// Copyright (c) 2012 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_RENDERER_EXTENSIONS_USER_SCRIPT_SCHEDULER_H_ #define CHROME_RENDERER_EXTENSIONS_USER_SCRIPT_SCHEDULER_H_ #include <map> #include <queue> #include "base/memory/linked_ptr.h" #include "base/memory/weak_ptr.h" #include "extensions/common/user_script.h" class RenderView; struct ExtensionMsg_ExecuteCode_Params; namespace blink { class WebFrame; } namespace extensions { class Dispatcher; // Implements support for injecting scripts at different times in the document // loading process. The different possible time are described in // UserScript::RunLocation. // // Currently, determining idleness is simple: it is whichever of the following // happens first: // // a) When the initial DOM for a page is complete + kUserScriptIdleTimeout, // b) or when the page has completely loaded including all subresources. // // The intent of this mechanism is to prevent user scripts from slowing down // fast pages (run after load), while still allowing them to run relatively // timely for pages with lots of slow subresources. // // NOTE: this class does not inherit from RenderViewObserver on purpose. The // reason is that this object is per frame, and a frame can move across // RenderViews thanks to adoptNode. So we have each RenderView's // ExtensionHelper proxy these calls to the renderer process' Dispatcher, // which contains the mapping from WebFrame to us. class UserScriptScheduler { public: UserScriptScheduler(blink::WebFrame* frame, Dispatcher* dispatcher); ~UserScriptScheduler(); void ExecuteCode(const ExtensionMsg_ExecuteCode_Params& params); void DidCreateDocumentElement(); void DidFinishDocumentLoad(); void DidFinishLoad(); void DidStartProvisionalLoad(); private: typedef std::queue<linked_ptr<ExtensionMsg_ExecuteCode_Params> > ExecutionQueue; // Run user scripts, except if they've already run for this frame, or the // frame has been destroyed. void MaybeRun(); // Backend for the IPC Message ExecuteCode in addition to being used // internally. void ExecuteCodeImpl(const ExtensionMsg_ExecuteCode_Params& params); // Get all child frames of parent_frame, returned by frames_vector. bool GetAllChildFrames(blink::WebFrame* parent_frame, std::vector<blink::WebFrame*>* frames_vector) const; // Call to signify thet the idle timeout has expired. void IdleTimeout(); base::WeakPtrFactory<UserScriptScheduler> weak_factory_; // The Frame we will run scripts in. blink::WebFrame* frame_; // The current location in the document loading process. // Will be UserScript::UNDEFINED if it is before any scripts should be run. UserScript::RunLocation current_location_; // Whether we have already run the idle scripts. bool has_run_idle_; // This is only used if we're for the main frame. std::map<UserScript::RunLocation, ExecutionQueue> pending_execution_map_; Dispatcher* dispatcher_; }; } // namespace extensions #endif // CHROME_RENDERER_EXTENSIONS_USER_SCRIPT_SCHEDULER_H_