diff -r 000000000000 -r d970ebf37754 wp/wp-includes/compat.php
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/wp/wp-includes/compat.php	Wed Nov 06 03:21:17 2013 +0000
@@ -0,0 +1,96 @@
+<?php
+/**
+ * WordPress implementation for PHP functions either missing from older PHP versions or not included by default.
+ *
+ * @package PHP
+ * @access private
+ */
+
+// If gettext isn't available
+if ( !function_exists('_') ) {
+	function _($string) {
+		return $string;
+	}
+}
+
+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);
+	}
+	// 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( '', $chars );
+}
+
+if ( !function_exists('hash_hmac') ):
+function hash_hmac($algo, $data, $key, $raw_output = false) {
+	return _hash_hmac($algo, $data, $key, $raw_output);
+}
+endif;
+
+function _hash_hmac($algo, $data, $key, $raw_output = false) {
+	$packs = array('md5' => 'H32', 'sha1' => 'H40');
+
+	if ( !isset($packs[$algo]) )
+		return false;
+
+	$pack = $packs[$algo];
+
+	if (strlen($key) > 64)
+		$key = pack($pack, $algo($key));
+
+	$key = str_pad($key, 64, chr(0));
+
+	$ipad = (substr($key, 0, 64) ^ str_repeat(chr(0x36), 64));
+	$opad = (substr($key, 0, 64) ^ str_repeat(chr(0x5C), 64));
+
+	$hmac = $algo($opad . pack($pack, $algo($ipad . $data)));
+
+	if ( $raw_output )
+		return pack( $pack, $hmac );
+	return $hmac;
+}
+
+if ( !function_exists('json_encode') ) {
+	function json_encode( $string ) {
+		global $wp_json;
+
+		if ( !is_a($wp_json, 'Services_JSON') ) {
+			require_once( ABSPATH . WPINC . '/class-json.php' );
+			$wp_json = new Services_JSON();
+		}
+
+		return $wp_json->encodeUnsafe( $string );
+	}
+}
+
+if ( !function_exists('json_decode') ) {
+	function json_decode( $string, $assoc_array = false ) {
+		global $wp_json;
+
+		if ( !is_a($wp_json, 'Services_JSON') ) {
+			require_once( ABSPATH . WPINC . '/class-json.php' );
+			$wp_json = new Services_JSON();
+		}
+
+		$res = $wp_json->decode( $string );
+		if ( $assoc_array )
+			$res = _json_decode_object_helper( $res );
+		return $res;
+	}
+	function _json_decode_object_helper($data) {
+		if ( is_object($data) )
+			$data = get_object_vars($data);
+		return is_array($data) ? array_map(__FUNCTION__, $data) : $data;
+	}
+}