XFILE::CCircularCache Class Reference

#include <CircularCache.h>

Inheritance diagram for XFILE::CCircularCache:

Public Member Functions
	CCircularCache (size_t front, size_t back)
	~CCircularCache () override
int	Open () override
void	Close () override
size_t	GetMaxWriteSize (const size_t &iRequestSize) override
int	WriteToCache (const char *buf, size_t len) override
int	ReadFromCache (char *buf, size_t len) override
int64_t	WaitForData (uint32_t minimum, std::chrono::milliseconds timeout) override
int64_t	Seek (int64_t pos) override
bool	Reset (int64_t pos) override
	Reset cache position.
int64_t	CachedDataEndPosIfSeekTo (int64_t iFilePosition) override
int64_t	CachedDataStartPos () override
int64_t	CachedDataEndPos () override
bool	IsCachedPosition (int64_t iFilePosition) override
CCacheStrategy *	CreateNew () override
Public Member Functions inherited from XFILE::CCacheStrategy
virtual	~CCacheStrategy ()
virtual void	EndOfInput ()
virtual bool	IsEndOfInput ()
virtual void	ClearEndOfInput ()

Protected Attributes
int64_t	m_beg = 0
int64_t	m_end = 0
int64_t	m_cur = 0
uint8_t *	m_buf
size_t	m_size
size_t	m_size_back
CCriticalSection	m_sync
CEvent	m_written
Protected Attributes inherited from XFILE::CCacheStrategy
bool	m_bEndOfInput = false

Additional Inherited Members
Public Attributes inherited from XFILE::CCacheStrategy
CEvent	m_space

Constructor & Destructor Documentation

CCircularCache()

CCircularCache::CCircularCache	(	size_t	front,
		size_t	back )

~CCircularCache()

CCircularCache::~CCircularCache ( )

override

Member Function Documentation

CachedDataEndPos()

int64_t CCircularCache::CachedDataEndPos ( )

overridevirtual

Implements XFILE::CCacheStrategy.

CachedDataEndPosIfSeekTo()

int64_t CCircularCache::CachedDataEndPosIfSeekTo ( int64_t iFilePosition )

overridevirtual

Implements XFILE::CCacheStrategy.

CachedDataStartPos()

int64_t CCircularCache::CachedDataStartPos ( )

overridevirtual

Implements XFILE::CCacheStrategy.

Close()

void CCircularCache::Close ( )

overridevirtual

Implements XFILE::CCacheStrategy.

CreateNew()

CCacheStrategy * CCircularCache::CreateNew ( )

overridevirtual

Implements XFILE::CCacheStrategy.

GetMaxWriteSize()

size_t CCircularCache::GetMaxWriteSize ( const size_t & iRequestSize )

overridevirtual

Implements XFILE::CCacheStrategy.

IsCachedPosition()

bool CCircularCache::IsCachedPosition ( int64_t iFilePosition )

overridevirtual

Implements XFILE::CCacheStrategy.

Open()

int CCircularCache::Open ( )

overridevirtual

Implements XFILE::CCacheStrategy.

ReadFromCache()

int CCircularCache::ReadFromCache ( char * buf, size_t len )

overridevirtual

Reads data from cache. Will only read up till the buffer wrap point. So multiple calls may be needed to empty the whole cache

Implements XFILE::CCacheStrategy.

Reset()

bool CCircularCache::Reset ( int64_t iSourcePosition )

overridevirtual

Reset cache position.

Parameters

iSourcePosition

position to reset to

Returns

Whether a full reset was performed, or not (e.g. only cache swap)

See also

CCacheStrategy

Implements XFILE::CCacheStrategy.

Seek()

int64_t CCircularCache::Seek ( int64_t pos )

overridevirtual

Implements XFILE::CCacheStrategy.

WaitForData()

int64_t CCircularCache::WaitForData ( uint32_t minimum, std::chrono::milliseconds timeout )

overridevirtual

Implements XFILE::CCacheStrategy.

WriteToCache()

int CCircularCache::WriteToCache ( const char * buf, size_t len )

overridevirtual

Function will write to m_buf at m_end % m_size location it will write at maximum m_size, but it will only write as much it can without wrapping around in the buffer

It will always leave m_size_back of the backbuffer intact but if the back buffer is less than that, that space is usable to write.

If back buffer is filled to an larger extent than m_size_back, it will allow it to be overwritten until only m_size_back data remains.

The following always apply:

• m_end <= m_cur <= m_end
• m_end - m_beg <= m_size

Multiple calls may be needed to fill buffer completely.

Implements XFILE::CCacheStrategy.

Member Data Documentation

m_beg

int64_t XFILE::CCircularCache::m_beg = 0

protected

index in file (not buffer) of beginning of valid data

m_buf

uint8_t* XFILE::CCircularCache::m_buf

protected

buffer holding data

m_cur

int64_t XFILE::CCircularCache::m_cur = 0

protected

current reading index in file

m_end

int64_t XFILE::CCircularCache::m_end = 0

protected

index in file (not buffer) of end of valid data

m_size

size_t XFILE::CCircularCache::m_size

protected

size of data buffer used (m_buf)

m_size_back

size_t XFILE::CCircularCache::m_size_back

protected

guaranteed size of back buffer (actual size can be smaller, or larger if front buffer doesn't need it)

m_sync

CCriticalSection XFILE::CCircularCache::m_sync

protected

m_written

CEvent XFILE::CCircularCache::m_written

protected

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

• CircularCache.h
• CircularCache.cpp