Decoder.h

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/*
 * Original work Copyright 2009 - 2010 Kevin Ackley (kackley@gwi.net)
 * Modified work Copyright 2018 - 2020 Andy Maloney <asmaloney@gmail.com>
 *
 * Permission is hereby granted, free of charge, to any person or organization
 * obtaining a copy of the software and accompanying documentation covered by
 * this license (the "Software") to use, reproduce, display, distribute,
 * execute, and transmit the Software, and to prepare derivative works of the
 * Software, and to permit third-parties to whom the Software is furnished to
 * do so, all subject to the following:
 *
 * The copyright notices in the Software and this entire statement, including
 * the above license grant, this restriction and the following disclaimer,
 * must be included in all copies of the Software, in whole or in part, and
 * all derivative works of the Software, unless such copies or derivative
 * works are solely in the form of machine-executable object code generated by
 * a source language processor.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE, TITLE AND NON-INFRINGEMENT. IN NO EVENT
 * SHALL THE COPYRIGHT HOLDERS OR ANYONE DISTRIBUTING THE SOFTWARE BE LIABLE
 * FOR ANY DAMAGES OR OTHER LIABILITY, WHETHER IN CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 */
 
#pragma once
 
#include "Common.h"
 
namespace e57
{
   class Decoder
   {
   public:
      static std::shared_ptr<Decoder> DecoderFactory( unsigned bytestreamNumber,
                                                      const CompressedVectorNodeImpl *cVector,
                                                      std::vector<SourceDestBuffer> &dbufs, const ustring &codecPath );
      Decoder() = delete;
      virtual ~Decoder() = default;
 
      virtual void destBufferSetNew( std::vector<SourceDestBuffer> &dbufs ) = 0;
      virtual uint64_t totalRecordsCompleted() = 0;
      virtual size_t inputProcess( const char *source, const size_t count ) = 0;
      virtual void stateReset() = 0;
      unsigned bytestreamNumber() const
      {
         return bytestreamNumber_;
      }
#ifdef E57_DEBUG
      virtual void dump( int indent = 0, std::ostream &os = std::cout ) = 0;
#endif
 
   protected:
      Decoder( unsigned bytestreamNumber );
 
      unsigned int bytestreamNumber_;
   };
 
   class BitpackDecoder : public Decoder
   {
   public:
      void destBufferSetNew( std::vector<SourceDestBuffer> &dbufs ) override;
 
      uint64_t totalRecordsCompleted() override
      {
         return ( currentRecordIndex_ );
      }
 
      size_t inputProcess( const char *source, const size_t availableByteCount ) override;
      virtual size_t inputProcessAligned( const char *inbuf, const size_t firstBit, const size_t endBit ) = 0;
 
      void stateReset() override;
 
#ifdef E57_DEBUG
      void dump( int indent = 0, std::ostream &os = std::cout ) override;
#endif
   protected:
      BitpackDecoder( unsigned bytestreamNumber, SourceDestBuffer &dbuf, unsigned alignmentSize,
                      uint64_t maxRecordCount );
 
      void inBufferShiftDown();
 
      uint64_t currentRecordIndex_ = 0;
      uint64_t maxRecordCount_ = 0;
 
      std::shared_ptr<SourceDestBufferImpl> destBuffer_;
 
      std::vector<char> inBuffer_;
      size_t inBufferFirstBit_ = 0;
      size_t inBufferEndByte_ = 0;
      unsigned int inBufferAlignmentSize_;
      unsigned int bitsPerWord_;
      unsigned int bytesPerWord_;
   };
 
   class BitpackFloatDecoder : public BitpackDecoder
   {
   public:
      BitpackFloatDecoder( unsigned bytestreamNumber, SourceDestBuffer &dbuf, FloatPrecision precision,
                           uint64_t maxRecordCount );
 
      size_t inputProcessAligned( const char *inbuf, const size_t firstBit, const size_t endBit ) override;
 
#ifdef E57_DEBUG
      void dump( int indent = 0, std::ostream &os = std::cout ) override;
#endif
   protected:
      FloatPrecision precision_ = E57_SINGLE;
   };
 
   class BitpackStringDecoder : public BitpackDecoder
   {
   public:
      BitpackStringDecoder( unsigned bytestreamNumber, SourceDestBuffer &dbuf, uint64_t maxRecordCount );
 
      size_t inputProcessAligned( const char *inbuf, const size_t firstBit, const size_t endBit ) override;
 
#ifdef E57_DEBUG
      void dump( int indent = 0, std::ostream &os = std::cout ) override;
#endif
   protected:
      bool readingPrefix_ = true;
      int prefixLength_ = 1;
      uint8_t prefixBytes_[8] = {};
      int nBytesPrefixRead_ = 0;
      uint64_t stringLength_ = 0;
      ustring currentString_;
      uint64_t nBytesStringRead_ = 0;
   };
 
   template <typename RegisterT> class BitpackIntegerDecoder : public BitpackDecoder
   {
   public:
      BitpackIntegerDecoder( bool isScaledInteger, unsigned bytestreamNumber, SourceDestBuffer &dbuf, int64_t minimum,
                             int64_t maximum, double scale, double offset, uint64_t maxRecordCount );
 
      size_t inputProcessAligned( const char *inbuf, const size_t firstBit, const size_t endBit ) override;
 
#ifdef E57_DEBUG
      void dump( int indent = 0, std::ostream &os = std::cout ) override;
#endif
   protected:
      bool isScaledInteger_;
      int64_t minimum_;
      int64_t maximum_;
      double scale_;
      double offset_;
      unsigned bitsPerRecord_;
      RegisterT destBitMask_;
   };
 
   class ConstantIntegerDecoder : public Decoder
   {
   public:
      ConstantIntegerDecoder( bool isScaledInteger, unsigned bytestreamNumber, SourceDestBuffer &dbuf, int64_t minimum,
                              double scale, double offset, uint64_t maxRecordCount );
      void destBufferSetNew( std::vector<SourceDestBuffer> &dbufs ) override;
      uint64_t totalRecordsCompleted() override
      {
         return currentRecordIndex_;
      }
      size_t inputProcess( const char *source, const size_t availableByteCount ) override;
      void stateReset() override;
#ifdef E57_DEBUG
      void dump( int indent = 0, std::ostream &os = std::cout ) override;
#endif
   protected:
      uint64_t currentRecordIndex_ = 0;
      uint64_t maxRecordCount_;
 
      std::shared_ptr<SourceDestBufferImpl> destBuffer_;
 
      bool isScaledInteger_;
      int64_t minimum_;
      double scale_;
      double offset_;
   };
}