dom/base/TimeoutHandler.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_dom_timeout_handler_h
   8 #define mozilla_dom_timeout_handler_h
   9
  10 #include "nsCOMPtr.h"
  11 #include "nsIGlobalObject.h"
  12 #include "nsISupports.h"
  13 #include "nsCycleCollectionParticipant.h"
  14 #include "nsString.h"
  15 #include "mozilla/Attributes.h"
  16 #include "mozilla/SourceLocation.h"
  17 #include "mozilla/dom/FunctionBinding.h"
  18
  19 namespace mozilla::dom {
  20
  21 /**
  22  * Utility class for implementing nsITimeoutHandlers, designed to be subclassed.
  23  */
  24 class TimeoutHandler : public nsISupports {
  25  public:
  26   MOZ_CAN_RUN_SCRIPT virtual bool Call(const char* /* unused */);
  27   // Append a UTF-8 string to aOutString that describes the callback function,
  28   // for use in logging or profiler markers.
  29   // The string contains the function name and its source location, if
  30   // available, in the following format:
  31   // "<functionName> (<sourceURL>:<lineNumber>:<columnNumber>)"
  32   virtual void GetDescription(nsACString& aOutString);
  33   virtual void MarkForCC() {}
  34
  35  protected:
  36   TimeoutHandler() = default;
  37   explicit TimeoutHandler(JSContext* aCx)
  38       : mCaller(JSCallingLocation::Get(aCx)) {}
  39
  40   virtual ~TimeoutHandler() = default;
  41
  42   // filename, line number and JS language version string of the
  43   // caller of setTimeout()
  44   const JSCallingLocation mCaller = {};
  45
  46  private:
  47   TimeoutHandler(const TimeoutHandler&) = delete;
  48   TimeoutHandler& operator=(const TimeoutHandler&) = delete;
  49   TimeoutHandler& operator=(const TimeoutHandler&&) = delete;
  50 };
  51
  52 class ScriptTimeoutHandler : public TimeoutHandler {
  53  public:
  54   NS_DECL_CYCLE_COLLECTING_ISUPPORTS
  55   NS_DECL_CYCLE_COLLECTION_CLASS(ScriptTimeoutHandler)
  56
  57   ScriptTimeoutHandler(JSContext* aCx, nsIGlobalObject* aGlobal,
  58                        const nsAString& aExpression);
  59
  60   MOZ_CAN_RUN_SCRIPT virtual bool Call(const char* /* unused */) override {
  61     return false;
  62   };
  63   virtual void GetDescription(nsACString& aOutString) override;
  64
  65  protected:
  66   virtual ~ScriptTimeoutHandler() = default;
  67
  68   nsCOMPtr<nsIGlobalObject> mGlobal;
  69   // The expression to evaluate or function to call. If mFunction is non-null
  70   // it should be used, else use mExpr.
  71   nsString mExpr;
  72 };
  73
  74 class CallbackTimeoutHandler final : public TimeoutHandler {
  75  public:
  76   NS_DECL_CYCLE_COLLECTING_ISUPPORTS
  77   NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(CallbackTimeoutHandler)
  78
  79   CallbackTimeoutHandler(JSContext* aCx, nsIGlobalObject* aGlobal,
  80                          Function* aFunction,
  81                          nsTArray<JS::Heap<JS::Value>>&& aArguments);
  82
  83   MOZ_CAN_RUN_SCRIPT virtual bool Call(const char* aExecutionReason) override;
  84   virtual void MarkForCC() override;
  85   virtual void GetDescription(nsACString& aOutString) override;
  86
  87   void ReleaseJSObjects();
  88
  89  private:
  90   virtual ~CallbackTimeoutHandler() { ReleaseJSObjects(); }
  91
  92   nsCOMPtr<nsIGlobalObject> mGlobal;
  93   RefPtr<Function> mFunction;
  94   nsTArray<JS::Heap<JS::Value>> mArgs;
  95 };
  96
  97 }  // namespace mozilla::dom
  98
  99 #endif  // mozilla_dom_timeout_handler_h