CompressedStreamZstd.h

 
#pragma once
 
#include <Foundation/Basics.h>
#include <Foundation/Containers/DynamicArray.h>
#include <Foundation/IO/Stream.h>
 
#ifdef BUILDSYSTEM_ENABLE_ZSTD_SUPPORT
 
class PL_FOUNDATION_DLL plCompressedStreamReaderZstd : public plStreamReader
{
public:
  plCompressedStreamReaderZstd(); // [tested]
 
  plCompressedStreamReaderZstd(plStreamReader* pInputStream); // [tested]
 
  ~plCompressedStreamReaderZstd();                            // [tested]
 
  void SetInputStream(plStreamReader* pInputStream); // [tested]
 
  virtual plUInt64 ReadBytes(void* pReadBuffer, plUInt64 uiBytesToRead) override; // [tested]
 
private:
  plResult RefillReadCache();
 
  // local declaration to reduce #include dependencies
  struct InBufferImpl
  {
    const void* src;
    size_t size;
    size_t pos;
  };
 
  bool m_bReachedEnd = false;
  plDynamicArray<plUInt8> m_CompressedCache;
  plStreamReader* m_pInputStream = nullptr;
  /*ZSTD_DStream*/ void* m_pZstdDStream = nullptr;
  /*ZSTD_inBuffer*/ InBufferImpl m_InBuffer;
};
 
class PL_FOUNDATION_DLL plCompressedStreamWriterZstd final : public plStreamWriter
{
public:
  enum class Compression
  {
    Fastest = 1,
    Fast = 5,
    Average = 10,
    High = 15,
    Highest = 18,     // officially up to 22, but with 20 I already encountered never-ending compression times inside zstd :(
    Default = Fastest 
  };
 
  plCompressedStreamWriterZstd();
 
  plCompressedStreamWriterZstd(plStreamWriter* pOutputStream, plUInt32 uiMaxNumWorkerThreads, Compression ratio = Compression::Default, plUInt32 uiCompressionCacheSizeKB = 4); // [tested]
 
  ~plCompressedStreamWriterZstd(); // [tested]
 
  void SetOutputStream(plStreamWriter* pOutputStream, plUInt32 uiMaxNumWorkerThreads, Compression ratio = Compression::Default, plUInt32 uiCompressionCacheSizeKB = 4); // [tested]
 
  virtual plResult WriteBytes(const void* pWriteBuffer, plUInt64 uiBytesToWrite) override; // [tested]
 
  plResult FinishCompressedStream(); // [tested]
 
  plUInt64 GetUncompressedSize() const { return m_uiUncompressedSize; } // [tested]
 
  plUInt64 GetCompressedSize() const { return m_uiCompressedSize; } // [tested]
 
  plUInt64 GetWrittenBytes() const { return m_uiWrittenBytes; } // [tested]
 
  virtual plResult Flush() override; // [tested]
 
private:
  plResult FlushWriteCache();
 
  plUInt64 m_uiUncompressedSize = 0;
  plUInt64 m_uiCompressedSize = 0;
  plUInt64 m_uiWrittenBytes = 0;
 
  // local declaration to reduce #include dependencies
  struct OutBufferImpl
  {
    void* dst;
    size_t size;
    size_t pos;
  };
 
  plStreamWriter* m_pOutputStream = nullptr;
  /*ZSTD_CStream*/ void* m_pZstdCStream = nullptr;
  /*ZSTD_outBuffer*/ OutBufferImpl m_OutBuffer;
 
  plDynamicArray<plUInt8> m_CompressedCache;
};
 
#endif // BUILDSYSTEM_ENABLE_ZSTD_SUPPORT