src/objects/api-callbacks.h

// Copyright 2018 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 V8_OBJECTS_API_CALLBACKS_H_
#define V8_OBJECTS_API_CALLBACKS_H_

#include "src/objects.h"

// Has to be the last include (doesn't have include guards):
#include "src/objects/object-macros.h"

namespace v8 {
namespace internal {

// An accessor must have a getter, but can have no setter.
//
// When setting a property, V8 searches accessors in prototypes.
// If an accessor was found and it does not have a setter,
// the request is ignored.
//
// If the accessor in the prototype has the READ_ONLY property attribute, then
// a new value is added to the derived object when the property is set.
// This shadows the accessor in the prototype.
class AccessorInfo : public Struct {
 public:
  DECL_ACCESSORS(name, Name)
  DECL_INT_ACCESSORS(flags)
  DECL_ACCESSORS(expected_receiver_type, Object)
  // This directly points at a foreign C function to be used from the runtime.
  DECL_ACCESSORS(getter, Object)
  inline bool has_getter();
  DECL_ACCESSORS(setter, Object)
  inline bool has_setter();
  // This either points at the same as above, or a trampoline in case we are
  // running with the simulator. Use these entries from generated code.
  DECL_ACCESSORS(js_getter, Object)
  DECL_ACCESSORS(data, Object)

  static Address redirect(Address address, AccessorComponent component);
  Address redirected_getter() const;

  // Dispatched behavior.
  DECL_PRINTER(AccessorInfo)

  DECL_BOOLEAN_ACCESSORS(all_can_read)
  DECL_BOOLEAN_ACCESSORS(all_can_write)
  DECL_BOOLEAN_ACCESSORS(is_special_data_property)
  DECL_BOOLEAN_ACCESSORS(replace_on_access)
  DECL_BOOLEAN_ACCESSORS(is_sloppy)
  DECL_BOOLEAN_ACCESSORS(has_no_side_effect)

  // The property attributes used when an API object template is instantiated
  // for the first time. Changing of this value afterwards does not affect
  // the actual attributes of a property.
  inline PropertyAttributes initial_property_attributes() const;
  inline void set_initial_property_attributes(PropertyAttributes attributes);

  // Checks whether the given receiver is compatible with this accessor.
  static bool IsCompatibleReceiverMap(Handle<AccessorInfo> info,
                                      Handle<Map> map);
  inline bool IsCompatibleReceiver(Object* receiver);

  DECL_CAST(AccessorInfo)

  // Dispatched behavior.
  DECL_VERIFIER(AccessorInfo)

  // Append all descriptors to the array that are not already there.
  // Return number added.
  static int AppendUnique(Isolate* isolate, Handle<Object> descriptors,
                          Handle<FixedArray> array, int valid_descriptors);

// Layout description.
#define ACCESSOR_INFO_FIELDS(V)                \
  V(kNameOffset, kPointerSize)                 \
  V(kFlagsOffset, kPointerSize)                \
  V(kExpectedReceiverTypeOffset, kPointerSize) \
  V(kSetterOffset, kPointerSize)               \
  V(kGetterOffset, kPointerSize)               \
  V(kJsGetterOffset, kPointerSize)             \
  V(kDataOffset, kPointerSize)                 \
  V(kSize, 0)

  DEFINE_FIELD_OFFSET_CONSTANTS(HeapObject::kHeaderSize, ACCESSOR_INFO_FIELDS)
#undef ACCESSOR_INFO_FIELDS

 private:
  inline bool HasExpectedReceiverType();

// Bit positions in |flags|.
#define ACCESSOR_INFO_FLAGS_BIT_FIELDS(V, _) \
  V(AllCanReadBit, bool, 1, _)               \
  V(AllCanWriteBit, bool, 1, _)              \
  V(IsSpecialDataPropertyBit, bool, 1, _)    \
  V(IsSloppyBit, bool, 1, _)                 \
  V(ReplaceOnAccessBit, bool, 1, _)          \
  V(HasNoSideEffectBit, bool, 1, _)          \
  V(InitialAttributesBits, PropertyAttributes, 3, _)

  DEFINE_BIT_FIELDS(ACCESSOR_INFO_FLAGS_BIT_FIELDS)
#undef ACCESSOR_INFO_FLAGS_BIT_FIELDS

  DISALLOW_IMPLICIT_CONSTRUCTORS(AccessorInfo);
};

class AccessCheckInfo : public Struct {
 public:
  DECL_ACCESSORS(callback, Object)
  DECL_ACCESSORS(named_interceptor, Object)
  DECL_ACCESSORS(indexed_interceptor, Object)
  DECL_ACCESSORS(data, Object)

  DECL_CAST(AccessCheckInfo)

  // Dispatched behavior.
  DECL_PRINTER(AccessCheckInfo)
  DECL_VERIFIER(AccessCheckInfo)

  static AccessCheckInfo* Get(Isolate* isolate, Handle<JSObject> receiver);

  static const int kCallbackOffset = HeapObject::kHeaderSize;
  static const int kNamedInterceptorOffset = kCallbackOffset + kPointerSize;
  static const int kIndexedInterceptorOffset =
      kNamedInterceptorOffset + kPointerSize;
  static const int kDataOffset = kIndexedInterceptorOffset + kPointerSize;
  static const int kSize = kDataOffset + kPointerSize;

 private:
  DISALLOW_IMPLICIT_CONSTRUCTORS(AccessCheckInfo);
};

class InterceptorInfo : public Struct {
 public:
  DECL_ACCESSORS(getter, Object)
  DECL_ACCESSORS(setter, Object)
  DECL_ACCESSORS(query, Object)
  DECL_ACCESSORS(descriptor, Object)
  DECL_ACCESSORS(deleter, Object)
  DECL_ACCESSORS(enumerator, Object)
  DECL_ACCESSORS(definer, Object)
  DECL_ACCESSORS(data, Object)
  DECL_BOOLEAN_ACCESSORS(can_intercept_symbols)
  DECL_BOOLEAN_ACCESSORS(all_can_read)
  DECL_BOOLEAN_ACCESSORS(non_masking)
  DECL_BOOLEAN_ACCESSORS(is_named)
  DECL_BOOLEAN_ACCESSORS(has_no_side_effect)

  inline int flags() const;
  inline void set_flags(int flags);

  DECL_CAST(InterceptorInfo)

  // Dispatched behavior.
  DECL_PRINTER(InterceptorInfo)
  DECL_VERIFIER(InterceptorInfo)

  static const int kGetterOffset = HeapObject::kHeaderSize;
  static const int kSetterOffset = kGetterOffset + kPointerSize;
  static const int kQueryOffset = kSetterOffset + kPointerSize;
  static const int kDescriptorOffset = kQueryOffset + kPointerSize;
  static const int kDeleterOffset = kDescriptorOffset + kPointerSize;
  static const int kEnumeratorOffset = kDeleterOffset + kPointerSize;
  static const int kDefinerOffset = kEnumeratorOffset + kPointerSize;
  static const int kDataOffset = kDefinerOffset + kPointerSize;
  static const int kFlagsOffset = kDataOffset + kPointerSize;
  static const int kSize = kFlagsOffset + kPointerSize;

  static const int kCanInterceptSymbolsBit = 0;
  static const int kAllCanReadBit = 1;
  static const int kNonMasking = 2;
  static const int kNamed = 3;
  static const int kHasNoSideEffect = 4;

 private:
  DISALLOW_IMPLICIT_CONSTRUCTORS(InterceptorInfo);
};

class CallHandlerInfo : public Tuple3 {
 public:
  DECL_ACCESSORS(callback, Object)
  DECL_ACCESSORS(js_callback, Object)
  DECL_ACCESSORS(data, Object)

  DECL_CAST(CallHandlerInfo)

  inline bool IsSideEffectFreeCallHandlerInfo() const;
  inline bool IsSideEffectCallHandlerInfo() const;
  inline void SetNextCallHasNoSideEffect();
  // Returns whether or not the next call can be side effect free.
  // Calling this will change the state back to having a side effect.
  inline bool NextCallHasNoSideEffect();

  // Dispatched behavior.
  DECL_PRINTER(CallHandlerInfo)
  DECL_VERIFIER(CallHandlerInfo)

  Address redirected_callback() const;

  static const int kCallbackOffset = kValue1Offset;
  static const int kJsCallbackOffset = kValue2Offset;
  static const int kDataOffset = kValue3Offset;

 private:
  DISALLOW_IMPLICIT_CONSTRUCTORS(CallHandlerInfo);
};

}  // namespace internal
}  // namespace v8

#include "src/objects/object-macros-undef.h"

#endif  // V8_OBJECTS_API_CALLBACKS_H_