Namespaces
	api_internal

	base

	debug

	internal

	metrics

	platform

Data Structures
class	BackingStore

class	ArrayBuffer

class	ArrayBufferView

class	DataView

class	SharedArrayBuffer

class	FunctionCallbackInfo

struct	JitCodeEvent

struct	ModifyCodeGenerationFromStringsResult

class	Array

class	Map

class	Set

class	ExtensionConfiguration

class	Context

struct	WrapperDescriptor

struct	CppHeapCreateParams

class	CppHeap

class	JSVisitor

class	CustomSpaceStatisticsReceiver

class	Data

class	FixedArray

class	Date

class	StackFrame

class	StackTrace

class	EmbedderRootsHandler

class	EmbedderHeapTracer

class	EmbedderStateScope

class	Exception

class	TryCatch

class	Extension

class	External

class	CTypeInfo

struct	FastApiTypedArrayBase

struct	FastApiTypedArray

struct	FastApiArrayBufferView

struct	FastApiArrayBuffer

class	CFunctionInfo

struct	AnyCType

class	CFunction

struct	FastApiCallbackOptions

class	CTypeInfoBuilder

class	BasicTracedReference

class	Global

class	ReturnValue

class	PropertyCallbackInfo

class	Function

class	PersistentValueMapBase

class	V8

class	Local

class	ResourceConstraints

class	Isolate

class	JSON

class	Eternal

class	MaybeLocal

class	NonCopyablePersistentTraits

class	Persistent

class	PersistentBase

class	PersistentValueVector

class	Traced

class	TracedGlobal

class	TracedReference

class	HandleScope

class	EscapableHandleScope

class	SealHandleScope

class	Unlocker

class	Locker

class	Maybe

class	Maybe< void >

class	MemorySpan

class	ScriptOriginOptions

class	ScriptOrigin

class	Message

class	MicrotaskQueue

class	MicrotasksScope

class	Private

class	PropertyDescriptor

class	Object

class	PersistentValueMap

struct	CopyablePersistentTraits

class	PersistentHandleVisitor

class	Task

class	IdleTask

class	TaskRunner

class	JobDelegate

class	JobHandle

class	JobTask

class	ConvertableToTraceFormat

class	TracingController

class	PageAllocator

class	VirtualAddressSpace

class	ZoneBackingAllocator

class	HighAllocationThroughputObserver

class	Platform

class	NumberObject

class	BigIntObject

class	BooleanObject

class	StringObject

class	SymbolObject

class	Primitive

class	Boolean

class	PrimitiveArray

class	Name

class	String

class	ExternalResourceVisitor

class	Symbol

class	Number

class	Integer

class	Int32

class	Uint32

class	BigInt

struct	CpuProfileDeoptFrame

struct	CpuProfileDeoptInfo

class	CpuProfileNode

class	CpuProfile

class	DiscardedSamplesDelegate

class	CpuProfilingOptions

class	CpuProfiler

class	HeapGraphEdge

class	HeapGraphNode

class	OutputStream

class	HeapSnapshot

class	ActivityControl

class	AllocationProfile

class	EmbedderGraph

class	HeapProfiler

struct	HeapStatsUpdate

class	CodeEvent

class	CodeEventHandler

class	Promise

class	PromiseRejectMessage

class	Proxy

class	RegExp

class	ScriptOrModule

class	UnboundScript

class	UnboundModuleScript

class	Location

class	ModuleRequest

class	Module

class	Script

class	ScriptCompiler

class	StartupData

struct	SerializeInternalFieldsCallback

struct	DeserializeInternalFieldsCallback

class	SnapshotCreator

class	MeasureMemoryDelegate

class	SharedMemoryStatistics

class	HeapStatistics

class	HeapSpaceStatistics

class	HeapObjectStatistics

class	HeapCodeStatistics

class	Template

class	FunctionTemplate

struct	NamedPropertyHandlerConfiguration

struct	IndexedPropertyHandlerConfiguration

class	ObjectTemplate

class	Signature

class	AccessorSignature

struct	TracedGlobalTrait

class	TracedReferenceBase

class	TypedArray

class	Uint8Array

class	Uint8ClampedArray

class	Int8Array

class	Uint16Array

class	Int16Array

class	Uint32Array

class	Int32Array

class	Float32Array

class	Float64Array

class	BigInt64Array

class	BigUint64Array

struct	RegisterState

struct	SampleInfo

struct	MemoryRange

struct	JSEntryStub

struct	JSEntryStubs

class	Unwinder

class	GlobalValueMap

class	StdMapTraits

class	DefaultPersistentValueMapTraits

class	DefaultGlobalMapTraits

class	StdPersistentValueMap

class	StdGlobalValueMap

class	DefaultPersistentValueVectorTraits

class	ValueSerializer

class	ValueDeserializer

class	Value

struct	OwnedBuffer

class	CompiledWasmModule

class	WasmMemoryObject

class	WasmModuleObject

class	WasmStreaming

class	WasmModuleObjectBuilderStreaming

class	WeakCallbackInfo

Typedefs
using	BackingStoreDeleterCallback = void()(void data, size_t length, void *deleter_data)

using	JitCodeEventHandler = void()(const JitCodeEvent event)

using	GCCallback = void(*)(GCType type, GCCallbackFlags flags)

using	InterruptCallback = void()(Isolate isolate, void *data)

using	NearHeapLimitCallback = size_t()(void data, size_t current_heap_limit, size_t initial_heap_limit)

using	CounterLookupCallback = int ()(const char *name)

using	CreateHistogramCallback = void ()(const char *name, int min, int max, size_t buckets)

using	AddHistogramSampleCallback = void()(void histogram, int sample)

using	FatalErrorCallback = void()(const char location, const char *message)

using	OOMErrorCallback = void()(const char location, bool is_heap_oom)

using	MessageCallback = void(*)(Local< Message > message, Local< Value > data)

using	LogEventCallback = void()(const char name, int status)

using	AddCrashKeyCallback = void(*)(CrashKeyId id, const std::string &value)

using	BeforeCallEnteredCallback = void()(Isolate )

using	CallCompletedCallback = void()(Isolate )

using	AllowCodeGenerationFromStringsCallback = bool(*)(Local< Context > context, Local< String > source)

using	FailedAccessCheckCallback = void(*)(Local< Object > target, AccessType type, Local< Value > data)

using	ModifyCodeGenerationFromStringsCallback = ModifyCodeGenerationFromStringsResult(*)(Local< Context > context, Local< Value > source)

using	ModifyCodeGenerationFromStringsCallback2 = ModifyCodeGenerationFromStringsResult(*)(Local< Context > context, Local< Value > source, bool is_code_like)

using	ExtensionCallback = bool(*)(const FunctionCallbackInfo< Value > &)

using	AllowWasmCodeGenerationCallback = bool(*)(Local< Context > context, Local< String > source)

using	ApiImplementationCallback = void(*)(const FunctionCallbackInfo< Value > &)

using	WasmStreamingCallback = void(*)(const FunctionCallbackInfo< Value > &)

using	WasmLoadSourceMapCallback = Local< String >()(Isolate isolate, const char *name)

using	WasmSimdEnabledCallback = bool(*)(Local< Context > context)

using	WasmExceptionsEnabledCallback = bool(*)(Local< Context > context)

using	WasmDynamicTieringEnabledCallback = bool(*)(Local< Context > context)

using	SharedArrayBufferConstructorEnabledCallback = bool(*)(Local< Context > context)

using	HostImportModuleDynamicallyWithImportAssertionsCallback = MaybeLocal< Promise >(*)(Local< Context > context, Local< ScriptOrModule > referrer, Local< String > specifier, Local< FixedArray > import_assertions)

using	HostImportModuleDynamicallyCallback = MaybeLocal< Promise >(*)(Local< Context > context, Local< Data > host_defined_options, Local< Value > resource_name, Local< String > specifier, Local< FixedArray > import_assertions)

using	HostInitializeImportMetaObjectCallback = void(*)(Local< Context > context, Local< Module > module, Local< Object > meta)

using	HostCreateShadowRealmContextCallback = MaybeLocal< Context >(*)(Local< Context > initiator_context)

using	PrepareStackTraceCallback = MaybeLocal< Value >(*)(Local< Context > context, Local< Value > error, Local< Array > sites)

using	CFunctionBuilder = internal::CFunctionBuilder

using	FunctionCallback = void(*)(const FunctionCallbackInfo< Value > &info)

using	EntropySource = bool()(unsigned char buffer, size_t length)

using	ReturnAddressLocationResolver = uintptr_t(*)(uintptr_t return_addr_location)

using	DcheckErrorCallback = void()(const char file, int line, const char *message)

template<class T >
using	Handle = Local< T >

using	MicrotasksCompletedCallbackWithData = void()(Isolate , void *)

using	MicrotaskCallback = void()(void data)

using	AccessorGetterCallback = void(*)(Local< String > property, const PropertyCallbackInfo< Value > &info)

using	AccessorNameGetterCallback = void(*)(Local< Name > property, const PropertyCallbackInfo< Value > &info)

using	AccessorSetterCallback = void(*)(Local< String > property, Local< Value > value, const PropertyCallbackInfo< void > &info)

using	AccessorNameSetterCallback = void(*)(Local< Name > property, Local< Value > value, const PropertyCallbackInfo< void > &info)

template<class T >
using	UniquePersistent = Global< T >

using	PlatformSharedMemoryHandle = intptr_t

using	NativeObject = int void *

using	SnapshotObjectId = uint32_t

using	PromiseHook = void(*)(PromiseHookType type, Local< Promise > promise, Local< Value > parent)

using	PromiseRejectCallback = void(*)(PromiseRejectMessage message)

using	SerializeEmbedderFieldsCallback = SerializeInternalFieldsCallback

using	DeserializeEmbedderFieldsCallback = DeserializeInternalFieldsCallback

using	GenericNamedPropertyGetterCallback = void(*)(Local< Name > property, const PropertyCallbackInfo< Value > &info)

using	GenericNamedPropertySetterCallback = void(*)(Local< Name > property, Local< Value > value, const PropertyCallbackInfo< Value > &info)

using	GenericNamedPropertyQueryCallback = void(*)(Local< Name > property, const PropertyCallbackInfo< Integer > &info)

using	GenericNamedPropertyDeleterCallback = void(*)(Local< Name > property, const PropertyCallbackInfo< Boolean > &info)

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

using	GenericNamedPropertyDefinerCallback = void(*)(Local< Name > property, const PropertyDescriptor &desc, const PropertyCallbackInfo< Value > &info)

using	GenericNamedPropertyDescriptorCallback = void(*)(Local< Name > property, const PropertyCallbackInfo< Value > &info)

using	IndexedPropertyGetterCallback = void(*)(uint32_t index, const PropertyCallbackInfo< Value > &info)

using	IndexedPropertySetterCallback = void(*)(uint32_t index, Local< Value > value, const PropertyCallbackInfo< Value > &info)

using	IndexedPropertyQueryCallback = void(*)(uint32_t index, const PropertyCallbackInfo< Integer > &info)

using	IndexedPropertyDeleterCallback = void(*)(uint32_t index, const PropertyCallbackInfo< Boolean > &info)

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

using	IndexedPropertyDefinerCallback = void(*)(uint32_t index, const PropertyDescriptor &desc, const PropertyCallbackInfo< Value > &info)

using	IndexedPropertyDescriptorCallback = void(*)(uint32_t index, const PropertyCallbackInfo< Value > &info)

using	AccessCheckCallback = bool(*)(Local< Context > accessing_context, Local< Object > accessed_object, Local< Value > data)

typedef uintptr_t	PersistentContainerValue

Enumerations
enum class	ArrayBufferCreationMode { kInternalized , kExternalized }

enum	JitCodeEventOptions { kJitCodeEventDefault = 0 , kJitCodeEventEnumExisting = 1 }

enum	GCType { kGCTypeScavenge = 1 << 0 , kGCTypeMinorMarkCompact = 1 << 1 , kGCTypeMarkSweepCompact = 1 << 2 , kGCTypeIncrementalMarking = 1 << 3 , kGCTypeProcessWeakCallbacks = 1 << 4 , kGCTypeAll }

enum	GCCallbackFlags { kNoGCCallbackFlags = 0 , kGCCallbackFlagConstructRetainedObjectInfos = 1 << 1 , kGCCallbackFlagForced = 1 << 2 , kGCCallbackFlagSynchronousPhantomCallbackProcessing = 1 << 3 , kGCCallbackFlagCollectAllAvailableGarbage = 1 << 4 , kGCCallbackFlagCollectAllExternalMemory = 1 << 5 , kGCCallbackScheduleIdleGarbageCollection = 1 << 6 }

enum	LogEventStatus : int { kStart = 0 , kEnd = 1 , kStamp = 2 }

enum class	CrashKeyId { kIsolateAddress , kReadonlySpaceFirstPageAddress , kMapSpaceFirstPageAddress , kCodeSpaceFirstPageAddress , kDumpType }

enum	AccessType { ACCESS_GET , ACCESS_SET , ACCESS_HAS , ACCESS_DELETE , ACCESS_KEYS }

enum class	EmbedderStateTag : uint8_t { EMPTY = 0 , OTHER = 1 }

enum	RAILMode : unsigned { PERFORMANCE_RESPONSE , PERFORMANCE_ANIMATION , PERFORMANCE_IDLE , PERFORMANCE_LOAD }

enum class	MemoryPressureLevel { kNone , kModerate , kCritical }

enum class	MicrotasksPolicy { kExplicit , kScoped , kAuto }

enum	PropertyAttribute { None = 0 , ReadOnly = 1 << 0 , DontEnum = 1 << 1 , DontDelete = 1 << 2 }

enum	AccessControl { DEFAULT = 0 , ALL_CAN_READ = 1 , ALL_CAN_WRITE = 1 << 1 , PROHIBITS_OVERWRITING = 1 << 2 }

enum	PropertyFilter { ALL_PROPERTIES = 0 , ONLY_WRITABLE = 1 , ONLY_ENUMERABLE = 2 , ONLY_CONFIGURABLE = 4 , SKIP_STRINGS = 8 , SKIP_SYMBOLS = 16 }

enum class	SideEffectType { kHasSideEffect , kHasNoSideEffect , kHasSideEffectToReceiver }

enum class	KeyCollectionMode { kOwnOnly , kIncludePrototypes }

enum class	IndexFilter { kIncludeIndices , kSkipIndices }

enum class	KeyConversionMode { kConvertToString , kKeepNumbers , kNoNumbers }

enum class	IntegrityLevel { kFrozen , kSealed }

enum class	TaskPriority : uint8_t { kBestEffort , kUserVisible , kUserBlocking }

enum class	PagePermissions { kNoAccess , kRead , kReadWrite , kReadWriteExecute , kReadExecute }

enum class	NewStringType { kNormal , kInternalized }

enum	CpuProfilingMode { kLeafNodeLineNumbers , kCallerLineNumbers }

enum	CpuProfilingNamingMode { kStandardNaming , kDebugNaming }

enum	CpuProfilingLoggingMode { kLazyLogging , kEagerLogging }

enum class	CpuProfilingStatus { kStarted , kAlreadyStarted , kErrorTooManyProfilers }

enum	CodeEventType { kUnknownType }

enum class	PromiseHookType { kInit , kResolve , kBefore , kAfter }

enum	PromiseRejectEvent { kPromiseRejectWithNoHandler = 0 , kPromiseHandlerAddedAfterReject = 1 , kPromiseRejectAfterResolved = 2 , kPromiseResolveAfterResolved = 3 }

enum class	ScriptType { kClassic , kModule }

enum class	MeasureMemoryMode { kSummary , kDetailed }

enum class	MeasureMemoryExecution { kDefault , kEager , kLazy }

enum	Intrinsic

enum class	ConstructorBehavior { kThrow , kAllow }

enum class	PropertyHandlerFlags { kNone = 0 , kAllCanRead = 1 , kNonMasking = 1 << 1 , kOnlyInterceptStrings = 1 << 2 , kHasNoSideEffect = 1 << 3 }

enum	StateTag : int { JS , GC , PARSER , BYTECODE_COMPILER , COMPILER , OTHER , OTHER = 1 , EXTERNAL , ATOMICS_WAIT , IDLE }

enum	PersistentContainerCallbackType { kNotWeak , kWeakWithParameter , kWeakWithInternalFields }

enum class	WeakCallbackType { kParameter , kInternalFields , V8_ENUM_DEPRECATE_SOON }

Functions
void V8_EXPORT	RegisterExtension (std::unique_ptr< Extension >)

template<const CTypeInfo * type_info, typename T >
	V8_DEPRECATED ("Use TryToCopyAndConvertArrayToCppBuffer<CTypeInfo::Identifier, T>()") bool V8_EXPORT V8_WARN_UNUSED_RESULT TryCopyAndConvertArrayToCppBuffer(Local< Array > src

template<>
	V8_DEPRECATED ("Use TryToCopyAndConvertArrayToCppBuffer<CTypeInfo::Identifier, T>()") inline bool V8_WARN_UNUSED_RESULT TryCopyAndConvertArrayToCppBuffer< &kTypeInfoInt32

	int32_t (Local< Array > src, int32_t *dst, uint32_t max_length)

	double (Local< Array > src, double *dst, uint32_t max_length)

template<CTypeInfo::Identifier type_info_id, typename T >
bool V8_EXPORT V8_WARN_UNUSED_RESULT	TryToCopyAndConvertArrayToCppBuffer (Local< Array > src, T *dst, uint32_t max_length)

template<class T >
Maybe< T >	Nothing ()

template<class T >
Maybe< T >	Just (const T &t)

Maybe< void >	JustVoid ()

PlatformSharedMemoryHandle	SharedMemoryHandleFromFileDescriptor (int fd)

int	FileDescriptorFromSharedMemoryHandle (PlatformSharedMemoryHandle handle)

V8_INLINE Local< Primitive >	Undefined (Isolate *isolate)

V8_INLINE Local< Primitive >	Null (Isolate *isolate)

V8_INLINE Local< Boolean >	True (Isolate *isolate)

V8_INLINE Local< Boolean >	False (Isolate *isolate)

V8_INLINE bool	operator== (const TracedReferenceBase &lhs, const TracedReferenceBase &rhs)

template<typename U >
V8_INLINE bool	operator== (const TracedReferenceBase &lhs, const v8::Local< U > &rhs)

template<typename U >
V8_INLINE bool	operator== (const v8::Local< U > &lhs, const TracedReferenceBase &rhs)

V8_INLINE bool	operator!= (const TracedReferenceBase &lhs, const TracedReferenceBase &rhs)

template<typename U >
V8_INLINE bool	operator!= (const TracedReferenceBase &lhs, const v8::Local< U > &rhs)

template<typename U >
V8_INLINE bool	operator!= (const v8::Local< U > &lhs, const TracedReferenceBase &rhs)

constexpr uint32_t	CurrentValueSerializerFormatVersion ()

V8_EXPORT bool	TryHandleWebAssemblyTrapPosix (int sig_code, siginfo_t info, void context)

V8_EXPORT bool	TryHandleWebAssemblyTrapWindows (EXCEPTION_POINTERS *exception)

Variables
T *	dst

T uint32_t	max_length

Detailed Description

This file provides additional API on top of the default one for making API calls, which come from embedder C++ functions. The functions are being called directly from optimized code, doing all the necessary typechecks in the compiler itself, instead of on the embedder side. Hence the "fast" in the name. Example usage might look like:

void FastMethod(int param, bool another_param);
 
v8::FunctionTemplate::New(isolate, SlowCallback, data,
                          signature, length, constructor_behavior
                          side_effect_type,
                          &v8::CFunction::Make(FastMethod));

By design, fast calls are limited by the following requirements, which the embedder should enforce themselves:

they should not allocate on the JS heap;
they should not trigger JS execution. To enforce them, the embedder could use the existing v8::Isolate::DisallowJavascriptExecutionScope and a utility similar to Blink's NoAllocationScope: https://source.chromium.org/chromium/chromium/src/+/master:third_party/blink/renderer/platform/heap/thread_state_scopes.h;l=16

Due to these limitations, it's not directly possible to report errors by throwing a JS exception or to otherwise do an allocation. There is an alternative way of creating fast calls that supports falling back to the slow call and then performing the necessary allocation. When one creates the fast method by using CFunction::MakeWithFallbackSupport instead of CFunction::Make, the fast callback gets as last parameter an output variable, through which it can request falling back to the slow call. So one might declare their method like:

void FastMethodWithFallback(int param, FastApiCallbackOptions& options);

If the callback wants to signal an error condition or to perform an allocation, it must set options.fallback to true and do an early return from the fast method. Then V8 checks the value of options.fallback and if it's true, falls back to executing the SlowCallback, which is capable of reporting the error (either by throwing a JS exception or logging to the console) or doing the allocation. It's the embedder's responsibility to ensure that the fast callback is idempotent up to the point where error and fallback conditions are checked, because otherwise executing the slow callback might produce visible side-effects twice.

An example for custom embedder type support might employ a way to wrap/ unwrap various C++ types in JSObject instances, e.g:

// Helper method with a check for field count.
template <typename T, int offset>
inline T* GetInternalField(v8::Local<v8::Object> wrapper) {
  assert(offset < wrapper->InternalFieldCount());
  return reinterpret_cast<T*>(
      wrapper->GetAlignedPointerFromInternalField(offset));
}
 
class CustomEmbedderType {
 public:
  // Returns the raw C object from a wrapper JS object.
  static CustomEmbedderType* Unwrap(v8::Local<v8::Object> wrapper) {
    return GetInternalField<CustomEmbedderType,
                            kV8EmbedderWrapperObjectIndex>(wrapper);
  }
  static void FastMethod(v8::Local<v8::Object> receiver_obj, int param) {
    CustomEmbedderType* receiver = static_cast<CustomEmbedderType*>(
      receiver_obj->GetAlignedPointerFromInternalField(
        kV8EmbedderWrapperObjectIndex));
 
    // Type checks are already done by the optimized code.
    // Then call some performance-critical method like:
    // receiver->Method(param);
  }
 
  static void SlowMethod(
      const v8::FunctionCallbackInfo<v8::Value>& info) {
    v8::Local<v8::Object> instance =
      v8::Local<v8::Object>::Cast(info.Holder());
    CustomEmbedderType* receiver = Unwrap(instance);
    // TODO: Do type checks and extract {param}.
    receiver->Method(param);
  }
};
 
// TODO(mslekova): Clean-up these constants
// The constants kV8EmbedderWrapperTypeIndex and
// kV8EmbedderWrapperObjectIndex describe the offsets for the type info
// struct and the native object, when expressed as internal field indices
// within a JSObject. The existance of this helper function assumes that
// all embedder objects have their JSObject-side type info at the same
// offset, but this is not a limitation of the API itself. For a detailed
// use case, see the third example.
static constexpr int kV8EmbedderWrapperTypeIndex = 0;
static constexpr int kV8EmbedderWrapperObjectIndex = 1;
 
// The following setup function can be templatized based on
// the {embedder_object} argument.
void SetupCustomEmbedderObject(v8::Isolate* isolate,
                               v8::Local<v8::Context> context,
                               CustomEmbedderType* embedder_object) {
  isolate->set_embedder_wrapper_type_index(
    kV8EmbedderWrapperTypeIndex);
  isolate->set_embedder_wrapper_object_index(
    kV8EmbedderWrapperObjectIndex);
 
  v8::CFunction c_func =
    MakeV8CFunction(CustomEmbedderType::FastMethod);
 
  Local<v8::FunctionTemplate> method_template =
    v8::FunctionTemplate::New(
      isolate, CustomEmbedderType::SlowMethod, v8::Local<v8::Value>(),
      v8::Local<v8::Signature>(), 1, v8::ConstructorBehavior::kAllow,
      v8::SideEffectType::kHasSideEffect, &c_func);
 
  v8::Local<v8::ObjectTemplate> object_template =
    v8::ObjectTemplate::New(isolate);
  object_template->SetInternalFieldCount(
    kV8EmbedderWrapperObjectIndex + 1);
  object_template->Set(isolate, "method", method_template);
 
  // Instantiate the wrapper JS object.
  v8::Local<v8::Object> object =
      object_template->NewInstance(context).ToLocalChecked();
  object->SetAlignedPointerInInternalField(
    kV8EmbedderWrapperObjectIndex,
    reinterpret_cast<void*>(embedder_object));
 
  // TODO: Expose {object} where it's necessary.
}

For instance if {object} is exposed via a global "obj" variable, one could write in JS: function hot_func() { obj.method(42); } and once {hot_func} gets optimized, CustomEmbedderType::FastMethod will be called instead of the slow version, with the following arguments: receiver := the {embedder_object} from above param := 42

Currently supported return types:

void
bool
int32_t
uint32_t
float32_t
float64_t Currently supported argument types:

pointer to an embedder type

JavaScript array of primitive types
bool
int32_t
uint32_t
int64_t
uint64_t
float32_t
float64_t

The 64-bit integer types currently have the IDL (unsigned) long long semantics: https://heycam.github.io/webidl/#abstract-opdef-converttoint In the future we'll extend the API to also provide conversions from/to BigInt to preserve full precision. The floating point types currently have the IDL (unrestricted) semantics, which is the only one used by WebGL. We plan to add support also for restricted floats/doubles, similarly to the BigInt conversion policies. We also differ from the specific NaN bit pattern that WebIDL prescribes (https://heycam.github.io/webidl/#es-unrestricted-float) in that Blink passes NaN values as-is, i.e. doesn't normalize them.

To be supported types:

TypedArrays and ArrayBuffers
arrays of embedder types

The API offers a limited support for function overloads:

void FastMethod_2Args(int param, bool another_param);
void FastMethod_3Args(int param, bool another_param, int third_param);
 
v8::CFunction fast_method_2args_c_func =
     MakeV8CFunction(FastMethod_2Args);
v8::CFunction fast_method_3args_c_func =
     MakeV8CFunction(FastMethod_3Args);
const v8::CFunction fast_method_overloads[] = {fast_method_2args_c_func,
                                               fast_method_3args_c_func};
Local<v8::FunctionTemplate> method_template =
    v8::FunctionTemplate::NewWithCFunctionOverloads(
        isolate, SlowCallback, data, signature, length,
        constructor_behavior, side_effect_type,
        {fast_method_overloads, 2});

In this example a single FunctionTemplate is associated to multiple C++ functions. The overload resolution is currently only based on the number of arguments passed in a call. For example, if this method_template is registered with a wrapper JS object as described above, a call with two arguments: obj.method(42, true); will result in a fast call to FastMethod_2Args, while a call with three or more arguments: obj.method(42, true, 11); will result in a fast call to FastMethod_3Args. Instead a call with less than two arguments, like: obj.method(42); would not result in a fast call but would fall back to executing the associated SlowCallback.

The v8 JavaScript engine.

Profiler support for the V8 JavaScript engine.

Support for Persistent containers.

C++11 embedders can use STL containers with Global values, but pre-C++11 does not support the required move semantic and hence may want these container classes.

Compile-time constants.

This header provides access to information about the value serializer at compile time, without declaring or defining any symbols that require linking to V8.

Typedef Documentation

◆ AccessCheckCallback

using AccessCheckCallback = bool (*)(Local<Context> accessing_context, Local<Object> accessed_object, Local<Value> data)

Returns true if the given context should be allowed to access the given object.

Definition at line 354 of file v8-template.h.

◆ AccessorGetterCallback

using AccessorGetterCallback = void (*)(Local<String> property, const PropertyCallbackInfo<Value>& info)

Accessor[Getter|Setter] are used as callback functions when setting|getting a particular property. See Object and ObjectTemplate's method SetAccessor.

Definition at line 153 of file v8-object.h.

◆ AccessorNameGetterCallback

using AccessorNameGetterCallback = void (*)(Local<Name> property, const PropertyCallbackInfo<Value>& info)

Definition at line 155 of file v8-object.h.

◆ AccessorNameSetterCallback

using AccessorNameSetterCallback = void (*)(Local<Name> property, Local<Value> value, const PropertyCallbackInfo<void>& info)

Definition at line 161 of file v8-object.h.

◆ AccessorSetterCallback

using AccessorSetterCallback = void (*)(Local<String> property, Local<Value> value, const PropertyCallbackInfo<void>& info)

Definition at line 158 of file v8-object.h.

◆ AddCrashKeyCallback

using AddCrashKeyCallback = void (*)(CrashKeyId id, const std::string& value)

Definition at line 238 of file v8-callbacks.h.

◆ AddHistogramSampleCallback

using AddHistogramSampleCallback = void (*)(void* histogram, int sample)

Definition at line 213 of file v8-callbacks.h.

◆ AllowCodeGenerationFromStringsCallback

using AllowCodeGenerationFromStringsCallback = bool (*)(Local<Context> context, Local<String> source)

Callback to check if code generation from strings is allowed. See Context::AllowCodeGenerationFromStrings.

Definition at line 250 of file v8-callbacks.h.

◆ AllowWasmCodeGenerationCallback

using AllowWasmCodeGenerationCallback = bool (*)(Local<Context> context, Local<String> source)

Definition at line 293 of file v8-callbacks.h.

◆ ApiImplementationCallback

using ApiImplementationCallback = void (*)(const FunctionCallbackInfo<Value>&)

Definition at line 298 of file v8-callbacks.h.

◆ BackingStoreDeleterCallback

using BackingStoreDeleterCallback = void (*)(void* data, size_t length, void* deleter_data)

Definition at line 107 of file v8-array-buffer.h.

◆ BeforeCallEnteredCallback

using BeforeCallEnteredCallback = void (*)(Isolate*)

Definition at line 241 of file v8-callbacks.h.

◆ CallCompletedCallback

using CallCompletedCallback = void (*)(Isolate*)

Definition at line 242 of file v8-callbacks.h.

◆ CFunctionBuilder

using CFunctionBuilder = internal::CFunctionBuilder

Definition at line 866 of file v8-fast-api-calls.h.

◆ CounterLookupCallback

using CounterLookupCallback = int* (*)(const char* name)

Callback function passed to SetUnhandledExceptionCallback.

Definition at line 208 of file v8-callbacks.h.

◆ CreateHistogramCallback

using CreateHistogramCallback = void* (*)(const char* name, int min, int max, size_t buckets)

Definition at line 210 of file v8-callbacks.h.

◆ DcheckErrorCallback

using DcheckErrorCallback = void (*)(const char* file, int line, const char* message)

Definition at line 51 of file v8-initialization.h.

◆ DeserializeEmbedderFieldsCallback

using DeserializeEmbedderFieldsCallback = DeserializeInternalFieldsCallback

Definition at line 70 of file v8-snapshot.h.

◆ EntropySource

using EntropySource = bool (*)(unsigned char* buffer, size_t length)

EntropySource is used as a callback function when v8 needs a source of entropy.

Definition at line 33 of file v8-initialization.h.

◆ ExtensionCallback

using ExtensionCallback = bool (*)(const FunctionCallbackInfo<Value>&)

Definition at line 291 of file v8-callbacks.h.

◆ FailedAccessCheckCallback

using FailedAccessCheckCallback = void (*)(Local<Object> target, AccessType type, Local<Value> data)

Definition at line 275 of file v8-callbacks.h.

◆ FatalErrorCallback

using FatalErrorCallback = void (*)(const char* location, const char* message)

Definition at line 217 of file v8-callbacks.h.

◆ FunctionCallback

using FunctionCallback = void (*)(const FunctionCallbackInfo<Value>& info)

Definition at line 251 of file v8-function-callback.h.

◆ GCCallback

using GCCallback = void (*)(GCType type, GCCallbackFlags flags)

Definition at line 184 of file v8-callbacks.h.

◆ GenericNamedPropertyDefinerCallback

using GenericNamedPropertyDefinerCallback = void (*)(Local<Name> property, const PropertyDescriptor& desc, const PropertyCallbackInfo<Value>& info)

Interceptor for defineProperty requests on an object.

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().

Parameters

property	The name of the property for which the request was intercepted.
desc	The property descriptor which is used to define the property if the request is not intercepted.
info	Information about the intercepted request, such as isolate, receiver, return value, or whether running in ‘'use strict’`mode. See`PropertyCallbackInfo`.

◆ GenericNamedPropertyDeleterCallback

using GenericNamedPropertyDeleterCallback = void (*)(Local<Name> property, const PropertyCallbackInfo<Boolean>& info)

Interceptor for delete requests on an object.

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.

Parameters

property	The name of the property for which the request was intercepted.
info	Information about the intercepted request, such as isolate, receiver, return value, or whether running in ‘'use strict’`mode. See`PropertyCallbackInfo`.

Note: If you need to mimic the behavior of delete, i.e., throw in strict mode instead of returning false, use info.ShouldThrowOnError() to determine if you are in strict mode.

◆ GenericNamedPropertyDescriptorCallback

using GenericNamedPropertyDescriptorCallback = void (*)(Local<Name> property, const PropertyCallbackInfo<Value>& info)

Interceptor for getOwnPropertyDescriptor requests on an object.

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.

Parameters

property The name of the property for which the request was intercepted. \info Information about the intercepted request, such as isolate, receiver, return value, or whether running in ‘'use strict’mode. SeePropertyCallbackInfo`.

Note: If GetOwnPropertyDescriptor is intercepted, it will always return true, i.e., indicate that the property was found.

◆ GenericNamedPropertyEnumeratorCallback

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

Returns an array containing the names of the properties the named property getter intercepts.

Note: The values in the array must be of type v8::Name.

Definition at line 254 of file v8-template.h.

◆ GenericNamedPropertyGetterCallback

using GenericNamedPropertyGetterCallback = void (*)(Local<Name> property, const PropertyCallbackInfo<Value>& info)

Interceptor for get requests on an object.

Use info.GetReturnValue().Set() to set the return value of the intercepted get request.

Parameters

property	The name of the property for which the request was intercepted.
info	Information about the intercepted request, such as isolate, receiver, return value, or whether running in `'use strict`' mode. See `PropertyCallbackInfo`.

void GetterCallback(
  Local<Name> name,
  const v8::PropertyCallbackInfo<v8::Value>& info) {
    info.GetReturnValue().Set(v8_num(42));
}
 
v8::Local<v8::FunctionTemplate> templ =
    v8::FunctionTemplate::New(isolate);
templ->InstanceTemplate()->SetHandler(
    v8::NamedPropertyHandlerConfiguration(GetterCallback));
LocalContext env;
env->Global()
    ->Set(env.local(), v8_str("obj"), templ->GetFunction(env.local())
                                           .ToLocalChecked()
                                           ->NewInstance(env.local())
                                           .ToLocalChecked())
    .FromJust();
v8::Local<v8::Value> result = CompileRun("obj.a = 17; obj.a");
CHECK(v8_num(42)->Equals(env.local(), result).FromJust());

◆ GenericNamedPropertyQueryCallback

using GenericNamedPropertyQueryCallback = void (*)(Local<Name> property, const PropertyCallbackInfo<Integer>& info)

Intercepts all requests that query the attributes of the property, e.g., getOwnPropertyDescriptor(), propertyIsEnumerable(), and defineProperty().

Use info.GetReturnValue().Set(value) to set the property attributes. The value is an integer encoding a v8::PropertyAttribute.

Parameters

property	The name of the property for which the request was intercepted.
info	Information about the intercepted request, such as isolate, receiver, return value, or whether running in ‘'use strict’`mode. See`PropertyCallbackInfo`.

Note: Some functions query the property attributes internally, even though they do not return the attributes. For example, hasOwnProperty() can trigger this interceptor depending on the state of the object.

◆ GenericNamedPropertySetterCallback

using GenericNamedPropertySetterCallback = void (*)(Local<Name> property, Local<Value> value, const PropertyCallbackInfo<Value>& info)

Interceptor for set requests on an object.

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().

Parameters

property	The name of the property for which the request was intercepted.
value	The value which the property will have if the request is not intercepted.
info	Information about the intercepted request, such as isolate, receiver, return value, or whether running in ‘'use strict’`mode. See`PropertyCallbackInfo`.

◆ Handle

using Handle = Local<T>

Definition at line 335 of file v8-local-handle.h.

◆ HostCreateShadowRealmContextCallback

using HostCreateShadowRealmContextCallback = MaybeLocal<Context> (*)(Local<Context> initiator_context)

HostCreateShadowRealmContextCallback is called each time a ShadowRealm is being constructed in the initiator_context.

The method combines Context creation and implementation defined abstract operation HostInitializeShadowRealm into one.

The embedder should use v8::Context::New or v8::Context:NewFromSnapshot to create a new context. If the creation fails, the embedder must propagate that exception by returning an empty MaybeLocal.

Definition at line 381 of file v8-callbacks.h.

◆ HostImportModuleDynamicallyCallback

using HostImportModuleDynamicallyCallback = MaybeLocal<Promise> (*)( Local<Context> context, Local<Data> host_defined_options, Local<Value> resource_name, Local<String> specifier, Local<FixedArray> import_assertions)

Definition at line 351 of file v8-callbacks.h.

◆ HostImportModuleDynamicallyWithImportAssertionsCallback

using HostImportModuleDynamicallyWithImportAssertionsCallback = MaybeLocal<Promise> (*)(Local<Context> context, Local<ScriptOrModule> referrer, Local<String> specifier, Local<FixedArray> import_assertions)

HostImportModuleDynamicallyCallback is called when we require the embedder to load a module. This is used as part of the dynamic import syntax.

The referrer contains metadata about the script/module that calls import.

The specifier is the name of the module that should be imported.

The import_assertions are import assertions for this request in the form: [key1, value1, key2, value2, ...] where the keys and values are of type v8::String. Note, unlike the FixedArray passed to ResolveModuleCallback and returned from ModuleRequest::GetImportAssertions(), this array does not contain the source Locations of the assertions.

The embedder must compile, instantiate, evaluate the Module, and obtain its namespace object.

The Promise returned from this function is forwarded to userland JavaScript. The embedder must resolve this promise with the module namespace object. In case of an exception, the embedder must reject this promise with the exception. If the promise creation itself fails (e.g. due to stack overflow), the embedder must propagate that exception by returning an empty MaybeLocal.

Definition at line 346 of file v8-callbacks.h.

◆ HostInitializeImportMetaObjectCallback

using HostInitializeImportMetaObjectCallback = void (*)(Local<Context> context, Local<Module> module, Local<Object> meta)

HostInitializeImportMetaObjectCallback is called the first time import.meta is accessed for a module. Subsequent access will reuse the same value.

The method combines two implementation-defined abstract operations into one: HostGetImportMetaProperties and HostFinalizeImportMeta.

The embedder should use v8::Object::CreateDataProperty to add properties on the meta object.

Definition at line 366 of file v8-callbacks.h.

◆ IndexedPropertyDefinerCallback

using IndexedPropertyDefinerCallback = void (*)(uint32_t index, const PropertyDescriptor& desc, const PropertyCallbackInfo<Value>& info)

See v8::GenericNamedPropertyDefinerCallback.

Definition at line 340 of file v8-template.h.

◆ IndexedPropertyDeleterCallback

using IndexedPropertyDeleterCallback = void (*)(uint32_t index, const PropertyCallbackInfo<Boolean>& info)

See v8::GenericNamedPropertyDeleterCallback.

Definition at line 325 of file v8-template.h.

◆ IndexedPropertyDescriptorCallback

using IndexedPropertyDescriptorCallback = void (*)(uint32_t index, const PropertyCallbackInfo<Value>& info)

See v8::GenericNamedPropertyDescriptorCallback.

Definition at line 347 of file v8-template.h.

◆ IndexedPropertyEnumeratorCallback

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

Returns an array containing the indices of the properties the indexed property getter intercepts.

Note: The values in the array must be uint32_t.

Definition at line 334 of file v8-template.h.

◆ IndexedPropertyGetterCallback

using IndexedPropertyGetterCallback = void (*)(uint32_t index, const PropertyCallbackInfo<Value>& info)

See v8::GenericNamedPropertyGetterCallback.

Definition at line 306 of file v8-template.h.

◆ IndexedPropertyQueryCallback

using IndexedPropertyQueryCallback = void (*)(uint32_t index, const PropertyCallbackInfo<Integer>& info)

See v8::GenericNamedPropertyQueryCallback.

Definition at line 319 of file v8-template.h.

◆ IndexedPropertySetterCallback

using IndexedPropertySetterCallback = void (*)(uint32_t index, Local<Value> value, const PropertyCallbackInfo<Value>& info)

See v8::GenericNamedPropertySetterCallback.

Definition at line 312 of file v8-template.h.

◆ InterruptCallback

using InterruptCallback = void (*)(Isolate* isolate, void* data)

Definition at line 186 of file v8-callbacks.h.

◆ JitCodeEventHandler

using JitCodeEventHandler = void (*)(const JitCodeEvent* event)

Callback function passed to SetJitCodeEventHandler.

Parameters

event code add, move or removal event.

Definition at line 138 of file v8-callbacks.h.

◆ LogEventCallback

using LogEventCallback = void (*)(const char* name, int status)

Definition at line 226 of file v8-callbacks.h.

◆ MessageCallback

using MessageCallback = void (*)(Local<Message> message, Local<Value> data)

Definition at line 221 of file v8-callbacks.h.

◆ MicrotaskCallback

using MicrotaskCallback = void (*)(void* data)

Definition at line 14 of file v8-microtask.h.

◆ MicrotasksCompletedCallbackWithData

using MicrotasksCompletedCallbackWithData = void (*)(Isolate*, void*)

Definition at line 13 of file v8-microtask.h.

◆ ModifyCodeGenerationFromStringsCallback

using ModifyCodeGenerationFromStringsCallback = ModifyCodeGenerationFromStringsResult (*)(Local<Context> context, Local<Value> source)

Callback to check if codegen is allowed from a source object, and convert the source to string if necessary. See: ModifyCodeGenerationFromStrings.

Definition at line 282 of file v8-callbacks.h.

◆ ModifyCodeGenerationFromStringsCallback2

using ModifyCodeGenerationFromStringsCallback2 = ModifyCodeGenerationFromStringsResult (*)(Local<Context> context, Local<Value> source, bool is_code_like)

Definition at line 285 of file v8-callbacks.h.

◆ NativeObject

using NativeObject = int void*

Definition at line 29 of file v8-profiler.h.

◆ NearHeapLimitCallback

using NearHeapLimitCallback = size_t (*)(void* data, size_t current_heap_limit, size_t initial_heap_limit)

This callback is invoked when the heap size is close to the heap limit and V8 is likely to abort with out-of-memory error. The callback can extend the heap limit by returning a value that is greater than the current_heap_limit. The initial heap limit is the limit that was set after heap setup.

Definition at line 195 of file v8-callbacks.h.

◆ OOMErrorCallback

using OOMErrorCallback = void (*)(const char* location, bool is_heap_oom)

Definition at line 219 of file v8-callbacks.h.

◆ PersistentContainerValue

typedef uintptr_t PersistentContainerValue

Definition at line 28 of file v8-util.h.

◆ PlatformSharedMemoryHandle

using PlatformSharedMemoryHandle = intptr_t

Definition at line 516 of file v8-platform.h.

◆ PrepareStackTraceCallback

using PrepareStackTraceCallback = MaybeLocal<Value> (*)(Local<Context> context, Local<Value> error, Local<Array> sites)

PrepareStackTraceCallback is called when the stack property of an error is first accessed. The return value will be used as the stack value. If this callback is registed, the |Error.prepareStackTrace| API will be disabled. |sites| is an array of call sites, specified in https://v8.dev/docs/stack-trace-api

Definition at line 391 of file v8-callbacks.h.

◆ PromiseHook

using PromiseHook = void (*)(PromiseHookType type, Local<Promise> promise, Local<Value> parent)

Definition at line 143 of file v8-promise.h.

◆ PromiseRejectCallback

using PromiseRejectCallback = void (*)(PromiseRejectMessage message)

Definition at line 170 of file v8-promise.h.

◆ ReturnAddressLocationResolver

using ReturnAddressLocationResolver = uintptr_t (*)(uintptr_t return_addr_location)

ReturnAddressLocationResolver is used as a callback function when v8 is resolving the location of a return address on the stack. Profilers that change the return address on the stack can use this to resolve the stack location to wherever the profiler stashed the original return address.

Parameters

return_addr_location A location on stack where a machine return address resides.

Returns: Either return_addr_location, or else a pointer to the profiler's copy of the original return address.

Note: The resolver function must not cause garbage collection.

Definition at line 48 of file v8-initialization.h.

◆ SerializeEmbedderFieldsCallback

using SerializeEmbedderFieldsCallback = SerializeInternalFieldsCallback

Definition at line 53 of file v8-snapshot.h.

◆ SharedArrayBufferConstructorEnabledCallback

using SharedArrayBufferConstructorEnabledCallback = bool (*)(Local<Context> context)

Definition at line 317 of file v8-callbacks.h.

◆ SnapshotObjectId

using SnapshotObjectId = uint32_t

Definition at line 30 of file v8-profiler.h.

◆ UniquePersistent

using UniquePersistent = Global<T>

Definition at line 435 of file v8-persistent-handle.h.

◆ WasmDynamicTieringEnabledCallback

using WasmDynamicTieringEnabledCallback = bool (*)(Local<Context> context)

Definition at line 314 of file v8-callbacks.h.

◆ WasmExceptionsEnabledCallback

using WasmExceptionsEnabledCallback = bool (*)(Local<Context> context)

Definition at line 311 of file v8-callbacks.h.

◆ WasmLoadSourceMapCallback

using WasmLoadSourceMapCallback = Local<String> (*)(Isolate* isolate, const char* name)

Definition at line 304 of file v8-callbacks.h.

◆ WasmSimdEnabledCallback

using WasmSimdEnabledCallback = bool (*)(Local<Context> context)

Definition at line 308 of file v8-callbacks.h.

◆ WasmStreamingCallback

using WasmStreamingCallback = void (*)(const FunctionCallbackInfo<Value>&)

Definition at line 301 of file v8-callbacks.h.

Enumeration Type Documentation

◆ AccessControl

enum AccessControl

Access control specifications.

Some accessors should be accessible across contexts. These accessors have an explicit access control parameter which specifies the kind of cross-context access that should be allowed.

TODO(dcarney): Remove PROHIBITS_OVERWRITING as it is now unused.

Enumerator
DEFAULT
ALL_CAN_READ
ALL_CAN_WRITE
PROHIBITS_OVERWRITING

Definition at line 174 of file v8-object.h.

◆ AccessType

enum AccessType

Access type specification.

Enumerator
ACCESS_GET
ACCESS_SET
ACCESS_HAS
ACCESS_DELETE
ACCESS_KEYS

Definition at line 265 of file v8-callbacks.h.

◆ ArrayBufferCreationMode

enum ArrayBufferCreationMode

strong

Enumerator
kInternalized
kExternalized

Definition at line 25 of file v8-array-buffer.h.

◆ CodeEventType

enum CodeEventType

Note that this enum may be extended in the future. Please include a default case if this enum is used in a switch statement.

Enumerator
kUnknownType

Definition at line 1058 of file v8-profiler.h.

◆ ConstructorBehavior

enum ConstructorBehavior

strong

Enumerator
kThrow
kAllow

Definition at line 358 of file v8-template.h.

◆ CpuProfilingLoggingMode

enum CpuProfilingLoggingMode

Enumerator
kLazyLogging
kEagerLogging

Definition at line 258 of file v8-profiler.h.

◆ CpuProfilingMode

enum CpuProfilingMode

Enumerator
kLeafNodeLineNumbers
kCallerLineNumbers

Definition at line 239 of file v8-profiler.h.

◆ CpuProfilingNamingMode

enum CpuProfilingNamingMode

Enumerator
kStandardNaming
kDebugNaming

Definition at line 250 of file v8-profiler.h.

◆ CpuProfilingStatus

enum CpuProfilingStatus

strong

Enumerator
kStarted
kAlreadyStarted
kErrorTooManyProfilers

Definition at line 270 of file v8-profiler.h.

◆ CrashKeyId

enum CrashKeyId

strong

Enumerator
kIsolateAddress
kReadonlySpaceFirstPageAddress
kMapSpaceFirstPageAddress
kCodeSpaceFirstPageAddress
kDumpType

Definition at line 230 of file v8-callbacks.h.

◆ EmbedderStateTag

enum EmbedderStateTag : uint8_t

strong

Enumerator
EMPTY
OTHER

Definition at line 21 of file v8-embedder-state-scope.h.

◆ GCCallbackFlags

enum GCCallbackFlags

GCCallbackFlags is used to notify additional information about the GC callback.

kGCCallbackFlagConstructRetainedObjectInfos: The GC callback is for constructing retained object infos.
kGCCallbackFlagForced: The GC callback is for a forced GC for testing.
kGCCallbackFlagSynchronousPhantomCallbackProcessing: The GC callback is called synchronously without getting posted to an idle task.
kGCCallbackFlagCollectAllAvailableGarbage: The GC callback is called in a phase where V8 is trying to collect all available garbage (e.g., handling a low memory notification).
kGCCallbackScheduleIdleGarbageCollection: The GC callback is called to trigger an idle garbage collection.

Enumerator
kNoGCCallbackFlags
kGCCallbackFlagConstructRetainedObjectInfos
kGCCallbackFlagForced
kGCCallbackFlagSynchronousPhantomCallbackProcessing
kGCCallbackFlagCollectAllAvailableGarbage
kGCCallbackFlagCollectAllExternalMemory
kGCCallbackScheduleIdleGarbageCollection

Definition at line 174 of file v8-callbacks.h.

◆ GCType

enum GCType

Applications can register callback functions which will be called before and after certain garbage collection operations. Allocations are not allowed in the callback functions, you therefore cannot manipulate objects (set or delete properties for example) since it is possible such operations will result in the allocation of objects.

Enumerator
kGCTypeScavenge
kGCTypeMinorMarkCompact
kGCTypeMarkSweepCompact
kGCTypeIncrementalMarking
kGCTypeProcessWeakCallbacks
kGCTypeAll

Definition at line 149 of file v8-callbacks.h.

◆ IndexFilter

enum IndexFilter

strong

kIncludesIndices allows for integer indices to be collected, while kSkipIndices will exclude integer indices from being collected.

Enumerator
kIncludeIndices
kSkipIndices

Definition at line 222 of file v8-object.h.

◆ IntegrityLevel

enum IntegrityLevel

strong

Integrity level for objects.

Enumerator
kFrozen
kSealed

Definition at line 233 of file v8-object.h.

◆ Intrinsic

enum Intrinsic

Definition at line 36 of file v8-template.h.

◆ JitCodeEventOptions

enum JitCodeEventOptions

Option flags passed to the SetJitCodeEventHandler function.

Enumerator
kJitCodeEventDefault
kJitCodeEventEnumExisting

Definition at line 127 of file v8-callbacks.h.

◆ KeyCollectionMode

enum KeyCollectionMode

strong

Keys/Properties filter enums:

KeyCollectionMode limits the range of collected properties. kOwnOnly limits the collected properties to the given Object only. kIncludesPrototypes will include all keys of the objects's prototype chain as well.

Enumerator
kOwnOnly
kIncludePrototypes

Definition at line 216 of file v8-object.h.

◆ KeyConversionMode

enum KeyConversionMode

strong

kConvertToString will convert integer indices to strings. kKeepNumbers will return numbers for integer indices.

Enumerator
kConvertToString
kKeepNumbers
kNoNumbers

Definition at line 228 of file v8-object.h.

◆ LogEventStatus

enum LogEventStatus : int

Enumerator
kStart
kEnd
kStamp

Definition at line 225 of file v8-callbacks.h.

◆ MeasureMemoryExecution

enum MeasureMemoryExecution

strong

Controls how promptly a memory measurement request is executed. By default the measurement is folded with the next scheduled GC which may happen after a while and is forced after some timeout. The kEager mode starts incremental GC right away and is useful for testing. The kLazy mode does not force GC.

Enumerator
kDefault
kEager
kLazy

Definition at line 42 of file v8-statistics.h.

◆ MeasureMemoryMode

enum MeasureMemoryMode

strong

Controls how the default MeasureMemoryDelegate reports the result of the memory measurement to JS. With kSummary only the total size is reported. With kDetailed the result includes the size of each native context.

Enumerator
kSummary
kDetailed

Definition at line 33 of file v8-statistics.h.

◆ MemoryPressureLevel

enum MemoryPressureLevel

strong

Memory pressure level for the MemoryPressureNotification. kNone hints V8 that there is no memory pressure. kModerate hints V8 to speed up incremental garbage collection at the cost of of higher latency due to garbage collection pauses. kCritical hints V8 to free memory as soon as possible. Garbage collection pauses at this level will be large.

Enumerator
kNone
kModerate
kCritical

Definition at line 195 of file v8-isolate.h.

◆ MicrotasksPolicy

enum MicrotasksPolicy

strong

Policy for running microtasks:

explicit: microtasks are invoked with the Isolate::PerformMicrotaskCheckpoint() method;
scoped: microtasks invocation is controlled by MicrotasksScope objects;
auto: microtasks are invoked when the script call depth decrements to zero.

Enumerator
kExplicit
kScoped
kAuto

Definition at line 24 of file v8-microtask.h.

◆ NewStringType

enum NewStringType

strong

A flag describing different modes of string creation.

Aside from performance implications there are no differences between the two creation modes.

Enumerator
kNormal	Create a new string, always allocating new storage memory.
kInternalized	Acts as a hint that the string should be created in the old generation heap space and be deduplicated if an identical string already exists.

Definition at line 106 of file v8-primitive.h.

◆ PagePermissions

enum PagePermissions

strong

Possible permissions for memory pages.

Enumerator
kNoAccess
kRead
kReadWrite
kReadWriteExecute
kReadExecute

Definition at line 569 of file v8-platform.h.

◆ PersistentContainerCallbackType

enum PersistentContainerCallbackType

Enumerator
kNotWeak
kWeakWithParameter
kWeakWithInternalFields

Definition at line 30 of file v8-util.h.

◆ PromiseHookType

enum PromiseHookType

strong

PromiseHook with type kInit is called when a new promise is created. When a new promise is created as part of the chain in the case of Promise.then or in the intermediate promises created by Promise.{race, all}/AsyncFunctionAwait, we pass the parent promise otherwise we pass undefined.

PromiseHook with type kResolve is called at the beginning of resolve or reject function defined by CreateResolvingFunctions.

PromiseHook with type kBefore is called at the beginning of the PromiseReactionJob.

PromiseHook with type kAfter is called right at the end of the PromiseReactionJob.

Enumerator
kInit
kResolve
kBefore
kAfter

Definition at line 141 of file v8-promise.h.

◆ PromiseRejectEvent

enum PromiseRejectEvent

Enumerator
kPromiseRejectWithNoHandler
kPromiseHandlerAddedAfterReject
kPromiseRejectAfterResolved
kPromiseResolveAfterResolved

Definition at line 147 of file v8-promise.h.

◆ PropertyAttribute

enum PropertyAttribute

PropertyAttribute.

Enumerator
None	None.
ReadOnly	ReadOnly, i.e., not writable.
DontEnum	DontEnum, i.e., not enumerable.
DontDelete	DontDelete, i.e., not configurable.

Definition at line 137 of file v8-object.h.

◆ PropertyFilter

enum PropertyFilter

Property filter bits. They can be or'ed to build a composite filter.

Enumerator
ALL_PROPERTIES
ONLY_WRITABLE
ONLY_ENUMERABLE
ONLY_CONFIGURABLE
SKIP_STRINGS
SKIP_SYMBOLS

Definition at line 184 of file v8-object.h.

◆ PropertyHandlerFlags

enum PropertyHandlerFlags

strong

Configuration flags for v8::NamedPropertyHandlerConfiguration or v8::IndexedPropertyHandlerConfiguration.

Enumerator
kNone	None.
kAllCanRead	See ALL_CAN_READ above.
kNonMasking	Will not call into interceptor for properties on the receiver or prototype chain, i.e., only call into interceptor for properties that do not exist. Currently only valid for named interceptors.
kOnlyInterceptStrings	Will not call into interceptor for symbol lookup. Only meaningful for named interceptors.
kHasNoSideEffect	The getter, query, enumerator callbacks do not produce side effects.

Definition at line 603 of file v8-template.h.

◆ RAILMode

enum RAILMode : unsigned

Option flags passed to the SetRAILMode function. See documentation https://developers.google.com/web/tools/chrome-devtools/ profile/evaluate-performance/rail

Enumerator
PERFORMANCE_RESPONSE
PERFORMANCE_ANIMATION
PERFORMANCE_IDLE
PERFORMANCE_LOAD

Definition at line 170 of file v8-isolate.h.

◆ ScriptType

enum ScriptType

strong

Enumerator
kClassic
kModule

Definition at line 329 of file v8-script.h.

◆ SideEffectType

enum SideEffectType

strong

Options for marking whether callbacks may trigger JS-observable side effects. Side-effect-free callbacks are allowlisted during debug evaluation with throwOnSideEffect. It applies when calling a Function, FunctionTemplate, or an Accessor callback. For Interceptors, please see PropertyHandlerFlags's kHasNoSideEffect. Callbacks that only cause side effects to the receiver are allowlisted if invoked on receiver objects that are created within the same debug-evaluate call, as these objects are temporary and the side effect does not escape.

Enumerator
kHasSideEffect
kHasNoSideEffect
kHasSideEffectToReceiver

Definition at line 203 of file v8-object.h.

◆ StateTag

enum StateTag : int

Enumerator
JS
GC
PARSER
BYTECODE_COMPILER
COMPILER
OTHER
OTHER
EXTERNAL
ATOMICS_WAIT
IDLE

Definition at line 36 of file v8-unwinder.h.

◆ TaskPriority

enum TaskPriority : uint8_t

strong

Enumerator
kBestEffort	Best effort tasks are not critical for performance of the application. The platform implementation should preempt such tasks if higher priority tasks arrive.
kUserVisible	User visible tasks are long running background tasks that will improve performance and memory usage of the application upon completion. Example: background compilation and garbage collection.
kUserBlocking	User blocking tasks are highest priority tasks that block the execution thread (e.g. major garbage collection). They must be finished as soon as possible.

Definition at line 21 of file v8-platform.h.

◆ WeakCallbackType

enum WeakCallbackType

strong

Weakness type for weak handles.

Enumerator
kParameter	Passes a user-defined void* parameter back to the callback.
kInternalFields	Passes the first two internal fields of the object back to the callback.
V8_ENUM_DEPRECATE_SOON	Passes a user-defined void* parameter back to the callback. Will do so before the object is actually reclaimed, allowing it to be resurrected. In this case it is not possible to set a second-pass callback.

Definition at line 57 of file v8-weak-callback-info.h.

Function Documentation

◆ CurrentValueSerializerFormatVersion()

constexpr uint32_t v8::CurrentValueSerializerFormatVersion ( )

constexpr

Definition at line 20 of file v8-value-serializer-version.h.

◆ double()

v8::double	(	Local< Array >	src,
		double *	dst,
		uint32_t	max_length
	)

Definition at line 904 of file v8-fast-api-calls.h.

◆ False()

V8_INLINE Local<Boolean> v8::False ( Isolate * isolate )

Definition at line 852 of file v8-primitive.h.

◆ FileDescriptorFromSharedMemoryHandle()

int v8::FileDescriptorFromSharedMemoryHandle ( PlatformSharedMemoryHandle handle )

inline

Definition at line 560 of file v8-platform.h.

◆ int32_t()

v8::int32_t	(	Local< Array >	src,
		int32_t *	dst,
		uint32_t	max_length
	)

Definition at line 895 of file v8-fast-api-calls.h.

◆ Just()

Maybe<T> v8::Just ( const T & t )

inline

Definition at line 101 of file v8-maybe.h.

◆ JustVoid()

Maybe<void> v8::JustVoid ( )

inline

Definition at line 133 of file v8-maybe.h.

◆ Nothing()

Maybe<T> v8::Nothing ( )

inline

Definition at line 96 of file v8-maybe.h.

◆ Null()

V8_INLINE Local<Primitive> v8::Null ( Isolate * isolate )

Definition at line 836 of file v8-primitive.h.

◆ operator!=() [1/3]

V8_INLINE bool v8::operator!=	(	const TracedReferenceBase &	lhs,
		const TracedReferenceBase &	rhs
	)

Definition at line 491 of file v8-traced-handle.h.

References TracedReferenceBase::operator==.

◆ operator!=() [2/3]

V8_INLINE bool v8::operator!=	(	const TracedReferenceBase &	lhs,
		const v8::Local< U > &	rhs
	)

Definition at line 497 of file v8-traced-handle.h.

◆ operator!=() [3/3]

V8_INLINE bool v8::operator!=	(	const v8::Local< U > &	lhs,
		const TracedReferenceBase &	rhs
	)

Definition at line 503 of file v8-traced-handle.h.

◆ operator==() [1/3]

V8_INLINE bool v8::operator==	(	const TracedReferenceBase &	lhs,
		const TracedReferenceBase &	rhs
	)

Definition at line 466 of file v8-traced-handle.h.

◆ operator==() [2/3]

V8_INLINE bool v8::operator==	(	const TracedReferenceBase &	lhs,
		const v8::Local< U > &	rhs
	)

Definition at line 476 of file v8-traced-handle.h.

◆ operator==() [3/3]

V8_INLINE bool v8::operator==	(	const v8::Local< U > &	lhs,
		const TracedReferenceBase &	rhs
	)

Definition at line 486 of file v8-traced-handle.h.

◆ RegisterExtension()

void V8_EXPORT v8::RegisterExtension ( std::unique_ptr< Extension > )

◆ SharedMemoryHandleFromFileDescriptor()

PlatformSharedMemoryHandle v8::SharedMemoryHandleFromFileDescriptor ( int fd )

inline

Definition at line 557 of file v8-platform.h.

◆ True()

V8_INLINE Local<Boolean> v8::True ( Isolate * isolate )

Definition at line 844 of file v8-primitive.h.

◆ TryHandleWebAssemblyTrapPosix()

V8_EXPORT bool v8::TryHandleWebAssemblyTrapPosix	(	int	sig_code,
		siginfo_t *	info,
		void *	context
	)

This function determines whether a memory access violation has been an out-of-bounds memory access in WebAssembly. If so, it will modify the context parameter and add a return address where the execution can continue after the signal handling, and return true. Otherwise, false will be returned.

The parameters to this function correspond to those passed to a Posix signal handler. Use this function only on Linux and Mac.

Parameters

sig_code	The signal code, e.g. SIGSEGV.
info	A pointer to the siginfo_t struct provided to the signal handler.
context	A pointer to a ucontext_t struct provided to the signal handler.

◆ TryHandleWebAssemblyTrapWindows()

V8_EXPORT bool v8::TryHandleWebAssemblyTrapWindows ( EXCEPTION_POINTERS * exception )

This function determines whether a memory access violation has been an out-of-bounds memory access in WebAssembly. If so, it will modify the exception parameter and add a return address where the execution can continue after the exception handling, and return true. Otherwise the return value will be false.

The parameter to this function corresponds to the one passed to a Windows vectored exception handler. Use this function only on Windows.

Parameters

exception An EXCEPTION_POINTERS* as provided to the exception handler.

◆ TryToCopyAndConvertArrayToCppBuffer()

bool V8_EXPORT V8_WARN_UNUSED_RESULT v8::TryToCopyAndConvertArrayToCppBuffer	(	Local< Array >	src,
		T *	dst,
		uint32_t	max_length
	)

◆ Undefined()

V8_INLINE Local<Primitive> v8::Undefined ( Isolate * isolate )

Definition at line 828 of file v8-primitive.h.

◆ V8_DEPRECATED() [1/2]

v8::V8_DEPRECATED ( "Use TryToCopyAndConvertArrayToCppBuffer<CTypeInfo::Identifier, T>()" )

Copies the contents of this JavaScript array to a C++ buffer with a given max_length. A CTypeInfo is passed as an argument, instructing different rules for conversion (e.g. restricted float/double). The element type T of the destination array must match the C type corresponding to the CTypeInfo (specified by CTypeInfoTraits). If the array length is larger than max_length or the array is of unsupported type, the operation will fail, returning false. Generally, an array which contains objects, undefined, null or anything not convertible to the requested destination type, is considered unsupported. The operation returns true on success. type_info will be used for conversions.

◆ V8_DEPRECATED() [2/2]

V8_DEPRECATED ( "Use TryToCopyAndConvertArrayToCppBuffer<CTypeInfo::Identifier, T>()" ) &

Variable Documentation

◆ dst

T* dst

Definition at line 888 of file v8-fast-api-calls.h.

◆ max_length

T uint32_t max_length

Definition at line 889 of file v8-fast-api-calls.h.

Namespaces

Data Structures

Typedefs

Enumerations

Functions

Variables

Detailed Description

Typedef Documentation

◆ AccessCheckCallback

◆ AccessorGetterCallback

◆ AccessorNameGetterCallback

◆ AccessorNameSetterCallback

◆ AccessorSetterCallback

◆ AddCrashKeyCallback

◆ AddHistogramSampleCallback

◆ AllowCodeGenerationFromStringsCallback

◆ AllowWasmCodeGenerationCallback

◆ ApiImplementationCallback

◆ BackingStoreDeleterCallback

◆ BeforeCallEnteredCallback

◆ CallCompletedCallback

◆ CFunctionBuilder

◆ CounterLookupCallback

◆ CreateHistogramCallback

◆ DcheckErrorCallback

◆ DeserializeEmbedderFieldsCallback

◆ EntropySource

◆ ExtensionCallback

◆ FailedAccessCheckCallback

◆ FatalErrorCallback

◆ FunctionCallback

◆ GCCallback

◆ GenericNamedPropertyDefinerCallback

◆ GenericNamedPropertyDeleterCallback

◆ GenericNamedPropertyDescriptorCallback

◆ GenericNamedPropertyEnumeratorCallback

◆ GenericNamedPropertyGetterCallback

◆ GenericNamedPropertyQueryCallback

◆ GenericNamedPropertySetterCallback

◆ Handle

◆ HostCreateShadowRealmContextCallback

◆ HostImportModuleDynamicallyCallback

◆ HostImportModuleDynamicallyWithImportAssertionsCallback

◆ HostInitializeImportMetaObjectCallback

◆ IndexedPropertyDefinerCallback

◆ IndexedPropertyDeleterCallback

◆ IndexedPropertyDescriptorCallback

◆ IndexedPropertyEnumeratorCallback

◆ IndexedPropertyGetterCallback

◆ IndexedPropertyQueryCallback

◆ IndexedPropertySetterCallback

◆ InterruptCallback

◆ JitCodeEventHandler

◆ LogEventCallback

◆ MessageCallback

◆ MicrotaskCallback

◆ MicrotasksCompletedCallbackWithData

◆ ModifyCodeGenerationFromStringsCallback

◆ ModifyCodeGenerationFromStringsCallback2

◆ NativeObject

◆ NearHeapLimitCallback

◆ OOMErrorCallback

◆ PersistentContainerValue

◆ PlatformSharedMemoryHandle

◆ PrepareStackTraceCallback

◆ PromiseHook

◆ PromiseRejectCallback

◆ ReturnAddressLocationResolver

◆ SerializeEmbedderFieldsCallback

◆ SharedArrayBufferConstructorEnabledCallback

◆ SnapshotObjectId

◆ UniquePersistent

◆ WasmDynamicTieringEnabledCallback

◆ WasmExceptionsEnabledCallback

◆ WasmLoadSourceMapCallback

◆ WasmSimdEnabledCallback

◆ WasmStreamingCallback

Enumeration Type Documentation

◆ AccessControl

◆ AccessType