Problem in Encrypting the data in the file

See more:

C++

MFC

Hello,

I have developed an application in which i have to load a file and encrypt the data in the file.If i load the file which is having 3 to 5 lines of data then the file is encrypting properly but if the data in the file is more than one page then my application is getting crashed while encrypting.Below is my code ,can some one help me in solving this.Thank you in Advance

CString FunctionEncrypt(CString str)
{
	CString sPath = L"D:\\";


	//Getting the name from the given path
	CString sData = str;
	CString sComPath;
	int iLen = sData.GetLength();
	int iVal = sData.ReverseFind(_T('.'));
	iLen = iLen - iVal;
	sData = sData.Left(iVal);
	iLen = sData.GetLength();
	iVal = sData.ReverseFind(_T('\\'));
	iLen = iLen - iVal;
	sData = sData.Right(iLen);
	iLen = sData.GetLength();
	iVal = sData.ReverseFind(_T('\\'));
	iLen = iLen - iVal;
	sData = sData.Right(iLen-1);
	sComPath = sPath + L"test";

	//Getting the name from the given path

	//string encrypt_decrypt[] = {"encrypt","decrypt"}, buffer, key, newbuffer = "";
	string encrypt_decrypt[] = {"decrypt"}, buffer, key, newbuffer = "";
	char filename[MAX_PATH];
	char OrgFileName[MAX_PATH];
	char OutputName[MAX_PATH];
	char encryptmap[10000];
	int maplength;
	ofstream out;
//	ifstream in;
	sprintf_s(filename, "%s", CT2CA(str));
	sprintf_s(OutputName, "%s", CT2CA(sComPath));
	key = "abcd1234";
	
	do
	{
		in.open(filename);
		strcpy(OrgFileName, filename);
		if (in.fail())           
		{
			in.open(filename);
		}

		//Enter the name that you want your Output file to be named
		out.open(OutputName);

		//Checks the length of the key for the encryption to be done		
		if (key.length()>128)
		{
			cin >> key;
		}

		maplength=key.length();

		mapitE(key,encryptmap);
		//char line[256];
		
		getline(in,buffer);
		//getline(in,sizeof(buffer));
			
		while(in)
		{ 
			encryptdecrypt(buffer,encryptmap,maplength,newbuffer);
			out << newbuffer;
			newbuffer.erase(0);
			getline(in,buffer);
		}

		out.close();
		in.close();
		in.clear();
		out.clear();
		newbuffer.erase(0);
		remove(OrgFileName);		
	}while (FALSE);
	return sData;
}

void encryptdecrypt(string buffer,char map[MAX_PATH],int len,string& newbuffer)
{
	int i=0;
	char t;
	char code;
	int iCount = buffer.length();
	for (i=0;i<icount;i++)>
	{
		if(isalpha(buffer[i]))
		{
			if(islower(buffer[i]))
			{
				code='a';
			}
			else
			{
				code='A';
			}

		t=buffer[i]-code;
		t=t+map[i%len];
		t=t%26;
		t=t+code;
		newbuffer.push_back(t);
		}
		else
		{
		newbuffer.push_back(buffer[i]);
		}
	}
	newbuffer.push_back('\n');
}


void mapitE(string key,char map[MAX_PATH])
{
	int i;
	int iC = key.length();
	for (i=0;i<ic;i++)>
	map[i]=key[i]-'a';
}

void mapitD(string key,char map[MAX_PATH])
{
	int i;
	int iCnt = key.length();
	for (i=0;i<icnt;i++)>
   	map[i]=26-(key[i]-'a');
}