#!/usr/local/bin/perl -w

# Warn about a possibly invalid hex file (does not check checksums)
#
# Usage: chkhex < file.hex

$linecount = 0;
$nextaddr = 0;
$eof = 0;

while (<>)
{
	++$linecount;

	chomp;
	$bytes = ((length) - 1) / 2;
	
	# Check line length
	if ((length) < 11)
	{
		print "Line $linecount is too short to be a valid hex record\n";
		next;
	}
	
	# Check for : at beginning of line
	if (substr($_, 0, 1) ne ":")
	{
		print "Line $linecount: line does not begin with ':'\n";
		next;
	}
	
	# Check record type
	$record = hex(substr($_, 7, 2));
	if (($record != 0) and ($record != 1))
	{
		printf "Line $linecount: Record type is %2.2X, not 00 or 01.\n",
		       $record;
	}
	
	# EOF record is a special case
	if ($record == 1)
	{
		if (lc($_) ne ":00000001ff")
		{
			print ("Line $linecount: invalid EOF record.\n");
			next;
		}
		else
		{
			$eof = 1;
			last;
		}
	}
	
	# Check length
	$length = hex(substr($_, 1, 2));
	if ($length != $bytes - 5)
	{
		printf "Line $linecount: Length field is %2.2X but should be %2.2X\n",
		        $length, ($bytes-5);
	}
	
	# Check address
	$addr = hex(substr($_, 3, 4));
	if ($addr != $nextaddr)
	{
		printf "Line $linecount: Address field is %4.4X but expected address was %4.4X\n",
		        $addr, $nextaddr;
	}
	
	# Calculate next address
	$nextaddr = $addr + $length;
}

if ($eof != 1)
{
	print "No EOF record in hex file.\n";
}


print "Check done.\n";