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#include <iostream>
#include <winsock2.h>
#include <windows.h>
using namespace std;
const int REQ_WINSOCK_VER = 2; // Minimum winsock version required
const char DEF_SERVER_NAME[] = "www.yahoo.com";
const int SERVER_PORT = 80;
const int TEMP_BUFFER_SIZE = 128;
const char HEAD_REQUEST_PART1[] =
{
"HEAD / HTTP/1.1\r\n" // Get root index from server
"Host: " // Specify host name used
};
const char HEAD_REQUEST_PART2[] =
{
"\r\n" // End hostname header from part1
"User-agent: HeadReqSample\r\n" // Specify user agent
"Connection: close\r\n" // Close connection after response
"\r\n" // Empty line indicating end of request
};
// IP number typedef for IPv4
typedef unsigned long IPNumber;
bool RequestHeaders(const char* pServername);
class HRException
{
public:
HRException() :
m_pMessage("") {}
virtual ~HRException() {}
HRException(const char *pMessage) :
m_pMessage(pMessage) {}
const char * what() { return m_pMessage; }
private:
const char *m_pMessage;
};
int main()
{
int iRet = 1;
WSADATA wsaData;
cout << "Initializing winsock... ";
if (WSAStartup(MAKEWORD(REQ_WINSOCK_VER,0), &wsaData)==0)
{
// Check if major version is at least REQ_WINSOCK_VER
if (LOBYTE(wsaData.wVersion) >= REQ_WINSOCK_VER)
{
cout << "initialized.\n";
// Set default hostname:
const char* pHostname = DEF_SERVER_NAME;
iRet = !RequestHeaders(pHostname);
}
else
{
cerr << "required version not supported!";
}
cout << "Cleaning up winsock... ";
// Cleanup winsock
if (WSACleanup()!=0)
{
cerr << "cleanup failed!\n";
iRet = 1;
}
cout << "done.\n";
}
else
{
cerr << "startup failed!\n";
}
cout << WSAGetLastError();
return iRet;
}
IPNumber FindHostIP(const char *pServerName)
{
HOSTENT *pHostent;
// Get hostent structure for hostname:
if (!(pHostent = gethostbyname(pServerName)))
throw HRException("could not resolve hostname.");
// Extract primary IP address from hostent structure:
if (pHostent->h_addr_list && pHostent->h_addr_list[0])
return *reinterpret_cast<IPNumber*>(pHostent->h_addr_list[0]);
return 0;
}
void FillSockAddr(sockaddr_in *pSockAddr, const char *pServerName, int portNumber)
{
// Set family, port and find IP
pSockAddr->sin_family = AF_INET;
pSockAddr->sin_port = htons(portNumber);
pSockAddr->sin_addr.S_un.S_addr = FindHostIP(pServerName);
}
bool RequestHeaders(const char* pServername)
{
SOCKET hSocket = INVALID_SOCKET;
char tempBuffer[TEMP_BUFFER_SIZE];
sockaddr_in sockAddr = {0};
bool bSuccess = true;
try
{
// Lookup hostname and fill sockaddr_in structure:
cout << "Looking up hostname " << pServername << "... ";
FillSockAddr(&sockAddr, pServername, SERVER_PORT);
cout << "found.\n";
// Create socket
cout << "Creating socket... ";
if ((hSocket = socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)) == INVALID_SOCKET)
throw HRException("could not create socket.");
cout << "created.\n";
if (hSocket!=INVALID_SOCKET)
closesocket(hSocket);
// Connect to server
cout << "Attempting to connect to " << inet_ntoa(sockAddr.sin_addr)
<< ":" << SERVER_PORT << "... ";
if (connect(hSocket, reinterpret_cast<sockaddr*>(&sockAddr), sizeof(sockAddr))!=0)
throw HRException("could not connect.");
cout << "connected.\n";
cout << "Sending request... ";
// send request part 1
if (send(hSocket, HEAD_REQUEST_PART1, sizeof(HEAD_REQUEST_PART1)-1, 0)==SOCKET_ERROR)
throw HRException("failed to send data.");
// send hostname
if (send(hSocket, pServername, lstrlen(pServername), 0)==SOCKET_ERROR)
throw HRException("failed to send data.");
// send request part 2
if (send(hSocket, HEAD_REQUEST_PART2, sizeof(HEAD_REQUEST_PART2)-1, 0)==SOCKET_ERROR)
throw HRException("failed to send data.");
cout << "request sent.\n";
cout << "Dumping received data...\n\n";
// Loop to print all data
while(true)
{
int retval;
retval = recv(hSocket, tempBuffer, sizeof(tempBuffer)-1, 0);
if (retval==0)
{
break; // Connection has been closed
}
else if (retval==SOCKET_ERROR)
{
throw HRException("socket error while receiving.");
}
else
{
// retval is number of bytes read
// Terminate buffer with zero and print as string
tempBuffer[retval] = 0;
cout << tempBuffer;
}
}
}
catch(HRException e)
{
cerr << "\nError: " << e.what() << endl;
bSuccess = false;
}
return bSuccess;
}
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