#include <fstream.h>
#include <stdlib.h>
#include <stdio.h>
#include <conio.h>
#include <winsock2.h>

#define GENERAL_PACKET 0
#define LOGIN_PACKET   1
#define CHAT_PACKET    2
#define FILE_PACKET    3

//#define DEBUG          1


class GeneralPacket
{
	public:
		int isize;
		int itype;
};

class LoginPacket : public GeneralPacket
{
	public:
		char szName[64];
		char szPass[64];
};

class TextMsg : public GeneralPacket
{
	public:
		char message[512];
		char szName[64];
};

class FilePacket : public GeneralPacket
{
	public:
		char *fileData;
		char fileName[64];
};

void sendPacket(int pSize, char* packet, SOCKET outSocket)
{
	if(send(outSocket, packet, pSize, 0))
	{
		cout << "Send Passed\n";
		flush(cout);
	}
	else
	{
		cout << "Send Failed\n";
		flush(cout);
	}
}

void setupSockets();
void clientThread(void *param);
void listenThread(void *param);

int g_iQuit = 0;
HANDLE g_hListenThread;
DWORD dwListenThreadID;
HANDLE g_hClientThread;
DWORD dwClientThreadID;

class serverSocket
{
	public:
		void Bind(int iPort);
		void startup();
	private:
		SOCKET mySocket;
};

void main()
{
	WORD version = MAKEWORD(2,2);
	WSADATA wsaData;
	serverSocket srvSocket;
	g_iQuit = 0;

	if(WSAStartup(version, &wsaData) != 0)
	{
		cout << "WSAStartup() failed\n";
		flush(cout);
	}
	
	cout << "Starting Server...\n";
	flush(cout);
	srvSocket.startup();

	while(true)
	{
		// Wait for user to hit quit

	}

	WaitForSingleObject(g_hListenThread, INFINITE);
	CloseHandle(g_hListenThread);
	cout << "Listening Thread Closed\n";
	flush(cout);
}

void serverSocket::startup()
{
	Bind(4000);

	cout << "Starting listen thread\n";
	flush(cout);
	g_hListenThread = CreateThread(NULL, 
					NULL, 
					(LPTHREAD_START_ROUTINE)&listenThread,
					(VOID*)mySocket,
					NULL,
					&dwListenThreadID);
}

void serverSocket::Bind(int iPort)
{
	sockaddr_in saServerAddress;
		
	mySocket = socket(AF_INET, SOCK_STREAM, 0);

	if(mySocket == INVALID_SOCKET)
	{
		cout << "Error at socket(): " << WSAGetLastError() << "\n";
		flush(cout);
		return;
	}

	memset(&saServerAddress, 0, sizeof(sockaddr_in));

	saServerAddress.sin_family = AF_INET;
	saServerAddress.sin_addr.s_addr = htons(INADDR_ANY);
	saServerAddress.sin_port = htons(iPort);

	if(bind(mySocket, (sockaddr*) &saServerAddress, sizeof(sockaddr)) == SOCKET_ERROR)
	{
		#ifdef DEBUG
			cout << "Error at bind(): " << WSAGetLastError() << "\n";
			flush(cout);
		#endif
	}
	else
		return;
}

void listenThread(void *param)
{
	SOCKET listeningSocket = (SOCKET)param;

	#ifdef DEBUG
		cout << "Entering listening thread\n";
		flush(cout);
	#endif

	int nRet;
	int size = sizeof(SOCKADDR_IN);
	SOCKADDR addr_Cli;
	SOCKET client;

	nRet = listen(listeningSocket, 10);

	if(nRet == INVALID_SOCKET)
	{
		#ifdef DEBUG
			cout << "Error at listen\n";
			cout << "Last Error: " << WSAGetLastError() << "\n";
			flush(cout);
		#endif

		ExitThread(0);
	}
	else
	{
		#ifdef DEBUG
			cout << "Listen passed\n";
			flush(cout);
		#endif
	}

	while(g_iQuit != 1)
	{
		client = accept(listeningSocket, (struct sockaddr*)&addr_Cli, &size);
		if(client == INVALID_SOCKET)
		{
			#ifdef DEBUG
				cout << "Error at accept in listening thread\n";
				flush(cout);
				ExitThread(0);
			#endif
		}
		else
		{
			cout << "Accepted client\n";
			g_hClientThread = CreateThread(NULL,
							NULL,
							(LPTHREAD_START_ROUTINE)&clientThread,
							(void*)client,
							NULL,
							&dwClientThreadID);
		}

		client = INVALID_SOCKET;
	}

	closesocket(listeningSocket);
	closesocket(client);

	#ifdef DEBUG
		cout << "Exiting Listening Thread\n";
		flush(cout);
	#endif
}

void clientThread(void *param)
{
	SOCKET client = (SOCKET)param;
	#ifdef DEBUG
		cout << "Entering Client Thread\n";
		flush(cout);
	#endif

	char *recvData = NULL;
	GeneralPacket *PGen = NULL;
	LoginPacket *Login = NULL;
	char uName[64];
	strcpy(uName, "NULL");

	recvData = new char[32768];
	int recvSize = -1;

	while(g_iQuit != 1)
	{
		recvSize = recv(client, recvData, 32768, 0);

		if(recvSize == 0)
		{
			if(uName != "NULL")
				cout << "Client, " << uName << ", has disconnected\n";
			flush(cout);
			shutdown(client, SD_SEND);
			closesocket(client);
			#ifdef DEBUG
				cout << "Exiting client thread\n";
				flush(cout);
			#endif
			ExitThread(0);
		}
		else if(recvSize == SOCKET_ERROR)
		{
			cout << "Receive failed\n";
			cout << "Last Error: " << WSAGetLastError() << "\n";
			flush(cout);
			ExitThread(0);
		}

		PGen = (GeneralPacket*)recvData;

		#ifdef DEBUG
			cout << "Amount of data received: " << recvSize << "\n";
		#endif

		if(PGen->itype == LOGIN_PACKET)
		{
			#ifdef DEBUG
				cout << "Received a Login Packet\n";
				cout << "at a size of: " << recvSize << "\n";
				flush(cout);
			#endif

			Login = (LoginPacket*)recvData;

			strcpy(uName, Login->szName);
			cout << "User logged in: " << Login->szName << "\n";
			flush(cout);
		}
		else if(PGen->itype == CHAT_PACKET)
		{
			TextMsg *MESSAGE;
			MESSAGE = (TextMsg*)recvData;
			#ifdef DEBUG
				cout << "Received a chat packet\n";
			#endif
			cout << MESSAGE->szName << ": " << MESSAGE->message << "\n" << flush;
		} 
		else if(PGen->itype == FILE_PACKET)
		{
			FilePacket *File = NULL;
			File = (FilePacket*)recvData;
			cout << "Receiving a file of size " << File->isize << "\n";
			ofstream prnt;
			prnt.open("ftest.txt");
			prnt << File->fileData;
			cout << "File Data: " << File->fileData << endl;
			prnt.close();
			cout.flush();
		}
		else
		{
			cout << "Unrecognized Packet\n";
			flush(cout);
		}
	}

	closesocket(client);

	#ifdef DEBUG
		cout << "Exiting Client Thread\n";
		flush(cout);
	#endif
}
/[source]

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