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c4_Strategy Class Reference

#include <mk4.h>

Inheritance diagram for c4_Strategy:

Inheritance graph

List of all members.

Detailed Description

A strategy encapsulates code dealing with the I/O system interface.

Definition at line 806 of file mk4.h.


Public Member Functions
	c4_Strategy ()
virtual void	DataCommit (t4_i32)
virtual int	DataRead (t4_i32, void *, int)
virtual void	DataWrite (t4_i32, const void *, int)
t4_i32	EndOfData (t4_i32=-1)
virtual t4_i32	FileSize ()
virtual t4_i32	FreshGeneration ()
virtual bool	IsValid () const
virtual void	ResetFileMapping ()
void	SetBase (t4_i32)
virtual	~c4_Strategy ()
Public Attributes
t4_i32	_baseOffset
bool	_bytesFlipped
t4_i32	_dataSize
int	_failure
const t4_byte *	_mapStart
t4_i32	_rootLen
t4_i32	_rootPos

Constructor & Destructor Documentation

c4_Strategy::c4_Strategy ( )

Definition at line 606 of file viewx.cpp.

c4_Strategy::~c4_Strategy ( ) [virtual]

Definition at line 609 of file viewx.cpp.

Member Function Documentation

void c4_Strategy::DataCommit ( t4_i32 ) [virtual]

Flush and truncate file.

Reimplemented in c4_FileStrategy.

Definition at line 632 of file viewx.cpp.

int c4_Strategy::DataRead	(	t4_i32	,
		void *	,
		int
	)			`[virtual]`

Read a number of bytes.

Reimplemented in c4_FileStrategy, and c4_StreamStrategy.

Definition at line 614 of file viewx.cpp.

void c4_Strategy::DataWrite	(	t4_i32	,
		const void *	,
		int
	)			`[virtual]`

Write a number of bytes, return true if successful.

Reimplemented in c4_FileStrategy, and c4_StreamStrategy.

Definition at line 627 of file viewx.cpp.

t4_i32 c4_Strategy::EndOfData ( t4_i32 end_ = -1 )

Scan datafile head/tail markers, return logical end of data.

Definition at line 666 of file viewx.cpp.

t4_i32 c4_Strategy::FileSize ( ) [virtual]

Report total size of the datafile.

Reimplemented in c4_FileStrategy, and c4_StreamStrategy.

Definition at line 638 of file viewx.cpp.

t4_i32 c4_Strategy::FreshGeneration ( ) [virtual]

Return a value to use as fresh generation counter.

Reimplemented in c4_FileStrategy.

Definition at line 643 of file viewx.cpp.

virtual bool c4_Strategy::IsValid ( ) const [virtual]

Reimplemented in c4_FileStrategy, and c4_StreamStrategy.

void c4_Strategy::ResetFileMapping ( ) [virtual]

Override to support memory-mapped files.

Reimplemented in c4_FileStrategy.

Definition at line 635 of file viewx.cpp.

void c4_Strategy::SetBase ( t4_i32 base_ )

Define the base offset where data is stored.

Definition at line 648 of file viewx.cpp.

Member Data Documentation

t4_i32 c4_Strategy::_baseOffset

All file positions are relative to this offset.

Definition at line 832 of file mk4.h.

bool c4_Strategy::_bytesFlipped

True if the storage format is not native (default is false).

Definition at line 824 of file mk4.h.

t4_i32 c4_Strategy::_dataSize

Number of bytes filled with active data.

Definition at line 830 of file mk4.h.

int c4_Strategy::_failure

Error code of last failed I/O operation, zero if I/O was ok.

Definition at line 826 of file mk4.h.

const t4_byte* c4_Strategy::_mapStart

First byte in file mapping, zero if not active.

Definition at line 828 of file mk4.h.

t4_i32 c4_Strategy::_rootLen

The size of the root column.

Definition at line 836 of file mk4.h.

t4_i32 c4_Strategy::_rootPos

The root position of the shallow tree walks.

Definition at line 834 of file mk4.h.

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