[ticket/9669] Add native Normalizer support

PHP 5.3 includes the previous pecl extension "intl" which has a native
UTF-8 normalizer.

PHPBB3-9669

phpBB/includes/utf/utf_tools.php

@@ -1712,15 +1712,17 @@ function utf8_case_fold_nfc($text, $option = 'full')
 	return $text;
 }
 
-/**
+if (!extension_loaded('intl'))
-* A wrapper function for the normalizer which takes care of including the class if required and modifies the passed strings
-* to be in NFC (Normalization Form Composition).
-*
-* @param	mixed	$strings	a string or an array of strings to normalize
-* @return	mixed				the normalized content, preserving array keys if array given.
-*/
-function utf8_normalize_nfc($strings)
 {
+	/**
+	* A wrapper function for the normalizer which takes care of including the class if required and modifies the passed strings
+	* to be in NFC (Normalization Form Composition).
+	*
+	* @param	mixed	$strings	a string or an array of strings to normalize
+	* @return	mixed				the normalized content, preserving array keys if array given.
+	*/
+	function utf8_normalize_nfc($strings)
+	{
 		if (empty($strings))
 		{
 			return $strings;
@@ -1755,6 +1757,49 @@ function utf8_normalize_nfc($strings)
 		}
 
 		return $strings;
+	}
+}
+else
+{
+	/**
+	* wrapper around PHP's native normalizer from intl
+	* previously a PECL extension, included in the core since PHP 5.3.0
+	* http://php.net/manual/en/normalizer.normalize.php
+	*
+	* @param	mixed	$strings	a string or an array of strings to normalize
+	* @return	mixed				the normalized content, preserving array keys if array given.
+	*/
+	function utf8_normalize_nfc($strings)
+	{
+		if (empty($strings))
+		{
+			return $strings;
+		}
+
+		if (!is_array($strings))
+		{
+			$strings = Normalizer::normalize($strings);
+		}
+		if (is_array($strings))
+		{
+			foreach ($strings as $key => $string)
+			{
+				if (is_array($string))
+				{
+					foreach ($string as $_key => $_string)
+					{
+						$strings[$key][$_key] = Normalizer::normalize($strings[$key][$_key]);
+					}
+				}
+				else
+				{
+					$strings[$key] = Normalizer::normalize($strings[$key]);
+				}
+			}
+		}
+
+		return $strings;
+	}
 }
 
 /**