СПО ЛВС – Системное программное обеспечение ЛВС / Лаба 4-8 TCP&UDP file transferer / TCP client-server / TCPServer / TCPServer / main

#include <winsock.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <string>
#include <fstream>
#include <ctime>

#pragma comment (lib, "ws2_32") 

#define		MAX_CONNECTION_COUNT	2
#define		MESSAGE_LENGTH			1024 * 4
#define		IP						"192.168.1.2"
#define		PORT					10001
using namespace std;
long sended = 0;

void Initialization()
{
	WSADATA WsaDat;
    if (WSAStartup(MAKEWORD(1, 1), &WsaDat) != 0)
    	printf("WSA Initialization failed. Error code: %d", WSAGetLastError());
}

SOCKET CreateSocket()
{
	SOCKET sock;
	if (INVALID_SOCKET == (sock = socket (AF_INET, SOCK_STREAM, IPPROTO_TCP) ) )
	{		
		printf("Create socket error. Error code: %d", WSAGetLastError());
		return NULL;
	}
	else return sock;	
}

void BindSocket(SOCKET sock)
{
	sockaddr_in name;
    ZeroMemory (&name, sizeof (name));
    name.sin_family = AF_INET;
    name.sin_addr.S_un.S_addr = inet_addr (IP);
    name.sin_port = htons(PORT);
	if (SOCKET_ERROR == bind (sock, (sockaddr* ) &name, sizeof (name)))
    	printf("Bind socket error. Error code: %d", WSAGetLastError());
}

void ListenSocket(SOCKET sock)
{
	if (listen(sock, MAX_CONNECTION_COUNT) != 0)
	{
		printf("Listen socket error. Error code: %d", WSAGetLastError());
		return;
	}
}

SOCKET AcceptSocket(SOCKET listenSocket)
{
	sockaddr_in clientData;
	ZeroMemory(&clientData, sizeof (clientData));
	int lengthData = sizeof (clientData);
	SOCKET clientSocket = accept (listenSocket, (sockaddr* ) &clientData, &lengthData);
	if(clientSocket == INVALID_SOCKET )
	{
		printf("Accept socket error. Error code: %d", WSAGetLastError());
		return NULL;
	}
	else return clientSocket;	
}

bool SendData(SOCKET clientSocket, char* serverMessage)
{ 
	if(send(clientSocket, serverMessage, strlen(serverMessage), 0) == SOCKET_ERROR)
	{
		closesocket(clientSocket);
		return false;
    }
	return true;
}

int GetFileData(SOCKET sock,string fileName, long position)
{
	std::ifstream file(fileName, ios::in | ios::binary);
    if (!file.is_open()) 
          return NULL;
    
	char memblock[MESSAGE_LENGTH+1];
    file.seekg (position, ios::beg);
    file.read (memblock, MESSAGE_LENGTH);
	long readed = file.gcount();
    file.close();
	
	memblock[readed] = '\0';
	if(readed > 0)
	{
		if(send(sock, memblock, readed, 0) == SOCKET_ERROR)
		{
			closesocket(sock);
			return 1;
		}
		sended += readed;
		return 0;
	}
	else 
	{
		if(position == 0)
		{
			SendData(sock, "404 FILE NOT FOUND\r\n\0");
			return 4;
		}
		SendData(sock, "102 ALL SENDED\r\n\0");
		return 1;
	}
	return 0;
}

int ParseRequest(SOCKET clientSocket, string message)
{
	if(message.length() < 1)
	{
		return 4;
	}
	string request[3] = {"","",""};
	int index1 = 0, index2 = 0, i = 0;
	while(1)
	{
		index2 = message.find("\n\r", index2);
		if(index2 > 0 && index2 < message.length())
		{
			request[i] = message.substr(index1 ,index2 - index1);
			index2 += 2;
			index1 = index2;
			i++;
			if(i == 3) break;
		}
	}

	srand(time(0));
	int is_oob = rand() % 2;

	if(is_oob == 0)
	{	
		send(clientSocket, "a", 1, MSG_OOB);
		printf("OOB Send, bytes sent: %ld \n", sended);
		return 0;
	}

	if(request[0].compare("GET") == 0)
	{
		long position = atol(request[2].c_str());
		return GetFileData(clientSocket,request[1], position);		
	}
	else
	{
		SendData(clientSocket, "403 WRONG REQUEST\r\n\0");
		return 4;	
	}	
	return 0;
}

string ReceiveData(SOCKET clientSocket)
{
	char* tmpMessage = new char[MESSAGE_LENGTH];
	int messageLength;	
	if ((messageLength = recv (clientSocket, tmpMessage, MESSAGE_LENGTH, 0)) == -1 )
	{	
			printf("Recive message error. Error code: %d\n", WSAGetLastError());
			return string();
	}
	string response(tmpMessage,messageLength);
	delete []tmpMessage;
	return response;	
}

void ShowConnectInfo(SOCKET sock)
{
	sockaddr_in addr;
	int addrlen = sizeof(sockaddr);
    getsockname(sock, (sockaddr*)&addr, &addrlen);
	printf ("Connected: %s:%ld\n", inet_ntoa(addr.sin_addr),ntohs(addr.sin_port));			
}

int main(int argc, char *argv[])
{
	do
	{
		printf ("Wait for incoming connections...   ");
		Initialization();
		SOCKET listenSocket = CreateSocket();
		if(listenSocket != NULL)
		{
			BindSocket(listenSocket);
			ListenSocket(listenSocket);			
			SOCKET clientSocket = AcceptSocket(listenSocket);			
			sended = 0;
			if(clientSocket != NULL)
			{					
				ShowConnectInfo(clientSocket);
				while(ParseRequest(clientSocket, ReceiveData(clientSocket)) == 0);
			}
			closesocket (listenSocket);
		}
		closesocket (listenSocket);
		WSACleanup();
	}while(1);
	return 0;
}