/functions/ord.php

<?php

namespace utf8;


/**
 * UTF-8 aware alternative to ord.
 *
 * Returns the unicode ordinal for a character
 *
 * @see http://www.php.net/manual/en/function.ord.php#46267
 * @param string $chr UTF-8 encoded character
 * @return int unicode ordinal for the character
 * @package php-utf8
 * @subpackage functions
 */
function ord($chr)
{
	$ord0 = \ord($chr);

	if ($ord0 >= 0 && $ord0 <= 127)
		return $ord0;

	if (!isset($chr[1]))
	{
		trigger_error('Short sequence - at least 2 bytes expected, only 1 seen');
		return false;
	}

	$ord1 = \ord($chr[1]);
	if ($ord0 >= 192 && $ord0 <= 223)
		return ($ord0 - 192) * 64 + ($ord1 - 128);

	if (!isset($chr[2]))
	{
		trigger_error('Short sequence - at least 3 bytes expected, only 2 seen');
		return false;
	}

	$ord2 = \ord($chr[2]);
	if ($ord0 >= 224 && $ord0 <= 239)
		return ($ord0 - 224) * 4096 + ($ord1 - 128) * 64 + ($ord2 - 128);

	if (!isset($chr[3]))
	{
		trigger_error('Short sequence - at least 4 bytes expected, only 3 seen');
		return false;
	}

	$ord3 = \ord($chr[3]);
	if ($ord0 >= 240 && $ord0 <= 247)
		return ($ord0 - 240) * 262144 + ($ord1 - 128) * 4096 + ($ord2 - 128) * 64 + ($ord3 - 128);

	if (!isset($chr[4]))
	{
		trigger_error('Short sequence - at least 5 bytes expected, only 4 seen');
		return false;
	}

	$ord4 = \ord($chr[4]);
	if ($ord0 >= 248 && $ord0 <= 251)
		return ($ord0 - 248) * 16777216 + ($ord1 - 128) * 262144 + ($ord2 - 128) * 4096 + ($ord3 - 128) * 64 + ($ord4 - 128);

	if (!isset($chr[5]))
	{
		trigger_error('Short sequence - at least 6 bytes expected, only 5 seen');
		return false;
	}

	if ($ord0 >= 252 && $ord0 <= 253)
		return ($ord0 - 252) * 1073741824 + ($ord1 - 128) * 16777216 + ($ord2 - 128) * 262144 + ($ord3 - 128) * 4096 + ($ord4 - 128) * 64 + (\ord($chr[5]) - 128);

	if ($ord0 >= 254 && $ord0 <= 255)
	{
		trigger_error('Invalid UTF-8 with surrogate ordinal '.$ord0);
		return false;
	}
}