gecko/dom/bindings/TypedArray.h

98 lines
3.3 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, typename U,
U* GetData(JSObject*, JSContext*),
uint32_t GetLength(JSObject*, JSContext*)>
struct TypedArray_base {
TypedArray_base(JSContext* cx, JSObject* obj) :
mData(static_cast<T*>(GetData(obj, cx))),
mLength(GetLength(obj, cx)),
mObj(obj)
{}
T* const mData;
const uint32_t mLength;
JSObject* const mObj;
};
template<typename T, typename U,
U* GetData(JSObject*, JSContext*),
uint32_t GetLength(JSObject*, JSContext*),
JSObject* CreateNew(JSContext*, uint32_t)>
struct TypedArray : public TypedArray_base<T,U,GetData,GetLength> {
TypedArray(JSContext* cx, JSObject* obj) :
TypedArray_base<T,U,GetData,GetLength>(cx, obj)
{}
static inline JSObject*
Create(JSContext* cx, uint32_t length, T* data = 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, int8_t, JS_GetInt8ArrayData, JS_GetTypedArrayLength,
JS_NewInt8Array>
Int8Array;
typedef TypedArray<uint8_t, uint8_t, JS_GetUint8ArrayData,
JS_GetTypedArrayLength, JS_NewUint8Array>
Uint8Array;
typedef TypedArray<uint8_t, uint8_t, JS_GetUint8ClampedArrayData,
JS_GetTypedArrayLength, JS_NewUint8Array>
Uint8ClampedArray;
typedef TypedArray<int16_t, int16_t, JS_GetInt16ArrayData,
JS_GetTypedArrayLength, JS_NewInt16Array>
Int16Array;
typedef TypedArray<uint16_t, uint16_t, JS_GetUint16ArrayData,
JS_GetTypedArrayLength, JS_NewUint16Array>
Uint16Array;
typedef TypedArray<int32_t, int32_t, JS_GetInt32ArrayData,
JS_GetTypedArrayLength, JS_NewInt32Array>
Int32Array;
typedef TypedArray<uint32_t, uint32_t, JS_GetUint32ArrayData,
JS_GetTypedArrayLength, JS_NewUint32Array>
Uint32Array;
typedef TypedArray<float, float, JS_GetFloat32ArrayData, JS_GetTypedArrayLength,
JS_NewFloat32Array>
Float32Array;
typedef TypedArray<double, double, JS_GetFloat64ArrayData,
JS_GetTypedArrayLength, JS_NewFloat64Array>
Float64Array;
typedef TypedArray_base<uint8_t, void, JS_GetArrayBufferViewData,
JS_GetArrayBufferViewByteLength>
ArrayBufferView;
typedef TypedArray<uint8_t, uint8_t, JS_GetArrayBufferData,
JS_GetArrayBufferByteLength, JS_NewArrayBuffer>
ArrayBuffer;
} // namespace dom
} // namespace mozilla
#endif /* mozilla_dom_TypedArray_h */