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[autoinstalls/wordpress.git] / wp-admin / includes / class-wp-upgrader.php
index c70ef66bbb732d4797c32ac0a697b1d5332cd010..485197c49ac213bc20b17484990614134f08de49 100644 (file)
 <?php
 /**
- * A File upgrader class for WordPress.
+ * Upgrade API: WP_Upgrader class
  *
- * This set of classes are designed to be used to upgrade/install a local set of files on the filesystem via the Filesystem Abstraction classes.
- *
- * @link http://trac.wordpress.org/ticket/7875 consolidate plugin/theme/core upgrade/install functions
+ * Requires skin classes and WP_Upgrader subclasses for backward compatibility.
  *
  * @package WordPress
  * @subpackage Upgrader
  * @since 2.8.0
  */
 
+/** WP_Upgrader_Skin class */
+require_once ABSPATH . 'wp-admin/includes/class-wp-upgrader-skin.php';
+
+/** Plugin_Upgrader_Skin class */
+require_once ABSPATH . 'wp-admin/includes/class-plugin-upgrader-skin.php';
+
+/** Theme_Upgrader_Skin class */
+require_once ABSPATH . 'wp-admin/includes/class-theme-upgrader-skin.php';
+
+/** Bulk_Upgrader_Skin class */
+require_once ABSPATH . 'wp-admin/includes/class-bulk-upgrader-skin.php';
+
+/** Bulk_Plugin_Upgrader_Skin class */
+require_once ABSPATH . 'wp-admin/includes/class-bulk-plugin-upgrader-skin.php';
+
+/** Bulk_Theme_Upgrader_Skin class */
+require_once ABSPATH . 'wp-admin/includes/class-bulk-theme-upgrader-skin.php';
+
+/** Plugin_Installer_Skin class */
+require_once ABSPATH . 'wp-admin/includes/class-plugin-installer-skin.php';
+
+/** Theme_Installer_Skin class */
+require_once ABSPATH . 'wp-admin/includes/class-theme-installer-skin.php';
+
+/** Language_Pack_Upgrader_Skin class */
+require_once ABSPATH . 'wp-admin/includes/class-language-pack-upgrader-skin.php';
+
+/** Automatic_Upgrader_Skin class */
+require_once ABSPATH . 'wp-admin/includes/class-automatic-upgrader-skin.php';
+
+/** WP_Ajax_Upgrader_Skin class */
+require_once ABSPATH . 'wp-admin/includes/class-wp-ajax-upgrader-skin.php';
+
 /**
- * WordPress Upgrader class for Upgrading/Installing a local set of files via the Filesystem Abstraction classes from a Zip file.
+ * Core class used for upgrading/installing a local set of files via
+ * the Filesystem Abstraction classes from a Zip file.
  *
- * @TODO More Detailed docs, for methods as well.
- *
- * @package WordPress
- * @subpackage Upgrader
  * @since 2.8.0
  */
 class WP_Upgrader {
-       var $strings = array();
-       var $skin = null;
-       var $result = array();
 
-       function __construct($skin = null) {
+       /**
+        * The error/notification strings used to update the user on the progress.
+        *
+        * @since 2.8.0
+        * @access public
+        * @var array $strings
+        */
+       public $strings = array();
+
+       /**
+        * The upgrader skin being used.
+        *
+        * @since 2.8.0
+        * @access public
+        * @var Automatic_Upgrader_Skin|WP_Upgrader_Skin $skin
+        */
+       public $skin = null;
+
+       /**
+        * The result of the installation.
+        *
+        * This is set by WP_Upgrader::install_package(), only when the package is installed
+        * successfully. It will then be an array, unless a WP_Error is returned by the
+        * {@see 'upgrader_post_install'} filter. In that case, the WP_Error will be assigned to
+        * it.
+        *
+        * @since 2.8.0
+        * @access public
+        *
+        * @var WP_Error|array $result {
+        *      @type string $source             The full path to the source the files were installed from.
+        *      @type string $source_files       List of all the files in the source directory.
+        *      @type string $destination        The full path to the install destination folder.
+        *      @type string $destination_name   The name of the destination folder, or empty if `$destination`
+        *                                       and `$local_destination` are the same.
+        *      @type string $local_destination  The full local path to the destination folder. This is usually
+        *                                       the same as `$destination`.
+        *      @type string $remote_destination The full remote path to the destination folder
+        *                                       (i.e., from `$wp_filesystem`).
+        *      @type bool   $clear_destination  Whether the destination folder was cleared.
+        * }
+        */
+       public $result = array();
+
+       /**
+        * The total number of updates being performed.
+        *
+        * Set by the bulk update methods.
+        *
+        * @since 3.0.0
+        * @access public
+        * @var int $update_count
+        */
+       public $update_count = 0;
+
+       /**
+        * The current update if multiple updates are being performed.
+        *
+        * Used by the bulk update methods, and incremented for each update.
+        *
+        * @since 3.0.0
+        * @access public
+        * @var int
+        */
+       public $update_current = 0;
+
+       /**
+        * Construct the upgrader with a skin.
+        *
+        * @since 2.8.0
+        * @access public
+        *
+        * @param WP_Upgrader_Skin $skin The upgrader skin to use. Default is a WP_Upgrader_Skin.
+        *                               instance.
+        */
+       public function __construct( $skin = null ) {
                if ( null == $skin )
                        $this->skin = new WP_Upgrader_Skin();
                else
                        $this->skin = $skin;
        }
 
-       function init() {
+       /**
+        * Initialize the upgrader.
+        *
+        * This will set the relationship between the skin being used and this upgrader,
+        * and also add the generic strings to `WP_Upgrader::$strings`.
+        *
+        * @since 2.8.0
+        * @access public
+        */
+       public function init() {
                $this->skin->set_upgrader($this);
                $this->generic_strings();
        }
 
-       function generic_strings() {
-               $this->strings['bad_request'] = __('Invalid Data provided.');
+       /**
+        * Add the generic strings to WP_Upgrader::$strings.
+        *
+        * @since 2.8.0
+        * @access public
+        */
+       public function generic_strings() {
+               $this->strings['bad_request'] = __('Invalid data provided.');
                $this->strings['fs_unavailable'] = __('Could not access filesystem.');
                $this->strings['fs_error'] = __('Filesystem error.');
-               $this->strings['fs_no_root_dir'] = __('Unable to locate WordPress Root directory.');
-               $this->strings['fs_no_content_dir'] = __('Unable to locate WordPress Content directory (wp-content).');
-               $this->strings['fs_no_plugins_dir'] = __('Unable to locate WordPress Plugin directory.');
-               $this->strings['fs_no_themes_dir'] = __('Unable to locate WordPress Theme directory.');
+               $this->strings['fs_no_root_dir'] = __('Unable to locate WordPress root directory.');
+               $this->strings['fs_no_content_dir'] = __('Unable to locate WordPress content directory (wp-content).');
+               $this->strings['fs_no_plugins_dir'] = __('Unable to locate WordPress plugin directory.');
+               $this->strings['fs_no_themes_dir'] = __('Unable to locate WordPress theme directory.');
                /* translators: %s: directory name */
                $this->strings['fs_no_folder'] = __('Unable to locate needed folder (%s).');
 
                $this->strings['download_failed'] = __('Download failed.');
                $this->strings['installing_package'] = __('Installing the latest version&#8230;');
+               $this->strings['no_files'] = __('The package contains no files.');
                $this->strings['folder_exists'] = __('Destination folder already exists.');
                $this->strings['mkdir_failed'] = __('Could not create directory.');
                $this->strings['incompatible_archive'] = __('The package could not be installed.');
+               $this->strings['files_not_writable'] = __( 'The update cannot be installed because we will be unable to copy some files. This is usually due to inconsistent file permissions.' );
 
                $this->strings['maintenance_start'] = __('Enabling Maintenance mode&#8230;');
                $this->strings['maintenance_end'] = __('Disabling Maintenance mode&#8230;');
        }
 
-       function fs_connect( $directories = array() ) {
+       /**
+        * Connect to the filesystem.
+        *
+        * @since 2.8.0
+        * @access public
+        *
+        * @global WP_Filesystem_Base $wp_filesystem Subclass
+        *
+        * @param array $directories                  Optional. A list of directories. If any of these do
+        *                                            not exist, a WP_Error object will be returned.
+        *                                            Default empty array.
+        * @param bool  $allow_relaxed_file_ownership Whether to allow relaxed file ownership.
+        *                                            Default false.
+        * @return bool|WP_Error True if able to connect, false or a WP_Error otherwise.
+        */
+       public function fs_connect( $directories = array(), $allow_relaxed_file_ownership = false ) {
                global $wp_filesystem;
 
-               if ( false === ($credentials = $this->skin->request_filesystem_credentials()) )
+               if ( false === ( $credentials = $this->skin->request_filesystem_credentials( false, $directories[0], $allow_relaxed_file_ownership ) ) ) {
                        return false;
+               }
 
-               if ( ! WP_Filesystem($credentials) ) {
+               if ( ! WP_Filesystem( $credentials, $directories[0], $allow_relaxed_file_ownership ) ) {
                        $error = true;
                        if ( is_object($wp_filesystem) && $wp_filesystem->errors->get_error_code() )
                                $error = $wp_filesystem->errors;
-                       $this->skin->request_filesystem_credentials($error); //Failed to connect, Error and request again
+                       // Failed to connect, Error and request again
+                       $this->skin->request_filesystem_credentials( $error, $directories[0], $allow_relaxed_file_ownership );
                        return false;
                }
 
@@ -92,20 +226,45 @@ class WP_Upgrader {
                                        if ( ! $wp_filesystem->wp_plugins_dir() )
                                                return new WP_Error('fs_no_plugins_dir', $this->strings['fs_no_plugins_dir']);
                                        break;
-                               case WP_CONTENT_DIR . '/themes':
-                                       if ( ! $wp_filesystem->find_folder(WP_CONTENT_DIR . '/themes') )
+                               case get_theme_root():
+                                       if ( ! $wp_filesystem->wp_themes_dir() )
                                                return new WP_Error('fs_no_themes_dir', $this->strings['fs_no_themes_dir']);
                                        break;
                                default:
                                        if ( ! $wp_filesystem->find_folder($dir) )
-                                               return new WP_Error('fs_no_folder', sprintf($this->strings['fs_no_folder'], $dir));
+                                               return new WP_Error( 'fs_no_folder', sprintf( $this->strings['fs_no_folder'], esc_html( basename( $dir ) ) ) );
                                        break;
                        }
                }
                return true;
        } //end fs_connect();
 
-       function download_package($package) {
+       /**
+        * Download a package.
+        *
+        * @since 2.8.0
+        * @access public
+        *
+        * @param string $package The URI of the package. If this is the full path to an
+        *                        existing local file, it will be returned untouched.
+        * @return string|WP_Error The full path to the downloaded package file, or a WP_Error object.
+        */
+       public function download_package( $package ) {
+
+               /**
+                * Filters whether to return the package.
+                *
+                * @since 3.7.0
+                * @access public
+                *
+                * @param bool        $reply   Whether to bail without returning the package.
+                *                             Default false.
+                * @param string      $package The package file name.
+                * @param WP_Upgrader $this    The WP_Upgrader instance.
+                */
+               $reply = apply_filters( 'upgrader_pre_download', false, $package, $this );
+               if ( false !== $reply )
+                       return $reply;
 
                if ( ! preg_match('!^(http|https|ftp)://!i', $package) && file_exists($package) ) //Local file or remote?
                        return $package; //must be a local file..
@@ -123,7 +282,20 @@ class WP_Upgrader {
                return $download_file;
        }
 
-       function unpack_package($package, $delete_package = true) {
+       /**
+        * Unpack a compressed package file.
+        *
+        * @since 2.8.0
+        * @access public
+        *
+        * @global WP_Filesystem_Base $wp_filesystem Subclass
+        *
+        * @param string $package        Full path to the package file.
+        * @param bool   $delete_package Optional. Whether to delete the package file after attempting
+        *                               to unpack it. Default true.
+        * @return string|WP_Error The path to the unpacked contents, or a WP_Error on failure.
+        */
+       public function unpack_package( $package, $delete_package = true ) {
                global $wp_filesystem;
 
                $this->skin->feedback('unpack_package');
@@ -137,15 +309,15 @@ class WP_Upgrader {
                                $wp_filesystem->delete($upgrade_folder . $file['name'], true);
                }
 
-               //We need a working directory
-               $working_dir = $upgrade_folder . basename($package, '.zip');
+               // We need a working directory - Strip off any .tmp or .zip suffixes
+               $working_dir = $upgrade_folder . basename( basename( $package, '.tmp' ), '.zip' );
 
                // Clean up working directory
                if ( $wp_filesystem->is_dir($working_dir) )
                        $wp_filesystem->delete($working_dir, true);
 
                // Unzip package to working directory
-               $result = unzip_file($package, $working_dir); //TODO optimizations, Copy when Move/Rename would suffice?
+               $result = unzip_file( $package, $working_dir );
 
                // Once extracted, delete the package if required.
                if ( $delete_package )
@@ -162,69 +334,219 @@ class WP_Upgrader {
                return $working_dir;
        }
 
-       function install_package($args = array()) {
+       /**
+        * Clears the directory where this item is going to be installed into.
+        *
+        * @since 4.3.0
+        * @access public
+        *
+        * @global WP_Filesystem_Base $wp_filesystem Subclass
+        *
+        * @param string $remote_destination The location on the remote filesystem to be cleared
+        * @return bool|WP_Error True upon success, WP_Error on failure.
+        */
+       public function clear_destination( $remote_destination ) {
                global $wp_filesystem;
-               $defaults = array( 'source' => '', 'destination' => '', //Please always pass these
-                                               'clear_destination' => false, 'clear_working' => false,
-                                               'hook_extra' => array());
 
-               $args = wp_parse_args($args, $defaults);
-               extract($args);
+               if ( ! $wp_filesystem->exists( $remote_destination ) ) {
+                       return true;
+               }
 
-               @set_time_limit( 300 );
+               // Check all files are writable before attempting to clear the destination.
+               $unwritable_files = array();
+
+               $_files = $wp_filesystem->dirlist( $remote_destination, true, true );
+
+               // Flatten the resulting array, iterate using each as we append to the array during iteration.
+               while ( $f = each( $_files ) ) {
+                       $file = $f['value'];
+                       $name = $f['key'];
+
+                       if ( ! isset( $file['files'] ) ) {
+                               continue;
+                       }
+
+                       foreach ( $file['files'] as $filename => $details ) {
+                               $_files[ $name . '/' . $filename ] = $details;
+                       }
+               }
+
+               // Check writability.
+               foreach ( $_files as $filename => $file_details ) {
+                       if ( ! $wp_filesystem->is_writable( $remote_destination . $filename ) ) {
+
+                               // Attempt to alter permissions to allow writes and try again.
+                               $wp_filesystem->chmod( $remote_destination . $filename, ( 'd' == $file_details['type'] ? FS_CHMOD_DIR : FS_CHMOD_FILE ) );
+                               if ( ! $wp_filesystem->is_writable( $remote_destination . $filename ) ) {
+                                       $unwritable_files[] = $filename;
+                               }
+                       }
+               }
+
+               if ( ! empty( $unwritable_files ) ) {
+                       return new WP_Error( 'files_not_writable', $this->strings['files_not_writable'], implode( ', ', $unwritable_files ) );
+               }
+
+               if ( ! $wp_filesystem->delete( $remote_destination, true ) ) {
+                       return new WP_Error( 'remove_old_failed', $this->strings['remove_old_failed'] );
+               }
+
+               return true;
+       }
+
+       /**
+        * Install a package.
+        *
+        * Copies the contents of a package form a source directory, and installs them in
+        * a destination directory. Optionally removes the source. It can also optionally
+        * clear out the destination folder if it already exists.
+        *
+        * @since 2.8.0
+        * @access public
+        *
+        * @global WP_Filesystem_Base $wp_filesystem Subclass
+        * @global array              $wp_theme_directories
+        *
+        * @param array|string $args {
+        *     Optional. Array or string of arguments for installing a package. Default empty array.
+        *
+        *     @type string $source                      Required path to the package source. Default empty.
+        *     @type string $destination                 Required path to a folder to install the package in.
+        *                                               Default empty.
+        *     @type bool   $clear_destination           Whether to delete any files already in the destination
+        *                                               folder. Default false.
+        *     @type bool   $clear_working               Whether to delete the files form the working directory
+        *                                               after copying to the destination. Default false.
+        *     @type bool   $abort_if_destination_exists Whether to abort the installation if
+        *                                               the destination folder already exists. Default true.
+        *     @type array  $hook_extra                  Extra arguments to pass to the filter hooks called by
+        *                                               WP_Upgrader::install_package(). Default empty array.
+        * }
+        *
+        * @return array|WP_Error The result (also stored in `WP_Upgrader::$result`), or a WP_Error on failure.
+        */
+       public function install_package( $args = array() ) {
+               global $wp_filesystem, $wp_theme_directories;
+
+               $defaults = array(
+                       'source' => '', // Please always pass this
+                       'destination' => '', // and this
+                       'clear_destination' => false,
+                       'clear_working' => false,
+                       'abort_if_destination_exists' => true,
+                       'hook_extra' => array()
+               );
 
-               if ( empty($source) || empty($destination) )
-                       return new WP_Error('bad_request', $this->strings['bad_request']);
+               $args = wp_parse_args($args, $defaults);
+
+               // These were previously extract()'d.
+               $source = $args['source'];
+               $destination = $args['destination'];
+               $clear_destination = $args['clear_destination'];
 
-               $this->skin->feedback('installing_package');
+               @set_time_limit( 300 );
 
-               $res = apply_filters('upgrader_pre_install', true, $hook_extra);
-               if ( is_wp_error($res) )
+               if ( empty( $source ) || empty( $destination ) ) {
+                       return new WP_Error( 'bad_request', $this->strings['bad_request'] );
+               }
+               $this->skin->feedback( 'installing_package' );
+
+               /**
+                * Filters the install response before the installation has started.
+                *
+                * Returning a truthy value, or one that could be evaluated as a WP_Error
+                * will effectively short-circuit the installation, returning that value
+                * instead.
+                *
+                * @since 2.8.0
+                *
+                * @param bool|WP_Error $response   Response.
+                * @param array         $hook_extra Extra arguments passed to hooked filters.
+                */
+               $res = apply_filters( 'upgrader_pre_install', true, $args['hook_extra'] );
+
+               if ( is_wp_error( $res ) ) {
                        return $res;
+               }
 
                //Retain the Original source and destinations
-               $remote_source = $source;
+               $remote_source = $args['source'];
                $local_destination = $destination;
 
-               $source_files = array_keys( $wp_filesystem->dirlist($remote_source) );
-               $remote_destination = $wp_filesystem->find_folder($local_destination);
+               $source_files = array_keys( $wp_filesystem->dirlist( $remote_source ) );
+               $remote_destination = $wp_filesystem->find_folder( $local_destination );
 
                //Locate which directory to copy to the new folder, This is based on the actual folder holding the files.
-               if ( 1 == count($source_files) && $wp_filesystem->is_dir( trailingslashit($source) . $source_files[0] . '/') ) //Only one folder? Then we want its contents.
-                       $source = trailingslashit($source) . trailingslashit($source_files[0]);
-               elseif ( count($source_files) == 0 )
-                       return new WP_Error( 'incompatible_archive', $this->strings['incompatible_archive'], __( 'The plugin contains no files.' ) ); //There are no files?
-               else //Its only a single file, The upgrader will use the foldername of this file as the destination folder. foldername is based on zip filename.
-                       $source = trailingslashit($source);
-
-               //Hook ability to change the source file location..
-               $source = apply_filters('upgrader_source_selection', $source, $remote_source, $this);
-               if ( is_wp_error($source) )
+               if ( 1 == count( $source_files ) && $wp_filesystem->is_dir( trailingslashit( $args['source'] ) . $source_files[0] . '/' ) ) { //Only one folder? Then we want its contents.
+                       $source = trailingslashit( $args['source'] ) . trailingslashit( $source_files[0] );
+               } elseif ( count( $source_files ) == 0 ) {
+                       return new WP_Error( 'incompatible_archive_empty', $this->strings['incompatible_archive'], $this->strings['no_files'] ); // There are no files?
+               } else { // It's only a single file, the upgrader will use the folder name of this file as the destination folder. Folder name is based on zip filename.
+                       $source = trailingslashit( $args['source'] );
+               }
+
+               /**
+                * Filters the source file location for the upgrade package.
+                *
+                * @since 2.8.0
+                * @since 4.4.0 The $hook_extra parameter became available.
+                *
+                * @param string      $source        File source location.
+                * @param string      $remote_source Remote file source location.
+                * @param WP_Upgrader $this          WP_Upgrader instance.
+                * @param array       $hook_extra    Extra arguments passed to hooked filters.
+                */
+               $source = apply_filters( 'upgrader_source_selection', $source, $remote_source, $this, $args['hook_extra'] );
+
+               if ( is_wp_error( $source ) ) {
                        return $source;
+               }
+
+               // Has the source location changed? If so, we need a new source_files list.
+               if ( $source !== $remote_source ) {
+                       $source_files = array_keys( $wp_filesystem->dirlist( $source ) );
+               }
+
+               /*
+                * Protection against deleting files in any important base directories.
+                * Theme_Upgrader & Plugin_Upgrader also trigger this, as they pass the
+                * destination directory (WP_PLUGIN_DIR / wp-content/themes) intending
+                * to copy the directory into the directory, whilst they pass the source
+                * as the actual files to copy.
+                */
+               $protected_directories = array( ABSPATH, WP_CONTENT_DIR, WP_PLUGIN_DIR, WP_CONTENT_DIR . '/themes' );
 
-               //Has the source location changed? If so, we need a new source_files list.
-               if ( $source !== $remote_source )
-                       $source_files = array_keys( $wp_filesystem->dirlist($source) );
+               if ( is_array( $wp_theme_directories ) ) {
+                       $protected_directories = array_merge( $protected_directories, $wp_theme_directories );
+               }
 
-               //Protection against deleting files in any important base directories.
-               if ( in_array( $destination, array(ABSPATH, WP_CONTENT_DIR, WP_PLUGIN_DIR, WP_CONTENT_DIR . '/themes') ) ) {
-                       $remote_destination = trailingslashit($remote_destination) . trailingslashit(basename($source));
-                       $destination = trailingslashit($destination) . trailingslashit(basename($source));
+               if ( in_array( $destination, $protected_directories ) ) {
+                       $remote_destination = trailingslashit( $remote_destination ) . trailingslashit( basename( $source ) );
+                       $destination = trailingslashit( $destination ) . trailingslashit( basename( $source ) );
                }
 
                if ( $clear_destination ) {
-                       //We're going to clear the destination if there's something there
+                       // We're going to clear the destination if there's something there.
                        $this->skin->feedback('remove_old');
-                       $removed = true;
-                       if ( $wp_filesystem->exists($remote_destination) )
-                               $removed = $wp_filesystem->delete($remote_destination, true);
-                       $removed = apply_filters('upgrader_clear_destination', $removed, $local_destination, $remote_destination, $hook_extra);
 
-                       if ( is_wp_error($removed) )
+                       $removed = $this->clear_destination( $remote_destination );
+
+                       /**
+                        * Filters whether the upgrader cleared the destination.
+                        *
+                        * @since 2.8.0
+                        *
+                        * @param mixed  $removed            Whether the destination was cleared. true on success, WP_Error on failure
+                        * @param string $local_destination  The local package destination.
+                        * @param string $remote_destination The remote package destination.
+                        * @param array  $hook_extra         Extra arguments passed to hooked filters.
+                        */
+                       $removed = apply_filters( 'upgrader_clear_destination', $removed, $local_destination, $remote_destination, $args['hook_extra'] );
+
+                       if ( is_wp_error( $removed ) ) {
                                return $removed;
-                       else if ( ! $removed )
-                               return new WP_Error('remove_old_failed', $this->strings['remove_old_failed']);
-               } elseif ( $wp_filesystem->exists($remote_destination) ) {
+                       }
+               } elseif ( $args['abort_if_destination_exists'] && $wp_filesystem->exists($remote_destination) ) {
                        //If we're not clearing the destination folder and something exists there already, Bail.
                        //But first check to see if there are actually any files in the folder.
                        $_files = $wp_filesystem->dirlist($remote_destination);
@@ -235,29 +557,43 @@ class WP_Upgrader {
                }
 
                //Create destination if needed
-               if ( !$wp_filesystem->exists($remote_destination) )
-                       if ( !$wp_filesystem->mkdir($remote_destination, FS_CHMOD_DIR) )
-                               return new WP_Error('mkdir_failed', $this->strings['mkdir_failed'], $remote_destination);
-
+               if ( ! $wp_filesystem->exists( $remote_destination ) ) {
+                       if ( ! $wp_filesystem->mkdir( $remote_destination, FS_CHMOD_DIR ) ) {
+                               return new WP_Error( 'mkdir_failed_destination', $this->strings['mkdir_failed'], $remote_destination );
+                       }
+               }
                // Copy new version of item into place.
                $result = copy_dir($source, $remote_destination);
                if ( is_wp_error($result) ) {
-                       if ( $clear_working )
-                               $wp_filesystem->delete($remote_source, true);
+                       if ( $args['clear_working'] ) {
+                               $wp_filesystem->delete( $remote_source, true );
+                       }
                        return $result;
                }
 
                //Clear the Working folder?
-               if ( $clear_working )
-                       $wp_filesystem->delete($remote_source, true);
+               if ( $args['clear_working'] ) {
+                       $wp_filesystem->delete( $remote_source, true );
+               }
 
                $destination_name = basename( str_replace($local_destination, '', $destination) );
-               if ( '.' == $destination_name )
+               if ( '.' == $destination_name ) {
                        $destination_name = '';
+               }
 
-               $this->result = compact('local_source', 'source', 'source_name', 'source_files', 'destination', 'destination_name', 'local_destination', 'remote_destination', 'clear_destination', 'delete_source_dir');
+               $this->result = compact( 'source', 'source_files', 'destination', 'destination_name', 'local_destination', 'remote_destination', 'clear_destination' );
+
+               /**
+                * Filters the install response after the installation has finished.
+                *
+                * @since 2.8.0
+                *
+                * @param bool  $response   Install response.
+                * @param array $hook_extra Extra arguments passed to hooked filters.
+                * @param array $result     Installation result data.
+                */
+               $res = apply_filters( 'upgrader_post_install', true, $args['hook_extra'], $this->result );
 
-               $res = apply_filters('upgrader_post_install', true, $hook_extra, $this->result);
                if ( is_wp_error($res) ) {
                        $this->result = $res;
                        return $res;
@@ -267,77 +603,212 @@ class WP_Upgrader {
                return $this->result;
        }
 
-       function run($options) {
-
-               $defaults = array(      'package' => '', //Please always pass this.
-                                                       'destination' => '', //And this
-                                                       'clear_destination' => false,
-                                                       'clear_working' => true,
-                                                       'is_multi' => false,
-                                                       'hook_extra' => array() //Pass any extra $hook_extra args here, this will be passed to any hooked filters.
-                                               );
+       /**
+        * Run an upgrade/install.
+        *
+        * Attempts to download the package (if it is not a local file), unpack it, and
+        * install it in the destination folder.
+        *
+        * @since 2.8.0
+        * @access public
+        *
+        * @param array $options {
+        *     Array or string of arguments for upgrading/installing a package.
+        *
+        *     @type string $package                     The full path or URI of the package to install.
+        *                                               Default empty.
+        *     @type string $destination                 The full path to the destination folder.
+        *                                               Default empty.
+        *     @type bool   $clear_destination           Whether to delete any files already in the
+        *                                               destination folder. Default false.
+        *     @type bool   $clear_working               Whether to delete the files form the working
+        *                                               directory after copying to the destination.
+        *                                               Default false.
+        *     @type bool   $abort_if_destination_exists Whether to abort the installation if the destination
+        *                                               folder already exists. When true, `$clear_destination`
+        *                                               should be false. Default true.
+        *     @type bool   $is_multi                    Whether this run is one of multiple upgrade/install
+        *                                               actions being performed in bulk. When true, the skin
+        *                                               WP_Upgrader::header() and WP_Upgrader::footer()
+        *                                               aren't called. Default false.
+        *     @type array  $hook_extra                  Extra arguments to pass to the filter hooks called by
+        *                                               WP_Upgrader::run().
+        * }
+        * @return array|false|WP_error The result from self::install_package() on success, otherwise a WP_Error,
+        *                              or false if unable to connect to the filesystem.
+        */
+       public function run( $options ) {
+
+               $defaults = array(
+                       'package' => '', // Please always pass this.
+                       'destination' => '', // And this
+                       'clear_destination' => false,
+                       'abort_if_destination_exists' => true, // Abort if the Destination directory exists, Pass clear_destination as false please
+                       'clear_working' => true,
+                       'is_multi' => false,
+                       'hook_extra' => array() // Pass any extra $hook_extra args here, this will be passed to any hooked filters.
+               );
 
-               $options = wp_parse_args($options, $defaults);
-               extract($options);
+               $options = wp_parse_args( $options, $defaults );
+
+               /**
+                * Filters the package options before running an update.
+                *
+                * See also {@see 'upgrader_process_complete'}.
+                *
+                * @since 4.3.0
+                *
+                * @param array $options {
+                *     Options used by the upgrader.
+                *
+                *     @type string $package                     Package for update.
+                *     @type string $destination                 Update location.
+                *     @type bool   $clear_destination           Clear the destination resource.
+                *     @type bool   $clear_working               Clear the working resource.
+                *     @type bool   $abort_if_destination_exists Abort if the Destination directory exists.
+                *     @type bool   $is_multi                    Whether the upgrader is running multiple times.
+                *     @type array  $hook_extra {
+                *         Extra hook arguments.
+                *
+                *         @type string $action               Type of action. Default 'update'.
+                *         @type string $type                 Type of update process. Accepts 'plugin', 'theme', or 'core'.
+                *         @type bool   $bulk                 Whether the update process is a bulk update. Default true.
+                *         @type string $plugin               The base plugin path from the plugins directory.
+                *         @type string $theme                The stylesheet or template name of the theme.
+                *         @type string $language_update_type The language pack update type. Accepts 'plugin', 'theme',
+                *                                            or 'core'.
+                *         @type object $language_update      The language pack update offer.
+                *     }
+                * }
+                */
+               $options = apply_filters( 'upgrader_package_options', $options );
+
+               if ( ! $options['is_multi'] ) { // call $this->header separately if running multiple times
+                       $this->skin->header();
+               }
 
-               //Connect to the Filesystem first.
-               $res = $this->fs_connect( array(WP_CONTENT_DIR, $destination) );
-               if ( ! $res ) //Mainly for non-connected filesystem.
+               // Connect to the Filesystem first.
+               $res = $this->fs_connect( array( WP_CONTENT_DIR, $options['destination'] ) );
+               // Mainly for non-connected filesystem.
+               if ( ! $res ) {
+                       if ( ! $options['is_multi'] ) {
+                               $this->skin->footer();
+                       }
                        return false;
+               }
+
+               $this->skin->before();
 
                if ( is_wp_error($res) ) {
                        $this->skin->error($res);
+                       $this->skin->after();
+                       if ( ! $options['is_multi'] ) {
+                               $this->skin->footer();
+                       }
                        return $res;
                }
 
-               if ( !$is_multi ) // call $this->header separately if running multiple times
-                       $this->skin->header();
-
-               $this->skin->before();
-
-               //Download the package (Note, This just returns the filename of the file if the package is a local file)
-               $download = $this->download_package( $package );
+               /*
+                * Download the package (Note, This just returns the filename
+                * of the file if the package is a local file)
+                */
+               $download = $this->download_package( $options['package'] );
                if ( is_wp_error($download) ) {
                        $this->skin->error($download);
                        $this->skin->after();
+                       if ( ! $options['is_multi'] ) {
+                               $this->skin->footer();
+                       }
                        return $download;
                }
 
-               $delete_package = ($download != $package); // Do not delete a "local" file
+               $delete_package = ( $download != $options['package'] ); // Do not delete a "local" file
 
-               //Unzips the file into a temporary directory
+               // Unzips the file into a temporary directory.
                $working_dir = $this->unpack_package( $download, $delete_package );
                if ( is_wp_error($working_dir) ) {
                        $this->skin->error($working_dir);
                        $this->skin->after();
+                       if ( ! $options['is_multi'] ) {
+                               $this->skin->footer();
+                       }
                        return $working_dir;
                }
 
-               //With the given options, this installs it to the destination directory.
+               // With the given options, this installs it to the destination directory.
                $result = $this->install_package( array(
-                                                                                       'source' => $working_dir,
-                                                                                       'destination' => $destination,
-                                                                                       'clear_destination' => $clear_destination,
-                                                                                       'clear_working' => $clear_working,
-                                                                                       'hook_extra' => $hook_extra
-                                                                               ) );
+                       'source' => $working_dir,
+                       'destination' => $options['destination'],
+                       'clear_destination' => $options['clear_destination'],
+                       'abort_if_destination_exists' => $options['abort_if_destination_exists'],
+                       'clear_working' => $options['clear_working'],
+                       'hook_extra' => $options['hook_extra']
+               ) );
+
                $this->skin->set_result($result);
                if ( is_wp_error($result) ) {
                        $this->skin->error($result);
                        $this->skin->feedback('process_failed');
                } else {
-                       //Install Succeeded
+                       // Install succeeded.
                        $this->skin->feedback('process_success');
                }
+
                $this->skin->after();
 
-               if ( !$is_multi )
+               if ( ! $options['is_multi'] ) {
+
+                       /**
+                        * Fires when the upgrader process is complete.
+                        *
+                        * See also {@see 'upgrader_package_options'}.
+                        *
+                        * @since 3.6.0
+                        * @since 3.7.0 Added to WP_Upgrader::run().
+                        * @since 4.6.0 `$translations` was added as a possible argument to `$hook_extra`.
+                        *
+                        * @param WP_Upgrader $this WP_Upgrader instance. In other contexts, $this, might be a
+                        *                          Theme_Upgrader, Plugin_Upgrader, Core_Upgrade, or Language_Pack_Upgrader instance.
+                        * @param array       $hook_extra {
+                        *     Array of bulk item update data.
+                        *
+                        *     @type string $action       Type of action. Default 'update'.
+                        *     @type string $type         Type of update process. Accepts 'plugin', 'theme', 'translation', or 'core'.
+                        *     @type bool   $bulk         Whether the update process is a bulk update. Default true.
+                        *     @type array  $plugins      Array of the basename paths of the plugins' main files.
+                        *     @type array  $themes       The theme slugs.
+                        *     @type array  $translations {
+                        *         Array of translations update data.
+                        *
+                        *         @type string $language The locale the translation is for.
+                        *         @type string $type     Type of translation. Accepts 'plugin', 'theme', or 'core'.
+                        *         @type string $slug     Text domain the translation is for. The slug of a theme/plugin or
+                        *                                'default' for core translations.
+                        *         @type string $version  The version of a theme, plugin, or core.
+                        *     }
+                        * }
+                        */
+                       do_action( 'upgrader_process_complete', $this, $options['hook_extra'] );
+
                        $this->skin->footer();
+               }
 
                return $result;
        }
 
-       function maintenance_mode($enable = false) {
+       /**
+        * Toggle maintenance mode for the site.
+        *
+        * Creates/deletes the maintenance file to enable/disable maintenance mode.
+        *
+        * @since 2.8.0
+        * @access public
+        *
+        * @global WP_Filesystem_Base $wp_filesystem Subclass
+        *
+        * @param bool $enable True to enable maintenance mode, false to disable.
+        */
+       public function maintenance_mode( $enable = false ) {
                global $wp_filesystem;
                $file = $wp_filesystem->abspath() . '.maintenance';
                if ( $enable ) {
@@ -346,1334 +817,91 @@ class WP_Upgrader {
                        $maintenance_string = '<?php $upgrading = ' . time() . '; ?>';
                        $wp_filesystem->delete($file);
                        $wp_filesystem->put_contents($file, $maintenance_string, FS_CHMOD_FILE);
-               } else if ( !$enable && $wp_filesystem->exists($file) ) {
+               } elseif ( ! $enable && $wp_filesystem->exists( $file ) ) {
                        $this->skin->feedback('maintenance_end');
                        $wp_filesystem->delete($file);
                }
        }
 
-}
-
-/**
- * Plugin Upgrader class for WordPress Plugins, It is designed to upgrade/install plugins from a local zip, remote zip URL, or uploaded zip file.
- *
- * @TODO More Detailed docs, for methods as well.
- *
- * @package WordPress
- * @subpackage Upgrader
- * @since 2.8.0
- */
-class Plugin_Upgrader extends WP_Upgrader {
-
-       var $result;
-       var $bulk = false;
-       var $show_before = '';
-
-       function upgrade_strings() {
-               $this->strings['up_to_date'] = __('The plugin is at the latest version.');
-               $this->strings['no_package'] = __('Update package not available.');
-               $this->strings['downloading_package'] = __('Downloading update from <span class="code">%s</span>&#8230;');
-               $this->strings['unpack_package'] = __('Unpacking the update&#8230;');
-               $this->strings['remove_old'] = __('Removing the old version of the plugin&#8230;');
-               $this->strings['remove_old_failed'] = __('Could not remove the old plugin.');
-               $this->strings['process_failed'] = __('Plugin update failed.');
-               $this->strings['process_success'] = __('Plugin updated successfully.');
-       }
-
-       function install_strings() {
-               $this->strings['no_package'] = __('Install package not available.');
-               $this->strings['downloading_package'] = __('Downloading install package from <span class="code">%s</span>&#8230;');
-               $this->strings['unpack_package'] = __('Unpacking the package&#8230;');
-               $this->strings['installing_package'] = __('Installing the plugin&#8230;');
-               $this->strings['process_failed'] = __('Plugin install failed.');
-               $this->strings['process_success'] = __('Plugin installed successfully.');
-       }
-
-       function install($package) {
-
-               $this->init();
-               $this->install_strings();
-
-               add_filter('upgrader_source_selection', array(&$this, 'check_package') );
-
-               $this->run(array(
-                                       'package' => $package,
-                                       'destination' => WP_PLUGIN_DIR,
-                                       'clear_destination' => false, //Do not overwrite files.
-                                       'clear_working' => true,
-                                       'hook_extra' => array()
-                                       ));
-
-               remove_filter('upgrader_source_selection', array(&$this, 'check_package') );
-
-               if ( ! $this->result || is_wp_error($this->result) )
-                       return $this->result;
-
-               // Force refresh of plugin update information
-               delete_site_transient('update_plugins');
-               wp_cache_delete( 'plugins', 'plugins' );
-
-               return true;
-       }
-
-       function upgrade($plugin) {
-
-               $this->init();
-               $this->upgrade_strings();
-
-               $current = get_site_transient( 'update_plugins' );
-               if ( !isset( $current->response[ $plugin ] ) ) {
-                       $this->skin->before();
-                       $this->skin->set_result(false);
-                       $this->skin->error('up_to_date');
-                       $this->skin->after();
-                       return false;
+       /**
+        * Creates a lock using WordPress options.
+        *
+        * @since 4.5.0
+        * @access public
+        * @static
+        *
+        * @param string $lock_name       The name of this unique lock.
+        * @param int    $release_timeout Optional. The duration in seconds to respect an existing lock.
+        *                                Default: 1 hour.
+        * @return bool False if a lock couldn't be created or if the lock is no longer valid. True otherwise.
+        */
+       public static function create_lock( $lock_name, $release_timeout = null ) {
+               global $wpdb;
+               if ( ! $release_timeout ) {
+                       $release_timeout = HOUR_IN_SECONDS;
                }
+               $lock_option = $lock_name . '.lock';
 
-               // Get the URL to the zip file
-               $r = $current->response[ $plugin ];
-
-               add_filter('upgrader_pre_install', array(&$this, 'deactivate_plugin_before_upgrade'), 10, 2);
-               add_filter('upgrader_clear_destination', array(&$this, 'delete_old_plugin'), 10, 4);
-               //'source_selection' => array(&$this, 'source_selection'), //there's a trac ticket to move up the directory for zip's which are made a bit differently, useful for non-.org plugins.
-
-               $this->run(array(
-                                       'package' => $r->package,
-                                       'destination' => WP_PLUGIN_DIR,
-                                       'clear_destination' => true,
-                                       'clear_working' => true,
-                                       'hook_extra' => array(
-                                                               'plugin' => $plugin
-                                       )
-                               ));
-
-               // Cleanup our hooks, in case something else does a upgrade on this connection.
-               remove_filter('upgrader_pre_install', array(&$this, 'deactivate_plugin_before_upgrade'));
-               remove_filter('upgrader_clear_destination', array(&$this, 'delete_old_plugin'));
-
-               if ( ! $this->result || is_wp_error($this->result) )
-                       return $this->result;
-
-               // Force refresh of plugin update information
-               delete_site_transient('update_plugins');
-               wp_cache_delete( 'plugins', 'plugins' );
-       }
-
-       function bulk_upgrade($plugins) {
-
-               $this->init();
-               $this->bulk = true;
-               $this->upgrade_strings();
-
-               $current = get_site_transient( 'update_plugins' );
-
-               add_filter('upgrader_clear_destination', array(&$this, 'delete_old_plugin'), 10, 4);
+               // Try to lock.
+               $lock_result = $wpdb->query( $wpdb->prepare( "INSERT IGNORE INTO `$wpdb->options` ( `option_name`, `option_value`, `autoload` ) VALUES (%s, %s, 'no') /* LOCK */", $lock_option, time() ) );
 
-               $this->skin->header();
+               if ( ! $lock_result ) {
+                       $lock_result = get_option( $lock_option );
 
-               // Connect to the Filesystem first.
-               $res = $this->fs_connect( array(WP_CONTENT_DIR, WP_PLUGIN_DIR) );
-               if ( ! $res ) {
-                       $this->skin->footer();
-                       return false;
-               }
-
-               $this->skin->bulk_header();
-
-               // Only start maintenance mode if running in Multisite OR the plugin is in use
-               $maintenance = is_multisite(); // @TODO: This should only kick in for individual sites if at all possible.
-               foreach ( $plugins as $plugin )
-                       $maintenance = $maintenance || (is_plugin_active($plugin) && isset($current->response[ $plugin ]) ); // Only activate Maintenance mode if a plugin is active AND has an update available
-               if ( $maintenance )
-                       $this->maintenance_mode(true);
-
-               $results = array();
-
-               $this->update_count = count($plugins);
-               $this->update_current = 0;
-               foreach ( $plugins as $plugin ) {
-                       $this->update_current++;
-                       $this->skin->plugin_info = get_plugin_data( WP_PLUGIN_DIR . '/' . $plugin, false, true);
-
-                       if ( !isset( $current->response[ $plugin ] ) ) {
-                               $this->skin->set_result(false);
-                               $this->skin->before();
-                               $this->skin->error('up_to_date');
-                               $this->skin->after();
-                               $results[$plugin] = false;
-                               continue;
+                       // If a lock couldn't be created, and there isn't a lock, bail.
+                       if ( ! $lock_result ) {
+                               return false;
                        }
 
-                       // Get the URL to the zip file
-                       $r = $current->response[ $plugin ];
-
-                       $this->skin->plugin_active = is_plugin_active($plugin);
-
-                       $result = $this->run(array(
-                                               'package' => $r->package,
-                                               'destination' => WP_PLUGIN_DIR,
-                                               'clear_destination' => true,
-                                               'clear_working' => true,
-                                               'is_multi' => true,
-                                               'hook_extra' => array(
-                                                                       'plugin' => $plugin
-                                               )
-                                       ));
-
-                       $results[$plugin] = $this->result;
-
-                       // Prevent credentials auth screen from displaying multiple times
-                       if ( false === $result )
-                               break;
-               } //end foreach $plugins
-
-               $this->maintenance_mode(false);
-
-               $this->skin->bulk_footer();
-
-               $this->skin->footer();
-
-               // Cleanup our hooks, in case something else does a upgrade on this connection.
-               remove_filter('upgrader_clear_destination', array(&$this, 'delete_old_plugin'));
-
-               // Force refresh of plugin update information
-               delete_site_transient('update_plugins');
-               wp_cache_delete( 'plugins', 'plugins' );
-
-               return $results;
-       }
-
-       function check_package($source) {
-               global $wp_filesystem;
-
-               if ( is_wp_error($source) )
-                       return $source;
-
-               $working_directory = str_replace( $wp_filesystem->wp_content_dir(), trailingslashit(WP_CONTENT_DIR), $source);
-               if ( ! is_dir($working_directory) ) // Sanity check, if the above fails, lets not prevent installation.
-                       return $source;
-
-               // Check the folder contains at least 1 valid plugin.
-               $plugins_found = false;
-               foreach ( glob( $working_directory . '*.php' ) as $file ) {
-                       $info = get_plugin_data($file, false, false);
-                       if ( !empty( $info['Name'] ) ) {
-                               $plugins_found = true;
-                               break;
+                       // Check to see if the lock is still valid. If not, bail.
+                       if ( $lock_result > ( time() - $release_timeout ) ) {
+                               return false;
                        }
-               }
-
-               if ( ! $plugins_found )
-                       return new WP_Error( 'incompatible_archive', $this->strings['incompatible_archive'], __('No valid plugins were found.') );
-
-               return $source;
-       }
-
-       //return plugin info.
-       function plugin_info() {
-               if ( ! is_array($this->result) )
-                       return false;
-               if ( empty($this->result['destination_name']) )
-                       return false;
-
-               $plugin = get_plugins('/' . $this->result['destination_name']); //Ensure to pass with leading slash
-               if ( empty($plugin) )
-                       return false;
-
-               $pluginfiles = array_keys($plugin); //Assume the requested plugin is the first in the list
-
-               return $this->result['destination_name'] . '/' . $pluginfiles[0];
-       }
-
-       //Hooked to pre_install
-       function deactivate_plugin_before_upgrade($return, $plugin) {
-
-               if ( is_wp_error($return) ) //Bypass.
-                       return $return;
-
-               $plugin = isset($plugin['plugin']) ? $plugin['plugin'] : '';
-               if ( empty($plugin) )
-                       return new WP_Error('bad_request', $this->strings['bad_request']);
-
-               if ( is_plugin_active($plugin) ) {
-                       //Deactivate the plugin silently, Prevent deactivation hooks from running.
-                       deactivate_plugins($plugin, true);
-               }
-       }
-
-       //Hooked to upgrade_clear_destination
-       function delete_old_plugin($removed, $local_destination, $remote_destination, $plugin) {
-               global $wp_filesystem;
-
-               if ( is_wp_error($removed) )
-                       return $removed; //Pass errors through.
-
-               $plugin = isset($plugin['plugin']) ? $plugin['plugin'] : '';
-               if ( empty($plugin) )
-                       return new WP_Error('bad_request', $this->strings['bad_request']);
-
-               $plugins_dir = $wp_filesystem->wp_plugins_dir();
-               $this_plugin_dir = trailingslashit( dirname($plugins_dir . $plugin) );
-
-               if ( ! $wp_filesystem->exists($this_plugin_dir) ) //If its already vanished.
-                       return $removed;
-
-               // If plugin is in its own directory, recursively delete the directory.
-               if ( strpos($plugin, '/') && $this_plugin_dir != $plugins_dir ) //base check on if plugin includes directory separator AND that its not the root plugin folder
-                       $deleted = $wp_filesystem->delete($this_plugin_dir, true);
-               else
-                       $deleted = $wp_filesystem->delete($plugins_dir . $plugin);
-
-               if ( ! $deleted )
-                       return new WP_Error('remove_old_failed', $this->strings['remove_old_failed']);
-
-               return true;
-       }
-}
-
-/**
- * Theme Upgrader class for WordPress Themes, It is designed to upgrade/install themes from a local zip, remote zip URL, or uploaded zip file.
- *
- * @TODO More Detailed docs, for methods as well.
- *
- * @package WordPress
- * @subpackage Upgrader
- * @since 2.8.0
- */
-class Theme_Upgrader extends WP_Upgrader {
-
-       var $result;
-       var $bulk = false;
-
-       function upgrade_strings() {
-               $this->strings['up_to_date'] = __('The theme is at the latest version.');
-               $this->strings['no_package'] = __('Update package not available.');
-               $this->strings['downloading_package'] = __('Downloading update from <span class="code">%s</span>&#8230;');
-               $this->strings['unpack_package'] = __('Unpacking the update&#8230;');
-               $this->strings['remove_old'] = __('Removing the old version of the theme&#8230;');
-               $this->strings['remove_old_failed'] = __('Could not remove the old theme.');
-               $this->strings['process_failed'] = __('Theme update failed.');
-               $this->strings['process_success'] = __('Theme updated successfully.');
-       }
-
-       function install_strings() {
-               $this->strings['no_package'] = __('Install package not available.');
-               $this->strings['downloading_package'] = __('Downloading install package from <span class="code">%s</span>&#8230;');
-               $this->strings['unpack_package'] = __('Unpacking the package&#8230;');
-               $this->strings['installing_package'] = __('Installing the theme&#8230;');
-               $this->strings['process_failed'] = __('Theme install failed.');
-               $this->strings['process_success'] = __('Theme installed successfully.');
-               /* translators: 1: theme name, 2: version */
-               $this->strings['process_success_specific'] = __('Successfully installed the theme <strong>%1$s %2$s</strong>.');
-               $this->strings['parent_theme_search'] = __('This theme requires a parent theme. Checking if it is installed&#8230;');
-               /* translators: 1: theme name, 2: version */
-               $this->strings['parent_theme_prepare_install'] = __('Preparing to install <strong>%1$s %2$s</strong>&#8230;');
-               /* translators: 1: theme name, 2: version */
-               $this->strings['parent_theme_currently_installed'] = __('The parent theme, <strong>%1$s %2$s</strong>, is currently installed.');
-               /* translators: 1: theme name, 2: version */
-               $this->strings['parent_theme_install_success'] = __('Successfully installed the parent theme, <strong>%1$s %2$s</strong>.');
-               $this->strings['parent_theme_not_found'] = __('<strong>The parent theme could not be found.</strong> You will need to install the parent theme, <strong>%s</strong>, before you can use this child theme.');
-       }
-
-       function check_parent_theme_filter($install_result, $hook_extra, $child_result) {
-               // Check to see if we need to install a parent theme
-               $theme_info = $this->theme_info();
-
-               if ( ! $theme_info->parent() )
-                       return $install_result;
-
-               $this->skin->feedback( 'parent_theme_search' );
-
-               if ( ! $theme_info->parent()->errors() ) {
-                       $this->skin->feedback( 'parent_theme_currently_installed', $theme_info->parent()->display('Name'), $theme_info->parent()->display('Version') );
-                       // We already have the theme, fall through.
-                       return $install_result;
-               }
-
-               // We don't have the parent theme, lets install it
-               $api = themes_api('theme_information', array('slug' => $theme_info->get('Template'), 'fields' => array('sections' => false, 'tags' => false) ) ); //Save on a bit of bandwidth.
-
-               if ( ! $api || is_wp_error($api) ) {
-                       $this->skin->feedback( 'parent_theme_not_found', $theme_info->get('Template') );
-                       // Don't show activate or preview actions after install
-                       add_filter('install_theme_complete_actions', array(&$this, 'hide_activate_preview_actions') );
-                       return $install_result;
-               }
-
-               // Backup required data we're going to override:
-               $child_api = $this->skin->api;
-               $child_success_message = $this->strings['process_success'];
-
-               // Override them
-               $this->skin->api = $api;
-               $this->strings['process_success_specific'] = $this->strings['parent_theme_install_success'];//, $api->name, $api->version);
-
-               $this->skin->feedback('parent_theme_prepare_install', $api->name, $api->version);
 
-               add_filter('install_theme_complete_actions', '__return_false', 999); // Don't show any actions after installing the theme.
+                       // There must exist an expired lock, clear it and re-gain it.
+                       WP_Upgrader::release_lock( $lock_name );
 
-               // Install the parent theme
-               $parent_result = $this->run( array(
-                       'package' => $api->download_link,
-                       'destination' => WP_CONTENT_DIR . '/themes',
-                       'clear_destination' => false, //Do not overwrite files.
-                       'clear_working' => true
-               ) );
-
-               if ( is_wp_error($parent_result) )
-                       add_filter('install_theme_complete_actions', array(&$this, 'hide_activate_preview_actions') );
-
-               // Start cleaning up after the parents installation
-               remove_filter('install_theme_complete_actions', '__return_false', 999);
-
-               // Reset child's result and data
-               $this->result = $child_result;
-               $this->skin->api = $child_api;
-               $this->strings['process_success'] = $child_success_message;
-
-               return $install_result;
-       }
-
-       function hide_activate_preview_actions($actions) {
-               unset($actions['activate'], $actions['preview']);
-               return $actions;
-       }
-
-       function install($package) {
-
-               $this->init();
-               $this->install_strings();
-
-               add_filter('upgrader_source_selection', array(&$this, 'check_package') );
-               add_filter('upgrader_post_install', array(&$this, 'check_parent_theme_filter'), 10, 3);
-
-               $options = array(
-                                               'package' => $package,
-                                               'destination' => WP_CONTENT_DIR . '/themes',
-                                               'clear_destination' => false, //Do not overwrite files.
-                                               'clear_working' => true
-                                               );
-
-               $this->run($options);
-
-               remove_filter('upgrader_source_selection', array(&$this, 'check_package') );
-               remove_filter('upgrader_post_install', array(&$this, 'check_parent_theme_filter'), 10, 3);
-
-               if ( ! $this->result || is_wp_error($this->result) )
-                       return $this->result;
-
-               // Force refresh of theme update information
-               delete_site_transient('update_themes');
-               search_theme_directories( true );
-               foreach ( wp_get_themes() as $theme )
-                       $theme->cache_delete();
-
-               return true;
-       }
-
-       function upgrade($theme) {
-
-               $this->init();
-               $this->upgrade_strings();
-
-               // Is an update available?
-               $current = get_site_transient( 'update_themes' );
-               if ( !isset( $current->response[ $theme ] ) ) {
-                       $this->skin->before();
-                       $this->skin->set_result(false);
-                       $this->skin->error('up_to_date');
-                       $this->skin->after();
-                       return false;
+                       return WP_Upgrader::create_lock( $lock_name, $release_timeout );
                }
 
-               $r = $current->response[ $theme ];
-
-               add_filter('upgrader_pre_install', array(&$this, 'current_before'), 10, 2);
-               add_filter('upgrader_post_install', array(&$this, 'current_after'), 10, 2);
-               add_filter('upgrader_clear_destination', array(&$this, 'delete_old_theme'), 10, 4);
-
-               $options = array(
-                                               'package' => $r['package'],
-                                               'destination' => WP_CONTENT_DIR . '/themes',
-                                               'clear_destination' => true,
-                                               'clear_working' => true,
-                                               'hook_extra' => array(
-                                                                                       'theme' => $theme
-                                                                                       )
-                                               );
-
-               $this->run($options);
-
-               remove_filter('upgrader_pre_install', array(&$this, 'current_before'), 10, 2);
-               remove_filter('upgrader_post_install', array(&$this, 'current_after'), 10, 2);
-               remove_filter('upgrader_clear_destination', array(&$this, 'delete_old_theme'), 10, 4);
-
-               if ( ! $this->result || is_wp_error($this->result) )
-                       return $this->result;
-
-               // Force refresh of theme update information
-               delete_site_transient('update_themes');
-               search_theme_directories( true );
-               foreach ( wp_get_themes() as $theme )
-                       $theme->cache_delete();
+               // Update the lock, as by this point we've definitely got a lock, just need to fire the actions.
+               update_option( $lock_option, time() );
 
                return true;
        }
 
-       function bulk_upgrade($themes) {
-
-               $this->init();
-               $this->bulk = true;
-               $this->upgrade_strings();
-
-               $current = get_site_transient( 'update_themes' );
-
-               add_filter('upgrader_pre_install', array(&$this, 'current_before'), 10, 2);
-               add_filter('upgrader_post_install', array(&$this, 'current_after'), 10, 2);
-               add_filter('upgrader_clear_destination', array(&$this, 'delete_old_theme'), 10, 4);
-
-               $this->skin->header();
-
-               // Connect to the Filesystem first.
-               $res = $this->fs_connect( array(WP_CONTENT_DIR) );
-               if ( ! $res ) {
-                       $this->skin->footer();
-                       return false;
-               }
-
-               $this->skin->bulk_header();
-
-               // Only start maintenance mode if running in Multisite OR the theme is in use
-               $maintenance = is_multisite(); // @TODO: This should only kick in for individual sites if at all possible.
-               foreach ( $themes as $theme )
-                       $maintenance = $maintenance || $theme == get_stylesheet() || $theme == get_template();
-               if ( $maintenance )
-                       $this->maintenance_mode(true);
-
-               $results = array();
-
-               $this->update_count = count($themes);
-               $this->update_current = 0;
-               foreach ( $themes as $theme ) {
-                       $this->update_current++;
-
-                       if ( !isset( $current->response[ $theme ] ) ) {
-                               $this->skin->set_result(false);
-                               $this->skin->before();
-                               $this->skin->error('up_to_date');
-                               $this->skin->after();
-                               $results[$theme] = false;
-                               continue;
-                       }
-
-                       $this->skin->theme_info = $this->theme_info($theme);
-
-                       // Get the URL to the zip file
-                       $r = $current->response[ $theme ];
-
-                       $options = array(
-                                                       'package' => $r['package'],
-                                                       'destination' => WP_CONTENT_DIR . '/themes',
-                                                       'clear_destination' => true,
-                                                       'clear_working' => true,
-                                                       'hook_extra' => array(
-                                                                                               'theme' => $theme
-                                                                                               )
-                                                       );
-
-                       $result = $this->run($options);
-
-                       $results[$theme] = $this->result;
-
-                       // Prevent credentials auth screen from displaying multiple times
-                       if ( false === $result )
-                               break;
-               } //end foreach $plugins
-
-               $this->maintenance_mode(false);
-
-               $this->skin->bulk_footer();
-
-               $this->skin->footer();
-
-               // Cleanup our hooks, in case something else does a upgrade on this connection.
-               remove_filter('upgrader_pre_install', array(&$this, 'current_before'), 10, 2);
-               remove_filter('upgrader_post_install', array(&$this, 'current_after'), 10, 2);
-               remove_filter('upgrader_clear_destination', array(&$this, 'delete_old_theme'), 10, 4);
-
-               // Force refresh of theme update information
-               delete_site_transient('update_themes');
-               search_theme_directories( true );
-               foreach ( wp_get_themes() as $theme )
-                       $theme->cache_delete();
-
-               return $results;
+       /**
+        * Releases an upgrader lock.
+        *
+        * @since 4.5.0
+        * @access public
+        * @static
+        *
+        * @see WP_Upgrader::create_lock()
+        *
+        * @param string $lock_name The name of this unique lock.
+        * @return bool True if the lock was successfully released. False on failure.
+        */
+       public static function release_lock( $lock_name ) {
+               return delete_option( $lock_name . '.lock' );
        }
 
-       function check_package($source) {
-               global $wp_filesystem;
-
-               if ( is_wp_error($source) )
-                       return $source;
+}
 
-               // Check the folder contains a valid theme
-               $working_directory = str_replace( $wp_filesystem->wp_content_dir(), trailingslashit(WP_CONTENT_DIR), $source);
-               if ( ! is_dir($working_directory) ) // Sanity check, if the above fails, lets not prevent installation.
-                       return $source;
+/** Plugin_Upgrader class */
+require_once ABSPATH . 'wp-admin/includes/class-plugin-upgrader.php';
 
-               // A proper archive should have a style.css file in the single subdirectory
-               if ( ! file_exists( $working_directory . 'style.css' ) )
-                       return new WP_Error( 'incompatible_archive', $this->strings['incompatible_archive'], __('The theme is missing the <code>style.css</code> stylesheet.') );
+/** Theme_Upgrader class */
+require_once ABSPATH . 'wp-admin/includes/class-theme-upgrader.php';
 
-               $info = get_file_data( $working_directory . 'style.css', array( 'Name' => 'Theme Name', 'Template' => 'Template' ) );
+/** Language_Pack_Upgrader class */
+require_once ABSPATH . 'wp-admin/includes/class-language-pack-upgrader.php';
 
-               if ( empty( $info['Name'] ) )
-                       return new WP_Error( 'incompatible_archive', $this->strings['incompatible_archive'], __("The <code>style.css</code> stylesheet doesn't contain a valid theme header.") );
+/** Core_Upgrader class */
+require_once ABSPATH . 'wp-admin/includes/class-core-upgrader.php';
 
-               // If it's not a child theme, it must have at least an index.php to be legit.
-               if ( empty( $info['Template'] ) && ! file_exists( $working_directory . 'index.php' ) )
-                       return new WP_Error( 'incompatible_archive', $this->strings['incompatible_archive'], __('The theme is missing the <code>index.php</code> file.') );
+/** File_Upload_Upgrader class */
+require_once ABSPATH . 'wp-admin/includes/class-file-upload-upgrader.php';
 
-               return $source;
-       }
-
-       function current_before($return, $theme) {
-
-               if ( is_wp_error($return) )
-                       return $return;
-
-               $theme = isset($theme['theme']) ? $theme['theme'] : '';
-
-               if ( $theme != get_stylesheet() ) //If not current
-                       return $return;
-               //Change to maintenance mode now.
-               if ( ! $this->bulk )
-                       $this->maintenance_mode(true);
-
-               return $return;
-       }
-
-       function current_after($return, $theme) {
-               if ( is_wp_error($return) )
-                       return $return;
-
-               $theme = isset($theme['theme']) ? $theme['theme'] : '';
-
-               if ( $theme != get_stylesheet() ) // If not current
-                       return $return;
-
-               // Ensure stylesheet name hasnt changed after the upgrade:
-               // @TODO: Note, This doesn't handle the Template changing, or the Template name changing.
-               if ( $theme == get_stylesheet() && $theme != $this->result['destination_name'] ) {
-                       $theme_info = $this->theme_info();
-                       $stylesheet = $this->result['destination_name'];
-                       $template = $theme_info->get_template();
-                       switch_theme($template, $stylesheet, true);
-               }
-
-               //Time to remove maintenance mode
-               if ( ! $this->bulk )
-                       $this->maintenance_mode(false);
-               return $return;
-       }
-
-       function delete_old_theme($removed, $local_destination, $remote_destination, $theme) {
-               global $wp_filesystem;
-
-               $theme = isset($theme['theme']) ? $theme['theme'] : '';
-
-               if ( is_wp_error($removed) || empty($theme) )
-                       return $removed; //Pass errors through.
-
-               $themes_dir = $wp_filesystem->wp_themes_dir();
-               if ( $wp_filesystem->exists( trailingslashit($themes_dir) . $theme ) )
-                       if ( ! $wp_filesystem->delete( trailingslashit($themes_dir) . $theme, true ) )
-                               return false;
-               return true;
-       }
-
-       function theme_info($theme = null) {
-
-               if ( empty($theme) ) {
-                       if ( !empty($this->result['destination_name']) )
-                               $theme = $this->result['destination_name'];
-                       else
-                               return false;
-               }
-               return wp_get_theme( $theme, WP_CONTENT_DIR . '/themes/' );
-       }
-
-}
-
-/**
- * Core Upgrader class for WordPress. It allows for WordPress to upgrade itself in combination with the wp-admin/includes/update-core.php file
- *
- * @TODO More Detailed docs, for methods as well.
- *
- * @package WordPress
- * @subpackage Upgrader
- * @since 2.8.0
- */
-class Core_Upgrader extends WP_Upgrader {
-
-       function upgrade_strings() {
-               $this->strings['up_to_date'] = __('WordPress is at the latest version.');
-               $this->strings['no_package'] = __('Update package not available.');
-               $this->strings['downloading_package'] = __('Downloading update from <span class="code">%s</span>&#8230;');
-               $this->strings['unpack_package'] = __('Unpacking the update&#8230;');
-               $this->strings['copy_failed'] = __('Could not copy files.');
-               $this->strings['copy_failed_space'] = __('Could not copy files. You may have run out of disk space.' );
-       }
-
-       function upgrade($current) {
-               global $wp_filesystem, $wp_version;
-
-               $this->init();
-               $this->upgrade_strings();
-
-               if ( !empty($feedback) )
-                       add_filter('update_feedback', $feedback);
-
-               // Is an update available?
-               if ( !isset( $current->response ) || $current->response == 'latest' )
-                       return new WP_Error('up_to_date', $this->strings['up_to_date']);
-
-               $res = $this->fs_connect( array(ABSPATH, WP_CONTENT_DIR) );
-               if ( is_wp_error($res) )
-                       return $res;
-
-               $wp_dir = trailingslashit($wp_filesystem->abspath());
-
-               // If partial update is returned from the API, use that, unless we're doing a reinstall.
-               // If we cross the new_bundled version number, then use the new_bundled zip.
-               // Don't though if the constant is set to skip bundled items.
-               // If the API returns a no_content zip, go with it. Finally, default to the full zip.
-               if ( $current->packages->partial && 'reinstall' != $current->response && $wp_version == $current->partial_version )
-                       $to_download = 'partial';
-               elseif ( $current->packages->new_bundled && version_compare( $wp_version, $current->new_bundled, '<' )
-                       && ( ! defined( 'CORE_UPGRADE_SKIP_NEW_BUNDLED' ) || ! CORE_UPGRADE_SKIP_NEW_BUNDLED ) )
-                       $to_download = 'new_bundled';
-               elseif ( $current->packages->no_content )
-                       $to_download = 'no_content';
-               else
-                       $to_download = 'full';
-
-               $download = $this->download_package( $current->packages->$to_download );
-               if ( is_wp_error($download) )
-                       return $download;
-
-               $working_dir = $this->unpack_package( $download );
-               if ( is_wp_error($working_dir) )
-                       return $working_dir;
-
-               // Copy update-core.php from the new version into place.
-               if ( !$wp_filesystem->copy($working_dir . '/wordpress/wp-admin/includes/update-core.php', $wp_dir . 'wp-admin/includes/update-core.php', true) ) {
-                       $wp_filesystem->delete($working_dir, true);
-                       return new WP_Error('copy_failed', $this->strings['copy_failed']);
-               }
-               $wp_filesystem->chmod($wp_dir . 'wp-admin/includes/update-core.php', FS_CHMOD_FILE);
-
-               require(ABSPATH . 'wp-admin/includes/update-core.php');
-
-               if ( ! function_exists( 'update_core' ) )
-                       return new WP_Error( 'copy_failed_space', $this->strings['copy_failed_space'] );
-
-               return update_core($working_dir, $wp_dir);
-       }
-
-}
-
-/**
- * Generic Skin for the WordPress Upgrader classes. This skin is designed to be extended for specific purposes.
- *
- * @TODO More Detailed docs, for methods as well.
- *
- * @package WordPress
- * @subpackage Upgrader
- * @since 2.8.0
- */
-class WP_Upgrader_Skin {
-
-       var $upgrader;
-       var $done_header = false;
-       var $result = false;
-
-       function __construct($args = array()) {
-               $defaults = array( 'url' => '', 'nonce' => '', 'title' => '', 'context' => false );
-               $this->options = wp_parse_args($args, $defaults);
-       }
-
-       function set_upgrader(&$upgrader) {
-               if ( is_object($upgrader) )
-                       $this->upgrader =& $upgrader;
-               $this->add_strings();
-       }
-
-       function add_strings() {
-       }
-
-       function set_result($result) {
-               $this->result = $result;
-       }
-
-       function request_filesystem_credentials($error = false) {
-               $url = $this->options['url'];
-               $context = $this->options['context'];
-               if ( !empty($this->options['nonce']) )
-                       $url = wp_nonce_url($url, $this->options['nonce']);
-               return request_filesystem_credentials($url, '', $error, $context); //Possible to bring inline, Leaving as is for now.
-       }
-
-       function header() {
-               if ( $this->done_header )
-                       return;
-               $this->done_header = true;
-               echo '<div class="wrap">';
-               echo screen_icon();
-               echo '<h2>' . $this->options['title'] . '</h2>';
-       }
-       function footer() {
-               echo '</div>';
-       }
-
-       function error($errors) {
-               if ( ! $this->done_header )
-                       $this->header();
-               if ( is_string($errors) ) {
-                       $this->feedback($errors);
-               } elseif ( is_wp_error($errors) && $errors->get_error_code() ) {
-                       foreach ( $errors->get_error_messages() as $message ) {
-                               if ( $errors->get_error_data() )
-                                       $this->feedback($message . ' ' . $errors->get_error_data() );
-                               else
-                                       $this->feedback($message);
-                       }
-               }
-       }
-
-       function feedback($string) {
-               if ( isset( $this->upgrader->strings[$string] ) )
-                       $string = $this->upgrader->strings[$string];
-
-               if ( strpos($string, '%') !== false ) {
-                       $args = func_get_args();
-                       $args = array_splice($args, 1);
-                       if ( !empty($args) )
-                               $string = vsprintf($string, $args);
-               }
-               if ( empty($string) )
-                       return;
-               show_message($string);
-       }
-       function before() {}
-       function after() {}
-
-}
-
-/**
- * Plugin Upgrader Skin for WordPress Plugin Upgrades.
- *
- * @TODO More Detailed docs, for methods as well.
- *
- * @package WordPress
- * @subpackage Upgrader
- * @since 2.8.0
- */
-class Plugin_Upgrader_Skin extends WP_Upgrader_Skin {
-       var $plugin = '';
-       var $plugin_active = false;
-       var $plugin_network_active = false;
-
-       function __construct($args = array()) {
-               $defaults = array( 'url' => '', 'plugin' => '', 'nonce' => '', 'title' => __('Update Plugin') );
-               $args = wp_parse_args($args, $defaults);
-
-               $this->plugin = $args['plugin'];
-
-               $this->plugin_active = is_plugin_active( $this->plugin );
-               $this->plugin_network_active = is_plugin_active_for_network( $this->plugin );
-
-               parent::__construct($args);
-       }
-
-       function after() {
-               $this->plugin = $this->upgrader->plugin_info();
-               if ( !empty($this->plugin) && !is_wp_error($this->result) && $this->plugin_active ){
-                       echo '<iframe style="border:0;overflow:hidden" width="100%" height="170px" src="' . wp_nonce_url('update.php?action=activate-plugin&networkwide=' . $this->plugin_network_active . '&plugin=' . $this->plugin, 'activate-plugin_' . $this->plugin) .'"></iframe>';
-               }
-
-               $update_actions =  array(
-                       'activate_plugin' => '<a href="' . wp_nonce_url('plugins.php?action=activate&amp;plugin=' . $this->plugin, 'activate-plugin_' . $this->plugin) . '" title="' . esc_attr__('Activate this plugin') . '" target="_parent">' . __('Activate Plugin') . '</a>',
-                       'plugins_page' => '<a href="' . self_admin_url('plugins.php') . '" title="' . esc_attr__('Go to plugins page') . '" target="_parent">' . __('Return to Plugins page') . '</a>'
-               );
-               if ( $this->plugin_active )
-                       unset( $update_actions['activate_plugin'] );
-               if ( ! $this->result || is_wp_error($this->result) )
-                       unset( $update_actions['activate_plugin'] );
-
-               $update_actions = apply_filters('update_plugin_complete_actions', $update_actions, $this->plugin);
-               if ( ! empty($update_actions) )
-                       $this->feedback(implode(' | ', (array)$update_actions));
-       }
-
-       function before() {
-               if ( $this->upgrader->show_before ) {
-                       echo $this->upgrader->show_before;
-                       $this->upgrader->show_before = '';
-               }
-       }
-}
-
-/**
- * Plugin Upgrader Skin for WordPress Plugin Upgrades.
- *
- * @package WordPress
- * @subpackage Upgrader
- * @since 3.0.0
- */
-class Bulk_Upgrader_Skin extends WP_Upgrader_Skin {
-       var $in_loop = false;
-       var $error = false;
-
-       function __construct($args = array()) {
-               $defaults = array( 'url' => '', 'nonce' => '' );
-               $args = wp_parse_args($args, $defaults);
-
-               parent::__construct($args);
-       }
-
-       function add_strings() {
-               $this->upgrader->strings['skin_upgrade_start'] = __('The update process is starting. This process may take a while on some hosts, so please be patient.');
-               $this->upgrader->strings['skin_update_failed_error'] = __('An error occurred while updating %1$s: <strong>%2$s</strong>.');
-               $this->upgrader->strings['skin_update_failed'] = __('The update of %1$s failed.');
-               $this->upgrader->strings['skin_update_successful'] = __('%1$s updated successfully.').' <a onclick="%2$s" href="#" class="hide-if-no-js"><span>'.__('Show Details').'</span><span class="hidden">'.__('Hide Details').'</span>.</a>';
-               $this->upgrader->strings['skin_upgrade_end'] = __('All updates have been completed.');
-       }
-
-       function feedback($string) {
-               if ( isset( $this->upgrader->strings[$string] ) )
-                       $string = $this->upgrader->strings[$string];
-
-               if ( strpos($string, '%') !== false ) {
-                       $args = func_get_args();
-                       $args = array_splice($args, 1);
-                       if ( !empty($args) )
-                               $string = vsprintf($string, $args);
-               }
-               if ( empty($string) )
-                       return;
-               if ( $this->in_loop )
-                       echo "$string<br />\n";
-               else
-                       echo "<p>$string</p>\n";
-       }
-
-       function header() {
-               // Nothing, This will be displayed within a iframe.
-       }
-
-       function footer() {
-               // Nothing, This will be displayed within a iframe.
-       }
-       function error($error) {
-               if ( is_string($error) && isset( $this->upgrader->strings[$error] ) )
-                       $this->error = $this->upgrader->strings[$error];
-
-               if ( is_wp_error($error) ) {
-                       foreach ( $error->get_error_messages() as $emessage ) {
-                               if ( $error->get_error_data() )
-                                       $messages[] = $emessage . ' ' . $error->get_error_data();
-                               else
-                                       $messages[] = $emessage;
-                       }
-                       $this->error = implode(', ', $messages);
-               }
-               echo '<script type="text/javascript">jQuery(\'.waiting-' . esc_js($this->upgrader->update_current) . '\').hide();</script>';
-       }
-
-       function bulk_header() {
-               $this->feedback('skin_upgrade_start');
-       }
-
-       function bulk_footer() {
-               $this->feedback('skin_upgrade_end');
-       }
-
-       function before($title = '') {
-               $this->in_loop = true;
-               printf( '<h4>' . $this->upgrader->strings['skin_before_update_header'] . ' <img alt="" src="' . admin_url( 'images/wpspin_light.gif' ) . '" class="hidden waiting-' . $this->upgrader->update_current . '" style="vertical-align:middle;" /></h4>',  $title, $this->upgrader->update_current, $this->upgrader->update_count);
-               echo '<script type="text/javascript">jQuery(\'.waiting-' . esc_js($this->upgrader->update_current) . '\').show();</script>';
-               echo '<div class="update-messages hide-if-js" id="progress-' . esc_attr($this->upgrader->update_current) . '"><p>';
-               $this->flush_output();
-       }
-
-       function after($title = '') {
-               echo '</p></div>';
-               if ( $this->error || ! $this->result ) {
-                       if ( $this->error )
-                               echo '<div class="error"><p>' . sprintf($this->upgrader->strings['skin_update_failed_error'], $title, $this->error) . '</p></div>';
-                       else
-                               echo '<div class="error"><p>' . sprintf($this->upgrader->strings['skin_update_failed'], $title) . '</p></div>';
-
-                       echo '<script type="text/javascript">jQuery(\'#progress-' . esc_js($this->upgrader->update_current) . '\').show();</script>';
-               }
-               if ( !empty($this->result) && !is_wp_error($this->result) ) {
-                       echo '<div class="updated"><p>' . sprintf($this->upgrader->strings['skin_update_successful'], $title, 'jQuery(\'#progress-' . esc_js($this->upgrader->update_current) . '\').toggle();jQuery(\'span\', this).toggle(); return false;') . '</p></div>';
-                       echo '<script type="text/javascript">jQuery(\'.waiting-' . esc_js($this->upgrader->update_current) . '\').hide();</script>';
-               }
-
-               $this->reset();
-               $this->flush_output();
-       }
-
-       function reset() {
-               $this->in_loop = false;
-               $this->error = false;
-       }
-
-       function flush_output() {
-               wp_ob_end_flush_all();
-               flush();
-       }
-}
-
-class Bulk_Plugin_Upgrader_Skin extends Bulk_Upgrader_Skin {
-       var $plugin_info = array(); // Plugin_Upgrader::bulk() will fill this in.
-
-       function __construct($args = array()) {
-               parent::__construct($args);
-       }
-
-       function add_strings() {
-               parent::add_strings();
-               $this->upgrader->strings['skin_before_update_header'] = __('Updating Plugin %1$s (%2$d/%3$d)');
-       }
-
-       function before() {
-               parent::before($this->plugin_info['Title']);
-       }
-
-       function after() {
-               parent::after($this->plugin_info['Title']);
-       }
-       function bulk_footer() {
-               parent::bulk_footer();
-               $update_actions =  array(
-                       'plugins_page' => '<a href="' . self_admin_url('plugins.php') . '" title="' . esc_attr__('Go to plugins page') . '" target="_parent">' . __('Return to Plugins page') . '</a>',
-                       'updates_page' => '<a href="' . self_admin_url('update-core.php') . '" title="' . esc_attr__('Go to WordPress Updates page') . '" target="_parent">' . __('Return to WordPress Updates') . '</a>'
-               );
-
-               $update_actions = apply_filters('update_bulk_plugins_complete_actions', $update_actions, $this->plugin_info);
-               if ( ! empty($update_actions) )
-                       $this->feedback(implode(' | ', (array)$update_actions));
-       }
-}
-
-class Bulk_Theme_Upgrader_Skin extends Bulk_Upgrader_Skin {
-       var $theme_info = array(); // Theme_Upgrader::bulk() will fill this in.
-
-       function __construct($args = array()) {
-               parent::__construct($args);
-       }
-
-       function add_strings() {
-               parent::add_strings();
-               $this->upgrader->strings['skin_before_update_header'] = __('Updating Theme %1$s (%2$d/%3$d)');
-       }
-
-       function before() {
-               parent::before( $this->theme_info->display('Name') );
-       }
-
-       function after() {
-               parent::after( $this->theme_info->display('Name') );
-       }
-
-       function bulk_footer() {
-               parent::bulk_footer();
-               $update_actions =  array(
-                       'themes_page' => '<a href="' . self_admin_url('themes.php') . '" title="' . esc_attr__('Go to themes page') . '" target="_parent">' . __('Return to Themes page') . '</a>',
-                       'updates_page' => '<a href="' . self_admin_url('update-core.php') . '" title="' . esc_attr__('Go to WordPress Updates page') . '" target="_parent">' . __('Return to WordPress Updates') . '</a>'
-               );
-
-               $update_actions = apply_filters('update_bulk_theme_complete_actions', $update_actions, $this->theme_info );
-               if ( ! empty($update_actions) )
-                       $this->feedback(implode(' | ', (array)$update_actions));
-       }
-}
-
-/**
- * Plugin Installer Skin for WordPress Plugin Installer.
- *
- * @TODO More Detailed docs, for methods as well.
- *
- * @package WordPress
- * @subpackage Upgrader
- * @since 2.8.0
- */
-class Plugin_Installer_Skin extends WP_Upgrader_Skin {
-       var $api;
-       var $type;
-
-       function __construct($args = array()) {
-               $defaults = array( 'type' => 'web', 'url' => '', 'plugin' => '', 'nonce' => '', 'title' => '' );
-               $args = wp_parse_args($args, $defaults);
-
-               $this->type = $args['type'];
-               $this->api = isset($args['api']) ? $args['api'] : array();
-
-               parent::__construct($args);
-       }
-
-       function before() {
-               if ( !empty($this->api) )
-                       $this->upgrader->strings['process_success'] = sprintf( __('Successfully installed the plugin <strong>%s %s</strong>.'), $this->api->name, $this->api->version);
-       }
-
-       function after() {
-
-               $plugin_file = $this->upgrader->plugin_info();
-
-               $install_actions = array();
-
-               $from = isset($_GET['from']) ? stripslashes($_GET['from']) : 'plugins';
-
-               if ( 'import' == $from )
-                       $install_actions['activate_plugin'] = '<a href="' . wp_nonce_url('plugins.php?action=activate&amp;from=import&amp;plugin=' . $plugin_file, 'activate-plugin_' . $plugin_file) . '" title="' . esc_attr__('Activate this plugin') . '" target="_parent">' . __('Activate Plugin &amp; Run Importer') . '</a>';
-               else
-                       $install_actions['activate_plugin'] = '<a href="' . wp_nonce_url('plugins.php?action=activate&amp;plugin=' . $plugin_file, 'activate-plugin_' . $plugin_file) . '" title="' . esc_attr__('Activate this plugin') . '" target="_parent">' . __('Activate Plugin') . '</a>';
-
-               if ( is_multisite() && current_user_can( 'manage_network_plugins' ) ) {
-                       $install_actions['network_activate'] = '<a href="' . wp_nonce_url('plugins.php?action=activate&amp;networkwide=1&amp;plugin=' . $plugin_file, 'activate-plugin_' . $plugin_file) . '" title="' . esc_attr__('Activate this plugin for all sites in this network') . '" target="_parent">' . __('Network Activate') . '</a>';
-                       unset( $install_actions['activate_plugin'] );
-               }
-
-               if ( 'import' == $from )
-                       $install_actions['importers_page'] = '<a href="' . admin_url('import.php') . '" title="' . esc_attr__('Return to Importers') . '" target="_parent">' . __('Return to Importers') . '</a>';
-               else if ( $this->type == 'web' )
-                       $install_actions['plugins_page'] = '<a href="' . self_admin_url('plugin-install.php') . '" title="' . esc_attr__('Return to Plugin Installer') . '" target="_parent">' . __('Return to Plugin Installer') . '</a>';
-               else
-                       $install_actions['plugins_page'] = '<a href="' . self_admin_url('plugins.php') . '" title="' . esc_attr__('Return to Plugins page') . '" target="_parent">' . __('Return to Plugins page') . '</a>';
-
-               if ( ! $this->result || is_wp_error($this->result) ) {
-                       unset( $install_actions['activate_plugin'] );
-                       unset( $install_actions['network_activate'] );
-               }
-               $install_actions = apply_filters('install_plugin_complete_actions', $install_actions, $this->api, $plugin_file);
-               if ( ! empty($install_actions) )
-                       $this->feedback(implode(' | ', (array)$install_actions));
-       }
-}
-
-/**
- * Theme Installer Skin for the WordPress Theme Installer.
- *
- * @TODO More Detailed docs, for methods as well.
- *
- * @package WordPress
- * @subpackage Upgrader
- * @since 2.8.0
- */
-class Theme_Installer_Skin extends WP_Upgrader_Skin {
-       var $api;
-       var $type;
-
-       function __construct($args = array()) {
-               $defaults = array( 'type' => 'web', 'url' => '', 'theme' => '', 'nonce' => '', 'title' => '' );
-               $args = wp_parse_args($args, $defaults);
-
-               $this->type = $args['type'];
-               $this->api = isset($args['api']) ? $args['api'] : array();
-
-               parent::__construct($args);
-       }
-
-       function before() {
-               if ( !empty($this->api) )
-                       $this->upgrader->strings['process_success'] = sprintf( $this->upgrader->strings['process_success_specific'], $this->api->name, $this->api->version);
-       }
-
-       function after() {
-               if ( empty($this->upgrader->result['destination_name']) )
-                       return;
-
-               $theme_info = $this->upgrader->theme_info();
-               if ( empty( $theme_info ) )
-                       return;
-
-               $name       = $theme_info->display('Name');
-               $stylesheet = $this->upgrader->result['destination_name'];
-               $template   = $theme_info->get_template();
-
-               $preview_link = add_query_arg( array(
-                       'preview'    => 1,
-                       'template'   => $template,
-                       'stylesheet' => $stylesheet,
-               ), trailingslashit( get_home_url() ) );
-
-               $activate_link = add_query_arg( array(
-                       'action'     => 'activate',
-                       'template'   => $template,
-                       'stylesheet' => $stylesheet,
-               ), admin_url('themes.php') );
-               $activate_link = wp_nonce_url( $activate_link, 'switch-theme_' . $stylesheet );
-
-               $install_actions = array();
-               $install_actions['preview']  = '<a href="' . esc_url( $preview_link ) . '" class="hide-if-customize" title="' . esc_attr( sprintf( __('Preview &#8220;%s&#8221;'), $name ) ) . '">' . __('Preview') . '</a>';
-               $install_actions['preview'] .= '<a href="' . wp_customize_url( $stylesheet ) . '" class="hide-if-no-customize load-customize" title="' . esc_attr( sprintf( __('Preview &#8220;%s&#8221;'), $name ) ) . '">' . __('Live Preview') . '</a>';
-               $install_actions['activate'] = '<a href="' . esc_url( $activate_link ) . '" class="activatelink" title="' . esc_attr( sprintf( __('Activate &#8220;%s&#8221;'), $name ) ) . '">' . __('Activate') . '</a>';
-
-               if ( is_network_admin() && current_user_can( 'manage_network_themes' ) )
-                       $install_actions['network_enable'] = '<a href="' . esc_url( wp_nonce_url( 'themes.php?action=enable&amp;theme=' . $stylesheet, 'enable-theme_' . $stylesheet ) ) . '" title="' . esc_attr__( 'Enable this theme for all sites in this network' ) . '" target="_parent">' . __( 'Network Enable' ) . '</a>';
-
-               if ( $this->type == 'web' )
-                       $install_actions['themes_page'] = '<a href="' . self_admin_url('theme-install.php') . '" title="' . esc_attr__('Return to Theme Installer') . '" target="_parent">' . __('Return to Theme Installer') . '</a>';
-               else
-                       $install_actions['themes_page'] = '<a href="' . self_admin_url('themes.php') . '" title="' . esc_attr__('Themes page') . '" target="_parent">' . __('Return to Themes page') . '</a>';
-
-               if ( ! $this->result || is_wp_error($this->result) || is_network_admin() )
-                       unset( $install_actions['activate'], $install_actions['preview'] );
-
-               $install_actions = apply_filters('install_theme_complete_actions', $install_actions, $this->api, $stylesheet, $theme_info);
-               if ( ! empty($install_actions) )
-                       $this->feedback(implode(' | ', (array)$install_actions));
-       }
-}
-
-/**
- * Theme Upgrader Skin for WordPress Theme Upgrades.
- *
- * @TODO More Detailed docs, for methods as well.
- *
- * @package WordPress
- * @subpackage Upgrader
- * @since 2.8.0
- */
-class Theme_Upgrader_Skin extends WP_Upgrader_Skin {
-       var $theme = '';
-
-       function __construct($args = array()) {
-               $defaults = array( 'url' => '', 'theme' => '', 'nonce' => '', 'title' => __('Update Theme') );
-               $args = wp_parse_args($args, $defaults);
-
-               $this->theme = $args['theme'];
-
-               parent::__construct($args);
-       }
-
-       function after() {
-
-               $update_actions = array();
-               if ( ! empty( $this->upgrader->result['destination_name'] ) && $theme_info = $this->upgrader->theme_info() ) {
-                       $name       = $theme_info->display('Name');
-                       $stylesheet = $this->upgrader->result['destination_name'];
-                       $template   = $theme_info->get_template();
-
-                       $preview_link = add_query_arg( array(
-                               'preview'    => 1,
-                               'template'   => $template,
-                               'stylesheet' => $stylesheet,
-                       ), trailingslashit( get_home_url() ) );
-
-                       $activate_link = add_query_arg( array(
-                               'action'     => 'activate',
-                               'template'   => $template,
-                               'stylesheet' => $stylesheet,
-                       ), admin_url('themes.php') );
-                       $activate_link = wp_nonce_url( $activate_link, 'switch-theme_' . $stylesheet );
-
-                       if ( get_stylesheet() == $stylesheet ) {
-                               $update_actions['preview']  = '<a href="' . wp_customize_url( $stylesheet ) . '" class="hide-if-no-customize load-customize" title="' . esc_attr( sprintf( __('Customize &#8220;%s&#8221;'), $name ) ) . '">' . __('Customize') . '</a>';
-                       } else {
-                               $update_actions['preview']  = '<a href="' . esc_url( $preview_link ) . '" class="hide-if-customize" title="' . esc_attr( sprintf( __('Preview &#8220;%s&#8221;'), $name ) ) . '">' . __('Preview') . '</a>';
-                               $update_actions['preview'] .= '<a href="' . wp_customize_url( $stylesheet ) . '" class="hide-if-no-customize load-customize" title="' . esc_attr( sprintf( __('Preview &#8220;%s&#8221;'), $name ) ) . '">' . __('Live Preview') . '</a>';
-                               $update_actions['activate'] = '<a href="' . esc_url( $activate_link ) . '" class="activatelink" title="' . esc_attr( sprintf( __('Activate &#8220;%s&#8221;'), $name ) ) . '">' . __('Activate') . '</a>';
-                       }
-
-                       if ( ! $this->result || is_wp_error( $this->result ) || is_network_admin() )
-                               unset( $update_actions['preview'], $update_actions['activate'] );
-               }
-
-               $update_actions['themes_page'] = '<a href="' . self_admin_url('themes.php') . '" title="' . esc_attr__('Return to Themes page') . '" target="_parent">' . __('Return to Themes page') . '</a>';
-
-               $update_actions = apply_filters('update_theme_complete_actions', $update_actions, $this->theme);
-               if ( ! empty($update_actions) )
-                       $this->feedback(implode(' | ', (array)$update_actions));
-       }
-}
-
-/**
- * Upgrade Skin helper for File uploads. This class handles the upload process and passes it as if its a local file to the Upgrade/Installer functions.
- *
- * @TODO More Detailed docs, for methods as well.
- *
- * @package WordPress
- * @subpackage Upgrader
- * @since 2.8.0
- */
-class File_Upload_Upgrader {
-       var $package;
-       var $filename;
-       var $id = 0;
-
-       function __construct($form, $urlholder) {
-
-               if ( empty($_FILES[$form]['name']) && empty($_GET[$urlholder]) )
-                       wp_die(__('Please select a file'));
-
-               //Handle a newly uploaded file, Else assume its already been uploaded
-               if ( ! empty($_FILES) ) {
-                       $overrides = array( 'test_form' => false, 'test_type' => false );
-                       $file = wp_handle_upload( $_FILES[$form], $overrides );
-
-                       if ( isset( $file['error'] ) )
-                               wp_die( $file['error'] );
-
-                       $this->filename = $_FILES[$form]['name'];
-                       $this->package = $file['file'];
-
-                       // Construct the object array
-                       $object = array(
-                               'post_title' => $this->filename,
-                               'post_content' => $file['url'],
-                               'post_mime_type' => $file['type'],
-                               'guid' => $file['url'],
-                               'context' => 'upgrader',
-                               'post_status' => 'private'
-                       );
-
-                       // Save the data
-                       $this->id = wp_insert_attachment( $object, $file['file'] );
-
-                       // schedule a cleanup for 2 hours from now in case of failed install
-                       wp_schedule_single_event( time() + 7200, 'upgrader_scheduled_cleanup', array( $this->id ) );
-
-               } elseif ( is_numeric( $_GET[$urlholder] ) ) {
-                       // Numeric Package = previously uploaded file, see above.
-                       $this->id = (int) $_GET[$urlholder];
-                       $attachment = get_post( $this->id );
-                       if ( empty($attachment) )
-                               wp_die(__('Please select a file'));
-
-                       $this->filename = $attachment->post_title;
-                       $this->package = get_attached_file( $attachment->ID );
-               } else {
-                       // Else, It's set to something, Back compat for plugins using the old (pre-3.3) File_Uploader handler.
-                       if ( ! ( ( $uploads = wp_upload_dir() ) && false === $uploads['error'] ) )
-                               wp_die( $uploads['error'] );
-
-                       $this->filename = $_GET[$urlholder];
-                       $this->package = $uploads['basedir'] . '/' . $this->filename;
-               }
-       }
-
-       function cleanup() {
-               if ( $this->id )
-                       wp_delete_attachment( $this->id );
-
-               elseif ( file_exists( $this->package ) )
-                       return @unlink( $this->package );
-
-               return true;
-       }
-}
\ No newline at end of file
+/** WP_Automatic_Updater class */
+require_once ABSPATH . 'wp-admin/includes/class-wp-automatic-updater.php';