codec_apch.cpp

#include "codec.h"
#include "log.h"
#include <string.h>

using namespace std;
/* mbex is a codec for some editing data I cannot find documentation for.
 * for the few examples I got they are very small packets (8, 10, 100 bytes
 * large packets included crec and cist atoms.
 * Examples:
 *
 * Length 8: 00 00 00 08   00 00 00 00   01 3E 15 29
 * Length 10: 00 00 00 0A   00 00 00 01   00 06 00 00 23 95
 * Length 100: 00 00 00 64    00 00 00 01   00 00 00 5C  63 72 65 63  00 00 00 54  63 69 74 73  00 00 00 0C  00 00 00 02  00 00 00 01
 */

Match Codec::apchMatch(const unsigned char *start, int maxlength) {

	Match match;
	uint32_t length = readBE<uint32_t>(start);

	if(!strncmp((char *)start + 4, "icpf", 4)) {
		match.length = length;
		match.chances  = 1e30;
		return match;
	}
	return match;
}

Match Codec::apchSearch(const unsigned char *start, int maxlength) {
	Match match;
	const unsigned char *end = start + maxlength - 8;
	const  unsigned char *current = start;
	while(current < end) {
		if(!strncmp((char *)current + 4, "icpf", 4)) {
			match.offset = current - start;
			match.chances  = 1e30;
			return match;
		}
		current++;
	}
	return match;
}