TAO_Notify::Persistent_File_Allocator Class Reference

A class that manages the details of persistent storage. More...

#include <Persistent_File_Allocator.h>

Collaboration diagram for TAO_Notify::Persistent_File_Allocator:

[legend]List of all members.


Public Member Functions
	Persistent_File_Allocator ()
	The constructor.
	~Persistent_File_Allocator ()
	The destructor.
bool	open (const char *filename, const size_t block_size=512)
void	shutdown ()
	Wait for pending I/O and terminate our work thread.
Persistent_Storage_Block *	allocate ()
Persistent_Storage_Block *	allocate_at (size_t block_number)
	Allocate a new Persistent_Storage_Block at a given address.
Persistent_Storage_Block *	allocate_nowrite ()
	Allocate a PSB that is marked to not persist.
void	used (size_t block_number)
	Mark a block as used, removing it from the free list.
void	free (size_t block_number)
	Mark a block number as able to be used again.
size_t	block_size () const
	Access block size.
bool	read (Persistent_Storage_Block *psb)
	Read data into a PSB.
bool	write (Persistent_Storage_Block *psb)
	Write this block to the file,.
size_t	file_size () const
	for information (unit test) only.
Private Member Functions
void	free_block (const size_t block_number)
	Free a previously assigned block.
bool	allocate_block (size_t &block_number)
	Find and allocate a free block.
void	shutdown_thread ()
	Wait for pending I/O to complete and shut our worker thread down safely.
void	run ()
	The worker's execution thread.
Static Private Member Functions
ACE_THR_FUNC_RETURN	thr_func (void *arg)
Private Attributes
ACE_Thread_Manager	thread_manager_
Random_File	pstore_
Bit_Vector	free_blocks_
ACE_Unbounded_Queue< Persistent_Storage_Block * >	block_queue_
ACE_SYNCH_MUTEX	lock_
ACE_SYNCH_MUTEX	free_blocks_lock_
ACE_SYNCH_MUTEX	queue_lock_
bool	terminate_thread_
bool	thread_active_
ACE_SYNCH_CONDITION	wake_up_thread_

Detailed Description

A class that manages the details of persistent storage.

Maintains a free list, write queue, allocations of new blocks, reads, and writes. This class also manages a thread that performs background updating of a Random_File. @todo this is too much for one class to do. It should be refactored. @todo: we shouldn't arbitrarily use a thread.

Constructor & Destructor Documentation

TAO_Notify::Persistent_File_Allocator::Persistent_File_Allocator ( )

The constructor.

TAO_Notify::Persistent_File_Allocator::~Persistent_File_Allocator ( )

The destructor.

Member Function Documentation

Persistent_Storage_Block * TAO_Notify::Persistent_File_Allocator::allocate ( )

Allocate a new Persistent_Storage_Block and initialize it to an unused block of storage.

Persistent_Storage_Block * TAO_Notify::Persistent_File_Allocator::allocate_at ( size_t block_number )

Allocate a new Persistent_Storage_Block at a given address.

bool TAO_Notify::Persistent_File_Allocator::allocate_block ( size_t & block_number ) [private]

Find and allocate a free block.

Persistent_Storage_Block * TAO_Notify::Persistent_File_Allocator::allocate_nowrite ( )

Allocate a PSB that is marked to not persist.

size_t TAO_Notify::Persistent_File_Allocator::block_size ( ) const

Access block size.

size_t TAO_Notify::Persistent_File_Allocator::file_size ( ) const

for information (unit test) only.

void TAO_Notify::Persistent_File_Allocator::free ( size_t block_number )

Mark a block number as able to be used again.

void TAO_Notify::Persistent_File_Allocator::free_block ( const size_t block_number ) [private]

Free a previously assigned block.

bool TAO_Notify::Persistent_File_Allocator::open ( const char * filename,

const size_t block_size = 512

)

bool TAO_Notify::Persistent_File_Allocator::read ( Persistent_Storage_Block * psb )

Read data into a PSB.
Data will come either from the queue of blocks to be written, or it will be read from the file if there are no queued write requests for this block.

void TAO_Notify::Persistent_File_Allocator::run ( ) [private]

The worker's execution thread.

void TAO_Notify::Persistent_File_Allocator::shutdown ( )

Wait for pending I/O and terminate our work thread.

void TAO_Notify::Persistent_File_Allocator::shutdown_thread ( ) [private]

Wait for pending I/O to complete and shut our worker thread down safely.

ACE_THR_FUNC_RETURN TAO_Notify::Persistent_File_Allocator::thr_func ( void * arg ) [static, private]

Used during thread startup to cast us back to ourselves and call the run() method.

void TAO_Notify::Persistent_File_Allocator::used ( size_t block_number )

Mark a block as used, removing it from the free list.

bool TAO_Notify::Persistent_File_Allocator::write ( Persistent_Storage_Block * psb )

Write this block to the file,.
Add the Persistent_Storage_Block to our write queue and let the worker thread handle writing this to the Random_File.