Host: localhost:8080
Connection: keep-alive
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/34.0.1847.131 Safari/537.36
Accept-Encoding: gzip,deflate,sdch
Accept-Language: en-US,en;q=0.8
Response Headersview parsed

响应头:

HTTP/1.1 200 OK
Server: Apache-Coyote/1.1
Accept-Ranges: bytes
ETag: W/"9-1399430961358"
Last-Modified: Wed, 07 May 2014 02:49:21 GMT
Content-Type: application/xml
Content-Length: 9
Date: Fri, 16 May 2014 16:37:10 GMT

但是我无法使用下面的windows客户端程序访问相同的资源，你能告诉我原因吗？

#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 65536


int __cdecl main(int argc, char **argv) 
{
    WSADATA wsaData;
    SOCKET ConnectSocket = INVALID_SOCKET;
    struct addrinfo *result = NULL,
                    *ptr = NULL,
                    hints;
    char *sendbuf = "GET /test/file1.xml HTTP/1.1";
    char recvbuf[DEFAULT_BUFLEN];
    int iResult;
    int recvbuflen = DEFAULT_BUFLEN;


    // 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_UNSPEC;
    hints.ai_socktype = SOCK_STREAM;
    hints.ai_protocol = IPPROTO_TCP;

    // Resolve the server address and port
    iResult = getaddrinfo("127.0.0.1", "8080", &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);
        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);
        if (iResult == SOCKET_ERROR) {
            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
    iResult = send( ConnectSocket, sendbuf, (int)strlen(sendbuf), 0 );
    if (iResult == SOCKET_ERROR) {
        printf("send failed with error: %d\n", WSAGetLastError());
        closesocket(ConnectSocket);
        WSACleanup();
        return 1;
    }

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


    // Receive until the peer closes the connection
    do {

        iResult = recv(ConnectSocket, recvbuf, recvbuflen-1, 0);
        if ( iResult > 0 ){
            recvbuf[iResult]='\0';
            printf("Bytes received: %d, httpresponse: %s\n", iResult,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;
}

输出是:

c:\code>client.exe
Bytes Sent: 28
Connection closed

Answer 1

这应该有效。

发送 HTTP/1.0 请求，

char *sendbuf = "GET /test/file1.xml HTTP/1.0\r\n\r\n "; 

发送http 1.1请求，

char *sendbuf = "GET /test/file1.xml HTTP/1.1\r\nHost: localhost\r\n\r\n ";

虚拟主机的概念允许在一个系统或网络服务器上有多个网站。 HTTP/1.1 服务器支持所谓的虚拟主机。因此，在 HTTP/1.1 GET 请求中，必须包含一个名为“Host”的请求 header ，以选择其中一个虚拟主机。