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The C and C++ Include Header Files

/usr/include/node/v8-weak-callback-info.h


$ cat -n /usr/include/node/v8-weak-callback-info.h

     1	// Copyright 2021 the V8 project 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 INCLUDE_V8_WEAK_CALLBACK_INFO_H_
     6	#define INCLUDE_V8_WEAK_CALLBACK_INFO_H_
     7	
     8	#include "v8config.h"  // NOLINT(build/include_directory)
     9	
    10	namespace v8 {
    11	
    12	class Isolate;
    13	
    14	namespace api_internal {
    15	V8_EXPORT void InternalFieldOutOfBounds(int index);
    16	}  // namespace api_internal
    17	
    18	static const int kInternalFieldsInWeakCallback = 2;
    19	static const int kEmbedderFieldsInWeakCallback = 2;
    20	
    21	template <typename T>
    22	class WeakCallbackInfo {
    23	 public:
    24	  using Callback = void (*)(const WeakCallbackInfo<T>& data);
    25	
    26	  WeakCallbackInfo(Isolate* isolate, T* parameter,
    27	                   void* embedder_fields[kEmbedderFieldsInWeakCallback],
    28	                   Callback* callback)
    29	      : isolate_(isolate), parameter_(parameter), callback_(callback) {
    30	    for (int i = 0; i < kEmbedderFieldsInWeakCallback; ++i) {
    31	      embedder_fields_[i] = embedder_fields[i];
    32	    }
    33	  }
    34	
    35	  V8_INLINE Isolate* GetIsolate() const { return isolate_; }
    36	  V8_INLINE T* GetParameter() const { return parameter_; }
    37	  V8_INLINE void* GetInternalField(int index) const;
    38	
    39	  // When first called, the embedder MUST Reset() the Global which triggered the
    40	  // callback. The Global itself is unusable for anything else. No v8 other api
    41	  // calls may be called in the first callback. Should additional work be
    42	  // required, the embedder must set a second pass callback, which will be
    43	  // called after all the initial callbacks are processed.
    44	  // Calling SetSecondPassCallback on the second pass will immediately crash.
    45	  void SetSecondPassCallback(Callback callback) const { *callback_ = callback; }
    46	
    47	 private:
    48	  Isolate* isolate_;
    49	  T* parameter_;
    50	  Callback* callback_;
    51	  void* embedder_fields_[kEmbedderFieldsInWeakCallback];
    52	};
    53	
    54	/**
    55	 * Weakness type for weak handles.
    56	 */
    57	enum class WeakCallbackType {
    58	  /**
    59	   * Passes a user-defined void* parameter back to the callback.
    60	   */
    61	  kParameter,
    62	  /**
    63	   * Passes the first two internal fields of the object back to the callback.
    64	   */
    65	  kInternalFields,
    66	  /**
    67	   * Passes a user-defined void* parameter back to the callback. Will do so
    68	   * before the object is actually reclaimed, allowing it to be resurrected. In
    69	   * this case it is not possible to set a second-pass callback.
    70	   */
    71	  kFinalizer V8_ENUM_DEPRECATED("Resurrecting finalizers are deprecated "
    72	                                "and will not be supported going forward.")
    73	};
    74	
    75	template <class T>
    76	void* WeakCallbackInfo<T>::GetInternalField(int index) const {
    77	#ifdef V8_ENABLE_CHECKS
    78	  if (index < 0 || index >= kEmbedderFieldsInWeakCallback) {
    79	    api_internal::InternalFieldOutOfBounds(index);
    80	  }
    81	#endif
    82	  return embedder_fields_[index];
    83	}
    84	
    85	}  // namespace v8
    86	
    87	#endif  // INCLUDE_V8_WEAK_CALLBACK_INFO_H_