edithex.cpp

cRijndael - Advanced Encryption Standard (AES)

// EditHex.cpp : implementation file
//

#include "stdafx.h"
#include "AESDemo.h"
#include "EditHex.h"


// CEditHex

IMPLEMENT_DYNAMIC(CEditHex, CEdit)
CEditHex::CEditHex() :
	m_State(EMHEX)
{
}

CEditHex::~CEditHex()
{
}


BEGIN_MESSAGE_MAP(CEditHex, CEdit)
	ON_WM_CHAR()
//	ON_CONTROL_REFLECT(EN_MAXTEXT, OnEnMaxtext)
ON_WM_CREATE()
END_MESSAGE_MAP()



// CEditHex message handlers


void CEditHex::OnChar(UINT nChar, UINT nRepCnt, UINT nFlags)
{
	// TODO: Add your message handler code here and/or call default
	// If in Hex Mode, only pass Hex characters
	if(EMHEX==m_State)
	{
		// Block out any editable non-hex characters
		if ((nChar >= 'G' && nChar <= 'Z') || 
			(nChar >= 'g' && nChar <= 'z'))
		{
			// Invalid Hex character, let the user know
			MessageBeep(-1);
		}
		else
		{
			// Valid Hex character, pass it along
			CEdit::OnChar(nChar, nRepCnt, nFlags);
		}
	}
	else
	{		
		CEdit::OnChar(nChar, nRepCnt, nFlags);
	}
}

// Get the data - copies the data to the passed byte pointer and returns the count
int CEditHex::GetData(int *piData)
{
	int nLength;
	
	if (piData)
		nLength = StrToHex(piData);

	return nLength;
}

// Converts the Display string hexidecimal data
int CEditHex::StrToHex(int *piData)
{
	UINT nLength;
	CString strData;

	// Get the text data
	GetWindowText(strData);
	nLength = strData.GetLength();

	// Make sure the text data is hex
	for(int i = 0; i < strData.GetLength(); i++)
	{
		if (-1 == CharToHexInt(strData[i]))
			// Text is not a hex string, return an error
			return -1;
	}


	// Convert data
	for(i = 0; (i < (int)nLength/2) && (i < MAX_BLOCKSIZE); i++)
	{
		piData[i] = 0;
		piData[i] = (CharToHexInt(strData[i<<1])<<4) | (CharToHexInt(strData[(i<<1)+1]));
	}

	return nLength/2;
}

int CEditHex::CharToHexInt(const char str)
{
	if (str >= '0' && str <= '9')
		return (int)((str - '0')&0xff);
	else if (str >= 'A' && str <= 'F')
		return (int)(((str-'A')+0xA)&0xff);
	else
		return -1;
}