Initial commit

drupal7/web/includes/registry.inc

@@ -0,0 +1,217 @@
+<?php
+
+/**
+ * @file
+ * This file contains the code registry parser engine.
+ */
+
+/**
+ * @defgroup registry Code registry
+ * @{
+ * The code registry engine.
+ *
+ * Drupal maintains an internal registry of all interfaces or classes in the
+ * system, allowing it to lazy-load code files as needed (reducing the amount
+ * of code that must be parsed on each request).
+ */
+
+/**
+ * Does the work for registry_update().
+ */
+function _registry_update() {
+  // The registry serves as a central autoloader for all classes, including
+  // the database query builders. However, the registry rebuild process
+  // requires write ability to the database, which means having access to the
+  // query builders that require the registry in order to be loaded. That
+  // causes a fatal race condition. Therefore we manually include the
+  // appropriate query builders for the currently active database before the
+  // registry rebuild process runs.
+  $connection_info = Database::getConnectionInfo();
+  $driver = $connection_info['default']['driver'];
+  require_once DRUPAL_ROOT . '/includes/database/query.inc';
+  require_once DRUPAL_ROOT . '/includes/database/select.inc';
+  require_once DRUPAL_ROOT . '/includes/database/' . $driver . '/query.inc';
+
+  // During the first registry rebuild in a request, we check all the files.
+  // During subsequent rebuilds, we only add new files. It makes the rebuilding
+  // process faster during installation of modules.
+  static $check_existing_files = TRUE;
+
+  // Get current list of modules and their files.
+  $modules = db_query("SELECT * FROM {system} WHERE type = 'module'")->fetchAll();
+  // Get the list of files we are going to parse.
+  $files = array();
+  foreach ($modules as &$module) {
+    $module->info = unserialize($module->info);
+    $dir = dirname($module->filename);
+
+    // Store the module directory for use in hook_registry_files_alter().
+    $module->dir = $dir;
+
+    if ($module->status) {
+      // Add files for enabled modules to the registry.
+      foreach ($module->info['files'] as $file) {
+        $files["$dir/$file"] = array('module' => $module->name, 'weight' => $module->weight);
+      }
+    }
+  }
+  foreach (file_scan_directory('includes', '/\.inc$/') as $filename => $file) {
+    $files["$filename"] = array('module' => '', 'weight' => 0);
+  }
+
+  // Initialize an empty array for the unchanged files.
+  $unchanged_files = array();
+
+  $transaction = db_transaction();
+  try {
+    // Allow modules to manually modify the list of files before the registry
+    // parses them. The $modules array provides the .info file information, which
+    // includes the list of files registered to each module. Any files in the
+    // list can then be added to the list of files that the registry will parse,
+    // or modify attributes of a file.
+    drupal_alter('registry_files', $files, $modules);
+
+    foreach (registry_get_parsed_files() as $filename => $file) {
+      // Add the hash for those files we have already parsed.
+      if (isset($files[$filename])) {
+        if ($check_existing_files === TRUE) {
+          $files[$filename]['hash'] = $file['hash'];
+        }
+        else {
+          // Ignore that file for this request, it has been parsed previously
+          // and it is unlikely it has changed.
+          unset($files[$filename]);
+          $unchanged_files[$filename] = $file;
+        }
+      }
+      else {
+        // Flush the registry of resources in files that are no longer on disc
+        // or are in files that no installed modules require to be parsed.
+        db_delete('registry')
+          ->condition('filename', $filename)
+          ->execute();
+        db_delete('registry_file')
+          ->condition('filename', $filename)
+          ->execute();
+      }
+    }
+
+    $parsed_files = _registry_parse_files($files);
+
+    // Add unchanged files to the files.
+    $files += $unchanged_files;
+
+    $unchanged_resources = array();
+    $lookup_cache = array();
+    if ($cache = cache_get('lookup_cache', 'cache_bootstrap')) {
+      $lookup_cache = $cache->data;
+    }
+    foreach ($lookup_cache as $key => $file) {
+      // If the file for this cached resource is carried over unchanged from
+      // the last registry build, then we can safely re-cache it.
+      if ($file && isset($files[$file]) && !in_array($file, $parsed_files, TRUE)) {
+        $unchanged_resources[$key] = $file;
+      }
+    }
+  }
+  catch (Exception $e) {
+    $transaction->rollback();
+    watchdog_exception('registry', $e);
+    throw $e;
+  }
+
+  module_implements('', FALSE, TRUE);
+  _registry_check_code(REGISTRY_RESET_LOOKUP_CACHE);
+
+  // During the next run in this request, don't bother re-checking existing
+  // files.
+  $check_existing_files = FALSE;
+
+  // We have some unchanged resources, warm up the cache - no need to pay
+  // for looking them up again.
+  if (count($unchanged_resources) > 0) {
+    cache_set('lookup_cache', $unchanged_resources, 'cache_bootstrap');
+  }
+}
+
+/**
+ * Return the list of files in registry_file
+ */
+function registry_get_parsed_files() {
+  $files = array();
+  // We want the result as a keyed array.
+  $files = db_query("SELECT * FROM {registry_file}")->fetchAllAssoc('filename', PDO::FETCH_ASSOC);
+  return $files;
+}
+
+/**
+ * Parse all changed files and save their interface and class listings.
+ *
+ * Parse all files that have changed since the registry was last built, and save
+ * their interface and class listings.
+ *
+ * @param $files
+ *  The list of files to check and parse.
+ */
+function _registry_parse_files($files) {
+  $parsed_files = array();
+  foreach ($files as $filename => $file) {
+    if (file_exists($filename)) {
+      $hash = hash_file('sha256', $filename);
+      if (empty($file['hash']) || $file['hash'] != $hash) {
+        $file['hash'] = $hash;
+        $parsed_files[$filename] = $file;
+      }
+    }
+  }
+  foreach ($parsed_files as $filename => $file) {
+    _registry_parse_file($filename, file_get_contents($filename), $file['module'], $file['weight']);
+    db_merge('registry_file')
+      ->key(array('filename' => $filename))
+      ->fields(array(
+        'hash' => $file['hash'],
+      ))
+      ->execute();
+  }
+  return array_keys($parsed_files);
+}
+
+/**
+ * Parse a file and save its interface and class listings.
+ *
+ * @param $filename
+ *   Name of the file we are going to parse.
+ * @param $contents
+ *   Contents of the file we are going to parse as a string.
+ * @param $module
+ *   (optional) Name of the module this file belongs to.
+ * @param $weight
+ *   (optional) Weight of the module.
+ */
+function _registry_parse_file($filename, $contents, $module = '', $weight = 0) {
+  if (preg_match_all('/^\s*(?:abstract|final)?\s*(class|interface|trait)\s+([a-zA-Z0-9_]+)/m', $contents, $matches)) {
+    foreach ($matches[2] as $key => $name) {
+      db_merge('registry')
+        ->key(array(
+          'name' => $name,
+          'type' => $matches[1][$key],
+        ))
+        ->fields(array(
+          'filename' => $filename,
+          'module' => $module,
+          'weight' => $weight,
+        ))
+        ->execute();
+    }
+    // Delete any resources for this file where the name is not in the list
+    // we just merged in.
+    db_delete('registry')
+      ->condition('filename', $filename)
+      ->condition('name', $matches[2], 'NOT IN')
+      ->execute();
+  }
+}
+
+/**
+ * @} End of "defgroup registry".
+ */