/*
 *     xDMS  v1.0  -  Portable DMS archive unpacker  -  Public Domain
 *     Written by     Andre R. de la Rocha  <adlroc@usa.net>
 *
 *     Run Length Encoding decompression function used in most
 *     modes after decompression by other algorithm
 *
 */

#include <string.h>
#include "cdata.h"
#include "u_rle.h"



USHORT Unpack_RLE(UCHAR *in, UCHAR *out, USHORT origsize){
	USHORT n;
	UCHAR a,b, *outend;

	outend = out+origsize;
	while (out<outend){
		a = *in++;
		if (a != 0x90) {
			*out++ = a;
		} else {
			b = *in++;
			if (b == 0) {
				*out++ = a;
			} else {
				a = *in++;
				if (b == 0xff) {
					n = *in++;
					n = (USHORT)((n<<8) + *in++);
				} else {
					n = b;
				}
				if (out+n > outend) return 1;
				memset(out,a,(size_t) n);
				out += n;
			}
		}
	}
	return 0;
}