grk::DiskCache Class Reference

Secondary disk-based cache for compressed tile data. More...

#include <DiskCache.h>

Public Member Functions
	DiskCache (const std::string &basePath="")
	Create a disk cache in a temporary directory.
	~DiskCache ()
	DiskCache (const DiskCache &)=delete
DiskCache &	operator= (const DiskCache &)=delete
void	store (uint16_t tileIndex, const uint8_t *data, size_t size)
	Store raw bytes to disk for a given tile.
std::optional< std::vector< uint8_t > >	load (uint16_t tileIndex)
	Load raw bytes from disk for a given tile.
bool	contains (uint16_t tileIndex) const
	Check if a tile is stored on disk.
void	clear ()
	Remove all cached entries from disk.
size_t	size () const

Private Member Functions
std::filesystem::path	tilePath (uint16_t tileIndex) const

Private Attributes
std::filesystem::path	cacheDir_
std::unordered_map< uint16_t, size_t >	index_
std::mutex	mutex_

Detailed Description

Secondary disk-based cache for compressed tile data.

When the in-memory CompressedChunkCache evicts an entry, it is spilled here. The disk cache stores each tile's raw byte blob in a separate file under a temporary directory.

Reads use standard file I/O. The directory is cleaned up on destruction.

Constructor & Destructor Documentation

DiskCache() [1/2]

grk::DiskCache::DiskCache ( const std::string & basePath = "" )

inlineexplicit

Create a disk cache in a temporary directory.

Parameters

basePath

optional base directory (default: system temp)

References cacheDir_.

Referenced by DiskCache(), and operator=().

~DiskCache()

grk::DiskCache::~DiskCache ( )

inline

References cacheDir_.

DiskCache() [2/2]

grk::DiskCache::DiskCache ( const DiskCache & )

delete

References DiskCache().

Member Function Documentation

clear()

void grk::DiskCache::clear ( )

inline

Remove all cached entries from disk.

References index_, mutex_, and tilePath().

contains()

bool grk::DiskCache::contains ( uint16_t tileIndex ) const

inline

Check if a tile is stored on disk.

References index_, and mutex_.

load()

std::optional< std::vector< uint8_t > > grk::DiskCache::load ( uint16_t tileIndex )

inline

Load raw bytes from disk for a given tile.

Returns

the bytes if found, or std::nullopt

References index_, mutex_, and tilePath().

operator=()

DiskCache & grk::DiskCache::operator= ( const DiskCache & )

delete

References DiskCache().

size()

size_t grk::DiskCache::size ( ) const

inline

References index_, and mutex_.

Referenced by store().

store()

void grk::DiskCache::store ( uint16_t tileIndex, const uint8_t * data, size_t size )

inline

Store raw bytes to disk for a given tile.

References index_, mutex_, size(), and tilePath().

tilePath()

std::filesystem::path grk::DiskCache::tilePath ( uint16_t tileIndex ) const

inlineprivate

References cacheDir_.

Referenced by clear(), load(), and store().

Member Data Documentation

cacheDir_

std::filesystem::path grk::DiskCache::cacheDir_

private

Referenced by DiskCache(), tilePath(), and ~DiskCache().

index_

std::unordered_map<uint16_t, size_t> grk::DiskCache::index_

private

Referenced by clear(), contains(), load(), size(), and store().

mutex_

std::mutex grk::DiskCache::mutex_

mutableprivate

Referenced by clear(), contains(), load(), size(), and store().

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

• DiskCache.h