RWCompressedIStream< Compressor > Class Template Reference
[Virtual Streams]

Deserializes and decompresses data from an associated std::streambuf. More...

#include <rw/tools/cmpstream.h>

Inherits std::istream.

List of all members.

Public Member Functions
	RWCompressedIStream (std::streambuf *stream_buffer, std::ios_base::openmode mode=std::ios_base::in, rwuint32 block_size=2048U, const Compressor &compressor=Compressor())
	RWCompressedIStream (std::istream &stream, std::ios_base::openmode mode=std::ios_base::in, rwuint32 block_size=2048U, const Compressor &compressor=Compressor())
void	open (std::streambuf *stream_buffer, std::ios_base::openmode mode=std::ios_base::in, rwuint32 block_size=2048U)
void	close ()
bool	is_open () const
const Compressor &	get_compressor () const
RWCompressedStreamBuffer < Compressor > *	rdbuf () const

---

Detailed Description

template<class Compressor>
class RWCompressedIStream< Compressor >

Class RWCompressedIStream deserializes and decompresses data from an associated std::streambuf. The data on that streambuf must have been serialized with its counterpart RWCompressedOStream.

See also:

RWCompressedStreamBuffer

Note:

RWCompressedIStream can be interrogated as to the stream state using member functions good(), bad(), eof(), etc.

Synopsis

 #include <rw/tools/cmpstream.h>
 RWCompressedIStream<Compressor> cstr(std::cin);   // Construct an RWCompressedIStream using cin's streambuf

Persistence

None

Examples

 // for SourcePro Core Tools Module compressed streams
 #include <rw/tools/cmpstream.h>

 // for SourcePro Core Tools Module endian streams
 #include <rw/estream.h>

 // for SourcePro Core Tools Module strings
 #include <rw/cstring.h>

 // for SourcePro Core Snappy compressor
 #include <rw/tools/snappy/RWSnappyCompressor.h>

 // for C++ Standard Library file streams
 #include <fstream>

 int main ()
 {
   // open the file to read from
   std::ifstream input_file ("output.snap", std::ios_base::binary);

   // layer a compressed stream on top of the file
   RWCompressedIStream<RWSnappyCompressor> compressed_stream (input_file);

   // layer an endian stream on top of the compressed stream
   RWeistream endian_stream (compressed_stream);

   //
   // Any data read from the endian stream is read from the file
   // stream, decompressed by the compressed stream, and converted from
   // an endian safe format into binary data by the endian stream.
   //

   RWCString data;

   endian_stream >> data;

   std::cout << data;

   return 0;
 }

Program output:

 aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa

---

Constructor & Destructor Documentation

template<class Compressor>

RWCompressedIStream< Compressor >::RWCompressedIStream	(	std::streambuf *	stream_buffer,
		std::ios_base::openmode	mode = std::ios_base::in,
		rwuint32	block_size = 2048U,
		const Compressor &	compressor = Compressor()
	)			[inline]

Constructor initializes and opens the underlying stream buffer with the provided stream_buffer, mode, block_size, and compressor. If the open fails, failbit is set on this stream.

Note:

The mode is always combined with the appropriate flags to allow the underlying stream buffer to be used for input.

See also:

RWCompressedStreamBuffer::open()

template<class Compressor>

RWCompressedIStream< Compressor >::RWCompressedIStream	(	std::istream &	stream,
		std::ios_base::openmode	mode = std::ios_base::in,
		rwuint32	block_size = 2048U,
		const Compressor &	compressor = Compressor()
	)			[inline]

Constructor initializes and opens the underlying stream buffer with the provided mode, block_size, compressor, and the stream buffer associated with stream. If the open fails, failbit is set on this stream.

Note:

The mode is always combined with the appropriate flags to allow the underlying stream buffer to be used for input.

See also:

RWCompressedStreamBuffer::open()

---

Member Function Documentation

template<class Compressor>

void RWCompressedIStream< Compressor >::close

(

)

[inline]

Closes the underlying stream buffer. If the close fails, failbit is set on this stream. After this method has been called, this stream cannot be used for input until a successfull call to open() has been made.

template<class Compressor>

const Compressor& RWCompressedIStream< Compressor >::get_compressor

(

)

const [inline]

Returns a reference to the underlying stream buffer's compressor.

template<class Compressor>

bool RWCompressedIStream< Compressor >::is_open

(

)

const [inline]

Returns true if the underlying stream buffer is open and is ready for use, otherwise returns false.

template<class Compressor>

void RWCompressedIStream< Compressor >::open	(	std::streambuf *	stream_buffer,
		std::ios_base::openmode	mode = std::ios_base::in,
		rwuint32	block_size = 2048U
	)			[inline]

Opens the underlying stream buffer with the provided stream_buffer, mode, and block_size. If the open fails, failbit is set on this stream.

Note:

The mode is always combined with the appropriate flags to allow the underlying stream buffer to be used for input.

See also:

RWCompressedStreamBuffer::open()

template<class Compressor>

RWCompressedStreamBuffer<Compressor>* RWCompressedIStream< Compressor >::rdbuf

(

)

const [inline]

Returns a pointer to the underlying stream buffer.