wp/wp-includes/compat.php
changeset 5 5e2f62d02dcd
parent 0 d970ebf37754
child 7 cf61fcea0001
--- a/wp/wp-includes/compat.php	Mon Jun 08 16:11:51 2015 +0000
+++ b/wp/wp-includes/compat.php	Tue Jun 09 03:35:32 2015 +0200
@@ -13,23 +13,141 @@
 	}
 }
 
-if ( !function_exists('mb_substr') ):
-	function mb_substr( $str, $start, $length=null, $encoding=null ) {
-		return _mb_substr($str, $start, $length, $encoding);
+/**
+ * Returns whether PCRE/u (PCRE_UTF8 modifier) is available for use.
+ *
+ * @ignore
+ * @since 4.2.2
+ * @access private
+ *
+ * @param bool $set - Used for testing only
+ *             null   : default - get PCRE/u capability
+ *             false  : Used for testing - return false for future calls to this function
+ *             'reset': Used for testing - restore default behavior of this function
+ */
+function _wp_can_use_pcre_u( $set = null ) {
+	static $utf8_pcre = 'reset';
+
+	if ( null !== $set ) {
+		$utf8_pcre = $set;
+	}
+
+	if ( 'reset' === $utf8_pcre ) {
+		$utf8_pcre = @preg_match( '/^./u', 'a' );
+	}
+
+	return $utf8_pcre;
+}
+
+if ( ! function_exists( 'mb_substr' ) ) :
+	function mb_substr( $str, $start, $length = null, $encoding = null ) {
+		return _mb_substr( $str, $start, $length, $encoding );
 	}
 endif;
 
-function _mb_substr( $str, $start, $length=null, $encoding=null ) {
-	// the solution below, works only for utf-8, so in case of a different
-	// charset, just use built-in substr
-	$charset = get_option( 'blog_charset' );
-	if ( !in_array( $charset, array('utf8', 'utf-8', 'UTF8', 'UTF-8') ) ) {
-		return is_null( $length )? substr( $str, $start ) : substr( $str, $start, $length);
+/*
+ * Only understands UTF-8 and 8bit.  All other character sets will be treated as 8bit.
+ * For $encoding === UTF-8, the $str input is expected to be a valid UTF-8 byte sequence.
+ * The behavior of this function for invalid inputs is undefined.
+ */
+function _mb_substr( $str, $start, $length = null, $encoding = null ) {
+	if ( null === $encoding ) {
+		$encoding = get_option( 'blog_charset' );
+	}
+
+	// The solution below works only for UTF-8,
+	// so in case of a different charset just use built-in substr()
+	if ( ! in_array( $encoding, array( 'utf8', 'utf-8', 'UTF8', 'UTF-8' ) ) ) {
+		return is_null( $length ) ? substr( $str, $start ) : substr( $str, $start, $length );
+	}
+
+	if ( _wp_can_use_pcre_u() ) {
+		// Use the regex unicode support to separate the UTF-8 characters into an array
+		preg_match_all( '/./us', $str, $match );
+		$chars = is_null( $length ) ? array_slice( $match[0], $start ) : array_slice( $match[0], $start, $length );
+		return implode( '', $chars );
 	}
-	// use the regex unicode support to separate the UTF-8 characters into an array
-	preg_match_all( '/./us', $str, $match );
-	$chars = is_null( $length )? array_slice( $match[0], $start ) : array_slice( $match[0], $start, $length );
-	return implode( '', $chars );
+
+	$regex = '/(
+		  [\x00-\x7F]                  # single-byte sequences   0xxxxxxx
+		| [\xC2-\xDF][\x80-\xBF]       # double-byte sequences   110xxxxx 10xxxxxx
+		| \xE0[\xA0-\xBF][\x80-\xBF]   # triple-byte sequences   1110xxxx 10xxxxxx * 2
+		| [\xE1-\xEC][\x80-\xBF]{2}
+		| \xED[\x80-\x9F][\x80-\xBF]
+		| [\xEE-\xEF][\x80-\xBF]{2}
+		| \xF0[\x90-\xBF][\x80-\xBF]{2} # four-byte sequences   11110xxx 10xxxxxx * 3
+		| [\xF1-\xF3][\x80-\xBF]{3}
+		| \xF4[\x80-\x8F][\x80-\xBF]{2}
+	)/x';
+
+	$chars = array( '' ); // Start with 1 element instead of 0 since the first thing we do is pop
+	do {
+		// We had some string left over from the last round, but we counted it in that last round.
+		array_pop( $chars );
+
+		// Split by UTF-8 character, limit to 1000 characters (last array element will contain the rest of the string)
+		$pieces = preg_split( $regex, $str, 1000, PREG_SPLIT_DELIM_CAPTURE | PREG_SPLIT_NO_EMPTY );
+
+		$chars = array_merge( $chars, $pieces );
+	} while ( count( $pieces ) > 1 && $str = array_pop( $pieces ) ); // If there's anything left over, repeat the loop.
+
+	return join( '', array_slice( $chars, $start, $length ) );
+}
+
+if ( ! function_exists( 'mb_strlen' ) ) :
+	function mb_strlen( $str, $encoding = null ) {
+		return _mb_strlen( $str, $encoding );
+	}
+endif;
+
+/*
+ * Only understands UTF-8 and 8bit.  All other character sets will be treated as 8bit.
+ * For $encoding === UTF-8, the $str input is expected to be a valid UTF-8 byte sequence.
+ * The behavior of this function for invalid inputs is undefined.
+ */
+function _mb_strlen( $str, $encoding = null ) {
+	if ( null === $encoding ) {
+		$encoding = get_option( 'blog_charset' );
+	}
+
+	// The solution below works only for UTF-8,
+	// so in case of a different charset just use built-in strlen()
+	if ( ! in_array( $encoding, array( 'utf8', 'utf-8', 'UTF8', 'UTF-8' ) ) ) {
+		return strlen( $str );
+	}
+
+	if ( _wp_can_use_pcre_u() ) {
+		// Use the regex unicode support to separate the UTF-8 characters into an array
+		preg_match_all( '/./us', $str, $match );
+		return count( $match[0] );
+	}
+
+	$regex = '/(?:
+		  [\x00-\x7F]                  # single-byte sequences   0xxxxxxx
+		| [\xC2-\xDF][\x80-\xBF]       # double-byte sequences   110xxxxx 10xxxxxx
+		| \xE0[\xA0-\xBF][\x80-\xBF]   # triple-byte sequences   1110xxxx 10xxxxxx * 2
+		| [\xE1-\xEC][\x80-\xBF]{2}
+		| \xED[\x80-\x9F][\x80-\xBF]
+		| [\xEE-\xEF][\x80-\xBF]{2}
+		| \xF0[\x90-\xBF][\x80-\xBF]{2} # four-byte sequences   11110xxx 10xxxxxx * 3
+		| [\xF1-\xF3][\x80-\xBF]{3}
+		| \xF4[\x80-\x8F][\x80-\xBF]{2}
+	)/x';
+
+	$count = 1; // Start at 1 instead of 0 since the first thing we do is decrement
+	do {
+		// We had some string left over from the last round, but we counted it in that last round.
+		$count--;
+
+		// Split by UTF-8 character, limit to 1000 characters (last array element will contain the rest of the string)
+		$pieces = preg_split( $regex, $str, 1000 );
+
+		// Increment
+		$count += count( $pieces );
+	} while ( $str = array_pop( $pieces ) ); // If there's anything left over, repeat the loop.
+
+	// Fencepost: preg_split() always returns one extra item in the array
+	return --$count;
 }
 
 if ( !function_exists('hash_hmac') ):
@@ -65,7 +183,7 @@
 	function json_encode( $string ) {
 		global $wp_json;
 
-		if ( !is_a($wp_json, 'Services_JSON') ) {
+		if ( ! ( $wp_json instanceof Services_JSON ) ) {
 			require_once( ABSPATH . WPINC . '/class-json.php' );
 			$wp_json = new Services_JSON();
 		}
@@ -78,7 +196,7 @@
 	function json_decode( $string, $assoc_array = false ) {
 		global $wp_json;
 
-		if ( !is_a($wp_json, 'Services_JSON') ) {
+		if ( ! ($wp_json instanceof Services_JSON ) ) {
 			require_once( ABSPATH . WPINC . '/class-json.php' );
 			$wp_json = new Services_JSON();
 		}
@@ -94,3 +212,38 @@
 		return is_array($data) ? array_map(__FUNCTION__, $data) : $data;
 	}
 }
+
+if ( ! function_exists( 'hash_equals' ) ) :
+/**
+ * Compare two strings in constant time.
+ *
+ * This function was added in PHP 5.6.
+ * It can leak the length of a string.
+ *
+ * @since 3.9.2
+ *
+ * @param string $a Expected string.
+ * @param string $b Actual string.
+ * @return bool Whether strings are equal.
+ */
+function hash_equals( $a, $b ) {
+	$a_length = strlen( $a );
+	if ( $a_length !== strlen( $b ) ) {
+		return false;
+	}
+	$result = 0;
+
+	// Do not attempt to "optimize" this.
+	for ( $i = 0; $i < $a_length; $i++ ) {
+		$result |= ord( $a[ $i ] ) ^ ord( $b[ $i ] );
+	}
+
+	return $result === 0;
+}
+endif;
+
+// JSON_PRETTY_PRINT was introduced in PHP 5.4
+// Defined here to prevent a notice when using it with wp_json_encode()
+if ( ! defined( 'JSON_PRETTY_PRINT' ) ) {
+	define( 'JSON_PRETTY_PRINT', 128 );
+}