Avoid double update runs

diff --git a/src/Core/Update.php b/src/Core/Update.php
index e0a7c4a..b849b4c 100644 (file)
--- a/src/Core/Update.php
+++ b/src/Core/Update.php
@@ -68,68 +68,67 @@ class Update
                        Lock::release('dbupdate', true);
                }
 
-               $build = Config::get('system', 'build');
+               $current = intval(DB_UPDATE_VERSION);
+               $stored = self::getBuild();
 
-               if (empty($build) || ($build > DB_UPDATE_VERSION)) {
-                       $build = DB_UPDATE_VERSION - 1;
-                       Config::set('system', 'build', $build);
-               }
-
-               if ($build != DB_UPDATE_VERSION || $force) {
+               if ($stored < $current || $force) {
                        require_once 'update.php';
 
-                       $stored = intval($build);
-                       $current = intval(DB_UPDATE_VERSION);
-                       if ($stored < $current || $force) {
-                               Config::load('database');
+                       Config::load('database');
 
-                               Logger::log('Update from \'' . $stored . '\'  to \'' . $current . '\' - starting', Logger::DEBUG);
+                       Logger::log('Update from \'' . $stored . '\'  to \'' . $current . '\' - starting', Logger::DEBUG);
 
-                               // Compare the current structure with the defined structure
-                               // If the Lock is acquired, never release it automatically to avoid double updates
-                               if (Lock::acquire('dbupdate', 120, Cache::INFINITE)) {
+                       // Compare the current structure with the defined structure
+                       // If the Lock is acquired, never release it automatically to avoid double updates
+                       if (Lock::acquire('dbupdate', 0, Cache::INFINITE)) {
 
-                                       // run the pre_update_nnnn functions in update.php
-                                       for ($x = $stored + 1; $x <= $current; $x++) {
-                                               $r = self::runUpdateFunction($x, 'pre_update');
-                                               if (!$r) {
-                                                       break;
-                                               }
-                                       }
+                               // recheck again in case we accidentally spawned multiple updates
+                               $stored = intval(self::getBuild());
+                               if ($stored >= $current) {
+                                       Lock::release('dbupdate');
+                                       return '';
+                               }
 
-                                       // update the structure in one call
-                                       $retval = DBStructure::update($basePath, $verbose, true);
-                                       if (!empty($retval)) {
-                                               if ($sendMail) {
-                                                       self::updateFailed(
-                                                               DB_UPDATE_VERSION,
-                                                               $retval
-                                                       );
-                                               }
-                                               Logger::log('ERROR: Update from \'' . $stored . '\'  to \'' . $current . '\' - failed:  ' - $retval, Logger::ALL);
-                                               Lock::release('dbupdate');
-                                               return $retval;
-                                       } else {
-                                               Config::set('database', 'last_successful_update', $current);
-                                               Config::set('database', 'last_successful_update_time', time());
-                                               Logger::log('Update from \'' . $stored . '\'  to \'' . $current . '\' - finished', Logger::DEBUG);
+                               // run the pre_update_nnnn functions in update.php
+                               for ($x = $stored + 1; $x <= $current; $x++) {
+                                       $r = self::runUpdateFunction($x, 'pre_update');
+                                       if (!$r) {
+                                               break;
                                        }
+                               }
 
-                                       // run the update_nnnn functions in update.php
-                                       for ($x = $stored + 1; $x <= $current; $x++) {
-                                               $r = self::runUpdateFunction($x, 'update');
-                                               if (!$r) {
-                                                       break;
-                                               }
+                               // update the structure in one call
+                               $retval = DBStructure::update($basePath, $verbose, true);
+                               if (!empty($retval)) {
+                                       if ($sendMail) {
+                                               self::updateFailed(
+                                                       DB_UPDATE_VERSION,
+                                                       $retval
+                                               );
                                        }
+                                       Logger::log('ERROR: Update from \'' . $stored . '\'  to \'' . $current . '\' - failed:  ' - $retval, Logger::ALL);
+                                       Lock::release('dbupdate');
+                                       return $retval;
+                               } else {
+                                       Config::set('database', 'last_successful_update', $current);
+                                       Config::set('database', 'last_successful_update_time', time());
+                                       Logger::log('Update from \'' . $stored . '\'  to \'' . $current . '\' - finished', Logger::DEBUG);
+                               }
 
-                                       Logger::log('Update from \'' . $stored . '\'  to \'' . $current . '\' - successful', Logger::DEBUG);
-                                       if ($sendMail) {
-                                               self::updateSuccessfull($stored, $current);
+                               // run the update_nnnn functions in update.php
+                               for ($x = $stored + 1; $x <= $current; $x++) {
+                                       $r = self::runUpdateFunction($x, 'update');
+                                       if (!$r) {
+                                               break;
                                        }
+                               }
 
-                                       Lock::release('dbupdate');
+                               Logger::log('Update from \'' . $stored . '\'  to \'' . $current . '\' - successful', Logger::DEBUG);
+                               if ($sendMail) {
+                                       self::updateSuccessfull($stored, $current);
                                }
+
+                               Lock::release('dbupdate');
                        }
                }
 
@@ -293,4 +292,16 @@ class Update
                //try the logger
                Logger::log("Database structure update successful.", Logger::TRACE);
        }
+
+       private static function getBuild()
+       {
+               $build = Config::get('system', 'build');
+
+               if (empty($build) || ($build > DB_UPDATE_VERSION)) {
+                       $build = DB_UPDATE_VERSION - 1;
+                       Config::set('system', 'build', $build);
+               }
+
+               return (is_int($build) ? intval($build) : DB_UPDATE_VERSION - 1);
+       }
 }