zipios::DeflateOutputStreambuf Class Reference

DeflateOutputStreambuf is an output stream filter, that deflates the data that is written to it before it passes it on to the output stream it is attached to. More...

#include <deflateoutputstreambuf.h>

Inheritance diagram for zipios::DeflateOutputStreambuf:

List of all members.

Public Member Functions
bool	closeStream ()
	DeflateOutputStreambuf (streambuf *outbuf, bool user_init=false, bool del_outbuf=false)
	DeflateOutputStreambuf constructor.
uint32	getCount () const
	Returns the number of bytes written to the streambuf, that has been processed from the input buffer by the compressor.
uint32	getCrc32 () const
	Returns the CRC32 for the current stream.
bool	init (int comp_level=6)
virtual	~DeflateOutputStreambuf ()
	Destructor.
Protected Member Functions
void	endDeflation ()
	Flushes the remaining data in the zlib buffers, after which the only possible operations are deflateEnd() or deflateReset().
bool	flushOutvec ()
	Flushes _outvec and updates _zs.next_out and _zs.avail_out.
virtual int	overflow (int c=EOF)
virtual int	sync ()
Protected Attributes
uint32	_crc32
vector< char >	_invec
const int	_invecsize
vector< char >	_outvec
const int	_outvecsize
uint32	_overflown_bytes

Detailed Description

DeflateOutputStreambuf is an output stream filter, that deflates the data that is written to it before it passes it on to the output stream it is attached to.

Deflation/Inflation is a compression/decompression method used in gzip and zip. The zlib library is used to perform the actual deflation, this class only wraps the functionality in an output stream filter.

Definition at line 25 of file deflateoutputstreambuf.h.

Constructor & Destructor Documentation

zipios::DeflateOutputStreambuf::DeflateOutputStreambuf	(	streambuf *	outbuf,
		bool	user_init = `false`,
		bool	del_outbuf = `false`
	)			`[explicit]`

DeflateOutputStreambuf constructor.

Parameters:

	outbuf	the streambuf to use for output.
	user_init	If false user must invoke init() before writing any data. (ZipOutputStreambuf needs to do this)
	del_outbuf	if true is specified outbuf will be deleted, when the DeflateOutputStreambuf is destructed.

Definition at line 18 of file deflateoutputstreambuf.cpp.

References init().

zipios::DeflateOutputStreambuf::~DeflateOutputStreambuf ( ) [virtual]

Destructor.

Definition at line 43 of file deflateoutputstreambuf.cpp.

References closeStream().

Member Function Documentation

bool zipios::DeflateOutputStreambuf::closeStream ( )

Definition at line 88 of file deflateoutputstreambuf.cpp.

References endDeflation().

Referenced by zipios::ZipOutputStreambuf::closeEntry(), zipios::GZIPOutputStreambuf::finish(), and ~DeflateOutputStreambuf().

void zipios::DeflateOutputStreambuf::endDeflation ( ) [protected]

Flushes the remaining data in the zlib buffers, after which the only possible operations are deflateEnd() or deflateReset().

Definition at line 173 of file deflateoutputstreambuf.cpp.

References _outvec, _outvecsize, flushOutvec(), and overflow().

Referenced by closeStream(), and init().

bool zipios::DeflateOutputStreambuf::flushOutvec ( ) [protected]

Flushes _outvec and updates _zs.next_out and _zs.avail_out.

Definition at line 162 of file deflateoutputstreambuf.cpp.

References zipios::FilterOutputStreambuf::_outbuf, _outvec, and _outvecsize.

Referenced by endDeflation(), and overflow().

uint32 zipios::DeflateOutputStreambuf::getCount ( ) const [inline]

Returns the number of bytes written to the streambuf, that has been processed from the input buffer by the compressor.

After closeStream() has been called this number is the total number of bytes written to the stream.

Definition at line 55 of file deflateoutputstreambuf.h.

Referenced by zipios::ZipOutputStreambuf::updateEntryHeaderInfo().

uint32 zipios::DeflateOutputStreambuf::getCrc32 ( ) const [inline]

Returns the CRC32 for the current stream.

The returned value is the CRC for the data that has been compressed already (due to a call to overflow()). As DeflateOutputStreambuf may buffer an arbitrary amount of bytes until closeStream() has been invoked, the returned value is not very useful before closeStream() has been called.

Definition at line 49 of file deflateoutputstreambuf.h.

Referenced by zipios::ZipOutputStreambuf::updateEntryHeaderInfo().

bool zipios::DeflateOutputStreambuf::init ( int comp_level = 6 )

Definition at line 51 of file deflateoutputstreambuf.cpp.

References _crc32, _invec, _invecsize, _outvec, _outvecsize, _overflown_bytes, and endDeflation().

Referenced by DeflateOutputStreambuf(), and zipios::ZipOutputStreambuf::putNextEntry().

int zipios::DeflateOutputStreambuf::overflow ( int c = EOF ) [protected, virtual]

Reimplemented in zipios::GZIPOutputStreambuf, and zipios::ZipOutputStreambuf.

Definition at line 109 of file deflateoutputstreambuf.cpp.

References _crc32, _invec, _invecsize, _outvec, _outvecsize, _overflown_bytes, flushOutvec(), and zipios::OutputStringStream::str().

Referenced by endDeflation().

int zipios::DeflateOutputStreambuf::sync ( ) [protected, virtual]