1 files changed, 224 insertions, 0 deletions
diff --git a/js/src/builtin/DataViewObject.h b/js/src/builtin/DataViewObject.h
new file mode 100644
index 0000000000..a17b3e1174
--- /dev/null
+++ b/js/src/builtin/DataViewObject.h
@@ -0,0 +1,224 @@
+/* -*- 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 */