Help Adding Progress Indicator

Hi everyone,

Recently I've been attempting to learn about C++ source code compilation and modifications of existing sources. What I've learned so far is very, very basic.

Some open-source compressors do their compression/decomression without any progress indicator which is rather annoying. By progress indicator, I mean a percentage display like in Nanozip, UDA, RAR, 7z, etc. Is there an easy way to add a progress indicator to display progress during the compression/decompression process?

So, for example, I've been playing with TANGELO 1.0 by Jan Ondrus and CRUSH 1.0 by Ilia sources recently--They are somewhat understandable to me. Is there an easy way to add a progress indicator to be printed while doing compression and decompression? Both programmers chose not to put one in so perhaps it is not so simple of a task?

Any help would be great.
Thanks. :)

A quick example:

_fseeki64(in, 0, SEEK_END);

const __int64 filesize=_ftelli64(in);

rewind(in);



// ...



while ((size=fread(buf, 1, BUF_SIZE, in)>0)

{

    printf("%I64d%% complete\r", (_ftelli64(in)*100)/filesize);



    // ...

}



printf("\n");

For 64-bit values it is perhaps less of a problem (at least for now), but if you use shorter types, it is a good idea to check for over- and underflow. I've used something like:

/*

 * Compute ratio between two numbers.

 */

unsigned int ratio(unsigned long x, unsigned long y)

{

	if (x <= ULONG_MAX / 100) {

		x *= 100;

	}

	else {

		y /= 100;

	}



	if (y == 0) {

		y = 1;

	}



	return (unsigned int) (x / y);

}

Thanks for your help guys!