read.pl

#!/usr/bin/perl
use strict;
use warnings;
use 5.010;
use Time::Piece;
use bigint qw/hex/;

my $blocknr = 0;
my $loop = 0;

my $num_args = $#ARGV + 1;
if ($num_args != 1) {
	print "Usage: read.pl bitcoin_file\n\n";
	exit;
}

my $file=$ARGV[0];
open my $fh, '<', $file or die "File not found: $!";

binmode($fh);

while (read ($fh, my $buffer, 4) != 0) {
	next unless ((unpack 'H*', $buffer) eq "f9beb4d9");

	print "Press enter to go to next block.\n";
	my $next = <STDIN>;

	#Blocknr.
	$blocknr = $blocknr + 1;
	print "### Block number: $blocknr ###\n";

	#Read MagicNR
	my $magicnr = unpack 'H*', $buffer;
	print "Magicnr = $magicnr\n";

	#Read Blocksize
	read ($fh, $buffer, 4);
	my $blocksize = unpack 'i', $buffer;
	print "Blocksize = $blocksize\n";

	#Read Version
	read ($fh, $buffer, 4);
	my $version = unpack 'i', $buffer;
	print "Version = $version\n";

	#Hash Prev Block
	read ($fh, $buffer, 32);
	my @hashprev = unpack 'H*', $buffer;
	print "Hash Prev Block = ";
	for (@hashprev){
		my $rev = join '', reverse m/([[:xdigit:]]{2})/g;
	    print "$rev\n";
	}
	
	#Hash Merkel Root
	read ($fh, $buffer, 32);
	my @hashmerkel = unpack 'H*', $buffer;
	print "Hash Merkel Root = ";
	for (@hashmerkel){
		my $rev = join '', reverse m/([[:xdigit:]]{2})/g;
	    print "$rev\n";
	}

	#Read Time
	read ($fh, $buffer, 4);
	my $epoch = unpack 'i', $buffer;
	my $time = localtime($epoch)->strftime('%F %T');
	print "Time = $time\n";

	#Read Bits
	read ($fh, $buffer, 4);
	my @bits = unpack 'H*', $buffer;
	print "Difficulty (Bits) = ";
	for (@bits){
		my $rev = join '', reverse m/([[:xdigit:]]{2})/g;
	    print "$rev\n";
	}

	#Read Nonce
	read ($fh, $buffer, 4);
	my $nonce = unpack 'I', $buffer;
	print "Nonce = $nonce\n\n";

	#Read varint
	read ($fh, $buffer, 1);
	my $varint = unpack 'H*', $buffer;

	#Choose the length of the transaction counter.
	my $rev;
	if ($varint eq "fd"){
		read ($fh, $buffer, 2);
		my @txcount = unpack 'H*', $buffer;
		for (@txcount){
			$rev = join '', reverse m/([[:xdigit:]]{2})/g;
		}
	}elsif ($varint eq "fe"){
		read ($fh, $buffer, 4);
		my @txcount = unpack 'H*', $buffer;
		for (@txcount){
			$rev = join '', reverse m/([[:xdigit:]]{2})/g;
		}
	} elsif ($varint eq "ff"){
		read ($fh, $buffer, 8);
		my @txcount = unpack 'H*', $buffer;
		for (@txcount){
			$rev = join '', reverse m/([[:xdigit:]]{2})/g;
		}
	} else {
		$rev = $varint;
	}

	my $revDec = sprintf("%d", hex($rev));
	print "Transaction counter = $revDec\n\n";

	#A loop through all Transactions.
	my $txnr = 1;
	while ($txnr <= $revDec) {

		print "### Transaction number = $txnr ###\n";

		#Read TX version
		read ($fh, $buffer, 4);
		my $txversion = unpack 'i', $buffer;
		print "Transaction Version = $txversion\n";

		#Read incounter
		read ($fh, $buffer, 1);
		my $incounter = unpack 'H*', $buffer;
		my $incounterDec = sprintf("%d", hex($incounter));
		print "Input counter = $incounterDec\n\n";

		# A loop to through all the input transactions
		my $in = 1;
		while ($in <= $incounterDec) {

			print "Transaction in number: $in\n";

			#Read Transaction out hash
			read ($fh, $buffer, 32);
			my $TxOutHash = unpack 'H*', $buffer;
			print "Transaction out hash = $TxOutHash\n";

			#Read Transaction out Index
			read ($fh, $buffer, 4);
			my $TxOutIndex = unpack 'H*', $buffer;
			print "Transaction out index = $TxOutIndex\n";

			#Read Script length
			read ($fh, $buffer, 1);
			my $ScriptsLength = unpack 'H*', $buffer;
			my $ScriptsLengthDec = sprintf("%d", hex($ScriptsLength));
			print "Scripts length = $ScriptsLengthDec\n";

			#Read Script
			read ($fh, $buffer, $ScriptsLengthDec);
			my $script = unpack 'H*', $buffer;
			print "Script = $script\n";

			#Enable for script to Ascii
			#my $scriptAscii = pack("H*", $script);
			#print "Script Ascii = $scriptAscii\n";

			#Read Sequence
			read ($fh, $buffer, 4);
			my $sequence = unpack 'H*', $buffer;
			print "Sequence = $sequence\n\n";
			$in = $in + 1;
		}

		#Read outcounter
		read ($fh, $buffer, 1);
		my $outcounter = unpack 'H*', $buffer;
		my $outcounterDec = sprintf("%d", hex($outcounter));
		print "Output counter = $outcounterDec\n\n";
		
		# A loop to through all the output transactions
		my $out = 1;
		while ($out <= $outcounterDec) {

			print "Transaction out number: $out\n";

			#Read Bitcoin value
			read ($fh, $buffer, 8);
			my @bitcoin = unpack 'H*', $buffer;
			print "Bitcoin = ";
			for (@bitcoin){
				my $revBitcoin = join '', reverse m/([[:xdigit:]]{2})/g;
		    		$revBitcoin =~ s/^0+//g; 
				my $bitcoinDec = sprintf("%d", hex($revBitcoin));
				my $bitcoinFull=$bitcoinDec/100000000;
				print "$bitcoinFull\n";
				print "Bitcoin smallest unit: $bitcoinDec\n";
			}

			#Read PK script length
			read ($fh, $buffer, 1);
			my $PKScriptLength = unpack 'H*', $buffer;
			my $PKScriptLengthDec = sprintf("%d", hex($PKScriptLength));
			print "PK Script length = $PKScriptLengthDec\n";

			#Read PK Script
			read ($fh, $buffer, $PKScriptLengthDec);
			my $PKScript = unpack 'H*', $buffer;
			print "PK Script = $PKScript\n";
			$out = $out + 1;
		}

		#Read Locktime
		read ($fh, $buffer, 4);
		my $Locktime = unpack 'H*', $buffer;
		print "Locktime = $Locktime\n\n";

		$txnr = $txnr + 1;
	}
	$loop = $loop + 1;
}