text: //
  // FIFOBufferStream.h
  //
  // $Id: //poco/1.4/Foundation/include/Poco/FIFOBufferStream.h#1 $
  //
  // Library: Foundation
  // Package: Streams
  // Module:  FIFOBufferStream
  //
  // Definition of the FIFOBufferStream class.
  //
  // Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
  // and Contributors.
  //
  // 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.
  //
  
  
  #ifndef Foundation_FIFOBufferStream_INCLUDED
  #define Foundation_FIFOBufferStream_INCLUDED
  
  
  #include "Poco/Foundation.h"
  #include "Poco/FIFOBuffer.h"
  #include "Poco/BufferedBidirectionalStreamBuf.h"
  #include <istream>
  #include <ostream>
  
  
  namespace Poco {
  
  
  class Foundation_API FIFOBufferStreamBuf: public BufferedBidirectionalStreamBuf
  	/// This is the streambuf class used for reading from and writing to a FIFOBuffer.
  	/// FIFOBuffer is enabled for emtpy/non-empty/full state transitions notifications.
  {
  public:
  	
  	FIFOBufferStreamBuf();
  		/// Creates a FIFOBufferStreamBuf.
  
  	explicit FIFOBufferStreamBuf(FIFOBuffer& fifoBuffer);
  		/// Creates a FIFOBufferStreamBuf and assigns the given buffer to it.
  
  	explicit FIFOBufferStreamBuf(char* pBuffer, std::size_t length);
  		/// Creates a FIFOBufferStreamBuf and assigns the given buffer to it.
  
  	explicit FIFOBufferStreamBuf(const char* pBuffer, std::size_t length);
  		/// Creates a FIFOBufferStreamBuf and assigns the given buffer to it.
  
  	explicit FIFOBufferStreamBuf(std::size_t length);
  		/// Creates a FIFOBufferStreamBuf of the given length.
  
  	~FIFOBufferStreamBuf();
  		/// Destroys the FIFOBufferStreamBuf.
  
  	FIFOBuffer& fifoBuffer();
  		/// Returns the underlying FIFO buffer reference.
  
  protected:
  	int readFromDevice(char* buffer, std::streamsize length);
  	int writeToDevice(const char* buffer, std::streamsize length);
  
  private:
  	enum 
  	{
  		STREAM_BUFFER_SIZE = 1024
  	};
  
  	FIFOBuffer* _pFIFOBuffer;
  	FIFOBuffer& _fifoBuffer;
  };
  
  
  class Foundation_API FIFOIOS: public virtual std::ios
  	/// The base class for FIFOBufferInputStream and
  	/// FIFOBufferStream.
  	///
  	/// This class is needed to ensure the correct initialization
  	/// order of the stream buffer and base classes.
  {
  public:
  	explicit FIFOIOS(FIFOBuffer& buffer);
  		/// Creates a FIFOIOS and assigns the given buffer to it.
  
  	explicit FIFOIOS(char* pBuffer, std::size_t length);
  		/// Creates a FIFOIOS and assigns the given buffer to it.
  
  	explicit FIFOIOS(const char* pBuffer, std::size_t length);
  		/// Creates a FIFOIOS and assigns the given buffer to it.
  
  	explicit FIFOIOS(std::size_t length);
  		/// Creates a FIFOIOS of the given length.
  		
  	~FIFOIOS();
  		/// Destroys the FIFOIOS.
  		///
  		/// Flushes the buffer.
  		
  	FIFOBufferStreamBuf* rdbuf();
  		/// Returns a pointer to the internal FIFOBufferStreamBuf.
  		
  	void close();
  		/// Flushes the stream.
  
  protected:
  	FIFOBufferStreamBuf _buf;
  };
  
  
  class Foundation_API FIFOBufferStream: public FIFOIOS, public std::iostream
  	/// An output stream for writing to a FIFO.
  {
  public:
  	Poco::BasicEvent<bool>& readable;
  	Poco::BasicEvent<bool>& writable;
  
  	explicit FIFOBufferStream(FIFOBuffer& buffer);
  		/// Creates the FIFOBufferStream with supplied buffer as initial value.
  
  	explicit FIFOBufferStream(char* pBuffer, std::size_t length);
  		/// Creates a FIFOBufferStream and assigns the given buffer to it.
  
  	explicit FIFOBufferStream(const char* pBuffer, std::size_t length);
  		/// Creates a FIFOBufferStream and assigns the given buffer to it.
  
  	explicit FIFOBufferStream(std::size_t length);
  		/// Creates a FIFOBufferStream of the given length.
  
  	~FIFOBufferStream();
  		/// Destroys the FIFOBufferStream.
  		///
  		/// Flushes the buffer.
  
  private:
  	FIFOBufferStream();
  	FIFOBufferStream(const FIFOBufferStream& other);
  	FIFOBufferStream& operator =(const FIFOBufferStream& other);
  };
  
  
  ///
  /// inlines
  ///
  
  
  inline FIFOBuffer& FIFOBufferStreamBuf::fifoBuffer()
  {
  	return _fifoBuffer;
  }
  
  
  } // namespace Poco
  
  
  #endif // Foundation_FIFOBufferStream_INCLUDED
  