gecko-dev/dom/encoding/TextEncoder.h

109 lines
3.0 KiB
C++

/* 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_textencoder_h_
#define mozilla_dom_textencoder_h_
#include "jsapi.h"
#include "mozilla/dom/BindingUtils.h"
#include "mozilla/dom/TextEncoderBinding.h"
#include "mozilla/dom/TypedArray.h"
#include "mozilla/ErrorResult.h"
#include "nsIUnicodeEncoder.h"
#include "nsString.h"
#include "nsCOMPtr.h"
#include "nsCycleCollectionParticipant.h"
namespace mozilla {
namespace dom {
class TextEncoder : public nsISupports, public nsWrapperCache
{
public:
NS_DECL_CYCLE_COLLECTING_ISUPPORTS
NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(TextEncoder)
// The WebIDL constructor.
static already_AddRefed<TextEncoder>
Constructor(nsISupports* aGlobal,
const nsAString& aEncoding,
ErrorResult& aRv)
{
nsRefPtr<TextEncoder> txtEncoder = new TextEncoder(aGlobal);
txtEncoder->Init(aEncoding, aRv);
if (aRv.Failed()) {
return nullptr;
}
return txtEncoder.forget();
}
TextEncoder(nsISupports* aGlobal)
: mGlobal(aGlobal)
{
MOZ_ASSERT(aGlobal);
SetIsDOMBinding();
}
virtual
~TextEncoder()
{}
virtual JSObject*
WrapObject(JSContext* aCx, JSObject* aScope, bool* aTriedToWrap)
{
return TextEncoderBinding::Wrap(aCx, aScope, this, aTriedToWrap);
}
nsISupports*
GetParentObject()
{
return mGlobal;
}
/**
* Return the encoding name.
*
* @param aEncoding, current encoding.
*/
void GetEncoding(nsAString& aEncoding);
/**
* Encodes incoming utf-16 code units/ DOM string to the requested encoding.
*
* @param aCx Javascript context.
* @param aString utf-16 code units to be encoded.
* @param aOptions Streaming option. Initialised by default to false.
* If the streaming option is false, then the encoding
* algorithm state will get reset. If set to true then
* the previous encoding is reused/continued.
* @return JSObject* The Uint8Array wrapped in a JS object.
*/
JSObject* Encode(JSContext* aCx,
const nsAString& aString,
const TextEncodeOptions& aOptions,
ErrorResult& aRv);
private:
nsCString mEncoding;
nsCOMPtr<nsIUnicodeEncoder> mEncoder;
nsCOMPtr<nsISupports> mGlobal;
/**
* Validates provided encoding and throws an exception if invalid encoding.
* If no encoding is provided then mEncoding is default initialised to "utf-8".
*
* @param aEncoding Optional encoding (case insensitive) provided.
* (valid values are "utf-8", "utf-16", "utf-16be")
* Default value is "utf-8" if no encoding is provided.
* @return aRv EncodingError exception else null.
*/
void Init(const nsAString& aEncoding,
ErrorResult& aRv);
};
} // dom
} // mozilla
#endif // mozilla_dom_textencoder_h_