Ticket #44458: 44458-1.diff

src/wp-includes/load.php

@@ -687 +687 @@
                         $plugins[] = WP_PLUGIN_DIR . '/' . $plugin;
                 }
         }
+
+        /*
+         * Remove plugins from the list of active plugins when we're on an admin or
+         * login screen and the plugin appears in the `skip_on_admin` list.
+         */
+        if ( 'wp-login.php' === $GLOBALS['pagenow']
+             || ( is_admin() && ! wp_doing_ajax() ) ) {
+                $skip_on_admin  = (array) get_option( 'skip_on_admin', array() );
+
+                if ( ! array_key_exists( 'plugin', $skip_on_admin ) ) {
+                        return $plugins;
+                }
+
+                foreach ( $plugins as $index => $plugin ) {
+                        $parts = explode(
+                                '/',
+                                str_replace( WP_CONTENT_DIR . '/', '', $plugin )
+                        );
+
+                        if ( in_array( $parts[1], $skip_on_admin['plugin'], true ) ) {
+                                unset( $plugins[ $index ] );
+                                // Store list of skipped plugins for displaying an admin notice.
+                                $GLOBALS['_skipped_plugin'][] = $plugin;
+                        }
+                }
+        }
+
         return $plugins;
 }
 
@@ -1250 +1277 @@
         }
         echo "\n###### wp_scraping_result_end:$scrape_key ######\n";
 }
+
+/**
+ * Wrap the shutdown handler function so it can be made pluggable at a later
+ * stage.
+ *
+ * @since 5.0.0
+ *
+ * @return void
+ */
+function wp_shutdown_handler_wrapper() {
+        if ( defined( 'WP_EXECUTION_SUCCEEDED' ) && WP_EXECUTION_SUCCEEDED ) {
+                return;
+        }
+
+        // Load the pluggable shutdown handler in case we found one.
+        if ( function_exists( 'wp_handle_shutdown' ) ) {
+                $stop_propagation = (bool) wp_handle_shutdown();
+
+                if ( $stop_propagation ) {
+                        return;
+                }
+        }
+
+        $error = error_get_last();
+
+        // No error, just skip the error handling code.
+        if ( null === $error ) {
+                return;
+        }
+
+        // This is only diagnostic code for the POC.
+        echo sprintf(
+                '<p>WordPress was shut down because a PHP error of type <strong>%d</strong> occurred in the file <strong><code>%s</code></strong> at line <strong><code>%d</code></strong>:<br><strong>%s</strong>',
+                $error['type'],
+                $error['file'],
+                $error['line'],
+                $error['message']
+        );
+
+        // For now, we only trigger our safe mode on parse errors.
+        if ( E_PARSE === $error['type'] ) {
+                $path = str_replace( WP_CONTENT_DIR . '/', '', $error['file'] );
+
+                $parts     = explode( '/', $path );
+                $type      = rtrim( array_shift( $parts ), 's' );
+                $extension = array_shift( $parts );
+
+                // This is only diagnostic code for the POC.
+                echo sprintf(
+                        '<p>A <strong>parse-time</strong> error was detected. The likely culprit was the <code>%s</code> %s.',
+                        $extension,
+                        'mu-plugin' === $type ? 'must-use plugin' : $type
+                );
+
+                $skip_on_admin   = get_option( 'skip_on_admin', array() );
+
+                if ( ! array_key_exists( $type, $skip_on_admin ) ) {
+                        $skip_on_admin[ $type ] = array();
+                }
+
+                if ( ! in_array( $extension, $skip_on_admin[ $type ], true ) ) {
+                        $skip_on_admin[ $type ][] = $extension;
+                }
+
+                update_option( 'skip_on_admin', $skip_on_admin );
+        }
+}
+
+/**
+ * Register the WordPress premature shutdown handler.
+ *
+ * @since 5.0.0
+ *
+ * @return void
+ */
+function wp_register_premature_shutdown_handler() {
+        register_shutdown_function( 'wp_shutdown_handler_wrapper' );
+}

src/wp-settings.php

@@ -20 +20 @@
 require( ABSPATH . WPINC . '/default-constants.php' );
 require_once( ABSPATH . WPINC . '/plugin.php' );
 
+// Make sure we register the premature shutdown handler as soon as possible.
+wp_register_premature_shutdown_handler();
+
 /*
  * These can't be directly globalized in version.php. When updating,
  * we're including version.php from another installation and don't want
@@ -40 +43 @@
 // Set initial default constants including WP_MEMORY_LIMIT, WP_MAX_MEMORY_LIMIT, WP_DEBUG, SCRIPT_DEBUG, WP_CONTENT_DIR and WP_CACHE.
 wp_initial_constants();
 
+/*
+ * Allow an optional shutdown handler to be included through a pluggable file.
+ * This file should register a function `wp_handle_shutdown( $context )` that
+ * returns a boolean value. If the return value evaluates to false, the default
+ * shutdown handler will not be executed.
+ */
+if ( is_readable( WP_CONTENT_DIR . '/shutdown-handler.php' ) ) {
+        include WP_CONTENT_DIR . '/shutdown-handler.php';
+}
+
 // Check for the required PHP version and for the MySQL extension or a database drop-in.
 wp_check_php_mysql_versions();
 
@@ -482 +495 @@
  * @since 3.0.0
  */
 do_action( 'wp_loaded' );
+
+/*
+ * Store the fact that we could successfully execute the entire WordPress
+ * lifecycle. This is used to skip the premature shutdown handler, as it cannot
+ * be unregistered.
+ */
+if ( ! defined( 'WP_EXECUTION_SUCCEEDED' ) ) {
+        define( 'WP_EXECUTION_SUCCEEDED', true );
+}