ucommon::Semaphore Class Reference

A portable counting semaphore class. More...

#include <thread.h>

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Public Member Functions

void operator++ (void)
 Convenience operator to wait on a counting semaphore.
void operator-- (void)
 Convenience operator to release a counting semaphore.
void release (void)
 Release the semaphore after waiting for it.
 Semaphore (unsigned count=0)
 Construct a semaphore with an initial count of threads to permit.
void set (unsigned count)
 Alter semaphore limit at runtime.
bool wait (timeout_t timeout)
 Wait until the semphore usage count is less than the thread limit.
void wait (void)
 Wait until the semphore usage count is less than the thread limit.

Protected Member Functions

virtual void _share (void)
 Access interface to share lock the object.
virtual void _unlock (void)

Protected Attributes

unsigned count
unsigned used
unsigned waits

Detailed Description

A portable counting semaphore class.

A semaphore will allow threads to pass through it until the count is reached, and blocks further threads. Unlike pthread semaphore, our semaphore class supports it's count limit to be altered during runtime and the use of timed waits. This class also implements the shared_lock protocol.

Author:
David Sugar <dyfet@gnutelephony.org>

Definition at line 853 of file thread.h.


Member Function Documentation

void ucommon::Semaphore::set ( unsigned  count  ) 

Alter semaphore limit at runtime.

Parameters:
count of threads to allow.
bool ucommon::Semaphore::wait ( timeout_t  timeout  ) 

Wait until the semphore usage count is less than the thread limit.

Increase used count for our thread when unblocked, or return without changing if timed out.

Parameters:
timeout to wait in millseconds.
Returns:
true if success, false if timeout.

Reimplemented from ucommon::Conditional.

void ucommon::Semaphore::wait ( void   ) 

Wait until the semphore usage count is less than the thread limit.

Increase used count for our thread when unblocked.

Reimplemented from ucommon::Conditional.


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

Generated on 30 Jul 2013 for UCommon by  doxygen 1.6.1