RouterOS\Helpers\BinaryStringHelper::IntegerToNBOBinaryString()

Complexity

Conditions	5
Paths	6

Size

Total Lines

36

Duplication

Lines	0
Ratio	0 %

Code Coverage

Tests	12
CRAP Score	5

Importance

Changes

0

<?php
    public static function IntegerToNBOBinaryString($value): string
    {
        // Initialize an empty string
        $buffer = '';

        // Lets start from the most significant byte
        for ($i = (PHP_INT_SIZE - 1); $i >= 0; $i--) {
            // Prepare a mask to keep only the most significant byte of $value
            $mask = 0xFF << ($i * 8);

            // If the most significant byte is not 0, the final string must contain it
            // If we have already started to construct the string (i.e. there are more signficant digits)
            //   we must set the byte, even if it is a 0.
            //   0xFF00FF, for example, require to set the second byte byte with a 0 value
            if (($value & $mask) || $buffer !== '') {
                // Get the current byte by shifting it to least significant position and add it to the string
                // 0xFF12345678 => 0xFF
                $byte   = $value >> (8 * $i);
                $buffer .= chr($byte);

                // Set the most significant byte to 0 so we can restart the process being shure
                // that the value is left padded with 0
                // 0xFF12345678 => 0x12345678
                // -1 = 0xFFFFF.... (number of F depend of PHP_INT_SIZE )
                $mask  = -1 >> ((PHP_INT_SIZE - $i) * 8);
                $value &= $mask;
            }
        }

        // Special case, 0 will not fill the buffer, have to construct it manualy
        if (0 === $value) {
            $buffer = chr(0);
        }

        return $buffer;
    }
}