ACE  6.1.7
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Public Member Functions | Public Attributes | Protected Attributes | Private Member Functions
ACE_RW_Mutex Class Reference

Wrapper for readers/writer locks. More...

#include <RW_Mutex.h>

Inheritance diagram for ACE_RW_Mutex:
Inheritance graph
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List of all members.

Public Member Functions

 ACE_RW_Mutex (int type=USYNC_THREAD, const ACE_TCHAR *name=0, void *arg=0)
 Initialize a readers/writer lock.
 ~ACE_RW_Mutex (void)
 Implicitly destroy a readers/writer lock.
int remove (void)
int acquire_read (void)
 Acquire a read lock, but block if a writer hold the lock.
int acquire_write (void)
int tryacquire_read (void)
int tryacquire_write (void)
 Conditionally acquire a write lock (i.e., won't block).
int tryacquire_write_upgrade (void)
int acquire (void)
int tryacquire (void)
int release (void)
 Unlock a readers/writer lock.
const ACE_rwlock_t & lock (void) const
 Return the underlying lock.
void dump (void) const
 Dump the state of an object.

Public Attributes

 ACE_ALLOC_HOOK_DECLARE
 Declare the dynamic allocation hooks.

Protected Attributes

ACE_rwlock_t lock_
 Readers/writer lock.
bool removed_

Private Member Functions

void operator= (const ACE_RW_Mutex &)
 ACE_RW_Mutex (const ACE_RW_Mutex &)

Detailed Description

Wrapper for readers/writer locks.

These are most useful for applications that have many more parallel readers than writers...


Constructor & Destructor Documentation

ACE_RW_Mutex::ACE_RW_Mutex ( int  type = USYNC_THREAD,
const ACE_TCHAR name = 0,
void *  arg = 0 
)

Initialize a readers/writer lock.

ACE_RW_Mutex::~ACE_RW_Mutex ( void  )

Implicitly destroy a readers/writer lock.

ACE_RW_Mutex::ACE_RW_Mutex ( const ACE_RW_Mutex )
private

Member Function Documentation

int ACE_RW_Mutex::acquire ( void  )
inline

Note, for interface uniformity with other synchronization wrappers we include the <acquire> method. This is implemented as a write-lock to safe...

int ACE_RW_Mutex::acquire_read ( void  )
inline

Acquire a read lock, but block if a writer hold the lock.

int ACE_RW_Mutex::acquire_write ( void  )
inline

Acquire a write lock, but block if any readers or a writer hold the lock.

void ACE_RW_Mutex::dump ( void  ) const

Dump the state of an object.

Reimplemented in ACE_RW_Thread_Mutex.

const ACE_rwlock_t & ACE_RW_Mutex::lock ( void  ) const
inline

Return the underlying lock.

void ACE_RW_Mutex::operator= ( const ACE_RW_Mutex )
private
int ACE_RW_Mutex::release ( void  )
inline

Unlock a readers/writer lock.

int ACE_RW_Mutex::remove ( void  )
inline

Explicitly destroy a readers/writer lock. Note that only one thread should call this method since it doesn't protect against race conditions.

int ACE_RW_Mutex::tryacquire ( void  )
inline

Note, for interface uniformity with other synchronization wrappers we include the tryacquire() method. This is implemented as a write-lock to be safe... Returns -1 on failure. If we "failed" because someone else already had the lock, errno is set to EBUSY.

int ACE_RW_Mutex::tryacquire_read ( void  )
inline

Conditionally acquire a read lock (i.e., won't block). Returns -1 on failure. If we "failed" because someone else already had the lock, errno is set to EBUSY.

int ACE_RW_Mutex::tryacquire_write ( void  )
inline

Conditionally acquire a write lock (i.e., won't block).

int ACE_RW_Mutex::tryacquire_write_upgrade ( void  )
inline

Conditionally upgrade a read lock to a write lock. This only works if there are no other readers present, in which case the method returns 0. Otherwise, the method returns -1 and sets errno to EBUSY. Note that the caller of this method must already possess this lock as a read lock (but this condition is not checked by the current implementation).

Reimplemented in ACE_RW_Thread_Mutex.


Member Data Documentation

ACE_RW_Mutex::ACE_ALLOC_HOOK_DECLARE

Declare the dynamic allocation hooks.

Reimplemented in ACE_RW_Thread_Mutex.

ACE_rwlock_t ACE_RW_Mutex::lock_
protected

Readers/writer lock.

bool ACE_RW_Mutex::removed_
protected

Keeps track of whether remove() has been called yet to avoid multiple remove() calls, e.g., explicitly and implicitly in the destructor. This flag isn't protected by a lock, so make sure that you don't have multiple threads simultaneously calling remove() on the same object, which is a bad idea anyway...


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