From f4cfb30c6afb319113e121618afef6bc32153410 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Roland=20H=C3=A4der?= <roland@mxchange.org>
Date: Mon, 4 Apr 2011 22:19:12 +0000
Subject: [PATCH] Added methods dec2hex()/hex2dec() which are based on user
 comments at php.net documentation website

---
 .../main/class_BaseFrameworkSystem.php        | 101 ++++++++++++++++++
 1 file changed, 101 insertions(+)

diff --git a/inc/classes/main/class_BaseFrameworkSystem.php b/inc/classes/main/class_BaseFrameworkSystem.php
index d092ccbf..7f871069 100644
--- a/inc/classes/main/class_BaseFrameworkSystem.php
+++ b/inc/classes/main/class_BaseFrameworkSystem.php
@@ -1551,6 +1551,107 @@ class BaseFrameworkSystem extends stdClass implements FrameworkInterface {
 	public function getPackageData () {
 		return $this->packageData;
 	}
+
+	/**
+	 * 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	$dec	Decimal number
+	 */
+	function hex2dec ($hex) {
+		// Convert to all lower-case
+		$hex = strtolower($hex);
+
+		// Hexadecimal->Decimal translation array
+		$hexdec = array(
+			'0' => 0,
+			'1' => 1,
+			'2' => 2,
+			'3' => 3,
+			'4' => 4,
+			'5' => 5,
+			'6' => 6,
+			'7' => 7,
+			'8' => 8,
+			'9' => 9,
+			'a' => 10,
+			'b' => 11,
+			'c' => 12,
+			'd' => 13,
+			'e' => 14,
+			'f' => 15
+		);
+
+		// 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 = $hexdec[substr($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	$hex	Hexadecimal string
+	 */
+	function dec2hex ($dec) {
+		// Detect sign (negative/positive numbers)
+		$sign = '';
+		if ($dec < 0) {
+			$sign = '-';
+			$dec = abs($dec);
+		} // END - if
+
+		// Decimal->hexadecimal translation array
+		$hexAlphabet = array(
+			 0 => '0',
+			 1 => '1',
+			 2 => '2',
+			 3 => '3',
+			 4 => '4',
+			 5 => '5',
+			 6 => '6',
+			 7 => '7',
+			 8 => '8',
+			 9 => '9',
+			10 => 'a',
+			11 => 'b',
+			12 => 'c',
+			13 => 'd',
+			14 => 'e',
+			15 => 'f'
+		);
+
+		// Encode the decimal number into a hexadecimal string
+		$hex = '';
+		do {
+			$hex = $hexAlphabet[($dec % 16)] . $hex;
+			$dec /= 16;
+		} while( $dec >= 1 );
+
+		// Return the hexadecimal string
+		return $sign . $hex;
+	}
 }
 
 // [EOF]
-- 
2.30.2