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// Copyright (c) 2013, Kenton Varda <temporal@gmail.com>
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this
//    list of conditions and the following disclaimer.
// 2. Redistributions in binary form must reproduce the above copyright notice,
//    this list of conditions and the following disclaimer in the documentation
//    and/or other materials provided with the distribution.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
// ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
// (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
// LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
// ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

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#ifndef CAPNP_SERIALIZE_SNAPPY_H_
#define CAPNP_SERIALIZE_SNAPPY_H_
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#include "serialize.h"
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#include "serialize-packed.h"
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namespace capnp {
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constexpr size_t SNAPPY_BUFFER_SIZE = 65536;
constexpr size_t SNAPPY_COMPRESSED_BUFFER_SIZE = 76490;

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class SnappyInputStream: public kj::BufferedInputStream {
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public:
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  explicit SnappyInputStream(BufferedInputStream& inner, kj::ArrayPtr<byte> buffer = nullptr);
  KJ_DISALLOW_COPY(SnappyInputStream);
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  ~SnappyInputStream() noexcept(false);
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  // implements BufferedInputStream ----------------------------------
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  kj::ArrayPtr<const byte> tryGetReadBuffer() override;
  size_t tryRead(void* buffer, size_t minBytes, size_t maxBytes) override;
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  void skip(size_t bytes) override;
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private:
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  class InputStreamSnappySource;

  BufferedInputStream& inner;
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  kj::Array<byte> ownedBuffer;
  kj::ArrayPtr<byte> buffer;
  kj::ArrayPtr<byte> bufferAvailable;
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  bool refill();
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};

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class SnappyOutputStream: public kj::BufferedOutputStream {
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public:
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  explicit SnappyOutputStream(OutputStream& inner,
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                              kj::ArrayPtr<byte> buffer = nullptr,
                              kj::ArrayPtr<byte> compressedBuffer = nullptr);
  KJ_DISALLOW_COPY(SnappyOutputStream);
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  ~SnappyOutputStream() noexcept(false);
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  void flush();
  // Force the stream to write any remaining bytes in its buffer to the inner stream.  This will
  // hurt compression, of course, by forcing the current block to end prematurely.

  // implements BufferedOutputStream ---------------------------------
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  kj::ArrayPtr<byte> getWriteBuffer() override;
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  void write(const void* buffer, size_t size) override;

private:
  OutputStream& inner;
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  kj::Array<byte> ownedBuffer;
  kj::ArrayPtr<byte> buffer;
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  byte* bufferPos;
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  kj::Array<byte> ownedCompressedBuffer;
  kj::ArrayPtr<byte> compressedBuffer;
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  kj::UnwindDetector unwindDetector;
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};

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class SnappyPackedMessageReader: private SnappyInputStream, public PackedMessageReader {
public:
  SnappyPackedMessageReader(
      BufferedInputStream& inputStream, ReaderOptions options = ReaderOptions(),
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      kj::ArrayPtr<word> scratchSpace = nullptr, kj::ArrayPtr<byte> buffer = nullptr);
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  ~SnappyPackedMessageReader() noexcept(false);
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};
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void writeSnappyPackedMessage(kj::OutputStream& output, MessageBuilder& builder,
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                              kj::ArrayPtr<byte> buffer = nullptr,
                              kj::ArrayPtr<byte> compressedBuffer = nullptr);
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void writeSnappyPackedMessage(kj::OutputStream& output,
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                              kj::ArrayPtr<const kj::ArrayPtr<const word>> segments,
                              kj::ArrayPtr<byte> buffer = nullptr,
                              kj::ArrayPtr<byte> compressedBuffer = nullptr);
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// =======================================================================================
// inline stuff

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inline void writeSnappyPackedMessage(kj::OutputStream& output, MessageBuilder& builder,
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                                     kj::ArrayPtr<byte> buffer,
                                     kj::ArrayPtr<byte> compressedBuffer) {
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  writeSnappyPackedMessage(output, builder.getSegmentsForOutput(), buffer, compressedBuffer);
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}

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}  // namespace capnp
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#endif  // CAPNP_SERIALIZE_SNAPPY_H_