v8-template.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_TEMPLATE_H_
#define INCLUDE_V8_TEMPLATE_H_
 
#include <cstddef>
#include <string_view>
 
#include "v8-data.h"               // NOLINT(build/include_directory)
#include "v8-exception.h"          // NOLINT(build/include_directory)
#include "v8-function-callback.h"  // NOLINT(build/include_directory)
#include "v8-local-handle.h"       // NOLINT(build/include_directory)
#include "v8-memory-span.h"        // NOLINT(build/include_directory)
#include "v8-object.h"             // NOLINT(build/include_directory)
#include "v8config.h"              // NOLINT(build/include_directory)
 
namespace v8 {
 
class CFunction;
class FunctionTemplate;
class ObjectTemplate;
class Signature;
 
// --- Templates ---
 
#define V8_INTRINSICS_LIST(F)                                 \
  F(ArrayProto_entries, array_entries_iterator)               \
  F(ArrayProto_forEach, array_for_each_iterator)              \
  F(ArrayProto_keys, array_keys_iterator)                     \
  F(ArrayProto_values, array_values_iterator)                 \
  F(ArrayPrototype, initial_array_prototype)                  \
  F(AsyncIteratorPrototype, initial_async_iterator_prototype) \
  F(ErrorPrototype, initial_error_prototype)                  \
  F(IteratorPrototype, initial_iterator_prototype)            \
  F(MapIteratorPrototype, initial_map_iterator_prototype)     \
  F(ObjProto_valueOf, object_value_of_function)               \
  F(SetIteratorPrototype, initial_set_iterator_prototype)
 
enum Intrinsic {
#define V8_DECL_INTRINSIC(name, iname) k##name,
  V8_INTRINSICS_LIST(V8_DECL_INTRINSIC)
#undef V8_DECL_INTRINSIC
};

class V8_EXPORT Template : public Data {
 public:
  void Set(Local<Name> name, Local<Data> value,
           PropertyAttribute attributes = None);
  void SetPrivate(Local<Private> name, Local<Data> value,
                  PropertyAttribute attributes = None);
  V8_INLINE void Set(Isolate* isolate, const char* name, Local<Data> value,
                     PropertyAttribute attributes = None);

  void SetAccessorProperty(
      Local<Name> name,
      Local<FunctionTemplate> getter = Local<FunctionTemplate>(),
      Local<FunctionTemplate> setter = Local<FunctionTemplate>(),
      PropertyAttribute attribute = None);

  void SetNativeDataProperty(
      Local<Name> name, AccessorNameGetterCallback getter,
      AccessorNameSetterCallback setter = nullptr,
      Local<Value> data = Local<Value>(), PropertyAttribute attribute = None,
      SideEffectType getter_side_effect_type = SideEffectType::kHasSideEffect,
      SideEffectType setter_side_effect_type = SideEffectType::kHasSideEffect);

  void SetLazyDataProperty(
      Local<Name> name, AccessorNameGetterCallback getter,
      Local<Value> data = Local<Value>(), PropertyAttribute attribute = None,
      SideEffectType getter_side_effect_type = SideEffectType::kHasSideEffect,
      SideEffectType setter_side_effect_type = SideEffectType::kHasSideEffect);

  void SetIntrinsicDataProperty(Local<Name> name, Intrinsic intrinsic,
                                PropertyAttribute attribute = None);
 
 private:
  Template();
 
  friend class ObjectTemplate;
  friend class FunctionTemplate;
};

enum class Intercepted : uint8_t { kNo = 0, kYes = 1 };

using NamedPropertyGetterCallback = Intercepted (*)(
    Local<Name> property, const PropertyCallbackInfo<Value>& info);
// This variant will be deprecated soon.
//
// Use `info.GetReturnValue().Set()` to set the return value of the
// intercepted get request. If the property does not exist the callback should
// not set the result and must not produce side effects.
using GenericNamedPropertyGetterCallback =
    void (*)(Local<Name> property, const PropertyCallbackInfo<Value>& info);

using NamedPropertySetterCallback =
    Intercepted (*)(Local<Name> property, Local<Value> value,
                    const PropertyCallbackInfo<void>& info);
// This variant will be deprecated soon.
//
// Use `info.GetReturnValue()` to indicate whether the request was intercepted
// or not. If the setter successfully intercepts the request, i.e., if the
// request should not be further executed, call
// `info.GetReturnValue().Set(value)`. If the setter did not intercept the
// request, i.e., if the request should be handled as if no interceptor is
// present, do not not call `Set()` and do not produce side effects.
using GenericNamedPropertySetterCallback =
    void (*)(Local<Name> property, Local<Value> value,
             const PropertyCallbackInfo<Value>& info);

using NamedPropertyQueryCallback = Intercepted (*)(
    Local<Name> property, const PropertyCallbackInfo<Integer>& info);
// This variant will be deprecated soon.
//
// Use `info.GetReturnValue().Set(value)` to set the property attributes. The
// value is an integer encoding a `v8::PropertyAttribute`. If the property does
// not exist the callback should not set the result and must not produce side
// effects.
using GenericNamedPropertyQueryCallback =
    void (*)(Local<Name> property, const PropertyCallbackInfo<Integer>& info);

using NamedPropertyDeleterCallback = Intercepted (*)(
    Local<Name> property, const PropertyCallbackInfo<Boolean>& info);
// This variant will be deprecated soon.
//
// Use `info.GetReturnValue()` to indicate whether the request was intercepted
// or not. If the deleter successfully intercepts the request, i.e., if the
// request should not be further executed, call
// `info.GetReturnValue().Set(value)` with a boolean `value`. The `value` is
// used as the return value of `delete`. If the deleter does not intercept the
// request then it should not set the result and must not produce side effects.
using GenericNamedPropertyDeleterCallback =
    void (*)(Local<Name> property, const PropertyCallbackInfo<Boolean>& info);

using NamedPropertyEnumeratorCallback =
    void (*)(const PropertyCallbackInfo<Array>& info);
// This variant will be deprecated soon.
// This is just a renaming of the typedef.
using GenericNamedPropertyEnumeratorCallback = NamedPropertyEnumeratorCallback;

using NamedPropertyDefinerCallback =
    Intercepted (*)(Local<Name> property, const PropertyDescriptor& desc,
                    const PropertyCallbackInfo<void>& info);
// This variant will be deprecated soon.
//
// Use `info.GetReturnValue()` to indicate whether the request was intercepted
// or not. If the definer successfully intercepts the request, i.e., if the
// request should not be further executed, call
// `info.GetReturnValue().Set(value)`. If the definer did not intercept the
// request, i.e., if the request should be handled as if no interceptor is
// present, do not not call `Set()` and do not produce side effects.
using GenericNamedPropertyDefinerCallback =
    void (*)(Local<Name> property, const PropertyDescriptor& desc,
             const PropertyCallbackInfo<Value>& info);

using NamedPropertyDescriptorCallback = Intercepted (*)(
    Local<Name> property, const PropertyCallbackInfo<Value>& info);
// This variant will be deprecated soon.
//
// Use `info.GetReturnValue().Set()` to set the return value of the
// intercepted request. The return value must be an object that
// can be converted to a PropertyDescriptor, e.g., a `v8::Value` returned from
// `v8::Object::getOwnPropertyDescriptor`.
using GenericNamedPropertyDescriptorCallback =
    void (*)(Local<Name> property, const PropertyCallbackInfo<Value>& info);
 
// TODO(ishell): Rename IndexedPropertyXxxCallbackV2 back to
// IndexedPropertyXxxCallback once the old IndexedPropertyXxxCallback is
// removed.

using IndexedPropertyGetterCallbackV2 =
    Intercepted (*)(uint32_t index, const PropertyCallbackInfo<Value>& info);
// This variant will be deprecated soon.
using IndexedPropertyGetterCallback =
    void (*)(uint32_t index, const PropertyCallbackInfo<Value>& info);

using IndexedPropertySetterCallbackV2 = Intercepted (*)(
    uint32_t index, Local<Value> value, const PropertyCallbackInfo<void>& info);
// This variant will be deprecated soon.
using IndexedPropertySetterCallback =
    void (*)(uint32_t index, Local<Value> value,
             const PropertyCallbackInfo<Value>& info);

using IndexedPropertyQueryCallbackV2 =
    Intercepted (*)(uint32_t index, const PropertyCallbackInfo<Integer>& info);
// This variant will be deprecated soon.
using IndexedPropertyQueryCallback =
    void (*)(uint32_t index, const PropertyCallbackInfo<Integer>& info);

using IndexedPropertyDeleterCallbackV2 =
    Intercepted (*)(uint32_t index, const PropertyCallbackInfo<Boolean>& info);
// This variant will be deprecated soon.
using IndexedPropertyDeleterCallback =
    void (*)(uint32_t index, const PropertyCallbackInfo<Boolean>& info);

using IndexedPropertyEnumeratorCallback =
    void (*)(const PropertyCallbackInfo<Array>& info);

using IndexedPropertyDefinerCallbackV2 =
    Intercepted (*)(uint32_t index, const PropertyDescriptor& desc,
                    const PropertyCallbackInfo<void>& info);
// This variant will be deprecated soon.
using IndexedPropertyDefinerCallback =
    void (*)(uint32_t index, const PropertyDescriptor& desc,
             const PropertyCallbackInfo<Value>& info);

using IndexedPropertyDescriptorCallbackV2 =
    Intercepted (*)(uint32_t index, const PropertyCallbackInfo<Value>& info);
// This variant will be deprecated soon.
using IndexedPropertyDescriptorCallback =
    void (*)(uint32_t index, const PropertyCallbackInfo<Value>& info);

using AccessCheckCallback = bool (*)(Local<Context> accessing_context,
                                     Local<Object> accessed_object,
                                     Local<Value> data);
 
enum class ConstructorBehavior { kThrow, kAllow };

class V8_EXPORT FunctionTemplate : public Template {
 public:
  static Local<FunctionTemplate> New(
      Isolate* isolate, FunctionCallback callback = nullptr,
      Local<Value> data = Local<Value>(),
      Local<Signature> signature = Local<Signature>(), int length = 0,
      ConstructorBehavior behavior = ConstructorBehavior::kAllow,
      SideEffectType side_effect_type = SideEffectType::kHasSideEffect,
      const CFunction* c_function = nullptr, uint16_t instance_type = 0,
      uint16_t allowed_receiver_instance_type_range_start = 0,
      uint16_t allowed_receiver_instance_type_range_end = 0);

  static Local<FunctionTemplate> NewWithCFunctionOverloads(
      Isolate* isolate, FunctionCallback callback = nullptr,
      Local<Value> data = Local<Value>(),
      Local<Signature> signature = Local<Signature>(), int length = 0,
      ConstructorBehavior behavior = ConstructorBehavior::kAllow,
      SideEffectType side_effect_type = SideEffectType::kHasSideEffect,
      const MemorySpan<const CFunction>& c_function_overloads = {});

  static Local<FunctionTemplate> NewWithCache(
      Isolate* isolate, FunctionCallback callback,
      Local<Private> cache_property, Local<Value> data = Local<Value>(),
      Local<Signature> signature = Local<Signature>(), int length = 0,
      SideEffectType side_effect_type = SideEffectType::kHasSideEffect);

  V8_WARN_UNUSED_RESULT MaybeLocal<Function> GetFunction(
      Local<Context> context);

  V8_WARN_UNUSED_RESULT MaybeLocal<Object> NewRemoteInstance();

  void SetCallHandler(
      FunctionCallback callback, Local<Value> data = Local<Value>(),
      SideEffectType side_effect_type = SideEffectType::kHasSideEffect,
      const MemorySpan<const CFunction>& c_function_overloads = {});

  void SetLength(int length);

  Local<ObjectTemplate> InstanceTemplate();

  void Inherit(Local<FunctionTemplate> parent);

  Local<ObjectTemplate> PrototypeTemplate();

  void SetPrototypeProviderTemplate(Local<FunctionTemplate> prototype_provider);

  void SetClassName(Local<String> name);

  void SetInterfaceName(Local<String> name);

  void SetExceptionContext(ExceptionContext context);

  void SetAcceptAnyReceiver(bool value);

  void ReadOnlyPrototype();

  void RemovePrototype();

  bool HasInstance(Local<Value> object);

  bool IsLeafTemplateForApiObject(v8::Local<v8::Value> value) const;

  void SealAndPrepareForPromotionToReadOnly();
 
  V8_INLINE static FunctionTemplate* Cast(Data* data);
 
 private:
  FunctionTemplate();
 
  static void CheckCast(Data* that);
  friend class Context;
  friend class ObjectTemplate;
};

enum class PropertyHandlerFlags {
  kNone = 0,

  kNonMasking = 1,

  kOnlyInterceptStrings = 1 << 1,

  kHasNoSideEffect = 1 << 2,

  kInternalNewCallbacksSignatures = 1 << 10,
};
 
struct NamedPropertyHandlerConfiguration {
 private:
  static constexpr PropertyHandlerFlags WithNewSignatureFlag(
      PropertyHandlerFlags flags) {
    return static_cast<PropertyHandlerFlags>(
        static_cast<int>(flags) |
        static_cast<int>(
            PropertyHandlerFlags::kInternalNewCallbacksSignatures));
  }
 
 public:
  NamedPropertyHandlerConfiguration(
      NamedPropertyGetterCallback getter,          //
      NamedPropertySetterCallback setter,          //
      NamedPropertyQueryCallback query,            //
      NamedPropertyDeleterCallback deleter,        //
      NamedPropertyEnumeratorCallback enumerator,  //
      NamedPropertyDefinerCallback definer,        //
      NamedPropertyDescriptorCallback descriptor,  //
      Local<Value> data = Local<Value>(),
      PropertyHandlerFlags flags = PropertyHandlerFlags::kNone)
      : getter(getter),
        setter(setter),
        query(query),
        deleter(deleter),
        enumerator(enumerator),
        definer(definer),
        descriptor(descriptor),
        data(data),
        flags(flags) {}
 
  explicit NamedPropertyHandlerConfiguration(
      NamedPropertyGetterCallback getter,
      NamedPropertySetterCallback setter = nullptr,
      NamedPropertyQueryCallback query = nullptr,
      NamedPropertyDeleterCallback deleter = nullptr,
      NamedPropertyEnumeratorCallback enumerator = nullptr,
      Local<Value> data = Local<Value>(),
      PropertyHandlerFlags flags = PropertyHandlerFlags::kNone)
      : getter(getter),
        setter(setter),
        query(query),
        deleter(deleter),
        enumerator(enumerator),
        definer(nullptr),
        descriptor(nullptr),
        data(data),
        flags(flags) {}
 
  NamedPropertyHandlerConfiguration(
      NamedPropertyGetterCallback getter,          //
      NamedPropertySetterCallback setter,          //
      NamedPropertyDescriptorCallback descriptor,  //
      NamedPropertyDeleterCallback deleter,        //
      NamedPropertyEnumeratorCallback enumerator,  //
      NamedPropertyDefinerCallback definer,        //
      Local<Value> data = Local<Value>(),
      PropertyHandlerFlags flags = PropertyHandlerFlags::kNone)
      : getter(getter),
        setter(setter),
        query(nullptr),
        deleter(deleter),
        enumerator(enumerator),
        definer(definer),
        descriptor(descriptor),
        data(data),
        flags(flags) {}
 
  NamedPropertyGetterCallback getter;
  NamedPropertySetterCallback setter;
  NamedPropertyQueryCallback query;
  NamedPropertyDeleterCallback deleter;
  NamedPropertyEnumeratorCallback enumerator;
  NamedPropertyDefinerCallback definer;
  NamedPropertyDescriptorCallback descriptor;
  Local<Value> data;
  PropertyHandlerFlags flags;
};
 
struct IndexedPropertyHandlerConfiguration {
 private:
  static constexpr PropertyHandlerFlags WithNewSignatureFlag(
      PropertyHandlerFlags flags) {
    return static_cast<PropertyHandlerFlags>(
        static_cast<int>(flags) |
        static_cast<int>(
            PropertyHandlerFlags::kInternalNewCallbacksSignatures));
  }
 
 public:
  IndexedPropertyHandlerConfiguration(
      IndexedPropertyGetterCallbackV2 getter,          //
      IndexedPropertySetterCallbackV2 setter,          //
      IndexedPropertyQueryCallbackV2 query,            //
      IndexedPropertyDeleterCallbackV2 deleter,        //
      IndexedPropertyEnumeratorCallback enumerator,    //
      IndexedPropertyDefinerCallbackV2 definer,        //
      IndexedPropertyDescriptorCallbackV2 descriptor,  //
      Local<Value> data = Local<Value>(),
      PropertyHandlerFlags flags = PropertyHandlerFlags::kNone)
      : getter(getter),
        setter(setter),
        query(query),
        deleter(deleter),
        enumerator(enumerator),
        definer(definer),
        descriptor(descriptor),
        data(data),
        flags(flags) {}
 
  explicit IndexedPropertyHandlerConfiguration(
      IndexedPropertyGetterCallbackV2 getter = nullptr,
      IndexedPropertySetterCallbackV2 setter = nullptr,
      IndexedPropertyQueryCallbackV2 query = nullptr,
      IndexedPropertyDeleterCallbackV2 deleter = nullptr,
      IndexedPropertyEnumeratorCallback enumerator = nullptr,
      Local<Value> data = Local<Value>(),
      PropertyHandlerFlags flags = PropertyHandlerFlags::kNone)
      : getter(getter),
        setter(setter),
        query(query),
        deleter(deleter),
        enumerator(enumerator),
        definer(nullptr),
        descriptor(nullptr),
        data(data),
        flags(flags) {}
 
  IndexedPropertyHandlerConfiguration(
      IndexedPropertyGetterCallbackV2 getter,
      IndexedPropertySetterCallbackV2 setter,
      IndexedPropertyDescriptorCallbackV2 descriptor,
      IndexedPropertyDeleterCallbackV2 deleter,
      IndexedPropertyEnumeratorCallback enumerator,
      IndexedPropertyDefinerCallbackV2 definer,
      Local<Value> data = Local<Value>(),
      PropertyHandlerFlags flags = PropertyHandlerFlags::kNone)
      : getter(getter),
        setter(setter),
        query(nullptr),
        deleter(deleter),
        enumerator(enumerator),
        definer(definer),
        descriptor(descriptor),
        data(data),
        flags(flags) {}
 
  IndexedPropertyGetterCallbackV2 getter;
  IndexedPropertySetterCallbackV2 setter;
  IndexedPropertyQueryCallbackV2 query;
  IndexedPropertyDeleterCallbackV2 deleter;
  IndexedPropertyEnumeratorCallback enumerator;
  IndexedPropertyDefinerCallbackV2 definer;
  IndexedPropertyDescriptorCallbackV2 descriptor;
  Local<Value> data;
  PropertyHandlerFlags flags;
};

class V8_EXPORT ObjectTemplate : public Template {
 public:
  static Local<ObjectTemplate> New(
      Isolate* isolate,
      Local<FunctionTemplate> constructor = Local<FunctionTemplate>());

  V8_WARN_UNUSED_RESULT MaybeLocal<Object> NewInstance(Local<Context> context);

  void SetHandler(const NamedPropertyHandlerConfiguration& configuration);

  void SetHandler(const IndexedPropertyHandlerConfiguration& configuration);

  void SetCallAsFunctionHandler(FunctionCallback callback,
                                Local<Value> data = Local<Value>());

  void MarkAsUndetectable();

  void SetAccessCheckCallback(AccessCheckCallback callback,
                              Local<Value> data = Local<Value>());

  void SetAccessCheckCallbackAndHandler(
      AccessCheckCallback callback,
      const NamedPropertyHandlerConfiguration& named_handler,
      const IndexedPropertyHandlerConfiguration& indexed_handler,
      Local<Value> data = Local<Value>());

  int InternalFieldCount() const;

  void SetInternalFieldCount(int value);

  bool IsImmutableProto() const;

  void SetImmutableProto();

  void SetCodeLike();
  bool IsCodeLike() const;
 
  V8_INLINE static ObjectTemplate* Cast(Data* data);
 
 private:
  ObjectTemplate();
 
  static void CheckCast(Data* that);
  friend class FunctionTemplate;
};

class V8_EXPORT DictionaryTemplate final {
 public:
  static Local<DictionaryTemplate> New(
      Isolate* isolate, MemorySpan<const std::string_view> names);

  V8_WARN_UNUSED_RESULT Local<Object> NewInstance(
      Local<Context> context, MemorySpan<MaybeLocal<Value>> property_values);
 
  V8_INLINE static DictionaryTemplate* Cast(Data* data);
 
 private:
  static void CheckCast(Data* that);
 
  DictionaryTemplate();
};

class V8_EXPORT Signature : public Data {
 public:
  static Local<Signature> New(
      Isolate* isolate,
      Local<FunctionTemplate> receiver = Local<FunctionTemplate>());
 
  V8_INLINE static Signature* Cast(Data* data);
 
 private:
  Signature();
 
  static void CheckCast(Data* that);
};
 
// --- Implementation ---
 
void Template::Set(Isolate* isolate, const char* name, Local<Data> value,
                   PropertyAttribute attributes) {
  Set(String::NewFromUtf8(isolate, name, NewStringType::kInternalized)
          .ToLocalChecked(),
      value, attributes);
}
 
FunctionTemplate* FunctionTemplate::Cast(Data* data) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(data);
#endif
  return reinterpret_cast<FunctionTemplate*>(data);
}
 
ObjectTemplate* ObjectTemplate::Cast(Data* data) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(data);
#endif
  return reinterpret_cast<ObjectTemplate*>(data);
}
 
DictionaryTemplate* DictionaryTemplate::Cast(Data* data) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(data);
#endif
  return reinterpret_cast<DictionaryTemplate*>(data);
}
 
Signature* Signature::Cast(Data* data) {
#ifdef V8_ENABLE_CHECKS
  CheckCast(data);
#endif
  return reinterpret_cast<Signature*>(data);
}
 
}  // namespace v8
 
#endif  // INCLUDE_V8_TEMPLATE_H_