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ACE_RW_Process_Mutex Class Reference

Wrapper for readers/writer locks that exist across processes. More...

#include <RW_Process_Mutex.h>

Collaboration diagram for ACE_RW_Process_Mutex:

Public Methods
	ACE_RW_Process_Mutex (const ACE_TCHAR *name=0, int flags=O_CREAT\|O_RDWR)
	Create a readers/writer <Process_Mutex>, passing in the optional <name>. If not specified, a name is generated. More...
	~ACE_RW_Process_Mutex (void)
int	remove (void)
int	acquire (void)
	Acquire lock ownership (wait on queue if necessary). More...
int	tryacquire (void)
int	release (void)
	Release lock and unblock a thread at head of queue. More...
int	acquire_read (void)
	Acquire lock ownership (wait on queue if necessary). More...
int	acquire_write (void)
	Acquire lock ownership (wait on queue if necessary). More...
int	tryacquire_read (void)
int	tryacquire_write (void)
int	tryacquire_write_upgrade (void)
	Attempt to upgrade a read lock to a write lock. Returns 0 on success, -1 on failure. More...
const ACE_File_Lock &	lock (void) const
	Return the underlying lock. More...
void	dump (void) const
	Dump the state of an object. More...
Public Attributes
	ACE_ALLOC_HOOK_DECLARE
	Declare the dynamic allocation hooks. More...
Private Methods
const ACE_TCHAR *	unique_name (void)
	Create and return the unique name. More...
Private Attributes
ACE_TCHAR	name_ [ACE_UNIQUE_NAME_LEN]
	If the user does not provide a name we generate a unique name in this buffer. More...
ACE_File_Lock	lock_
	We need this to get the readers/writer semantics... More...

Detailed Description

Wrapper for readers/writer locks that exist across processes.

Note that because this class uses the <ACE_File_Lock> as its implementation it only can be reliably used between separate processes, rather than threads in the same process. This isn't a limitation of ACE, it's simply the file lock semantics on UNIX and Win32.

Definition at line 34 of file RW_Process_Mutex.h.

Constructor & Destructor Documentation

ACE_RW_Process_Mutex::ACE_RW_Process_Mutex ( const ACE_TCHAR * name = 0,

int flags = O_CREAT|O_RDWR

)

Create a readers/writer <Process_Mutex>, passing in the optional <name>. If not specified, a name is generated.

Definition at line 23 of file RW_Process_Mutex.cpp.
References ACE_DEFAULT_OPEN_PERMS, and ACE_TCHAR.

00025 : lock_ (name ? name : this->unique_name (), flags 00026 #if defined (ACE_WIN32) 00027 , ACE_DEFAULT_OPEN_PERMS) 00028 #else 00029 , S_IRUSR | S_IWUSR) 00030 #endif /* ACE_WIN32 */ 00031 { 00032 // ACE_TRACE ("ACE_RW_Process_Mutex::ACE_RW_Process_Mutex"); 00033 }

ACE_RW_Process_Mutex::~ACE_RW_Process_Mutex ( void )

Definition at line 35 of file RW_Process_Mutex.cpp.

00036 { 00037 // ACE_TRACE ("ACE_RW_Process_Mutex::~ACE_RW_Process_Mutex"); 00038 }

Member Function Documentation

ACE_INLINE int ACE_RW_Process_Mutex::acquire ( void )

Acquire lock ownership (wait on queue if necessary).

Definition at line 13 of file RW_Process_Mutex.inl.
References ACE_File_Lock::acquire, and lock_.

00014 { 00015 return this->lock_.acquire (); 00016 }

ACE_INLINE int ACE_RW_Process_Mutex::acquire_read ( void )

Acquire lock ownership (wait on queue if necessary).

Definition at line 34 of file RW_Process_Mutex.inl.
References ACE_File_Lock::acquire_read, and lock_.

00035 { 00036 return this->lock_.acquire_read (); 00037 }

ACE_INLINE int ACE_RW_Process_Mutex::acquire_write ( void )

Acquire lock ownership (wait on queue if necessary).

Definition at line 41 of file RW_Process_Mutex.inl.
References ACE_File_Lock::acquire_write, and lock_.

00042 { 00043 return this->lock_.acquire_write (); 00044 }

void ACE_RW_Process_Mutex::dump ( void ) const

Dump the state of an object.

Definition at line 41 of file RW_Process_Mutex.cpp.
References ACE_BEGIN_DUMP, ACE_DEBUG, ACE_END_DUMP, ACE_File_Lock::dump, LM_DEBUG, and lock_.

00042 { 00043 // ACE_TRACE ("ACE_RW_Process_Mutex::dump"); 00044 ACE_DEBUG ((LM_DEBUG, ACE_BEGIN_DUMP, this)); 00045 this->lock_.dump (); 00046 ACE_DEBUG ((LM_DEBUG, ACE_END_DUMP)); 00047 }

ACE_INLINE const ACE_File_Lock & ACE_RW_Process_Mutex::lock ( void ) const

Return the underlying lock.

Definition at line 68 of file RW_Process_Mutex.inl.
References lock_.

00069 { 00070 // ACE_TRACE ("ACE_RW_Process_Mutex::lock"); 00071 return this->lock_; 00072 }

ACE_INLINE int ACE_RW_Process_Mutex::release ( void )

Release lock and unblock a thread at head of queue.

Definition at line 27 of file RW_Process_Mutex.inl.
References lock_, and ACE_File_Lock::release.

00028 { 00029 return this->lock_.release (); 00030 }

ACE_INLINE int ACE_RW_Process_Mutex::remove ( void )

Explicitly destroy the mutex. Note that only one thread should call this method since it doesn't protect against race conditions.
Definition at line 6 of file RW_Process_Mutex.inl.
References lock_, and ACE_File_Lock::remove.

00007 { 00008 return this->lock_.remove (); 00009 }

ACE_INLINE int ACE_RW_Process_Mutex::tryacquire ( void )

Conditionally acquire lock (i.e., don't wait on queue). Returns -1 on failure. If we "failed" because someone else already had the lock, <errno> is set to <EBUSY>.
Definition at line 20 of file RW_Process_Mutex.inl.
References lock_, and ACE_File_Lock::tryacquire.

00021 { 00022 return this->lock_.tryacquire (); 00023 }

ACE_INLINE int ACE_RW_Process_Mutex::tryacquire_read ( void )

Conditionally acquire a 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>.
Definition at line 48 of file RW_Process_Mutex.inl.
References lock_, and ACE_File_Lock::tryacquire_read.

00049 { 00050 return this->lock_.tryacquire_read (); 00051 }

ACE_INLINE int ACE_RW_Process_Mutex::tryacquire_write ( void )

Conditionally acquire a 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>.
Definition at line 55 of file RW_Process_Mutex.inl.
References lock_, and ACE_File_Lock::tryacquire_write.

00056 { 00057 return this->lock_.tryacquire_write (); 00058 }

ACE_INLINE int ACE_RW_Process_Mutex::tryacquire_write_upgrade ( void )

Attempt to upgrade a read lock to a write lock. Returns 0 on success, -1 on failure.

Definition at line 62 of file RW_Process_Mutex.inl.
References lock_, and ACE_File_Lock::tryacquire_write_upgrade.

00063 { 00064 return this->lock_.tryacquire_write_upgrade (); 00065 }

const ACE_TCHAR * ACE_RW_Process_Mutex::unique_name ( void ) [private]

Create and return the unique name.

Definition at line 17 of file RW_Process_Mutex.cpp.
References ACE_UNIQUE_NAME_LEN, name_, and ACE::unique_name.

00018 { 00019 ACE::unique_name (this, this->name_, ACE_UNIQUE_NAME_LEN); 00020 return this->name_; 00021 }

Member Data Documentation

ACE_RW_Process_Mutex::ACE_ALLOC_HOOK_DECLARE

Declare the dynamic allocation hooks.

Definition at line 95 of file RW_Process_Mutex.h.

ACE_File_Lock ACE_RW_Process_Mutex::lock_ [private]

We need this to get the readers/writer semantics...

Definition at line 106 of file RW_Process_Mutex.h.
Referenced by acquire, acquire_read, acquire_write, dump, lock, release, remove, tryacquire, tryacquire_read, tryacquire_write, and tryacquire_write_upgrade.

ACE_TCHAR ACE_RW_Process_Mutex::name_[ACE_UNIQUE_NAME_LEN] [private]

If the user does not provide a name we generate a unique name in this buffer.

Definition at line 100 of file RW_Process_Mutex.h.
Referenced by unique_name.

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

Generated on Mon Jun 16 12:55:27 2003 for ACE by

ACE_RW_Process_Mutex Class Reference

Public Methods

Public Attributes

Private Methods

Private Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation