From 1227fc51195f6e53273681aa3a3c739e1178d6fa Mon Sep 17 00:00:00 2001
From: Sergey Biryukov <sergeybiryukov@git.wordpress.org>
Date: Mon, 11 Oct 2021 15:07:52 +0000
Subject: [PATCH] Upgrade/Install: Restore or clean up the temporary plugin or
 theme backup on shutdown.

This allows these actions to run ''after'' the main process, without affecting the update. Actions running on `shutdown` are immune to PHP timeouts, so in case the failure was due to a PHP timeout, we'll still be able to properly restore the previous version.

Follow-up to [51815], [51898], [51899].

Props aristath, peterwilsoncc.
See #54166.

git-svn-id: https://develop.svn.wordpress.org/trunk@51902 602fd350-edb4-49c9-b593-d223f7449a82
---
 src/wp-admin/includes/class-wp-upgrader.php | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/src/wp-admin/includes/class-wp-upgrader.php b/src/wp-admin/includes/class-wp-upgrader.php
index 0fab410240..225a7d4c69 100644
--- a/src/wp-admin/includes/class-wp-upgrader.php
+++ b/src/wp-admin/includes/class-wp-upgrader.php
@@ -843,7 +843,18 @@ class WP_Upgrader {
 		$this->skin->set_result( $result );
 		if ( is_wp_error( $result ) ) {
 			if ( ! empty( $options['hook_extra']['temp_backup'] ) ) {
-				$this->restore_temp_backup( $options['hook_extra']['temp_backup'] );
+				/*
+				 * Restore the backup on shutdown.
+				 * Actions running on `shutdown` are immune to PHP timeouts,
+				 * so in case the failure was due to a PHP timeout,
+				 * we'll still be able to properly restore the previous version.
+				 */
+				add_action(
+					'shutdown',
+					function() use ( $options ) {
+						$this->restore_temp_backup( $options['hook_extra']['temp_backup'] );
+					}
+				);
 			}
 			$this->skin->error( $result );
 
@@ -859,7 +870,13 @@ class WP_Upgrader {
 
 		// Clean up the backup kept in the temp-backup directory.
 		if ( ! empty( $options['hook_extra']['temp_backup'] ) ) {
-			$this->delete_temp_backup( $options['hook_extra']['temp_backup'] );
+			// Delete the backup on `shutdown` to avoid a PHP timeout.
+			add_action(
+				'shutdown',
+				function() use ( $options ) {
+					$this->delete_temp_backup( $options['hook_extra']['temp_backup'] );
+				}
+			);
 		}
 
 		if ( ! $options['is_multi'] ) {