PSI 01 RECIVER

// UDP_Communication_Framework.cpp : Defines the entry point for the console application.
//

#pragma comment(lib, "ws2_32.lib")
#include "stdafx.h"
#include <winsock2.h>
#include "ws2tcpip.h"

#include<iostream>
#include<fstream>
#include<string>
#include<stdlib.h>
using namespace std;

#define TARGET_IP   "147.32.221.22"

#define BUFFERS_LEN 1024

//#define SENDER
#define RECEIVER

#ifdef SENDER
#define TARGET_PORT 5555
#define LOCAL_PORT 8888
#endif // SENDER

#ifdef RECEIVER
#define TARGET_PORT 8888
#define LOCAL_PORT 5555
#endif // RECEIVER


void InitWinsock()
{
	WSADATA wsaData;
	WSAStartup(MAKEWORD(2, 2), &wsaData);
}

int processHeader(char* buffer) {
	int ret = 0;

	for (int i = 0; i <= 32; i++) {
		int tmp = (int)buffer[i] - 48;
		//printf("%d\n", tmp);
		if (tmp < 10 && tmp >= 0) {
			ret = ret * 10 + (int)tmp;
		}
	}


	return ret;
}

//**********************************************************************
int main()
{
	SOCKET socketS;

	InitWinsock();

	struct sockaddr_in local;
	struct sockaddr_in from;

	int fromlen = sizeof(from);
	local.sin_family = AF_INET;
	local.sin_port = htons(LOCAL_PORT);
	local.sin_addr.s_addr = INADDR_ANY;


	socketS = socket(AF_INET, SOCK_DGRAM, 0);
	if (bind(socketS, (sockaddr*)&local, sizeof(local)) != 0) {
		printf("Binding error!\n");
		getchar(); //wait for press Enter
		return 1;
	}
	//**********************************************************************
	char buffer_rx[BUFFERS_LEN];
	char buffer_tx[BUFFERS_LEN];

#ifdef SENDER

	sockaddr_in addrDest;
	addrDest.sin_family = AF_INET;
	addrDest.sin_port = htons(TARGET_PORT);
	InetPton(AF_INET, _T(TARGET_IP), &addrDest.sin_addr.s_addr);

	int i = 1313;

	sprintf(buffer_tx, "%d", i);

	//strncpy(buffer_tx, "something", BUFFERS_LEN); //put some data to buffer
	printf("Sending packet.\n");
	sendto(socketS, buffer_tx, strlen(buffer_tx), 0, (sockaddr*)&addrDest, sizeof(addrDest));

	closesocket(socketS);

#endif // SENDER

#ifdef RECEIVER

	int messageLength;
	char name[BUFFERS_LEN];

	strncpy(buffer_rx, "", BUFFERS_LEN);
	printf("Recieving ...\n");

	// get name
	if (recvfrom(socketS, buffer_rx, sizeof(buffer_rx), 0, (sockaddr*)&from, &fromlen) == SOCKET_ERROR) {
		printf("Header socket error!\n");
		getchar();
		return 1;
	}
	else {
		printf("Name: %s!\n", buffer_rx);
	}

	strcpy(name, buffer_rx);

	// get size
	if (recvfrom(socketS, buffer_rx, sizeof(buffer_rx), 0, (sockaddr*)&from, &fromlen) == SOCKET_ERROR) {
		printf("Header socket error!\n");
		getchar();
		return 1;
	}


	else {
		messageLength = processHeader(buffer_rx);
		printf("Size: %d\n", messageLength);
	}

	char* fileBuffer = (char*)malloc(messageLength);

	// init file
	FILE *p_file = fopen(name, "wb");

	// process header, set counter
	int i;
	for (i = 0; i < messageLength / BUFFERS_LEN; i++) {
		strncpy(buffer_rx, "", BUFFERS_LEN);
		if (recvfrom(socketS, buffer_rx, sizeof(buffer_rx), 0, (sockaddr*)&from, &fromlen) == SOCKET_ERROR) {
			printf("Socket error!\n");
			getchar();
			return 1;
		}
		else {
			printf("Data: %i %x\n", i, buffer_rx);
			strncpy(fileBuffer, buffer_rx, BUFFERS_LEN);
			fileBuffer += BUFFERS_LEN;
//			fputs(buffer_rx, p_file);
		}

	}

	if (recvfrom(socketS, buffer_rx, sizeof(buffer_rx), 0, (sockaddr*)&from, &fromlen) == SOCKET_ERROR) {
		printf("Socket error!\n");
		getchar();
		return 1;
	}
	else {
		printf("Data: %i %x\n", i, buffer_rx);
		strncpy(fileBuffer, buffer_rx, messageLength % BUFFERS_LEN + 1);
		fileBuffer -= BUFFERS_LEN * i;
		//			fputs(buffer_rx, p_file);
	}
	//for (int j = 0; j < messageLength; ++j)
		fwrite(fileBuffer, 1, messageLength, p_file);
			//	fprintf(p_file, "%c", fileBuffer[j]);
	//fputs(fileBuffer, p_file);


	fclose(p_file);

	closesocket(socketS);
#endif
	//**********************************************************************

	getchar(); //wait for press Enter
	return 0;
}