v8-microtask-queue.h

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// Copyright 2021 the V8 project 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 INCLUDE_V8_MICROTASKS_QUEUE_H_
#define INCLUDE_V8_MICROTASKS_QUEUE_H_
 
#include <stddef.h>
 
#include <memory>
 
#include "cppgc/macros.h"
#include "v8-local-handle.h"  // NOLINT(build/include_directory)
#include "v8-microtask.h"     // NOLINT(build/include_directory)
#include "v8config.h"         // NOLINT(build/include_directory)
 
#ifdef V8_CPPGC_MICROTASK_QUEUE
#include "cppgc/garbage-collected.h"
#include "cppgc/name-provider.h"
#endif  // V8_CPPGC_MICROTASK_QUEUE
 
namespace v8 {
 
class Function;
 
namespace internal {
class Isolate;
class MicrotaskQueue;
}  // namespace internal
 
class V8_EXPORT MicrotaskQueue
#ifdef V8_CPPGC_MICROTASK_QUEUE
    : public cppgc::GarbageCollected<MicrotaskQueue>,
      public cppgc::NameProvider
#endif  // V8_CPPGC_MICROTASK_QUEUE
{
 public:
#ifdef V8_CPPGC_MICROTASK_QUEUE
  static MicrotaskQueue* New(Isolate* isolate,
                             MicrotasksPolicy policy = MicrotasksPolicy::kAuto);
  virtual void Trace(cppgc::Visitor* visitor) const {}
#else
  V8_DEPRECATE_SOON(
      "Use MicrotaskQueue allocated in cppgc, "
      "see gn flag: v8_cppgc_microtask_queue.")
  static std::unique_ptr<MicrotaskQueue> New(
      Isolate* isolate, MicrotasksPolicy policy = MicrotasksPolicy::kAuto);
#endif  // V8_CPPGC_MICROTASK_QUEUE
 
  virtual ~MicrotaskQueue() = default;
 
  virtual void EnqueueMicrotask(Isolate* isolate,
                                Local<Function> microtask) = 0;
 
  V8_DEPRECATE_SOON("Use the MicrotaskCallbackWithData overload instead")
  virtual void EnqueueMicrotask(v8::Isolate* isolate,
                                MicrotaskCallback callback,
                                void* data = nullptr) = 0;
  virtual void EnqueueMicrotask(v8::Isolate* isolate,
                                MicrotaskCallbackWithData callback,
                                v8::Local<v8::Data> data) = 0;
 
  virtual void AddMicrotasksCompletedCallback(
      MicrotasksCompletedCallbackWithData callback, void* data = nullptr) = 0;
 
  virtual void RemoveMicrotasksCompletedCallback(
      MicrotasksCompletedCallbackWithData callback, void* data = nullptr) = 0;
 
  virtual void PerformCheckpoint(Isolate* isolate) = 0;
 
  virtual bool IsRunningMicrotasks() const = 0;
 
  virtual int GetMicrotasksScopeDepth() const = 0;
 
  MicrotaskQueue(const MicrotaskQueue&) = delete;
  MicrotaskQueue& operator=(const MicrotaskQueue&) = delete;
 
 private:
  friend class internal::MicrotaskQueue;
  MicrotaskQueue() = default;
};
 
class V8_EXPORT V8_NODISCARD MicrotasksScope {
  CPPGC_STACK_ALLOCATED();
 
 public:
  enum Type { kRunMicrotasks, kDoNotRunMicrotasks };
 
  MicrotasksScope(Local<Context> context, Type type);
  MicrotasksScope(Isolate* isolate, MicrotaskQueue* microtask_queue, Type type);
  ~MicrotasksScope();
 
  static void PerformCheckpoint(Isolate* isolate);
 
  static int GetCurrentDepth(Isolate* isolate);
 
  static bool IsRunningMicrotasks(Isolate* isolate);
 
  // Prevent copying.
  MicrotasksScope(const MicrotasksScope&) = delete;
  MicrotasksScope& operator=(const MicrotasksScope&) = delete;
 
 private:
  internal::Isolate* const i_isolate_;
  internal::MicrotaskQueue* const microtask_queue_;
  bool run_;
};
 
}  // namespace v8
 
#endif  // INCLUDE_V8_MICROTASKS_QUEUE_H_