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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=8 sts=2 et sw=2 tw=80:
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
/*
* Typed array, ArrayBuffer, and DataView creation, predicate, and accessor
* functions.
*/
#ifndef js_experimental_TypedData_h
#define js_experimental_TypedData_h
#include "mozilla/Assertions.h" // MOZ_ASSERT, MOZ_CRASH
#include "mozilla/Casting.h" // mozilla::AssertedCast
#include "mozilla/Span.h"
#include <stddef.h> // size_t
#include <stdint.h> // {,u}int8_t, {,u}int16_t, {,u}int32_t
#include "jstypes.h" // JS_PUBLIC_API
#include "js/Object.h" // JS::GetClass, JS::GetReservedSlot, JS::GetMaybePtrFromReservedSlot
#include "js/RootingAPI.h" // JS::Handle, JS_DECLARE_IS_HEAP_CONSTRUCTIBLE_TYPE
#include "js/ScalarType.h" // JS::Scalar::Type
#include "js/Wrapper.h" // js::CheckedUnwrapStatic
struct JSClass;
class JS_PUBLIC_API JSObject;
namespace JS {
class JS_PUBLIC_API AutoRequireNoGC;
} // namespace JS
// JS_FOR_EACH_TYPED_ARRAY(MACRO) expands MACRO once for each specific
// typed array subtype (Int8Array, Float64Array, ...), passing arguments
// as MACRO(ExternalT, NativeT, Name) where
//
// ExternalT - externally-exposed element type (eg uint8_t)
//
// NativeT - element type used for the implementation (eg js::uint8_clamped_t)
// Note that this type is not exposed publicly. Internal files need to
// #include <vm/Uint8Clamped.h> to see it.
//
// Name - a name usable as both a JS::Scalar::Type value (eg
// JS::Scalar::Uint8Clamped) or the stem of a full typed array name (eg
// Uint8ClampedArray)
//
#define JS_FOR_EACH_TYPED_ARRAY(MACRO) \
MACRO(int8_t, int8_t, Int8) \
MACRO(uint8_t, uint8_t, Uint8) \
MACRO(int16_t, int16_t, Int16) \
MACRO(uint16_t, uint16_t, Uint16) \
MACRO(int32_t, int32_t, Int32) \
MACRO(uint32_t, uint32_t, Uint32) \
MACRO(float, float, Float32) \
MACRO(double, double, Float64) \
MACRO(uint8_t, js::uint8_clamped, Uint8Clamped) \
MACRO(int64_t, int64_t, BigInt64) \
MACRO(uint64_t, uint64_t, BigUint64)
/*
* JS_New(type)Array:
*
* Create a new typed array with nelements elements.
*
* These functions (except the WithBuffer variants) fill in the array with
* zeros.
*
* JS_New(type)ArrayFromArray:
*
* Create a new typed array and copy in values from the given object. The
* object is used as if it were an array; that is, the new array (if
* successfully created) will have length given by array.length, and its
* elements will be those specified by array[0], array[1], and so on, after
* conversion to the typed array element type.
*
* JS_New(type)ArrayWithBuffer:
*
* Create a new typed array using the given ArrayBuffer or
* SharedArrayBuffer for storage. The length value is optional; if -1
* is passed, enough elements to use up the remainder of the byte
* array is used as the default value.
*/
#define DECLARE_TYPED_ARRAY_CREATION_API(ExternalType, NativeType, Name) \
extern JS_PUBLIC_API JSObject* JS_New##Name##Array(JSContext* cx, \
size_t nelements); \
extern JS_PUBLIC_API JSObject* JS_New##Name##ArrayFromArray( \
JSContext* cx, JS::Handle<JSObject*> array); \
extern JS_PUBLIC_API JSObject* JS_New##Name##ArrayWithBuffer( \
JSContext* cx, JS::Handle<JSObject*> arrayBuffer, size_t byteOffset, \
int64_t length);
JS_FOR_EACH_TYPED_ARRAY(DECLARE_TYPED_ARRAY_CREATION_API)
#undef DECLARE_TYPED_ARRAY_CREATION_API
/**
* Check whether obj supports JS_GetTypedArray* APIs. Note that this may return
* false if a security wrapper is encountered that denies the unwrapping. If
* this test or one of the JS_Is*Array tests succeeds, then it is safe to call
* the various accessor JSAPI calls defined below.
*/
extern JS_PUBLIC_API bool JS_IsTypedArrayObject(JSObject* obj);
/**
* Check whether obj supports JS_GetArrayBufferView* APIs. Note that this may
* return false if a security wrapper is encountered that denies the
* unwrapping. If this test or one of the more specific tests succeeds, then it
* is safe to call the various ArrayBufferView accessor JSAPI calls defined
* below.
*/
extern JS_PUBLIC_API bool JS_IsArrayBufferViewObject(JSObject* obj);
/**
* Return the isShared flag of a typed array, which denotes whether
* the underlying buffer is a SharedArrayBuffer.
*
* |obj| must have passed a JS_IsTypedArrayObject/JS_Is*Array test, or somehow
* be known that it would pass such a test: it is a typed array or a wrapper of
* a typed array, and the unwrapping will succeed.
*/
extern JS_PUBLIC_API bool JS_GetTypedArraySharedness(JSObject* obj);
/*
* Test for specific typed array types (ArrayBufferView subtypes) and return
* the unwrapped object if so, else nullptr. Never throws.
*/
namespace js {
extern JS_PUBLIC_API JSObject* UnwrapArrayBufferView(JSObject* obj);
extern JS_PUBLIC_API JSObject* UnwrapReadableStream(JSObject* obj);
namespace detail {
constexpr size_t TypedArrayLengthSlot = 1;
constexpr size_t TypedArrayDataSlot = 3;
} // namespace detail
// This one isn't inlined because it's rather tricky (by dint of having to deal
// with a dozen-plus classes and varying slot layouts.
extern JS_PUBLIC_API void GetArrayBufferViewLengthAndData(JSObject* obj,
size_t* length,
bool* isSharedMemory,
uint8_t** data);
} // namespace js
/*
* JS_GetObjectAs(type)Array(JSObject* maybeWrapped, size_t* length, bool*
* isSharedMemory, element_type** data)
*
* Unwrap Typed arrays all at once. Return nullptr without throwing if the
* object cannot be viewed as the correct typed array, or the typed array
* object on success, filling both outparameters.
*/
#define DECLARE_GET_OBJECT_AS(ExternalType, NativeType, Name) \
extern JS_PUBLIC_API JSObject* JS_GetObjectAs##Name##Array( \
JSObject* maybeWrapped, size_t* length, bool* isSharedMemory, \
ExternalType** data);
JS_FOR_EACH_TYPED_ARRAY(DECLARE_GET_OBJECT_AS)
#undef DECLARE_GET_OBJECT_AS
extern JS_PUBLIC_API JSObject* JS_GetObjectAsArrayBufferView(
JSObject* obj, size_t* length, bool* isSharedMemory, uint8_t** data);
/*
* Get the type of elements in a typed array, or MaxTypedArrayViewType if a
* DataView.
*
* |obj| must have passed a JS_IsArrayBufferView/JS_Is*Array test, or somehow
* be known that it would pass such a test: it is an ArrayBufferView or a
* wrapper of an ArrayBufferView, and the unwrapping will succeed.
*/
extern JS_PUBLIC_API JS::Scalar::Type JS_GetArrayBufferViewType(JSObject* obj);
/**
* Return the number of elements in a typed array.
*
* |obj| must have passed a JS_IsTypedArrayObject/JS_Is*Array test, or somehow
* be known that it would pass such a test: it is a typed array or a wrapper of
* a typed array, and the unwrapping will succeed.
*/
extern JS_PUBLIC_API size_t JS_GetTypedArrayLength(JSObject* obj);
/**
* Return the byte offset from the start of an ArrayBuffer to the start of a
* typed array view.
*
* |obj| must have passed a JS_IsTypedArrayObject/JS_Is*Array test, or somehow
* be known that it would pass such a test: it is a typed array or a wrapper of
* a typed array, and the unwrapping will succeed.
*/
extern JS_PUBLIC_API size_t JS_GetTypedArrayByteOffset(JSObject* obj);
/**
* Return the byte length of a typed array.
*
* |obj| must have passed a JS_IsTypedArrayObject/JS_Is*Array test, or somehow
* be known that it would pass such a test: it is a typed array or a wrapper of
* a typed array, and the unwrapping will succeed.
*/
extern JS_PUBLIC_API size_t JS_GetTypedArrayByteLength(JSObject* obj);
/**
* More generic name for JS_GetTypedArrayByteLength to cover DataViews as well
*/
extern JS_PUBLIC_API size_t JS_GetArrayBufferViewByteLength(JSObject* obj);
/**
* More generic name for JS_GetTypedArrayByteOffset to cover DataViews as well
*/
extern JS_PUBLIC_API size_t JS_GetArrayBufferViewByteOffset(JSObject* obj);
/**
* Same as above, but for any kind of ArrayBufferView. Prefer the type-specific
* versions when possible.
*/
extern JS_PUBLIC_API void* JS_GetArrayBufferViewData(
JSObject* obj, bool* isSharedMemory, const JS::AutoRequireNoGC&);
/**
* Return a "fixed" pointer (one that will not move during a GC) to the
* ArrayBufferView's data. Note that this will not keep the object alive; the
* holding object should be rooted or traced. If the view is storing the data
* inline, this will copy the data to the provided buffer, returning nullptr if
* bufSize is inadequate.
*
* Avoid using this unless necessary. JS_GetArrayBufferViewData is simpler and
* more efficient because it requires the caller to ensure that a GC will not
* occur and thus does not need to handle movable data.
*/
extern JS_PUBLIC_API uint8_t* JS_GetArrayBufferViewFixedData(JSObject* obj,
uint8_t* buffer,
size_t bufSize);
/**
* If the bufSize passed to JS_GetArrayBufferViewFixedData is at least this
* many bytes, then any copied data is guaranteed to fit into the provided
* buffer.
*/
extern JS_PUBLIC_API size_t JS_MaxMovableTypedArraySize();
/**
* Return the ArrayBuffer or SharedArrayBuffer underlying an ArrayBufferView.
* This may return a detached buffer. |obj| must be an object that would
* return true for JS_IsArrayBufferViewObject().
*/
extern JS_PUBLIC_API JSObject* JS_GetArrayBufferViewBuffer(
JSContext* cx, JS::Handle<JSObject*> obj, bool* isSharedMemory);
/**
* Create a new DataView using the given buffer for storage. The given buffer
* must be an ArrayBuffer or SharedArrayBuffer (or a cross-compartment wrapper
* of either type), and the offset and length must fit within the bounds of the
* buffer. Currently, nullptr will be returned and an exception will be thrown
* if these conditions do not hold, but do not depend on that behavior.
*/
JS_PUBLIC_API JSObject* JS_NewDataView(JSContext* cx,
JS::Handle<JSObject*> buffer,
size_t byteOffset, size_t byteLength);
namespace JS {
/*
* Returns whether the passed array buffer view is 'large': its byteLength >= 2
* GB.
*
* |obj| must pass a JS_IsArrayBufferViewObject test.
*/
JS_PUBLIC_API bool IsLargeArrayBufferView(JSObject* obj);
/*
* Returns whether the passed array buffer view has a resizable or growable
* array buffer.
*
* |obj| must pass a JS_IsArrayBufferViewObject test.
*/
JS_PUBLIC_API bool IsResizableArrayBufferView(JSObject* obj);
/*
* Given an ArrayBuffer or view, prevent the length of the underlying
* ArrayBuffer from changing (with pin=true) until unfrozen (with
* pin=false). Note that some objects (eg SharedArrayBuffers) cannot change
* length to begin with, and are treated as always pinned.
*
* ArrayBuffers and their views can change length by being detached, or
* if they are ResizableArrayBuffers or (shared) GrowableArrayBuffers.
*
* Returns whether the pinned status changed.
*/
JS_PUBLIC_API bool PinArrayBufferOrViewLength(JSObject* obj, bool pin);
/*
* Given an ArrayBuffer or view, make sure its contents are not stored inline
* so that the data is safe for use even if a GC moves the owning object.
*
* Note that this by itself does not make it safe to use the data pointer
* if JS can run or the ArrayBuffer can be detached in any way. Consider using
* this in conjunction with PinArrayBufferOrViewLength, which will cause any
* potentially invalidating operations to fail.
*/
JS_PUBLIC_API bool EnsureNonInlineArrayBufferOrView(JSContext* cx,
JSObject* obj);
namespace detail {
// Map from eg Uint8Clamped -> uint8_t, Uint8 -> uint8_t, or Float64 ->
// double. Used as the DataType within a JS::TypedArray specialization.
template <JS::Scalar::Type ArrayType>
struct ExternalTypeOf {};
#define DEFINE_ELEMENT_TYPES(ExternalT, NativeT, Name) \
template <> \
struct ExternalTypeOf<JS::Scalar::Name> { \
using Type = ExternalT; \
};
JS_FOR_EACH_TYPED_ARRAY(DEFINE_ELEMENT_TYPES)
#undef DEFINE_ELEMENT_TYPES
template <JS::Scalar::Type ArrayType>
using ExternalTypeOf_t = typename ExternalTypeOf<ArrayType>::Type;
} // namespace detail
// A class holding a JSObject referring to a buffer of data. Either an
// ArrayBufferObject or some sort of ArrayBufferViewObject (see below).
// Note that this will always hold an unwrapped object.
class JS_PUBLIC_API ArrayBufferOrView {
public:
// Typed Arrays will set this to their specific element type.
// Everything else just claims to expose things as uint8_t*.
using DataType = uint8_t;
protected:
JSObject* obj;
explicit ArrayBufferOrView(JSObject* unwrapped) : obj(unwrapped) {}
public:
// ArrayBufferOrView subclasses will set `obj` to nullptr if wrapping an
// object of the wrong type. So this allows:
//
// auto view = JS::TypedArray<JS::Scalar::Int8>::fromObject(obj);
// if (!view) { ... }
//
explicit operator bool() const { return !!obj; }
// `obj` must be an unwrapped ArrayBuffer or view, or nullptr.
static inline ArrayBufferOrView fromObject(JSObject* unwrapped);
// Unwrap an ArrayBuffer or view. Returns ArrayBufferOrView(nullptr) if
// `maybeWrapped` is the wrong type or fails unwrapping. Never throw.
static ArrayBufferOrView unwrap(JSObject* maybeWrapped);
// Allow use as Rooted<JS::ArrayBufferOrView>.
void trace(JSTracer* trc) {
if (obj) {
js::gc::TraceExternalEdge(trc, &obj, "ArrayBufferOrView object");
}
}
bool isDetached() const;
bool isResizable() const;
void exposeToActiveJS() const {
if (obj) {
js::BarrierMethods<JSObject*>::exposeToJS(obj);
}
}
JSObject* asObject() const {
exposeToActiveJS();
return obj;
}
JSObject* asObjectUnbarriered() const { return obj; }
JSObject** addressOfObject() { return &obj; }
bool operator==(const ArrayBufferOrView& other) const {
return obj == other.asObjectUnbarriered();
}
bool operator!=(const ArrayBufferOrView& other) const {
return obj != other.asObjectUnbarriered();
}
};
class JS_PUBLIC_API ArrayBuffer : public ArrayBufferOrView {
static const JSClass* const FixedLengthUnsharedClass;
static const JSClass* const ResizableUnsharedClass;
static const JSClass* const FixedLengthSharedClass;
static const JSClass* const GrowableSharedClass;
protected:
explicit ArrayBuffer(JSObject* unwrapped) : ArrayBufferOrView(unwrapped) {}
public:
static ArrayBuffer fromObject(JSObject* unwrapped) {
if (unwrapped) {
const JSClass* clasp = GetClass(unwrapped);
if (clasp == FixedLengthUnsharedClass ||
clasp == ResizableUnsharedClass || clasp == FixedLengthSharedClass ||
clasp == GrowableSharedClass) {
return ArrayBuffer(unwrapped);
}
}
return ArrayBuffer(nullptr);
}
static ArrayBuffer unwrap(JSObject* maybeWrapped);
static ArrayBuffer create(JSContext* cx, size_t nbytes);
mozilla::Span<uint8_t> getData(bool* isSharedMemory,
const JS::AutoRequireNoGC&);
};
// A view into an ArrayBuffer, either a DataViewObject or a Typed Array variant.
class JS_PUBLIC_API ArrayBufferView : public ArrayBufferOrView {
protected:
explicit ArrayBufferView(JSObject* unwrapped)
: ArrayBufferOrView(unwrapped) {}
public:
static inline ArrayBufferView fromObject(JSObject* unwrapped);
static ArrayBufferView unwrap(JSObject* maybeWrapped) {
if (!maybeWrapped) {
return ArrayBufferView(nullptr);
}
ArrayBufferView view = fromObject(maybeWrapped);
if (view) {
return view;
}
return fromObject(js::CheckedUnwrapStatic(maybeWrapped));
}
bool isDetached() const;
bool isResizable() const;
mozilla::Span<uint8_t> getData(bool* isSharedMemory,
const JS::AutoRequireNoGC&);
// Must only be called if !isDetached().
size_t getByteLength(const JS::AutoRequireNoGC&);
};
class JS_PUBLIC_API DataView : public ArrayBufferView {
static const JSClass* const FixedLengthClassPtr;
static const JSClass* const ResizableClassPtr;
protected:
explicit DataView(JSObject* unwrapped) : ArrayBufferView(unwrapped) {}
public:
static DataView fromObject(JSObject* unwrapped) {
if (unwrapped) {
const JSClass* clasp = GetClass(unwrapped);
if (clasp == FixedLengthClassPtr || clasp == ResizableClassPtr) {
return DataView(unwrapped);
}
}
return DataView(nullptr);
}
static DataView unwrap(JSObject* maybeWrapped) {
if (!maybeWrapped) {
return DataView(nullptr);
}
DataView view = fromObject(maybeWrapped);
if (view) {
return view;
}
return fromObject(js::CheckedUnwrapStatic(maybeWrapped));
}
};
// Base type of all Typed Array variants.
class JS_PUBLIC_API TypedArray_base : public ArrayBufferView {
protected:
explicit TypedArray_base(JSObject* unwrapped) : ArrayBufferView(unwrapped) {}
static const JSClass* const fixedLengthClasses;
static const JSClass* const resizableClasses;
public:
static TypedArray_base fromObject(JSObject* unwrapped);
static TypedArray_base unwrap(JSObject* maybeWrapped) {
if (!maybeWrapped) {
return TypedArray_base(nullptr);
}
TypedArray_base view = fromObject(maybeWrapped);
if (view) {
return view;
}
return fromObject(js::CheckedUnwrapStatic(maybeWrapped));
}
};
template <JS::Scalar::Type TypedArrayElementType>
class JS_PUBLIC_API TypedArray : public TypedArray_base {
// This cannot be a static data member because on Windows,
// __declspec(dllexport) causes the class to be instantiated immediately,
// leading to errors when later explicit specializations of inline member
// functions are encountered ("error: explicit specialization of 'ClassPtr'
// after instantiation"). And those inlines need to be defined outside of the
// class due to order dependencies. This is the only way I could get it to
// work on both Windows and POSIX.
static const JSClass* fixedLengthClasp() {
return &TypedArray_base::fixedLengthClasses[static_cast<int>(
TypedArrayElementType)];
}
static const JSClass* resizableClasp() {
return &TypedArray_base::resizableClasses[static_cast<int>(
TypedArrayElementType)];
}
protected:
explicit TypedArray(JSObject* unwrapped) : TypedArray_base(unwrapped) {}
public:
using DataType = detail::ExternalTypeOf_t<TypedArrayElementType>;
static constexpr JS::Scalar::Type Scalar = TypedArrayElementType;
static TypedArray create(JSContext* cx, size_t nelements);
static TypedArray fromArray(JSContext* cx, HandleObject other);
static TypedArray fromBuffer(JSContext* cx, HandleObject arrayBuffer,
size_t byteOffset, int64_t length);
// Return an interface wrapper around `obj`, or around nullptr if `obj` is not
// an unwrapped typed array of the correct type.
static TypedArray fromObject(JSObject* unwrapped) {
if (unwrapped) {
const JSClass* clasp = GetClass(unwrapped);
if (clasp == fixedLengthClasp() || clasp == resizableClasp()) {
return TypedArray(unwrapped);
}
}
return TypedArray(nullptr);
}
static TypedArray unwrap(JSObject* maybeWrapped) {
if (!maybeWrapped) {
return TypedArray(nullptr);
}
TypedArray view = fromObject(maybeWrapped);
if (view) {
return view;
}
return fromObject(js::CheckedUnwrapStatic(maybeWrapped));
}
// Return a pointer to the start of the data referenced by a typed array. The
// data is still owned by the typed array, and should not be modified on
// another thread. Furthermore, the pointer can become invalid on GC (if the
// data is small and fits inside the array's GC header), so callers must take
// care not to hold on across anything that could GC.
//
// |obj| must have passed a JS_Is*Array test, or somehow be known that it
// would pass such a test: it is a typed array or a wrapper of a typed array,
// and the unwrapping will succeed.
//
// |*isSharedMemory| will be set to true if the typed array maps a
// SharedArrayBuffer, otherwise to false.
//
mozilla::Span<DataType> getData(bool* isSharedMemory,
const JS::AutoRequireNoGC& nogc);
};
ArrayBufferOrView ArrayBufferOrView::fromObject(JSObject* unwrapped) {
if (ArrayBuffer::fromObject(unwrapped) ||
ArrayBufferView::fromObject(unwrapped)) {
return ArrayBufferOrView(unwrapped);
}
return ArrayBufferOrView(nullptr);
}
ArrayBufferView ArrayBufferView::fromObject(JSObject* unwrapped) {
if (TypedArray_base::fromObject(unwrapped) ||
DataView::fromObject(unwrapped)) {
return ArrayBufferView(unwrapped);
}
return ArrayBufferView(nullptr);
}
} /* namespace JS */
/*
* JS_Get(type)ArrayData(JSObject* obj,
* bool* isSharedMemory,
* const JS::AutoRequireNoGC&)
*
* js::Get(type)ArrayLengthAndData(JSObject* obj,
* size_t* length,
* bool* isSharedMemory,
* const JS::AutoRequireNoGC&)
*
* Return a pointer to the start of the data referenced by a typed array. The
* data is still owned by the typed array, and should not be modified on
* another thread. Furthermore, the pointer can become invalid on GC (if the
* data is small and fits inside the array's GC header), so callers must take
* care not to hold on across anything that could GC.
*
* |obj| must have passed a JS_Is*Array test, or somehow be known that it would
* pass such a test: it is a typed array or a wrapper of a typed array, and the
* unwrapping will succeed.
*
* |*isSharedMemory| will be set to true if the typed array maps a
* SharedArrayBuffer, otherwise to false.
*/
#define JS_DEFINE_DATA_AND_LENGTH_ACCESSOR(ExternalType, NativeType, Name) \
extern JS_PUBLIC_API ExternalType* JS_Get##Name##ArrayData( \
JSObject* maybeWrapped, bool* isSharedMemory, \
const JS::AutoRequireNoGC&); \
\
namespace js { \
inline void Get##Name##ArrayLengthAndData(JSObject* unwrapped, \
size_t* length, \
bool* isSharedMemory, \
ExternalType** data) { \
MOZ_ASSERT(JS::TypedArray<JS::Scalar::Name>::fromObject(unwrapped)); \
const JS::Value& lenSlot = \
JS::GetReservedSlot(unwrapped, detail::TypedArrayLengthSlot); \
*length = size_t(lenSlot.toPrivate()); \
*isSharedMemory = JS_GetTypedArraySharedness(unwrapped); \
*data = JS::GetMaybePtrFromReservedSlot<ExternalType>( \
unwrapped, detail::TypedArrayDataSlot); \
} \
\
JS_PUBLIC_API JSObject* Unwrap##Name##Array(JSObject* maybeWrapped); \
} /* namespace js */
JS_FOR_EACH_TYPED_ARRAY(JS_DEFINE_DATA_AND_LENGTH_ACCESSOR)
#undef JS_DEFINE_DATA_AND_LENGTH_ACCESSOR
namespace JS {
#define IMPL_TYPED_ARRAY_CLASS(ExternalType, NativeType, Name) \
template <> \
inline JS::TypedArray<JS::Scalar::Name> \
JS::TypedArray<JS::Scalar::Name>::create(JSContext* cx, size_t nelements) { \
return fromObject(JS_New##Name##Array(cx, nelements)); \
}; \
\
template <> \
inline JS::TypedArray<JS::Scalar::Name> \
JS::TypedArray<JS::Scalar::Name>::fromArray(JSContext* cx, \
HandleObject other) { \
return fromObject(JS_New##Name##ArrayFromArray(cx, other)); \
}; \
\
template <> \
inline JS::TypedArray<JS::Scalar::Name> \
JS::TypedArray<JS::Scalar::Name>::fromBuffer( \
JSContext* cx, HandleObject arrayBuffer, size_t byteOffset, \
int64_t length) { \
return fromObject( \
JS_New##Name##ArrayWithBuffer(cx, arrayBuffer, byteOffset, length)); \
};
JS_FOR_EACH_TYPED_ARRAY(IMPL_TYPED_ARRAY_CLASS)
#undef IMPL_TYPED_ARRAY_CLASS
// Create simple names like Int8Array, Float32Array, etc.
#define JS_DECLARE_CLASS_ALIAS(ExternalType, NativeType, Name) \
using Name##Array = TypedArray<js::Scalar::Name>;
JS_FOR_EACH_TYPED_ARRAY(JS_DECLARE_CLASS_ALIAS)
#undef JS_DECLARE_CLASS_ALIAS
} // namespace JS
namespace js {
template <typename T>
using EnableIfABOVType =
std::enable_if_t<std::is_base_of_v<JS::ArrayBufferOrView, T>>;
template <typename T, typename Wrapper>
class WrappedPtrOperations<T, Wrapper, EnableIfABOVType<T>> {
auto get() const { return static_cast<const Wrapper*>(this)->get(); }
public:
explicit operator bool() const { return bool(get()); }
JSObject* asObject() const { return get().asObject(); }
bool isDetached() const { return get().isDetached(); }
bool isSharedMemory() const { return get().isSharedMemory(); }
mozilla::Span<typename T::DataType> getData(bool* isSharedMemory,
const JS::AutoRequireNoGC& nogc) {
return get().getData(isSharedMemory, nogc);
}
};
// Allow usage within Heap<T>.
template <typename T>
struct IsHeapConstructibleType<T, EnableIfABOVType<T>> : public std::true_type {
};
template <typename T>
struct BarrierMethods<T, EnableIfABOVType<T>> {
static gc::Cell* asGCThingOrNull(T view) {
return reinterpret_cast<gc::Cell*>(view.asObjectUnbarriered());
}
static void postWriteBarrier(T* viewp, T prev, T next) {
BarrierMethods<JSObject*>::postWriteBarrier(viewp->addressOfObject(),
prev.asObjectUnbarriered(),
next.asObjectUnbarriered());
}
static void exposeToJS(T view) { view.exposeToActiveJS(); }
static void readBarrier(T view) {
JSObject* obj = view.asObjectUnbarriered();
if (obj) {
js::gc::IncrementalReadBarrier(JS::GCCellPtr(obj));
}
}
};
} // namespace js
namespace JS {
template <typename T>
struct SafelyInitialized<T, js::EnableIfABOVType<T>> {
static T create() { return T::fromObject(nullptr); }
};
} // namespace JS
/*
* JS_Is(type)Array(JSObject* maybeWrapped)
*
* Test for specific typed array types.
*/
#define DECLARE_IS_ARRAY_TEST(_1, _2, Name) \
inline JS_PUBLIC_API bool JS_Is##Name##Array(JSObject* maybeWrapped) { \
return JS::TypedArray<js::Scalar::Name>::unwrap(maybeWrapped).asObject(); \
}
JS_FOR_EACH_TYPED_ARRAY(DECLARE_IS_ARRAY_TEST)
#undef DECLARE_IS_ARRAY_TEST
#endif // js_experimental_TypedData_h