+
+ /**
+ * Converts a hexadecimal string, even with negative sign as first string to
+ * a decimal number using BC functions.
+ *
+ * This work is based on comment #86673 on php.net documentation page at:
+ * <http://de.php.net/manual/en/function.dechex.php#86673>
+ *
+ * @param $hex Hexadecimal string
+ * @return $dec Decimal number
+ */
+ public final function hex2dec ($hex) {
+ // Convert to all lower-case
+ $hex = strtolower($hex);
+
+ // Detect sign (negative/positive numbers)
+ $sign = '';
+ if (substr($hex, 0, 1) == '-') {
+ $sign = '-';
+ $hex = substr($hex, 1);
+ } // END - if
+
+ // Decode the hexadecimal string into a decimal number
+ $dec = 0;
+ for ($i = strlen($hex) - 1, $e = 1; $i >= 0; $i--, $e = bcmul($e, 16)) {
+ $factor = self::$hexdec[substr($hex, $i, 1)];
+ $dec = bcadd($dec, bcmul($factor, $e));
+ } // END - for
+
+ // Return the decimal number
+ return $sign . $dec;
+ }
+
+ /**
+ * Converts even very large decimal numbers, also with negative sign, to a
+ * hexadecimal string.
+ *
+ * This work is based on comment #97756 on php.net documentation page at:
+ * <http://de.php.net/manual/en/function.hexdec.php#97756>
+ *
+ * @param $dec Decimal number, even with negative sign
+ * @return $hex Hexadecimal string
+ */
+ public final function dec2hex ($dec) {
+ // Detect sign (negative/positive numbers)
+ $sign = '';
+ if ($dec < 0) {
+ $sign = '-';
+ $dec = abs($dec);
+ } // END - if
+
+ // Encode the decimal number into a hexadecimal string
+ $hex = '';
+ do {
+ $hex = self::$dechex[($dec % 16)] . $hex;
+ $dec /= 16;
+ } while ($dec >= 1);
+
+ // Return the hexadecimal string
+ return $sign . $hex;
+ }
+
+ /**
+ * Converts a ASCII string (0 to 255) into a decimal number.
+ *
+ * @param $asc The ASCII string to be converted
+ * @return $dec Decimal number
+ */
+ public final function asc2dec ($asc) {
+ // Convert it into a hexadecimal number
+ $hex = bin2hex($asc);
+
+ // And back into a decimal number
+ $dec = $this->hex2dec($hex);
+
+ // Return it
+ return $dec;
+ }
+
+ /**
+ * Converts a decimal number into an ASCII string.
+ *
+ * @param $dec Decimal number
+ * @return $asc An ASCII string
+ */
+ public final function dec2asc ($deg) {
+ // First convert the number into a hexadecimal string
+ $hex = $this->dec2hex($deg);
+
+ // Then convert it into the ASCII string
+ $asc = $this->hex2asc($hex);
+
+ // Return it
+ return $asc;
+ }
+
+ /**
+ * Converts a hexadecimal number into an ASCII string. Negative numbers
+ * are not allowed.
+ *
+ * @param $hex Hexadecimal string
+ * @return $asc An ASCII string
+ */
+ public final function hex2asc ($hex) {
+ // Check for length, it must be devideable by 2
+ assert((strlen($hex) % 2) == 0);
+
+ // Walk the string
+ $asc = '';
+ for ($idx = 0; $idx < strlen($hex); $idx+=2) {
+ // Get the decimal number of the chunk
+ $part = hexdec(substr($hex, $idx, 2));
+ $this->debugOutput(__FUNCTION__ . ': part(' . strlen($part) . ')=' . $part);
+
+ // Add it to the final string
+ $asc .= chr($part);
+ } // END - for
+
+ // Return the final string
+ return $asc;
+ }