gecko/dom/bindings/TypedArray.h

124 lines
3.7 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-*/
/* vim: set ts=2 sw=2 et tw=79: */
/* 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 mozilla_dom_TypedArray_h
#define mozilla_dom_TypedArray_h
#include "jsfriendapi.h"
namespace mozilla {
namespace dom {
/*
* Various typed array classes for argument conversion. We have a base class
* that has a way of initializing a TypedArray from an existing typed array, and
* a subclass of the base class that supports creation of a relevant typed array
* or array buffer object.
*/
template<typename T,
JSObject* UnboxArray(JSContext*, JSObject*, uint32_t*, T**)>
struct TypedArray_base {
TypedArray_base(JSContext* cx, JSObject* obj)
{
mObj = UnboxArray(cx, obj, &mLength, &mData);
}
private:
T* mData;
uint32_t mLength;
JSObject* mObj;
public:
inline bool inited() const {
return !!mObj;
}
inline T *Data() const {
MOZ_ASSERT(inited());
return mData;
}
inline uint32_t Length() const {
MOZ_ASSERT(inited());
return mLength;
}
inline JSObject *Obj() const {
MOZ_ASSERT(inited());
return mObj;
}
};
template<typename T,
T* GetData(JSObject*, JSContext*),
JSObject* UnboxArray(JSContext*, JSObject*, uint32_t*, T**),
JSObject* CreateNew(JSContext*, uint32_t)>
struct TypedArray : public TypedArray_base<T,UnboxArray> {
TypedArray(JSContext* cx, JSObject* obj) :
TypedArray_base<T,UnboxArray>(cx, obj)
{}
static inline JSObject*
Create(JSContext* cx, nsWrapperCache* creator, uint32_t length,
const T* data = NULL) {
JSObject* creatorWrapper;
JSAutoEnterCompartment ac;
if (creator && (creatorWrapper = creator->GetWrapperPreserveColor())) {
if (!ac.enter(cx, creatorWrapper)) {
return NULL;
}
}
JSObject* obj = CreateNew(cx, length);
if (!obj) {
return NULL;
}
if (data) {
T* buf = static_cast<T*>(GetData(obj, cx));
memcpy(buf, data, length*sizeof(T));
}
return obj;
}
};
typedef TypedArray<int8_t, JS_GetInt8ArrayData, JS_GetObjectAsInt8Array,
JS_NewInt8Array>
Int8Array;
typedef TypedArray<uint8_t, JS_GetUint8ArrayData,
JS_GetObjectAsUint8Array, JS_NewUint8Array>
Uint8Array;
typedef TypedArray<uint8_t, JS_GetUint8ClampedArrayData,
JS_GetObjectAsUint8ClampedArray, JS_NewUint8ClampedArray>
Uint8ClampedArray;
typedef TypedArray<int16_t, JS_GetInt16ArrayData,
JS_GetObjectAsInt16Array, JS_NewInt16Array>
Int16Array;
typedef TypedArray<uint16_t, JS_GetUint16ArrayData,
JS_GetObjectAsUint16Array, JS_NewUint16Array>
Uint16Array;
typedef TypedArray<int32_t, JS_GetInt32ArrayData,
JS_GetObjectAsInt32Array, JS_NewInt32Array>
Int32Array;
typedef TypedArray<uint32_t, JS_GetUint32ArrayData,
JS_GetObjectAsUint32Array, JS_NewUint32Array>
Uint32Array;
typedef TypedArray<float, JS_GetFloat32ArrayData,
JS_GetObjectAsFloat32Array, JS_NewFloat32Array>
Float32Array;
typedef TypedArray<double, JS_GetFloat64ArrayData,
JS_GetObjectAsFloat64Array, JS_NewFloat64Array>
Float64Array;
typedef TypedArray_base<uint8_t, JS_GetObjectAsArrayBufferView>
ArrayBufferView;
typedef TypedArray<uint8_t, JS_GetArrayBufferData,
JS_GetObjectAsArrayBuffer, JS_NewArrayBuffer>
ArrayBuffer;
} // namespace dom
} // namespace mozilla
#endif /* mozilla_dom_TypedArray_h */