chromium/third_party/angle/third_party/rapidjson/src/include/rapidjson/encodings.h

// Tencent is pleased to support the open source community by making RapidJSON available.
// 
// Copyright (C) 2015 THL A29 Limited, a Tencent company, and Milo Yip.
//
// Licensed under the MIT License (the "License"); you may not use this file except
// in compliance with the License. You may obtain a copy of the License at
//
// http://opensource.org/licenses/MIT
//
// Unless required by applicable law or agreed to in writing, software distributed 
// under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR 
// CONDITIONS OF ANY KIND, either express or implied. See the License for the 
// specific language governing permissions and limitations under the License.

#ifndef RAPIDJSON_ENCODINGS_H_
#define RAPIDJSON_ENCODINGS_H_

#include "rapidjson.h"

#if defined(_MSC_VER) && !defined(__clang__)
RAPIDJSON_DIAG_PUSH
RAPIDJSON_DIAG_OFF(4244) // conversion from 'type1' to 'type2', possible loss of data
RAPIDJSON_DIAG_OFF(4702)  // unreachable code
#elif defined(__GNUC__)
RAPIDJSON_DIAG_PUSH
RAPIDJSON_DIAG_OFF()
RAPIDJSON_DIAG_OFF()
#endif

RAPIDJSON_NAMESPACE_BEGIN

///////////////////////////////////////////////////////////////////////////////
// Encoding

/*! \class rapidjson::Encoding
    \brief Concept for encoding of Unicode characters.

\code
concept Encoding {
    typename Ch;    //! Type of character. A "character" is actually a code unit in unicode's definition.

    enum { supportUnicode = 1 }; // or 0 if not supporting unicode

    //! \brief Encode a Unicode codepoint to an output stream.
    //! \param os Output stream.
    //! \param codepoint An unicode codepoint, ranging from 0x0 to 0x10FFFF inclusively.
    template<typename OutputStream>
    static void Encode(OutputStream& os, unsigned codepoint);

    //! \brief Decode a Unicode codepoint from an input stream.
    //! \param is Input stream.
    //! \param codepoint Output of the unicode codepoint.
    //! \return true if a valid codepoint can be decoded from the stream.
    template <typename InputStream>
    static bool Decode(InputStream& is, unsigned* codepoint);

    //! \brief Validate one Unicode codepoint from an encoded stream.
    //! \param is Input stream to obtain codepoint.
    //! \param os Output for copying one codepoint.
    //! \return true if it is valid.
    //! \note This function just validating and copying the codepoint without actually decode it.
    template <typename InputStream, typename OutputStream>
    static bool Validate(InputStream& is, OutputStream& os);

    // The following functions are deal with byte streams.

    //! Take a character from input byte stream, skip BOM if exist.
    template <typename InputByteStream>
    static CharType TakeBOM(InputByteStream& is);

    //! Take a character from input byte stream.
    template <typename InputByteStream>
    static Ch Take(InputByteStream& is);

    //! Put BOM to output byte stream.
    template <typename OutputByteStream>
    static void PutBOM(OutputByteStream& os);

    //! Put a character to output byte stream.
    template <typename OutputByteStream>
    static void Put(OutputByteStream& os, Ch c);
};
\endcode
*/

///////////////////////////////////////////////////////////////////////////////
// UTF8

//! UTF-8 encoding.
/*! http://en.wikipedia.org/wiki/UTF-8
    http://tools.ietf.org/html/rfc3629
    \tparam CharType Code unit for storing 8-bit UTF-8 data. Default is char.
    \note implements Encoding concept
*/
template<typename CharType = char>
struct UTF8 {};

///////////////////////////////////////////////////////////////////////////////
// UTF16

//! UTF-16 encoding.
/*! http://en.wikipedia.org/wiki/UTF-16
    http://tools.ietf.org/html/rfc2781
    \tparam CharType Type for storing 16-bit UTF-16 data. Default is wchar_t. C++11 may use char16_t instead.
    \note implements Encoding concept

    \note For in-memory access, no need to concern endianness. The code units and code points are represented by CPU's endianness.
    For streaming, use UTF16LE and UTF16BE, which handle endianness.
*/
template<typename CharType = wchar_t>
struct UTF16 {};

//! UTF-16 little endian encoding.
template<typename CharType = wchar_t>
struct UTF16LE : UTF16<CharType> {};

//! UTF-16 big endian encoding.
template<typename CharType = wchar_t>
struct UTF16BE : UTF16<CharType> {};

///////////////////////////////////////////////////////////////////////////////
// UTF32

//! UTF-32 encoding. 
/*! http://en.wikipedia.org/wiki/UTF-32
    \tparam CharType Type for storing 32-bit UTF-32 data. Default is unsigned. C++11 may use char32_t instead.
    \note implements Encoding concept

    \note For in-memory access, no need to concern endianness. The code units and code points are represented by CPU's endianness.
    For streaming, use UTF32LE and UTF32BE, which handle endianness.
*/
template<typename CharType = unsigned>
struct UTF32 {};

//! UTF-32 little endian enocoding.
template<typename CharType = unsigned>
struct UTF32LE : UTF32<CharType> {};

//! UTF-32 big endian encoding.
template<typename CharType = unsigned>
struct UTF32BE : UTF32<CharType> {};

///////////////////////////////////////////////////////////////////////////////
// ASCII

//! ASCII encoding.
/*! http://en.wikipedia.org/wiki/ASCII
    \tparam CharType Code unit for storing 7-bit ASCII data. Default is char.
    \note implements Encoding concept
*/
template<typename CharType = char>
struct ASCII {};

///////////////////////////////////////////////////////////////////////////////
// AutoUTF

//! Runtime-specified UTF encoding type of a stream.
enum UTFType {};

//! Dynamically select encoding according to stream's runtime-specified UTF encoding type.
/*! \note This class can be used with AutoUTFInputtStream and AutoUTFOutputStream, which provides GetType().
*/
template<typename CharType>
struct AutoUTF {};

///////////////////////////////////////////////////////////////////////////////
// Transcoder

//! Encoding conversion.
template<typename SourceEncoding, typename TargetEncoding>
struct Transcoder {};

// Forward declaration.
template<typename Stream>
inline void PutUnsafe(Stream& stream, typename Stream::Ch c);

//! Specialization of Transcoder with same source and target encoding.
Transcoder<Encoding, Encoding>;

RAPIDJSON_NAMESPACE_END

#if defined(__GNUC__) || (defined(_MSC_VER) && !defined(__clang__))
RAPIDJSON_DIAG_POP
#endif

#endif // RAPIDJSON_ENCODINGS_H_