Declarative content scripts: Browser-side: per-extension shared memory regions (lazily loaded)

chrome/browser/extensions/shared_user_script_master.h

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_EXTENSIONS_SHARED_USER_SCRIPT_MASTER_H_
+#define CHROME_BROWSER_EXTENSIONS_SHARED_USER_SCRIPT_MASTER_H_
+
+#include <set>
+
+#include "base/scoped_observer.h"
+#include "chrome/browser/extensions/user_script_loader.h"
+#include "extensions/browser/extension_registry_observer.h"
+#include "extensions/common/extension.h"
+#include "extensions/common/user_script.h"
+
+namespace content {
+class BrowserContext;
+}
+
+class Profile;
+
+namespace extensions {
+
+class ExtensionRegistry;
+
+// Manages statically-defined user scripts for all extensions. Owns a
+// UserScriptLoader to which file loading and shared memory management
+// operations are delegated.
+class SharedUserScriptMaster : public ExtensionRegistryObserver {
+ public:
+  explicit SharedUserScriptMaster(Profile* profile);
+  virtual ~SharedUserScriptMaster();
+
+  // Provides access to loader state method: scripts_ready().
+  bool scripts_ready() const { return loader_.scripts_ready(); }
+
+ private:
+  // ExtensionRegistryObserver implementation.
+  virtual void OnExtensionLoaded(content::BrowserContext* browser_context,
+                                 const Extension* extension) OVERRIDE;
+  virtual void OnExtensionUnloaded(
+      content::BrowserContext* browser_context,
+      const Extension* extension,
+      UnloadedExtensionInfo::Reason reason) OVERRIDE;
+
+  // Gets an extension's scripts' metadata; i.e., gets a list of UserScript
+  // objects that contains script info, but not the contents of the scripts.
+  const std::set<UserScript> GetScriptsMetadata(const Extension* extension);
+
+  // Script loader that handles loading contents of scripts into shared memory
+  // and notifying renderers of scripts in shared memory.
+  UserScriptLoader loader_;
+
+  // The profile for which the scripts managed here are installed.
+  Profile* profile_;
+
+  ScopedObserver<ExtensionRegistry, ExtensionRegistryObserver>
+      extension_registry_observer_;
+
+  DISALLOW_COPY_AND_ASSIGN(SharedUserScriptMaster);
+};
+
+}  // namespace extensions
+
+#endif  // CHROME_BROWSER_EXTENSIONS_SHARED_USER_SCRIPT_MASTER_H_