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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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef vm_DataViewObject_h
#define vm_DataViewObject_h
#include "mozilla/CheckedInt.h"
#include "mozilla/Maybe.h"
#include "js/Class.h"
#include "vm/ArrayBufferViewObject.h"
#include "vm/JSObject.h"
namespace js {
class ArrayBufferObjectMaybeShared;
// In the DataViewObject, the private slot contains a raw pointer into
// the buffer. The buffer may be shared memory and the raw pointer
// should not be exposed without sharedness information accompanying
// it.
//
// DataViewObject is an abstract base class and has exactly two concrete
// subclasses, FixedLengthDataViewObject and ResizableDataViewObject.
class DataViewObject : public ArrayBufferViewObject {
protected:
static const ClassSpec classSpec_;
private:
template <typename NativeType>
SharedMem<uint8_t*> getDataPointer(uint64_t offset, size_t length,
bool* isSharedMemory);
static bool bufferGetterImpl(JSContext* cx, const CallArgs& args);
static bool bufferGetter(JSContext* cx, unsigned argc, Value* vp);
static bool byteLengthGetterImpl(JSContext* cx, const CallArgs& args);
static bool byteLengthGetter(JSContext* cx, unsigned argc, Value* vp);
static bool byteOffsetGetterImpl(JSContext* cx, const CallArgs& args);
static bool byteOffsetGetter(JSContext* cx, unsigned argc, Value* vp);
static bool getAndCheckConstructorArgs(JSContext* cx, HandleObject bufobj,
const CallArgs& args,
size_t* byteOffsetPtr,
size_t* byteLengthPtr,
bool* autoLengthPtr);
static bool constructSameCompartment(JSContext* cx, HandleObject bufobj,
const CallArgs& args);
static bool constructWrapped(JSContext* cx, HandleObject bufobj,
const CallArgs& args);
static DataViewObject* create(
JSContext* cx, size_t byteOffset, size_t byteLength,
Handle<ArrayBufferObjectMaybeShared*> arrayBuffer, HandleObject proto);
protected:
size_t rawByteLength() const {
return size_t(getFixedSlot(LENGTH_SLOT).toPrivate());
}
public:
static const JSClass protoClass_;
mozilla::Maybe<size_t> byteLength();
mozilla::Maybe<size_t> byteOffset();
template <typename NativeType>
static bool offsetIsInBounds(uint64_t offset, size_t byteLength) {
return offsetIsInBounds(sizeof(NativeType), offset, byteLength);
}
static bool offsetIsInBounds(uint32_t byteSize, uint64_t offset,
size_t byteLength) {
MOZ_ASSERT(byteSize <= 8);
mozilla::CheckedInt<uint64_t> endOffset(offset);
endOffset += byteSize;
return endOffset.isValid() && endOffset.value() <= byteLength;
}
static bool isOriginalByteOffsetGetter(Native native) {
return native == byteOffsetGetter;
}
static bool isOriginalByteLengthGetter(Native native) {
return native == byteLengthGetter;
}
static bool construct(JSContext* cx, unsigned argc, Value* vp);
static bool getInt8Impl(JSContext* cx, const CallArgs& args);
static bool fun_getInt8(JSContext* cx, unsigned argc, Value* vp);
static bool getUint8Impl(JSContext* cx, const CallArgs& args);
static bool fun_getUint8(JSContext* cx, unsigned argc, Value* vp);
static bool getInt16Impl(JSContext* cx, const CallArgs& args);
static bool fun_getInt16(JSContext* cx, unsigned argc, Value* vp);
static bool getUint16Impl(JSContext* cx, const CallArgs& args);
static bool fun_getUint16(JSContext* cx, unsigned argc, Value* vp);
static bool getInt32Impl(JSContext* cx, const CallArgs& args);
static bool fun_getInt32(JSContext* cx, unsigned argc, Value* vp);
static bool getUint32Impl(JSContext* cx, const CallArgs& args);
static bool fun_getUint32(JSContext* cx, unsigned argc, Value* vp);
static bool getBigInt64Impl(JSContext* cx, const CallArgs& args);
static bool fun_getBigInt64(JSContext* cx, unsigned argc, Value* vp);
static bool getBigUint64Impl(JSContext* cx, const CallArgs& args);
static bool fun_getBigUint64(JSContext* cx, unsigned argc, Value* vp);
static bool getFloat32Impl(JSContext* cx, const CallArgs& args);
static bool fun_getFloat32(JSContext* cx, unsigned argc, Value* vp);
static bool getFloat64Impl(JSContext* cx, const CallArgs& args);
static bool fun_getFloat64(JSContext* cx, unsigned argc, Value* vp);
static bool setInt8Impl(JSContext* cx, const CallArgs& args);
static bool fun_setInt8(JSContext* cx, unsigned argc, Value* vp);
static bool setUint8Impl(JSContext* cx, const CallArgs& args);
static bool fun_setUint8(JSContext* cx, unsigned argc, Value* vp);
static bool setInt16Impl(JSContext* cx, const CallArgs& args);
static bool fun_setInt16(JSContext* cx, unsigned argc, Value* vp);
static bool setUint16Impl(JSContext* cx, const CallArgs& args);
static bool fun_setUint16(JSContext* cx, unsigned argc, Value* vp);
static bool setInt32Impl(JSContext* cx, const CallArgs& args);
static bool fun_setInt32(JSContext* cx, unsigned argc, Value* vp);
static bool setUint32Impl(JSContext* cx, const CallArgs& args);
static bool fun_setUint32(JSContext* cx, unsigned argc, Value* vp);
static bool setBigInt64Impl(JSContext* cx, const CallArgs& args);
static bool fun_setBigInt64(JSContext* cx, unsigned argc, Value* vp);
static bool setBigUint64Impl(JSContext* cx, const CallArgs& args);
static bool fun_setBigUint64(JSContext* cx, unsigned argc, Value* vp);
static bool setFloat32Impl(JSContext* cx, const CallArgs& args);
static bool fun_setFloat32(JSContext* cx, unsigned argc, Value* vp);
static bool setFloat64Impl(JSContext* cx, const CallArgs& args);
static bool fun_setFloat64(JSContext* cx, unsigned argc, Value* vp);
template <typename NativeType>
NativeType read(uint64_t offset, size_t length, bool isLittleEndian);
template <typename NativeType>
static bool read(JSContext* cx, Handle<DataViewObject*> obj,
const CallArgs& args, NativeType* val);
template <typename NativeType>
static bool write(JSContext* cx, Handle<DataViewObject*> obj,
const CallArgs& args);
private:
static const JSFunctionSpec methods[];
static const JSPropertySpec properties[];
};
/**
* DataView whose buffer is a fixed-length (Shared)ArrayBuffer object.
*/
class FixedLengthDataViewObject : public DataViewObject {
public:
static const JSClass class_;
size_t byteOffset() const { return ArrayBufferViewObject::byteOffset(); }
size_t byteLength() const { return rawByteLength(); }
bool offsetIsInBounds(uint32_t byteSize, uint64_t offset) const {
return DataViewObject::offsetIsInBounds(byteSize, offset, byteLength());
}
template <typename NativeType>
NativeType read(uint64_t offset, bool isLittleEndian) {
return DataViewObject::read<NativeType>(offset, byteLength(),
isLittleEndian);
}
};
/**
* DataView whose buffer is a resizable (Shared)ArrayBuffer object.
*/
class ResizableDataViewObject : public DataViewObject {
friend class DataViewObject;
static ResizableDataViewObject* create(
JSContext* cx, size_t byteOffset, size_t byteLength, bool autoLength,
Handle<ArrayBufferObjectMaybeShared*> arrayBuffer, HandleObject proto);
public:
static const uint8_t AUTO_LENGTH_SLOT = DataViewObject::RESERVED_SLOTS;
static const uint8_t RESERVED_SLOTS = DataViewObject::RESERVED_SLOTS + 1;
static const JSClass class_;
bool isAutoLength() const {
return getFixedSlot(AUTO_LENGTH_SLOT).toBoolean();
}
};
// For structured cloning.
JSObject* NewDataView(JSContext* cx, HandleObject buffer, size_t byteOffset);
} // namespace js
template <>
inline bool JSObject::is<js::DataViewObject>() const {
return is<js::FixedLengthDataViewObject>() ||
is<js::ResizableDataViewObject>();
}
#endif /* vm_DataViewObject_h */
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