third_party/WebKit/Source/modules/encoding/TextEncoder.cpp

/*
 * Copyright (C) 2013 Google Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions are
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#include "modules/encoding/TextEncoder.h"

#include "bindings/core/v8/ExceptionState.h"
#include "core/dom/ExecutionContext.h"
#include "core/frame/UseCounter.h"
#include "modules/encoding/Encoding.h"
#include "wtf/text/CString.h"
#include "wtf/text/TextEncodingRegistry.h"

namespace blink {

TextEncoder* TextEncoder::create(ExecutionContext* context, const String& utfLabel, ExceptionState& exceptionState)
{
    WTF::TextEncoding encoding(utfLabel.stripWhiteSpace(&Encoding::isASCIIWhiteSpace));
    if (!encoding.isValid()) {
        exceptionState.throwRangeError("The encoding label provided ('" + utfLabel + "') is invalid.");
        return 0;
    }

    String name(encoding.name());
    if (name != "UTF-8" && name != "UTF-16LE" && name != "UTF-16BE") {
        exceptionState.throwRangeError("The encoding provided ('" + utfLabel + "') is not one of 'utf-8', 'utf-16', or 'utf-16be'.");
        return 0;
    }

    if (name == "UTF-16LE" || name == "UTF-16BE")
        UseCounter::count(context, UseCounter::TextEncoderUTF16);

    return new TextEncoder(encoding);
}

TextEncoder::TextEncoder(const WTF::TextEncoding& encoding)
    : m_encoding(encoding)
    , m_codec(newTextCodec(encoding))
{
}

TextEncoder::~TextEncoder()
{
}

String TextEncoder::encoding() const
{
    String name = String(m_encoding.name()).lower();
    ASSERT(name == "utf-8" || name == "utf-16le" || name == "utf-16be");
    return name;
}

DOMUint8Array* TextEncoder::encode(const String& input)
{
    CString result;
    if (input.is8Bit())
        result = m_codec->encode(input.characters8(), input.length(), WTF::QuestionMarksForUnencodables);
    else
        result = m_codec->encode(input.characters16(), input.length(), WTF::QuestionMarksForUnencodables);

    const char* buffer = result.data();
    const unsigned char* unsignedBuffer = reinterpret_cast<const unsigned char*>(buffer);

    return DOMUint8Array::create(unsignedBuffer, result.length());
}

} // namespace blink