michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-*/
michael@0: /* vim: set ts=2 sw=2 et tw=79: */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
michael@0:  * You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef mozilla_dom_TypedArray_h
michael@0: #define mozilla_dom_TypedArray_h
michael@0: 
michael@0: #include "jsapi.h"
michael@0: #include "jsfriendapi.h"
michael@0: #include "js/RootingAPI.h"
michael@0: #include "js/TracingAPI.h"
michael@0: #include "mozilla/Attributes.h"
michael@0: #include "mozilla/Move.h"
michael@0: #include "mozilla/dom/BindingDeclarations.h"
michael@0: #include "nsWrapperCache.h"
michael@0: 
michael@0: namespace mozilla {
michael@0: namespace dom {
michael@0: 
michael@0: /*
michael@0:  * Class that just handles the JSObject storage and tracing for typed arrays
michael@0:  */
michael@0: struct TypedArrayObjectStorage : AllTypedArraysBase {
michael@0: protected:
michael@0:   JSObject* mObj;
michael@0: 
michael@0:   TypedArrayObjectStorage(JSObject *obj) : mObj(obj)
michael@0:   {
michael@0:   }
michael@0: 
michael@0:   explicit TypedArrayObjectStorage(TypedArrayObjectStorage&& aOther)
michael@0:     : mObj(aOther.mObj)
michael@0:   {
michael@0:     aOther.mObj = nullptr;
michael@0:   }
michael@0: 
michael@0: public:
michael@0:   inline void TraceSelf(JSTracer* trc)
michael@0:   {
michael@0:     if (mObj) {
michael@0:       JS_CallObjectTracer(trc, &mObj, "TypedArray.mObj");
michael@0:     }
michael@0:   }
michael@0: 
michael@0: private:
michael@0:   TypedArrayObjectStorage(const TypedArrayObjectStorage&) MOZ_DELETE;
michael@0: };
michael@0: 
michael@0: /*
michael@0:  * Various typed array classes for argument conversion.  We have a base class
michael@0:  * that has a way of initializing a TypedArray from an existing typed array, and
michael@0:  * a subclass of the base class that supports creation of a relevant typed array
michael@0:  * or array buffer object.
michael@0:  */
michael@0: template<typename T,
michael@0:          JSObject* UnwrapArray(JSObject*),
michael@0:          void GetLengthAndData(JSObject*, uint32_t*, T**)>
michael@0: struct TypedArray_base : public TypedArrayObjectStorage {
michael@0:   typedef T element_type;
michael@0: 
michael@0:   TypedArray_base(JSObject* obj)
michael@0:     : TypedArrayObjectStorage(obj),
michael@0:       mData(nullptr),
michael@0:       mLength(0),
michael@0:       mComputed(false)
michael@0:   {
michael@0:     MOZ_ASSERT(obj != nullptr);
michael@0:   }
michael@0: 
michael@0:   TypedArray_base()
michael@0:     : TypedArrayObjectStorage(nullptr),
michael@0:       mData(nullptr),
michael@0:       mLength(0),
michael@0:       mComputed(false)
michael@0:   {
michael@0:   }
michael@0: 
michael@0:   explicit TypedArray_base(TypedArray_base&& aOther)
michael@0:     : TypedArrayObjectStorage(Move(aOther)),
michael@0:       mData(aOther.mData),
michael@0:       mLength(aOther.mLength)
michael@0:   {
michael@0:     aOther.mData = nullptr;
michael@0:     aOther.mLength = 0;
michael@0:   }
michael@0: 
michael@0: private:
michael@0:   mutable T* mData;
michael@0:   mutable uint32_t mLength;
michael@0:   mutable bool mComputed;
michael@0: 
michael@0: public:
michael@0:   inline bool Init(JSObject* obj)
michael@0:   {
michael@0:     MOZ_ASSERT(!inited());
michael@0:     DoInit(obj);
michael@0:     return inited();
michael@0:   }
michael@0: 
michael@0:   inline bool inited() const {
michael@0:     return !!mObj;
michael@0:   }
michael@0: 
michael@0:   inline T *Data() const {
michael@0:     MOZ_ASSERT(mComputed);
michael@0:     return mData;
michael@0:   }
michael@0: 
michael@0:   inline uint32_t Length() const {
michael@0:     MOZ_ASSERT(mComputed);
michael@0:     return mLength;
michael@0:   }
michael@0: 
michael@0:   inline JSObject *Obj() const {
michael@0:     MOZ_ASSERT(inited());
michael@0:     return mObj;
michael@0:   }
michael@0: 
michael@0:   inline bool WrapIntoNewCompartment(JSContext* cx)
michael@0:   {
michael@0:     return JS_WrapObject(cx,
michael@0:       JS::MutableHandle<JSObject*>::fromMarkedLocation(&mObj));
michael@0:   }
michael@0: 
michael@0:   inline void ComputeLengthAndData() const
michael@0:   {
michael@0:     MOZ_ASSERT(inited());
michael@0:     MOZ_ASSERT(!mComputed);
michael@0:     GetLengthAndData(mObj, &mLength, &mData);
michael@0:     mComputed = true;
michael@0:   }
michael@0: 
michael@0: protected:
michael@0:   inline void DoInit(JSObject* obj)
michael@0:   {
michael@0:     mObj = UnwrapArray(obj);
michael@0:   }
michael@0: 
michael@0:   inline void ComputeData() const {
michael@0:     MOZ_ASSERT(inited());
michael@0:     if (!mComputed) {
michael@0:       GetLengthAndData(mObj, &mLength, &mData);
michael@0:       mComputed = true;
michael@0:     }
michael@0:   }
michael@0: 
michael@0: private:
michael@0:   TypedArray_base(const TypedArray_base&) MOZ_DELETE;
michael@0: };
michael@0: 
michael@0: 
michael@0: template<typename T,
michael@0:          JSObject* UnwrapArray(JSObject*),
michael@0:          T* GetData(JSObject*),
michael@0:          void GetLengthAndData(JSObject*, uint32_t*, T**),
michael@0:          JSObject* CreateNew(JSContext*, uint32_t)>
michael@0: struct TypedArray : public TypedArray_base<T, UnwrapArray, GetLengthAndData> {
michael@0:   TypedArray(JSObject* obj) :
michael@0:     TypedArray_base<T, UnwrapArray, GetLengthAndData>(obj)
michael@0:   {}
michael@0: 
michael@0:   TypedArray() :
michael@0:     TypedArray_base<T, UnwrapArray, GetLengthAndData>()
michael@0:   {}
michael@0: 
michael@0:   explicit TypedArray(TypedArray&& aOther)
michael@0:     : TypedArray_base<T, UnwrapArray, GetLengthAndData>(Move(aOther))
michael@0:   {
michael@0:   }
michael@0: 
michael@0:   static inline JSObject*
michael@0:   Create(JSContext* cx, nsWrapperCache* creator, uint32_t length,
michael@0:          const T* data = nullptr) {
michael@0:     JS::Rooted<JSObject*> creatorWrapper(cx);
michael@0:     Maybe<JSAutoCompartment> ac;
michael@0:     if (creator && (creatorWrapper = creator->GetWrapperPreserveColor())) {
michael@0:       ac.construct(cx, creatorWrapper);
michael@0:     }
michael@0: 
michael@0:     return CreateCommon(cx, length, data);
michael@0:   }
michael@0: 
michael@0:   static inline JSObject*
michael@0:   Create(JSContext* cx, uint32_t length, const T* data = nullptr) {
michael@0:     return CreateCommon(cx, length, data);
michael@0:   }
michael@0: 
michael@0: private:
michael@0:   static inline JSObject*
michael@0:   CreateCommon(JSContext* cx, uint32_t length, const T* data) {
michael@0:     JSObject* obj = CreateNew(cx, length);
michael@0:     if (!obj) {
michael@0:       return nullptr;
michael@0:     }
michael@0:     if (data) {
michael@0:       T* buf = static_cast<T*>(GetData(obj));
michael@0:       memcpy(buf, data, length*sizeof(T));
michael@0:     }
michael@0:     return obj;
michael@0:   }
michael@0: 
michael@0:   TypedArray(const TypedArray&) MOZ_DELETE;
michael@0: };
michael@0: 
michael@0: typedef TypedArray<int8_t, js::UnwrapInt8Array, JS_GetInt8ArrayData,
michael@0:                    js::GetInt8ArrayLengthAndData, JS_NewInt8Array>
michael@0:         Int8Array;
michael@0: typedef TypedArray<uint8_t, js::UnwrapUint8Array, JS_GetUint8ArrayData,
michael@0:                    js::GetUint8ArrayLengthAndData, JS_NewUint8Array>
michael@0:         Uint8Array;
michael@0: typedef TypedArray<uint8_t, js::UnwrapUint8ClampedArray, JS_GetUint8ClampedArrayData,
michael@0:                    js::GetUint8ClampedArrayLengthAndData, JS_NewUint8ClampedArray>
michael@0:         Uint8ClampedArray;
michael@0: typedef TypedArray<int16_t, js::UnwrapInt16Array, JS_GetInt16ArrayData,
michael@0:                    js::GetInt16ArrayLengthAndData, JS_NewInt16Array>
michael@0:         Int16Array;
michael@0: typedef TypedArray<uint16_t, js::UnwrapUint16Array, JS_GetUint16ArrayData,
michael@0:                    js::GetUint16ArrayLengthAndData, JS_NewUint16Array>
michael@0:         Uint16Array;
michael@0: typedef TypedArray<int32_t, js::UnwrapInt32Array, JS_GetInt32ArrayData,
michael@0:                    js::GetInt32ArrayLengthAndData, JS_NewInt32Array>
michael@0:         Int32Array;
michael@0: typedef TypedArray<uint32_t, js::UnwrapUint32Array, JS_GetUint32ArrayData,
michael@0:                    js::GetUint32ArrayLengthAndData, JS_NewUint32Array>
michael@0:         Uint32Array;
michael@0: typedef TypedArray<float, js::UnwrapFloat32Array, JS_GetFloat32ArrayData,
michael@0:                    js::GetFloat32ArrayLengthAndData, JS_NewFloat32Array>
michael@0:         Float32Array;
michael@0: typedef TypedArray<double, js::UnwrapFloat64Array, JS_GetFloat64ArrayData,
michael@0:                    js::GetFloat64ArrayLengthAndData, JS_NewFloat64Array>
michael@0:         Float64Array;
michael@0: typedef TypedArray_base<uint8_t, js::UnwrapArrayBufferView, js::GetArrayBufferViewLengthAndData>
michael@0:         ArrayBufferView;
michael@0: typedef TypedArray<uint8_t, js::UnwrapArrayBuffer, JS_GetArrayBufferData,
michael@0:                    js::GetArrayBufferLengthAndData, JS_NewArrayBuffer>
michael@0:         ArrayBuffer;
michael@0: 
michael@0: // A class for converting an nsTArray to a TypedArray
michael@0: // Note: A TypedArrayCreator must not outlive the nsTArray it was created from.
michael@0: //       So this is best used to pass from things that understand nsTArray to
michael@0: //       things that understand TypedArray, as with Promise::ArgumentToJSValue.
michael@0: template<typename TypedArrayType>
michael@0: class TypedArrayCreator
michael@0: {
michael@0:   typedef nsTArray<typename TypedArrayType::element_type> ArrayType;
michael@0: 
michael@0:   public:
michael@0:     TypedArrayCreator(const ArrayType& aArray)
michael@0:       : mArray(aArray)
michael@0:     {}
michael@0: 
michael@0:     JSObject* Create(JSContext* aCx) const
michael@0:     {
michael@0:       return TypedArrayType::Create(aCx, mArray.Length(), mArray.Elements());
michael@0:     }
michael@0: 
michael@0:   private:
michael@0:     const ArrayType& mArray;
michael@0: };
michael@0: 
michael@0: // A class for rooting an existing TypedArray struct
michael@0: template<typename ArrayType>
michael@0: class MOZ_STACK_CLASS TypedArrayRooter : private JS::CustomAutoRooter
michael@0: {
michael@0: public:
michael@0:   TypedArrayRooter(JSContext* cx,
michael@0:                    ArrayType* aArray MOZ_GUARD_OBJECT_NOTIFIER_PARAM) :
michael@0:     JS::CustomAutoRooter(cx MOZ_GUARD_OBJECT_NOTIFIER_PARAM_TO_PARENT),
michael@0:     mArray(aArray)
michael@0:   {
michael@0:   }
michael@0: 
michael@0:   virtual void trace(JSTracer* trc) MOZ_OVERRIDE
michael@0:   {
michael@0:     mArray->TraceSelf(trc);
michael@0:   }
michael@0: 
michael@0: private:
michael@0:   TypedArrayObjectStorage* const mArray;
michael@0: };
michael@0: 
michael@0: // And a specialization for dealing with nullable typed arrays
michael@0: template<typename Inner> struct Nullable;
michael@0: template<typename ArrayType>
michael@0: class MOZ_STACK_CLASS TypedArrayRooter<Nullable<ArrayType> > :
michael@0:     private JS::CustomAutoRooter
michael@0: {
michael@0: public:
michael@0:   TypedArrayRooter(JSContext* cx,
michael@0:                    Nullable<ArrayType>* aArray MOZ_GUARD_OBJECT_NOTIFIER_PARAM) :
michael@0:     JS::CustomAutoRooter(cx MOZ_GUARD_OBJECT_NOTIFIER_PARAM_TO_PARENT),
michael@0:     mArray(aArray)
michael@0:   {
michael@0:   }
michael@0: 
michael@0:   virtual void trace(JSTracer* trc) MOZ_OVERRIDE
michael@0:   {
michael@0:     if (!mArray->IsNull()) {
michael@0:       mArray->Value().TraceSelf(trc);
michael@0:     }
michael@0:   }
michael@0: 
michael@0: private:
michael@0:   Nullable<ArrayType>* const mArray;
michael@0: };
michael@0: 
michael@0: // Class for easily setting up a rooted typed array object on the stack
michael@0: template<typename ArrayType>
michael@0: class MOZ_STACK_CLASS RootedTypedArray : public ArrayType,
michael@0:                                          private TypedArrayRooter<ArrayType>
michael@0: {
michael@0: public:
michael@0:   RootedTypedArray(JSContext* cx MOZ_GUARD_OBJECT_NOTIFIER_PARAM) :
michael@0:     ArrayType(),
michael@0:     TypedArrayRooter<ArrayType>(cx,
michael@0:                                 MOZ_THIS_IN_INITIALIZER_LIST()
michael@0:                                 MOZ_GUARD_OBJECT_NOTIFIER_PARAM_TO_PARENT)
michael@0:   {
michael@0:   }
michael@0: 
michael@0:   RootedTypedArray(JSContext* cx, JSObject* obj MOZ_GUARD_OBJECT_NOTIFIER_PARAM) :
michael@0:     ArrayType(obj),
michael@0:     TypedArrayRooter<ArrayType>(cx,
michael@0:                                 MOZ_THIS_IN_INITIALIZER_LIST()
michael@0:                                 MOZ_GUARD_OBJECT_NOTIFIER_PARAM_TO_PARENT)
michael@0:   {
michael@0:   }
michael@0: };
michael@0: 
michael@0: } // namespace dom
michael@0: } // namespace mozilla
michael@0: 
michael@0: #endif /* mozilla_dom_TypedArray_h */