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Diffstat (limited to 'TAO/orbsvcs/orbsvcs/Concurrency/CC_LockSet.h')
| -rw-r--r-- | TAO/orbsvcs/orbsvcs/Concurrency/CC_LockSet.h | 174 |
1 files changed, 0 insertions, 174 deletions
diff --git a/TAO/orbsvcs/orbsvcs/Concurrency/CC_LockSet.h b/TAO/orbsvcs/orbsvcs/Concurrency/CC_LockSet.h deleted file mode 100644 index 5b6087189c5..00000000000 --- a/TAO/orbsvcs/orbsvcs/Concurrency/CC_LockSet.h +++ /dev/null @@ -1,174 +0,0 @@ -/* -*- C++ -*- */ -// $Id$ - -// ============================================================================ -// -// = LIBRARY -// TAO/orbsvcs/Concurrency_Service -// -// = FILENAME -// CC_LockSet.h -// -// = DESCRIPTION -// This class implements the lock set interface from the -// concurrency service. -// -// In the present implementation the multiple possesion semantics -// is implemented for non-transactional clients. In future -// versions this should be changed because the multiple possesion -// semantics does not apply to non-transactional clients. This -// can be accomplished in the following manner: -// - Make a class with the same functiallity as the CC_LockSet -// class as a base class for both implementations. -// - The functionallity that should be separated out in the -// subclasses is the compatible function which should always -// return false because no locks can be held simultanously with -// non-transactional clients. -// - Use these classes from the classes that inherits the -// servant properties, i.e. the way CC_LockSet does now. -// -// = AUTHORS -// Torben Worm <tworm@cs.wustl.edu> -// -// ============================================================================ - -#ifndef _CC_LOCKSET_H -#define _CC_LOCKSET_H - -#include "ace/Synch.h" - -#if !defined (ACE_LACKS_PRAGMA_ONCE) -# pragma once -#endif /* ACE_LACKS_PRAGMA_ONCE */ - -#include "ace/Token.h" -#include "orbsvcs/CosConcurrencyControlS.h" - -#define NUMBER_OF_LOCK_MODES 5 -// This constant defines the number of lock modes. There is really no -// way to set this constant dynamically because the nuber of lock -// modes are not stated as part of the IDL. - -typedef enum {CC_EM=-1, CC_IR=0, CC_R, CC_U, CC_IW, CC_W} CC_LockModeEnum; -// Enummeration representing the lock modes. The incomming request is -// always converted to this representation. There are two reasons for -// this: Firstly the lock modes are ordered from weakest to strongest -// in the internal representation, and secondly it is possible to -// indicate a 'non-mode' (CC_EM) - -class TAO_ORBSVCS_Export CC_LockSet : public POA_CosConcurrencyControl::LockSet -{ - // = TITLE - // CC_LockSet - // - // = DESCRIPTION - // This class implements the LockSet interface that is part of - // the CosConcurrency service. Please consult the idl file for - // detailed descriptions apart from the comments in this file At - // present the lock set is not really a set, but only one lock. -public: - - // = Initialization and termination methods. - CC_LockSet (void); - // Default constructor - - CC_LockSet (CosConcurrencyControl::LockSet_ptr related); - // Constructor used if create_related is used to create the lock - // set. - - ~CC_LockSet (void); - // Destructor. - - // = CosConcurrencyControl methods - virtual void lock (CosConcurrencyControl::lock_mode mode, - CORBA::Environment &env); - // Acquires this lock. Blocks until lock is obtained - - virtual CORBA::Boolean try_lock (CosConcurrencyControl::lock_mode mode, - CORBA::Environment &env); - // Tries to acquire this lock. If it is not possible to acquire the - // lock, false is returned - - virtual void unlock (CosConcurrencyControl::lock_mode mode, - CORBA::Environment &env); - // Releases this lock. - - virtual void change_mode (CosConcurrencyControl::lock_mode held_mode, - CosConcurrencyControl::lock_mode new_mode, - CORBA::Environment &env); - // Changes the mode of this lock. - - // = Debugging methods - void dump (void); - // Dump the state of the object to stdout - -private: - CC_LockModeEnum lmconvert (CosConcurrencyControl::lock_mode mode); - // Converts the CORBA specification's lock mode to the internal - // representation - - void Init (CORBA::Environment &_env); - // Initiatlizes the lock set array and acquires the initial - // semaphore. - - CORBA::Boolean compatible (CC_LockModeEnum mr); - // Returns true if the held lock and the requested lock are compatible - - // The _i functions below ensures atomical access the the state data - // for the lock set. The functions acquires a thread lock in order - // to insure consistency within the lock set. The return value - // typically indicates whether the current thread should be - // suspended or not (by locking the semaphore. - - int lock_i (CC_LockModeEnum lm); - // Locks the access to the data and decides whether to lock or - // not. Returns 1 if the semaphore should be locked. - - // int unlock_i (CosConcurrencyControl::lock_mode lm); - // This function is not necessary because we lock access to the data - // and unlocks the semaphore until an invalid lock mode is first on - // the queue. Thereafter we release the lock. - - int try_lock_i (CC_LockModeEnum lm); - // Locks the access to the data and determines whether to return - // true or false. Returns 1 if true should be returned. - - int change_mode_i (CC_LockModeEnum lm_held, - CC_LockModeEnum lm_new); - // Locks access to the data and determines if the semaphore should - // be locked. Returns 1 if the semaphore should be locked. - - int lock_held (CC_LockModeEnum lm); - // Locks access ti the data and checks whether the lock is held. - - int lock_[NUMBER_OF_LOCK_MODES]; - // An array of lock counters that counts how many locks of that type - // that the lock set holds. - - // ACE_Thread_Semaphore semaphore_; - ACE_Token semaphore_; - // This is the semaphore for the lock set. The semaphore is used to - // queue requests for locks in modes stronger than currently - // possible to grant. Note that the <ACE_Token> provides strict - // FIFO ordering of acquisition/release of the lock. - - CosConcurrencyControl::LockSet_ptr related_lockset_; - // If this lock set is related to another lock set, this is the - // pointer to the related lock set. This is a really simple - // solution, but since transactions are not supported in the first - // version there should be no reason to drop lock sets together. The - // <LockSetCoordinator> is not implemented (it has the - // responsibilities of dropping the locks). - - static CORBA::Boolean compatible_[NUMBER_OF_LOCK_MODES][NUMBER_OF_LOCK_MODES]; - // Mapping between requested and held lock modes. Used by compatible - // (...). Uses the internal enumeration as indices. - - ACE_SYNCH_MUTEX mlock_; - // Lock to ensure that race conditions does not occur. - - ACE_Unbounded_Queue <CC_LockModeEnum> lock_queue_; - // Queue to hold the requested locks not yet granted. -}; - -#endif /* _CC_LOCKSET_H */ |