TAO_Persistent_Context_Index Class Reference

This class facilitates implementation of Persistent Naming Service. It keeps track, centrally, of several pieces of info for each Persistent Naming Context, allowing to perform the initialization necessary for each Naming Context to restore the state of the Naming Service from persistent storage on server start-up. More...

#include <Persistent_Context_Index.h>

Collaboration diagram for TAO_Persistent_Context_Index:

[legend]

List of all members.

Public Types
typedef ACE_Hash_Map_With_Allocator < TAO_Persistent_Index_ExtId, TAO_Persistent_Index_IntId >	CONTEXT_INDEX
	Hash map in which we will store info about each Persistent Naming Context.
typedef ACE_Hash_Map_With_Allocator < TAO_Persistent_ExtId, TAO_Persistent_IntId >	CONTEXT
	Hash map used by Persistent Naming Context to keep its state.
typedef ACE_Allocator_Adapter < ACE_Malloc < ACE_MMAP_MEMORY_POOL, TAO_SYNCH_MUTEX > >	ALLOCATOR
	Allocator we will be using to make the Naming Service persistent.
Public Member Functions
	TAO_Persistent_Context_Index (CORBA::ORB_ptr orb, PortableServer::POA_ptr poa)
	Constructor.
int	open (const ACE_TCHAR *file_name, void *base_address=TAO_NAMING_BASE_ADDR)
int	init (size_t context_size)
	~TAO_Persistent_Context_Index (void)
int	bind (const char *poa_id, ACE_UINT32 *&counter, CONTEXT *hash_map)
int	unbind (const char *poa_id)
ACE_Allocator *	allocator (void)
	Return allocator.
CORBA::ORB_ptr	orb (void)
	Return orb pointer.
CosNaming::NamingContext_ptr	root_context (void)
Private Member Functions
int	recreate_all (void)
int	create_index (void)
	Helper for the <open> method.
int	create_index_helper (void *buffer)
Private Attributes
TAO_SYNCH_MUTEX	lock_
ALLOCATOR *	allocator_
CONTEXT_INDEX *	index_
const ACE_TCHAR *	index_file_
	Name of the memory-mapped file used by <allocator_>.
void *	base_address_
	Base address for the memory-mapped file.
CORBA::ORB_var	orb_
PortableServer::POA_var	poa_
CosNaming::NamingContext_var	root_context_
	The reference to the root Naming Context.

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Detailed Description

This class facilitates implementation of Persistent Naming Service. It keeps track, centrally, of several pieces of info for each Persistent Naming Context, allowing to perform the initialization necessary for each Naming Context to restore the state of the Naming Service from persistent storage on server start-up.

This class creates a memory-mapped file, allocates a hash table from that file, and uses the hash table to store POA id, and table and counter pointers for each Persistent Naming Context. There are methods for adding and deleting entries from this hash table as new Persistent Naming Contexts are created and old ones are destroyed. This hash table facilitates Persistent Naming Context servant initialization upon Naming Server start-up.

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Member Typedef Documentation

typedef ACE_Hash_Map_With_Allocator<TAO_Persistent_Index_ExtId, TAO_Persistent_Index_IntId> TAO_Persistent_Context_Index::CONTEXT_INDEX

Hash map in which we will store info about each Persistent Naming Context.

typedef ACE_Hash_Map_With_Allocator<TAO_Persistent_ExtId, TAO_Persistent_IntId> TAO_Persistent_Context_Index::CONTEXT

Hash map used by Persistent Naming Context to keep its state.

typedef ACE_Allocator_Adapter<ACE_Malloc <ACE_MMAP_MEMORY_POOL, TAO_SYNCH_MUTEX> > TAO_Persistent_Context_Index::ALLOCATOR

Allocator we will be using to make the Naming Service persistent.

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Constructor & Destructor Documentation

TAO_Persistent_Context_Index::TAO_Persistent_Context_Index	(	CORBA::ORB_ptr	orb,
		PortableServer::POA_ptr	poa
	)

Constructor.

TAO_Persistent_Context_Index::~TAO_Persistent_Context_Index

(

void

)

Destructor. The memory mapped file that was opened/created is not deleted, since we want it to keep the state of the Naming Service until the next run.

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Member Function Documentation

int TAO_Persistent_Context_Index::open	(	const ACE_TCHAR *	file_name,
		void *	base_address = TAO_NAMING_BASE_ADDR
	)

Create ACE_Allocator, open/create memory-mapped file with the specified file name/base address. Find or allocate <index_>. Return 0 on success or -1 on failure.

int TAO_Persistent_Context_Index::init

(

size_t

context_size

)

If <index_> contains no entries (i.e., was just created), create a root Persistent Naming Context servant with table of size <context_size>, and make an entry for it in the <index_>. If <index_> contains entries, create a Persistent Naming Context servant for each entry. Return 0 on success and -1 on failure.

int TAO_Persistent_Context_Index::bind	(	const char *	poa_id,
		ACE_UINT32 *&	counter,
		TAO_Persistent_Context_Index::CONTEXT *	hash_map
	)

Create an entry for a Persistent Naming Context in <index_>, i.e., a context with <poa_id>, <counter> and <hash_map> has just been created, and is registering with us.

TAO_BEGIN_VERSIONED_NAMESPACE_DECL int TAO_Persistent_Context_Index::unbind

(

const char *

poa_id

)

Remove an entry for the Persistent Naming Context with <poa_id> from <index_> (i.e., this context has just been destroyed).

ACE_Allocator * TAO_Persistent_Context_Index::allocator

(

void

)

Return allocator.

CORBA::ORB_ptr TAO_Persistent_Context_Index::orb

(

void

)

Return orb pointer.

CosNaming::NamingContext_ptr TAO_Persistent_Context_Index::root_context

(

void

)

Return a pointer to the root Naming Context (returns a copy - must be deallocated by the user).

int TAO_Persistent_Context_Index::recreate_all

(

void

)

[private]

Helper for the <init> method. Iterates over <index_>, and creates a servant for each entry.

int TAO_Persistent_Context_Index::create_index

(

void

)

[private]

Helper for the <open> method.

int TAO_Persistent_Context_Index::create_index_helper

(

void *

buffer

)

[private]

Helper for <create_index> method: places hash table into an allocated space.

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Member Data Documentation

TAO_SYNCH_MUTEX TAO_Persistent_Context_Index::lock_ [private]

Lock to prevent multiple threads from modifying entries in the <index_> simultanneously.

ALLOCATOR* TAO_Persistent_Context_Index::allocator_ [private]

Allocator that deals out memory from a memory-mapped file. We use it here, and in TAO_Persistent_Naming_Context, whenever we deal with data that should be kept in persistent store.

CONTEXT_INDEX* TAO_Persistent_Context_Index::index_ [private]

Hash map where we keep entries for all Persistent Naming Contexts.

const ACE_TCHAR* TAO_Persistent_Context_Index::index_file_ [private]

Name of the memory-mapped file used by <allocator_>.

void* TAO_Persistent_Context_Index::base_address_ [private]

Base address for the memory-mapped file.

CORBA::ORB_var TAO_Persistent_Context_Index::orb_ [private]

ORB. We use it for several object_to_string conversions, and keep it around for Persistent Naming Contexts' use.

PortableServer::POA_var TAO_Persistent_Context_Index::poa_ [private]

POA under which to register Persistent Naming Context servants during start-up.

CosNaming::NamingContext_var TAO_Persistent_Context_Index::root_context_ [private]

The reference to the root Naming Context.

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

• Persistent_Context_Index.h
• Persistent_Context_Index.cpp

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