From 9a60eab15251e1a429cb2741f562fa0841cdd137 Mon Sep 17 00:00:00 2001
From: Philipp Holzer <admin@philipp.info>
Date: Sun, 10 Mar 2019 19:59:20 +0100
Subject: [PATCH] Skip update if already done

---
 src/Core/Update.php | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/Core/Update.php b/src/Core/Update.php
index e0a7c4a26..aa400d1e8 100644
--- a/src/Core/Update.php
+++ b/src/Core/Update.php
@@ -68,7 +68,7 @@ class Update
 			Lock::release('dbupdate', true);
 		}
 
-		$build = Config::get('system', 'build');
+		$build = Config::get('system', 'build', null, true);
 
 		if (empty($build) || ($build > DB_UPDATE_VERSION)) {
 			$build = DB_UPDATE_VERSION - 1;
@@ -89,6 +89,13 @@ class Update
 				// If the Lock is acquired, never release it automatically to avoid double updates
 				if (Lock::acquire('dbupdate', 120, Cache::INFINITE)) {
 
+					// Checks if the build changed during Lock acquiring (so no double update occurs)
+					$retryBuild = Config::get('system', 'build', null, true);
+					if ($retryBuild !== $build) {
+						Lock::release('dbupdate');
+						return '';
+					}
+
 					// run the pre_update_nnnn functions in update.php
 					for ($x = $stored + 1; $x <= $current; $x++) {
 						$r = self::runUpdateFunction($x, 'pre_update');