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C++ Winsock Basic HTTP Connection

I had some unix socket code that I was working with, and I needed to convert it to run on windows. Thanks to a handy Windows Socket PDF, I was able to get some basic code going.

This is not meant to be 'production' level stuff... merely a hello world of using winsock. One of the things I did not account for in this code was download lag. For instance, if you are downloading a 40kb page it may take a few seconds. What happens is the recv() function can only access data that has already been downloaded, so this code will end an http download 'early' if the download is anything slower than instant.

#include <iostream>

#include <string>

#include <stdlib.h>

#include <winsock.h>//dont forget to add wsock32.lib to linker dependencies

using namespace std;

#define BUFFERSIZE 1024

void die_with_error(char *errorMessage);

void die_with_wserror(char *errorMessage);

int main(int argc, char *argv[])

{

    string request;

    string response;

    int resp_leng;

    char buffer[BUFFERSIZE];

    struct sockaddr_in serveraddr;

    int sock;

    WSADATA wsaData;

    char *ipaddress = "208.109.181.178";

    int port = 80;

    request+="GET /test.html HTTP/1.0\r\n";

    request+="Host: www.zedwood.com\r\n";

    request+="\r\n";

    //init winsock

    if (WSAStartup(MAKEWORD(2, 0), &wsaData) != 0)

        die_with_wserror("WSAStartup() failed");

    //open socket

    if ((sock = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP)) < 0)

        die_with_wserror("socket() failed");

    //connect

    memset(&serveraddr, 0, sizeof(serveraddr));

    serveraddr.sin_family      = AF_INET;

    serveraddr.sin_addr.s_addr = inet_addr(ipaddress);

    serveraddr.sin_port        = htons((unsigned short) port);

    if (connect(sock, (struct sockaddr *) &serveraddr, sizeof(serveraddr)) < 0)

        die_with_wserror("connect() failed");

    //send request

    if (send(sock, request.c_str(), request.length(), 0) != request.length())

        die_with_wserror("send() sent a different number of bytes than expected");

    //get response

    response = "";

    resp_leng= BUFFERSIZE;

    while (resp_leng == BUFFERSIZE)

    {

        resp_leng= recv(sock, (char*)&buffer, BUFFERSIZE, 0);

        if (resp_leng>0)

            response+= string(buffer).substr(0,resp_leng);

        //note: download lag is not handled in this code

    }

    //display response

    cout << response << endl;

    //disconnect

    closesocket(sock);

    //cleanup

    WSACleanup();

    return 0;

}

void die_with_error(char *errorMessage)

{

    cerr << errorMessage << endl;

    exit(1);

}

void die_with_wserror(char *errorMessage)

{

    cerr << errorMessage << ": " << WSAGetLastError() << endl;

    exit(1);

}