1// Copyright (c) 2012 The Chromium Authors. All rights reserved. 2// Use of this source code is governed by a BSD-style license that can be 3// found in the LICENSE file. 4 5#ifndef CHROME_RENDERER_EXTENSIONS_USER_SCRIPT_SCHEDULER_H_ 6#define CHROME_RENDERER_EXTENSIONS_USER_SCRIPT_SCHEDULER_H_ 7 8#include <map> 9#include <queue> 10 11#include "base/memory/linked_ptr.h" 12#include "base/memory/weak_ptr.h" 13#include "extensions/common/user_script.h" 14 15class RenderView; 16struct ExtensionMsg_ExecuteCode_Params; 17 18namespace WebKit { 19class WebFrame; 20} 21 22namespace extensions { 23class Dispatcher; 24 25// Implements support for injecting scripts at different times in the document 26// loading process. The different possible time are described in 27// UserScript::RunLocation. 28// 29// Currently, determining idleness is simple: it is whichever of the following 30// happens first: 31// 32// a) When the initial DOM for a page is complete + kUserScriptIdleTimeout, 33// b) or when the page has completely loaded including all subresources. 34// 35// The intent of this mechanism is to prevent user scripts from slowing down 36// fast pages (run after load), while still allowing them to run relatively 37// timely for pages with lots of slow subresources. 38// 39// NOTE: this class does not inherit from RenderViewObserver on purpose. The 40// reason is that this object is per frame, and a frame can move across 41// RenderViews thanks to adoptNode. So we have each RenderView's 42// ExtensionHelper proxy these calls to the renderer process' Dispatcher, 43// which contains the mapping from WebFrame to us. 44class UserScriptScheduler { 45 public: 46 UserScriptScheduler(WebKit::WebFrame* frame, Dispatcher* dispatcher); 47 ~UserScriptScheduler(); 48 49 void ExecuteCode(const ExtensionMsg_ExecuteCode_Params& params); 50 void DidCreateDocumentElement(); 51 void DidFinishDocumentLoad(); 52 void DidFinishLoad(); 53 void DidStartProvisionalLoad(); 54 55 private: 56 typedef 57 std::queue<linked_ptr<ExtensionMsg_ExecuteCode_Params> > 58 ExecutionQueue; 59 60 // Run user scripts, except if they've already run for this frame, or the 61 // frame has been destroyed. 62 void MaybeRun(); 63 64 // Backend for the IPC Message ExecuteCode in addition to being used 65 // internally. 66 void ExecuteCodeImpl(const ExtensionMsg_ExecuteCode_Params& params); 67 68 // Get all child frames of parent_frame, returned by frames_vector. 69 bool GetAllChildFrames(WebKit::WebFrame* parent_frame, 70 std::vector<WebKit::WebFrame*>* frames_vector) const; 71 72 // Call to signify thet the idle timeout has expired. 73 void IdleTimeout(); 74 75 base::WeakPtrFactory<UserScriptScheduler> weak_factory_; 76 77 // The Frame we will run scripts in. 78 WebKit::WebFrame* frame_; 79 80 // The current location in the document loading process. 81 // Will be UserScript::UNDEFINED if it is before any scripts should be run. 82 UserScript::RunLocation current_location_; 83 84 // Whether we have already run the idle scripts. 85 bool has_run_idle_; 86 87 // This is only used if we're for the main frame. 88 std::map<UserScript::RunLocation, ExecutionQueue> pending_execution_map_; 89 90 Dispatcher* dispatcher_; 91}; 92 93} // namespace extensions 94 95#endif // CHROME_RENDERER_EXTENSIONS_USER_SCRIPT_SCHEDULER_H_ 96