includes/batch.queue.inc

+<?php
+
+/**
+ * @file
+ * Queue handlers used by the Batch API.
+ *
+ * These implementations:
+ * - Ensure FIFO ordering.
+ * - Allow an item to be repeatedly claimed until it is actually deleted (no
+ *   notion of lease time or 'expire' date), to allow multipass operations.
+ */
+
+/**
+ * Defines a batch queue.
+ *
+ * Stale items from failed batches are cleaned from the {queue} table on cron
+ * using the 'created' date.
+ */
+class BatchQueue extends SystemQueue {
+
+  /**
+   * Overrides SystemQueue::claimItem().
+   *
+   * Unlike SystemQueue::claimItem(), this method provides a default lease
+   * time of 0 (no expiration) instead of 30. This allows the item to be
+   * claimed repeatedly until it is deleted.
+   */
+  public function claimItem($lease_time = 0) {
+    $item = db_query_range('SELECT data, item_id FROM {queue} q WHERE name = :name ORDER BY item_id ASC', 0, 1, array(':name' => $this->name))->fetchObject();
+    if ($item) {
+      $item->data = unserialize($item->data);
+      return $item;
+    }
+    return FALSE;
+  }
+
+  /**
+   * Retrieves all remaining items in the queue.
+   *
+   * This is specific to Batch API and is not part of the DrupalQueueInterface.
+   */
+  public function getAllItems() {
+    $result = array();
+    $items = db_query('SELECT data FROM {queue} q WHERE name = :name ORDER BY item_id ASC', array(':name' => $this->name))->fetchAll();
+    foreach ($items as $item) {
+      $result[] = unserialize($item->data);
+    }
+    return $result;
+  }
+}
+
+/**
+ * Defines a batch queue for non-progressive batches.
+ */
+class BatchMemoryQueue extends MemoryQueue {
+
+  /**
+   * Overrides MemoryQueue::claimItem().
+   *
+   * Unlike MemoryQueue::claimItem(), this method provides a default lease
+   * time of 0 (no expiration) instead of 30. This allows the item to be
+   * claimed repeatedly until it is deleted.
+   */
+  public function claimItem($lease_time = 0) {
+    if (!empty($this->queue)) {
+      reset($this->queue);
+      return current($this->queue);
+    }
+    return FALSE;
+  }
+
+  /**
+   * Retrieves all remaining items in the queue.
+   *
+   * This is specific to Batch API and is not part of the DrupalQueueInterface.
+   */
+  public function getAllItems() {
+    $result = array();
+    foreach ($this->queue as $item) {
+      $result[] = $item->data;
+    }
+    return $result;
+  }
+}

includes/cache-install.inc

 <?php
-// $Id$
 
 /**
- * A stub cache implementation to be used during the installation
- * process when database access is not yet available. Because Drupal's
- * caching system never requires that cached data be present, these
- * stub functions can short-circuit the process and sidestep the
- * need for any persistent storage. Obviously, using this cache
- * implementation during normal operations would have a negative impact
- * on performance.
+ * @file
+ * Provides a stub cache implementation to be used during installation.
+ */
+
+/**
+ * Defines a stub cache implementation to be used during installation.
+ *
+ * The stub implementation is needed when database access is not yet available.
+ * Because Drupal's caching system never requires that cached data be present,
+ * these stub functions can short-circuit the process and sidestep the need for
+ * any persistent storage. Obviously, using this cache implementation during
+ * normal operations would have a negative impact on performance.
  */
 class DrupalFakeCache extends DrupalDatabaseCache implements DrupalCacheInterface {
+
+  /**
+   * Overrides DrupalDatabaseCache::get().
+   */
   function get($cid) {
     return FALSE;
   }
 
+  /**
+   * Overrides DrupalDatabaseCache::getMultiple().
+   */
   function getMultiple(&$cids) {
     return array();
   }
 
-  function set($cid, $data, $expire = CACHE_PERMANENT, array $headers = NULL) {
+  /**
+   * Overrides DrupalDatabaseCache::set().
+   */
+  function set($cid, $data, $expire = CACHE_PERMANENT) {
   }
 
+  /**
+   * Overrides DrupalDatabaseCache::clear().
+   */
   function clear($cid = NULL, $wildcard = FALSE) {
     // If there is a database cache, attempt to clear it whenever possible. The
     // reason for doing this is that the database cache can accumulate data
     // during installation due to any full bootstraps that may occur at the
-    // same time (for example, AJAX requests triggered by the installer). If we
+    // same time (for example, Ajax requests triggered by the installer). If we
     // didn't try to clear it whenever this function is called, the data in the
     // cache would become stale; for example, the installer sometimes calls
     // variable_set(), which updates the {variable} table and then clears the
@@ -36,8 +53,7 @@ function clear($cid = NULL, $wildcard = FALSE) {
     // subtle bugs, some of which would not be fixed unless the site
     // administrator cleared the cache manually.
     try {
-      if (function_exists('drupal_install_initialize_database')) {
-        drupal_install_initialize_database();
+      if (class_exists('Database')) {
         parent::clear($cid, $wildcard);
       }
     }
@@ -49,6 +65,9 @@ function clear($cid = NULL, $wildcard = FALSE) {
     }
   }
 
+  /**
+   * Overrides DrupalDatabaseCache::isEmpty().
+   */
   function isEmpty() {
     return TRUE;
   }