Class TZLibCompress::TImpl

util/stream/zlib.cpp:189–241

} // namespace

class TZLibCompress::TImpl: public TAdditionalStorage<TImpl>, private TZLibCommon {
    static inline ZLib::StreamType Type(ZLib::StreamType type) {
        if (type == ZLib::Auto) {
            return ZLib::ZLib;
        }

        if (type >= ZLib::Invalid) {
            ythrow TZLibError() << "invalid compression type: " << static_cast<unsigned long>(type);
        }

        return type;
    }

public:
    inline TImpl(const TParams& p)
        : Stream_(p.Out)
    {
        if (deflateInit2(Z(), Min<size_t>(9, p.CompressionLevel), Z_DEFLATED, opts[Type(p.Type)], 8, Z_DEFAULT_STRATEGY)) {
            ythrow TZLibCompressorError() << "can not init inflate engine";
        }

        // Create exactly the same files on all platforms by fixing OS field in the header.
        if (p.Type == ZLib::GZip) {
            GZHeader_ = MakeHolder<gz_header>();
            GZHeader_->os = 3; // UNIX
            deflateSetHeader(Z(), GZHeader_.Get());
        }

        if (p.Dict.size()) {
            if (deflateSetDictionary(Z(), (const Bytef*)p.Dict.data(), p.Dict.size())) {
                ythrow TZLibCompressorError() << "can not set deflate dictionary";
            }
        }

        Z()->next_out = TmpBuf();
        Z()->avail_out = TmpBufLen();
    }

    inline ~TImpl() {
        deflateEnd(Z());
    }

    inline void Write(const void* buf, size_t size) {
        const Bytef* b = (const Bytef*)buf;
        const Bytef* e = b + size;

        Y_DEFER {
            Z()->next_in = nullptr;
            Z()->avail_in = 0;
        };
        do {
            b = WritePart(b, e);
        } while (b < e);
    }

    inline const Bytef* WritePart(const Bytef* b, const Bytef* e) {