Stream buffer. More...

#include <io_buffer.h>

Inheritance diagram for iobuf:

Collaboration diagram for iobuf:

Public Member Functions
	iobuf (uint16 clusterSize)
	Constructor.

virtual	~iobuf ()
	Destructor.

virtual bool	open (FileSpace &file, uint8 om, const VersionContainer &, bool fullCheck=true)
	Open the file if it is one's own file. The flag fullCheck == false switches off excessive checks (for the sake of performance).

bool	del (FileSpace &file)
	Free space allocated for the file.

bool	truncate (FileSpace &file, size_t from)
	Truncate the file. More...

bool	speedOnClose () const
	Is to be ordered while closing.

void	speedOnClose (bool s)
	Set the flag of ordering while closing.

virtual void	free (size_t c)
	Free the cluster.

Public Member Functions inherited from iobuf_Seq
	iobuf_Seq (uint16 clusterSize)
	Constructor.

virtual	~iobuf_Seq ()
	Destructor.

void	Reserve (size_t n, bool addAdditionalSpace=true)
	< Reserve space for a given number of elements. More...

void	Flush ()
	Free the whole memory.

void	HardFlush ()
	Free the unnecessary memory.

void	Adjust ()
	Add an element to the end of the array.

Cluster *	Add ()
	Add a given element to the end of the array.

Cluster *	Add (const Cluster &e)
	Get the number of elements in array.

Cluster &	operator[] (size_t loc) const
	Access by index operator. More...

int	gc ()
	Get the next byte from the buffer.

size_t	getn (void *, size_t)
	Get the next n bytes from the buffer elementwise.

size_t	getln (void *, size_t)
	Get the next n bytes from the buffer by copying the storage area.

int	pc (uint8 c)
	Get the next byte from the buffer but don't shift the pointer to the next one. More...

size_t	putn (const void *, size_t)
	Put the next n bytes to the buffer elementwise.

size_t	putln (const void *, size_t)
	Put the next n bytes to the buffer by copying the storage area.

void	advance ()
	If current buffer exhausted, advance pointer to the next one.

bool	good () const
	Whether the buffer state is correct.

bool	eof () const
	Is the end of file reached?

uint32	state () const
	Get the buffer state.

void	setState (io::state add)
	Add the buffer state.

void	clearState (io::state sub)
	Remove the buffer state.

io::pos	size () const
	Calculate the current file size.

io::pos	tell () const
	Returns the current position in the file.

void	lseek (size_t pos=SYS_MAX_T)
	Set current position in the buffer.

bool	attach (FileSpace &file, bool check=true)
	Attach the file to the buffer with or without checking.

bool	openSys (uint8 om)
	Open the system file.

virtual void	close ()
	Close the file.

virtual void	closeBuff ()
	Close the buffer.

virtual FileSpace *	enterFileSpace (uint8)
	Set FileSpace with given index for writing (create if necessary).

virtual FileSpace *	enterFileSpace (const ClusterReference &, bool)
	Set position for for writing/reading by given ClusterReference. If saveCurr = true, save previous position.

virtual FileSpace *	enterFileSpace (const ClusterReference &, FileSpace *, bool)
	Set position for writing/reading by given FileSpace and ClusterReference. Warning: in this function, ClusterReference.clusterIndex should contain an index in array of cluster indices in FileSpace! If saveCurr = true, save previous position.

virtual FileSpace *	returnToPreviousFileSpace ()
	Set previous FileSpace for writing/reading.

ClusterReference	getCurrentClusterPos ()
	Get current position in the buffer.

FileSpace &	sysFile ()
	Get access to the system file.

FileSpace *	openedFile () const
	Get access to the open file.

virtual size_t	DOSFileLen () const
	The storage data size (of the file on the disk).

virtual const TCHAR *	DOSFileName () const
	Storage name (of file on the disk).

bool	fresh () const
	Is the buffer fresh?

void	fresh (bool f)
	Set the state of buffer freshness.

bool	modified () const
	Is the buffer modified?

void	modified (bool m)
	Set the state of modified buffer.

uint8	mode () const
	Get the buffer mode.

void	mode (uint8 m)
	Set the buffer mode.

bool	IsInMode () const
	Is in the reading mode?

bool	IsOutMode () const
	Is in the writing mode?

bool	IsInOrOutMode () const
	Is in the reading or writing mode?

bool	deleteIfEmpty () const
	Is the empty file to be deleted?

void	deleteIfEmpty (bool s)
	Set the flag of deleting the empty file.

bool	deleteOnClose () const
	Is the file to be deleted while closing the buffer?

void	deleteOnClose (bool s)
	Set the flag of deleting the file while closing the buffer.

void	SetVersionsByStorage ()
	Set the current version to be equal to the storage version.

VERSION	MathVersion () const
	Return the main version (of the mathematical kernel).

VERSION	AppVersion (size_t ind=-1) const
	Return the additional version (of the target application).

const VersionContainer &	GetVersionsContainer () const
	Get the buffer versions.

VERSION	GetStorageVersion ()
	Get the storage version.

VERSION	GetFormatVersion () const
	Get the format version.

void	SetFormatVersion (VERSION version)
	Set the format version.

Protected Attributes
FileSpace	freed
	List of released clusters.

Protected Attributes inherited from iobuf_Seq
uint8 *	base
	Pointer to the beginning of the buffer.

uint8 *	ptr
	Pointer to the next byte.

uint8 *	end
	Pointer to the end of the file.

VERSION	storageVers
	The storage version (must be before 'curFileVers').

VersionContainer	curFileVers
	Version of the current open file (stream).

VERSION	formatVersion
	The format version.

FileSpace	sys
	System file.

PArray< FileSpace >	files
	List of files contained in iobuf_Seq (the first element is the address of 'sys').

FileSpace *	curr
	Current open file (stream).

size_t	part
	Current cluster in the current open file.

uint16	clusterSize
	Cluster size.

uint8	bufferMode
	Buffer mode.

uint8	curFileMode
	Mode of opening the current file.

bool	modifiedFlag
	The buffer has been modified.

bool	freshFlag
	Is the buffer fresh.

Friends
class	tape

Additional Inherited Members
Protected Member Functions inherited from iobuf_Seq
int	underflow ()
	Called when the whole buffer are read, but it is necessary to continue reading.

int	overflow (uint8 ch)
	Called when the buffer is full but it is necessary to continue writing.

virtual int	setup ()=0
	Set the next buffer.

virtual int	flush ()=0
	Flush the buffer.

void	checkEof ()
	Set the end of file if necessary.

size_t	avail () const
	Get the number of unprocessed bytes in the buffer.

size_t	waiting () const
	Get the number of processed bytes in the buffer.

bool	mine (FileSpace &)
	Check if the file is mine.

void	SetVersionsContainer (const VersionContainer &vers)
	Set the version of open file.

VERSION	SetStorageVersion (VERSION)
	Set the storage version.

Detailed Description

Stream buffer.

Stream buffer - the base class.
FileSpace freed - the list of freed clusters. When the file is deleted, all its clusters are moved here. When the modified Catalog is being closed, all the clusters are deleted from 'freed' which physically lie after the last used cluster. After that the contents of 'freed' is written to 'sys'. While writing, when it is necessary to allocate the new cluster, this array is firstly checked for availability of free clusters. Clusters in 'freed' are always ordered by shift from the beginning of the file.

Member Function Documentation

◆ truncate()

bool iobuf::truncate	(	FileSpace &	file,
		size_t	from
	)

Truncate the file.

Detach file from the buffer.

The documentation for this class was generated from the following file:

io_buffer.h

Public Member Functions

Protected Attributes

Friends

Additional Inherited Members

Detailed Description

Member Function Documentation

◆ truncate()