Click here to Skip to main content
15,884,629 members
Articles / Desktop Programming / ATL

A File Checksum Shell Menu Extension DLL

Rate me:
Please Sign up or sign in to vote.
4.89/5 (34 votes)
23 May 2008LGPL315 min read 250.9K   6K   116  
Create a File Checksum Shell Menu Extension using ATL and Crypto++
// misc.cpp - written and placed in the public domain by Wei Dai

#include "pch.h"

#ifndef CRYPTOPP_IMPORTS

#include "misc.h"
#include "words.h"
#include <new>

NAMESPACE_BEGIN(CryptoPP)

void xorbuf(byte *buf, const byte *mask, unsigned int count)
{
	if (((size_t)buf | (size_t)mask | count) % WORD_SIZE == 0)
		XorWords((word *)buf, (const word *)mask, count/WORD_SIZE);
	else
	{
		for (unsigned int i=0; i<count; i++)
			buf[i] ^= mask[i];
	}
}

void xorbuf(byte *output, const byte *input, const byte *mask, unsigned int count)
{
	if (((size_t)output | (size_t)input | (size_t)mask | count) % WORD_SIZE == 0)
		XorWords((word *)output, (const word *)input, (const word *)mask, count/WORD_SIZE);
	else
	{
		for (unsigned int i=0; i<count; i++)
			output[i] = input[i] ^ mask[i];
	}
}

unsigned int Parity(unsigned long value)
{
	for (unsigned int i=8*sizeof(value)/2; i>0; i/=2)
		value ^= value >> i;
	return (unsigned int)value&1;
}

unsigned int BytePrecision(unsigned long value)
{
	unsigned int i;
	for (i=sizeof(value); i; --i)
		if (value >> (i-1)*8)
			break;

	return i;
}

unsigned int BitPrecision(unsigned long value)
{
	if (!value)
		return 0;

	unsigned int l=0, h=8*sizeof(value);

	while (h-l > 1)
	{
		unsigned int t = (l+h)/2;
		if (value >> t)
			l = t;
		else
			h = t;
	}

	return h;
}

unsigned long Crop(unsigned long value, unsigned int size)
{
	if (size < 8*sizeof(value))
    	return (value & ((1L << size) - 1));
	else
		return value;
}

#if !(defined(_MSC_VER) && (_MSC_VER < 1300))
using std::new_handler;
using std::set_new_handler;
#endif

void CallNewHandler()
{
	new_handler newHandler = set_new_handler(NULL);
	if (newHandler)
		set_new_handler(newHandler);

	if (newHandler)
		newHandler();
	else
		throw std::bad_alloc();
}

NAMESPACE_END

#endif

By viewing downloads associated with this article you agree to the Terms of Service and the article's licence.

If a file you wish to view isn't highlighted, and is a text file (not binary), please let us know and we'll add colourisation support for it.

License

This article, along with any associated source code and files, is licensed under The GNU Lesser General Public License (LGPLv3)


Written By
Systems / Hardware Administrator
United States United States
This member has not yet provided a Biography. Assume it's interesting and varied, and probably something to do with programming.

Comments and Discussions