walkchain

#!/usr/bin/php
<?php
/**
 * walkchain
 *
 * Walks through the blockchain and prints out the contents of each record.
 *
 * No verification of the blockchain validity is performed; this tool simply reads
 * each of the records from the blockchain ordered as they are stored on disk.
 *
 *
 */
date_default_timezone_set('UTC');
define('_magic', 0xD5E8A97F);
define('_hashalg', 'sha256');
define('_hashlen', 32);

define('_fn', 'blockchain.dat');

if (!file_exists(_fn)) exit("Can't open "._fn);
$size = filesize(_fn);
$fp = fopen(_fn,'rb');

$height = 0;
while (ftell($fp) < $size) {

	$header = fread($fp, (13+_hashlen));

	$magic = unpack32($header,0);
	$version = ord($header[4]);
	$timestamp = unpack32($header,5);
	$prevhash = bin2hex(substr($header,9,_hashlen));
	$datalen = unpack32($header,-4);
	$data = fread($fp, $datalen);
	$hash = hash(_hashalg, $header.$data);

	print "height...... ".++$height."\n";
	print "magic....... ".dechex($magic)."\n";
	print "version..... ".$version."\n";
	print "timestamp... ".$timestamp." (".date("H:i:s m/d/Y",$timestamp).")\n";
	print "prevhash.... ".$prevhash."\n";
	print "blockhash... ".$hash."\n";
	print "datalen..... ".$datalen."\n";
	print "data........ ".wordwrap($data, 100)."\n\n";

}
fclose($fp);

function unpack32($data,$ofs) {
	return unpack('V', substr($data,$ofs,4))[1];
}