text: // files.h - originally written and placed in the public domain by Wei Dai
  
  /// \file files.h
  /// \brief Classes providing file-based library services
  /// \since Crypto++ 1.0
  
  #ifndef CRYPTOPP_FILES_H
  #define CRYPTOPP_FILES_H
  
  #include "cryptlib.h"
  #include "filters.h"
  #include "argnames.h"
  #include "smartptr.h"
  
  #include <iostream>
  #include <fstream>
  
  NAMESPACE_BEGIN(CryptoPP)
  
  /// \brief Implementation of Store interface
  /// \details file-based implementation of Store interface
  class CRYPTOPP_DLL FileStore : public Store, private FilterPutSpaceHelper, public NotCopyable
  {
  public:
  	/// \brief Exception thrown when file-based error is encountered
  	class Err : public Exception
  	{
  	public:
  		Err(const std::string &s) : Exception(IO_ERROR, s) {}
  	};
  	/// \brief Exception thrown when file-based open error is encountered
  	class OpenErr : public Err {public: OpenErr(const std::string &filename) : Err("FileStore: error opening file for reading: " + filename) {}};
  	/// \brief Exception thrown when file-based read error is encountered
  	class ReadErr : public Err {public: ReadErr() : Err("FileStore: error reading file") {}};
  
  	/// \brief Construct a FileStore
  	FileStore() : m_stream(NULLPTR), m_space(NULLPTR), m_len(0), m_waiting(0) {}
  
  	/// \brief Construct a FileStore
  	/// \param in an existing stream
  	FileStore(std::istream &in) : m_stream(NULLPTR), m_space(NULLPTR), m_len(0), m_waiting(0)
  		{StoreInitialize(MakeParameters(Name::InputStreamPointer(), &in));}
  
  	/// \brief Construct a FileStore
  	/// \param filename the narrow name of the file to open
  	FileStore(const char *filename) : m_stream(NULLPTR), m_space(NULLPTR), m_len(0), m_waiting(0)
  		{StoreInitialize(MakeParameters(Name::InputFileName(), filename ? filename : ""));}
  
  #if defined(CRYPTOPP_UNIX_AVAILABLE) || defined(CRYPTOPP_DOXYGEN_PROCESSING) || _MSC_VER >= 1400
  	/// \brief Construct a FileStore
  	/// \param filename the Unicode name of the file to open
  	/// \details On non-Windows OS, this function assumes that setlocale() has been called.
  	FileStore(const wchar_t *filename)
  		{StoreInitialize(MakeParameters(Name::InputFileNameWide(), filename));}
  #endif
  
  	/// \brief Retrieves the internal stream
  	/// \returns the internal stream pointer
  	std::istream* GetStream() {return m_stream;}
  
  	/// \brief Retrieves the internal stream
  	/// \returns the internal stream pointer
  	const std::istream* GetStream() const {return m_stream;}
  
  	lword MaxRetrievable() const;
  	size_t TransferTo2(BufferedTransformation &target, lword &transferBytes, const std::string &channel=DEFAULT_CHANNEL, bool blocking=true);
  	size_t CopyRangeTo2(BufferedTransformation &target, lword &begin, lword end=LWORD_MAX, const std::string &channel=DEFAULT_CHANNEL, bool blocking=true) const;
  	lword Skip(lword skipMax=ULONG_MAX);
  
  private:
  	void StoreInitialize(const NameValuePairs &parameters);
  
  	member_ptr<std::ifstream> m_file;
  	std::istream *m_stream;
  	byte *m_space;
  	size_t m_len;
  	bool m_waiting;
  };
  
  /// \brief Implementation of Store interface
  /// \details file-based implementation of Store interface
  class CRYPTOPP_DLL FileSource : public SourceTemplate<FileStore>
  {
  public:
  	typedef FileStore::Err Err;
  	typedef FileStore::OpenErr OpenErr;
  	typedef FileStore::ReadErr ReadErr;
  
  	/// \brief Construct a FileSource
  	FileSource(BufferedTransformation *attachment = NULLPTR)
  		: SourceTemplate<FileStore>(attachment) {}
  
  	/// \brief Construct a FileSource
  	/// \param in an existing stream
  	/// \param pumpAll flag indicating if source data should be pumped to its attached transformation
  	/// \param attachment an optional attached transformation
  	FileSource(std::istream &in, bool pumpAll, BufferedTransformation *attachment = NULLPTR)
  		: SourceTemplate<FileStore>(attachment) {SourceInitialize(pumpAll, MakeParameters(Name::InputStreamPointer(), &in));}
  
  	/// \brief Construct a FileSource
  	/// \param filename the narrow name of the file to open
  	/// \param pumpAll flag indicating if source data should be pumped to its attached transformation
  	/// \param attachment an optional attached transformation
  	/// \param binary flag indicating if the file is binary
  	FileSource(const char *filename, bool pumpAll, BufferedTransformation *attachment = NULLPTR, bool binary=true)
  		: SourceTemplate<FileStore>(attachment) {SourceInitialize(pumpAll, MakeParameters(Name::InputFileName(), filename)(Name::InputBinaryMode(), binary));}
  
  #if defined(CRYPTOPP_UNIX_AVAILABLE) || defined(CRYPTOPP_DOXYGEN_PROCESSING) || _MSC_VER >= 1400
  	/// \brief Construct a FileSource
  	/// \param filename the Unicode name of the file to open
  	/// \param pumpAll flag indicating if source data should be pumped to its attached transformation
  	/// \param attachment an optional attached transformation
  	/// \param binary flag indicating if the file is binary
  	/// \details On non-Windows OS, this function assumes that setlocale() has been called.
  	FileSource(const wchar_t *filename, bool pumpAll, BufferedTransformation *attachment = NULLPTR, bool binary=true)
  		: SourceTemplate<FileStore>(attachment) {SourceInitialize(pumpAll, MakeParameters(Name::InputFileNameWide(), filename)(Name::InputBinaryMode(), binary));}
  #endif
  
  	/// \brief Retrieves the internal stream
  	/// \returns the internal stream pointer
  	std::istream* GetStream() {return m_store.GetStream();}
  };
  
  /// \brief Implementation of Store interface
  /// \details file-based implementation of Sink interface
  class CRYPTOPP_DLL FileSink : public Sink, public NotCopyable
  {
  public:
  	/// \brief Exception thrown when file-based error is encountered
  	class Err : public Exception
  	{
  	public:
  		Err(const std::string &s) : Exception(IO_ERROR, s) {}
  	};
  	/// \brief Exception thrown when file-based open error is encountered
  	class OpenErr : public Err {public: OpenErr(const std::string &filename) : Err("FileSink: error opening file for writing: " + filename) {}};
  	/// \brief Exception thrown when file-based write error is encountered
  	class WriteErr : public Err {public: WriteErr() : Err("FileSink: error writing file") {}};
  
  	/// \brief Construct a FileSink
  	FileSink() : m_stream(NULLPTR) {}
  
  	/// \brief Construct a FileSink
  	/// \param out an existing stream
  	FileSink(std::ostream &out)
  		{IsolatedInitialize(MakeParameters(Name::OutputStreamPointer(), &out));}
  
  	/// \brief Construct a FileSink
  	/// \param filename the narrow name of the file to open
  	/// \param binary flag indicating if the file is binary
  	FileSink(const char *filename, bool binary=true)
  		{IsolatedInitialize(MakeParameters(Name::OutputFileName(), filename)(Name::OutputBinaryMode(), binary));}
  
  #if defined(CRYPTOPP_UNIX_AVAILABLE) || _MSC_VER >= 1400
  	/// \brief Construct a FileSink
  	/// \param filename the Unicode name of the file to open
  	/// \details On non-Windows OS, this function assumes that setlocale() has been called.
  	FileSink(const wchar_t *filename, bool binary=true)
  		{IsolatedInitialize(MakeParameters(Name::OutputFileNameWide(), filename)(Name::OutputBinaryMode(), binary));}
  #endif
  
  	/// \brief Retrieves the internal stream
  	/// \returns the internal stream pointer
  	std::ostream* GetStream() {return m_stream;}
  
  	void IsolatedInitialize(const NameValuePairs &parameters);
  	size_t Put2(const byte *inString, size_t length, int messageEnd, bool blocking);
  	bool IsolatedFlush(bool hardFlush, bool blocking);
  
  private:
  	member_ptr<std::ofstream> m_file;
  	std::ostream *m_stream;
  };
  
  NAMESPACE_END
  
  #endif
  