Ticket #25259: 25259.diff

src/wp-includes/class-http.php

@@ -166 +166 @@
                 // Construct Cookie: header if any cookies are set
                 WP_Http::buildCookieHeader( $r );
 
+                // Avoid issues where mbstring.func_overload is enabled
+                mbstring_binary_safe_encoding();
+
                 if ( ! isset( $r['headers']['Accept-Encoding'] ) ) {
                         if ( $encoding = WP_Http_Encoding::accept_encoding( $url, $r ) )
                                 $r['headers']['Accept-Encoding'] = $encoding;
@@ -187 +190 @@
                 }
 
                 $response = $this->_dispatch_request( $url, $r );
+
+                reset_mbstring_encoding();
+
                 if ( is_wp_error( $response ) )
                         return $response;
 
@@ -1311 +1317 @@
          * @return int
          */
         private function stream_body( $handle, $data ) {
-                if ( function_exists( 'ini_get' ) && ( ini_get( 'mbstring.func_overload' ) & 2 ) && function_exists( 'mb_internal_encoding' ) ) {
-                        $mb_encoding = mb_internal_encoding();
-                        mb_internal_encoding( 'ISO-8859-1' );
-                }
-
                 $data_length = strlen( $data );
 
                 if ( $this->max_body_length && ( strlen( $this->body ) + $data_length ) > $this->max_body_length )
@@ -1328 +1329 @@
                         $bytes_written = $data_length;
                 }
 
-                if ( isset( $mb_encoding ) )
-                        mb_internal_encoding( $mb_encoding );
-
                 // Upon event of this function returning less than strlen( $data ) curl will error with CURLE_WRITE_ERROR
                 return $bytes_written;
         }

src/wp-includes/functions.php

@@ -4092 +4092 @@
 
         return $charset;
 }
+
+/**
+ * Sets the mbstring internal encoding to a binary safe encoding whne func_overload is enabled.
+ *
+ * When mbstring.func_overload is in use for multi-byte encodings, the results from strlen() and
+ * similar functions respect the utf8 characters, causing binary data to return incorrect lengths.
+ *
+ * This function overrides the mbstring encoding to a binary-safe encoding, and resets it to the
+ * users expected encoding afterwards through the `reset_mbstring_encoding` function.
+ *
+ * It is safe to recursively call this function, however each `mbstring_binary_safe_encoding` call
+ * must be followed up with an equal number of `reset_mbstring_encoding` calls.
+ *
+ * @see reset_mbstring_encoding()
+ *
+ * @since 3.7.0
+ *
+ * @param bool $reset Whether to reset the encoding back to a previously-set encoding.
+ */
+function mbstring_binary_safe_encoding( $reset = false ) {
+        static $encodings = array();
+        static $overloaded = null;
+
+        if ( is_null( $overloaded ) )
+                $overloaded = function_exists( 'ini_get' ) && ( ini_get( 'mbstring.func_overload' ) & 2 ) && function_exists( 'mb_internal_encoding' );
+
+        if ( false === $overloaded )
+                return;
+
+        if ( ! $reset ) {
+                $encoding = mb_internal_encoding();
+                array_push( $encodings, $encoding );
+                mb_internal_encoding( 'ISO-8859-1' );
+        }
+
+        if ( $reset && $encodings ) {
+                $encoding = array_pop( $encodings );
+                mb_internal_encoding( $encoding );
+        }
+}
+
+/**
+ * Resets the mbstring internal encoding to a users previously set encoding.
+ *
+ * @see mbstring_binary_safe_encoding()
+ *
+ * @since 3.7.0
+ */
+function reset_mbstring_encoding() {
+        mbstring_binary_safe_encoding( true );
+}
+ No newline at end of file

src/wp-admin/includes/file.php

@@ -642 +642 @@
 function _unzip_file_pclzip($file, $to, $needed_dirs = array()) {
         global $wp_filesystem;
 
-        // See #15789 - PclZip uses string functions on binary data, If it's overloaded with Multibyte safe functions the results are incorrect.
-        if ( ( ini_get('mbstring.func_overload') & 2 ) && function_exists('mb_internal_encoding') ) {
-                $previous_encoding = mb_internal_encoding();
-                mb_internal_encoding('ISO-8859-1');
-        }
+        mbstring_binary_safe_encoding();
 
         require_once(ABSPATH . 'wp-admin/includes/class-pclzip.php');
 
@@ -654 +650 @@
 
         $archive_files = $archive->extract(PCLZIP_OPT_EXTRACT_AS_STRING);
 
-        if ( isset($previous_encoding) )
-                mb_internal_encoding($previous_encoding);
+        reset_mbstring_encoding();
 
         // Is the archive valid?
         if ( !is_array($archive_files) )