Ticket #30633: 30633.diff

src/wp-includes/compat.php

@@ -13 +13 @@
         }
 }
 
+if ( ! function_exists( 'mb_strlen' ) ) {
+        /**
+         * Returns string length.
+         *
+         * @since 4.2.0
+         *
+         * @param string $str      The string being checked for length.
+         * @param string $encoding Optional. The character encoding. Default empty.
+         * @return int String length.
+         */
+        function mb_strlen( $str, $encoding = '' ) {
+                if ( empty( $encoding ) ) {
+                        $encoding = get_option( 'blog_charset' );
+                }
+
+                if ( in_array( strtolower( $encoding ), array( 'utf8', 'utf-8' ) ) ) {
+                        $str = utf8_decode( $str );
+                }
+
+                return strlen( $str );
+        }
+}
+
 if ( !function_exists('mb_substr') ):
         function mb_substr( $str, $start, $length=null, $encoding=null ) {
                 return _mb_substr($str, $start, $length, $encoding);