CSemaphore Class Reference
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#include <ncbimtx.hpp>

Collaboration diagram for CSemaphore:

[legend]List of all members.

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Detailed Description

CSemaphore --.

Implement the semantics of an application-wide semaphore.

Definition at line 1304 of file ncbimtx.hpp.

Public Member Functions
	CSemaphore (unsigned int init_count, unsigned int max_count)
	Constructor.
	~CSemaphore (void)
	Destructor.
void	Wait (void)
	Wait on semaphore.
bool	TryWait (unsigned int timeout_sec=0, unsigned int timeout_nsec=0)
	Timed wait.
void	Post (unsigned int count=1)
	Increment the semaphore by "count".
Private Member Functions
	CSemaphore (const CSemaphore &)
	Private copy constructor to disallow initialization.
CSemaphore &	operator= (const CSemaphore &)
	Private assignment operator to disallow assignment.
Private Attributes
SSemaphore *	m_Sem
	System-specific semaphore data.

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Constructor & Destructor Documentation

CSemaphore::CSemaphore (  unsigned int  init_count, unsigned int  max_count )

Constructor. Parameters: int_count  The initial value of the semaphore. max_count Maximum value that semaphore value can be incremented to. Definition at line 1014 of file ncbimtx.cpp. References SSemaphore::count, m_Sem, SSemaphore::max_count, auto_ptr< X >::release(), and xncbi_Validate.

CSemaphore::~CSemaphore (  void   )

Destructor. Report error if the semaphore is locked. Definition at line 1064 of file ncbimtx.cpp. References _ASSERT, m_Sem, and xncbi_Verify.

CSemaphore::CSemaphore (  const CSemaphore &   )  [private]

Private copy constructor to disallow initialization.

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Member Function Documentation

CSemaphore& CSemaphore::operator= (  const CSemaphore &   )  [private]

Private assignment operator to disallow assignment.

void CSemaphore::Post (  unsigned int  count = 1  )

Increment the semaphore by "count". Do nothing and throw an exception if counter would exceed "max_count". Definition at line 1216 of file ncbimtx.cpp. References _TROUBLE, SSemaphore::count, kMax_UInt, m_Sem, SSemaphore::max_count, and xncbi_Validate. Referenced by CPrefetchTokenOld_Impl::AddResolvedId(), CNCFileSystem::Finalize(), CBlockingQueue< TRequest >::GetHandle(), CGridWorkerNode::LeaveExclusiveMode(), CGridCleanupThread::Main(), CPrefetchTokenOld_Impl::NextBioseqHandle(), CScheduler_ExecThread_Impl::OnNextExecutionTimeChange(), CNCMMCentral::PrepareToStop(), CBlockingQueue< TRequest >::Put(), CPrefetchTokenOld_Impl::RemoveTokenReference(), CThreadNonStop::RequestDoJob(), CWorkerNodeIdleThread::RequestShutdown(), CThreadNonStop::RequestStop(), CReadPipeThread::RequestStop(), CWorkerNodeIdleThread::Schedule(), CScheduler_ExecThread_Impl::Stop(), CBDB_Cache::StopPurge(), CWorkerNodeIdleThread::Suspend(), CThreadPool_Impl::TaskFinished(), CThreadPool_Impl::ThreadStateChanged(), CGridWorkerNode::WaitForExclusiveJobToFinish(), CBlockingQueue< TRequest >::WaitForHunger(), CBlockingQueue< TRequest >::WaitForRoom(), CThreadPool_ThreadImpl::WakeUp(), CThreadPool_ServiceThread::WakeUp(), CNCFileSystem::x_AddNewEvent(), CNCFileSystem::x_DoBackgroundWork(), CReader::x_ReleaseConnection(), CSyncQueue< Type, Container >::x_Unlock(), and CNCBlobStorage::~CNCBlobStorage().

bool CSemaphore::TryWait (  unsigned int  timeout_sec = 0, unsigned int  timeout_nsec = 0 )

Timed wait. Wait up to timeout_sec + timeout_nsec/1E9 seconds for the semaphore's count to exceed zero. If that happens, decrement the counter by one and return TRUE; otherwise, return FALSE. Definition at line 1127 of file ncbimtx.cpp. References SSemaphore::count, kMax_Int, m_Sem, and xncbi_Validate. Referenced by CGridWorkerNode::EnterExclusiveMode(), CBlockingQueue< TRequest >::GetHandle(), CThreadNonStop::Main(), CScheduler_ExecThread_Impl::Main(), CReadPipeThread::Main(), CWorkerNodeIdleThread::Main(), CBlockingQueue< TRequest >::Put(), CGridCleanupThread::Wait(), CGridWorkerNode::WaitForExclusiveJobToFinish(), CNCBlobStorage::x_DoBackgroundWork(), CNCMMCentral::x_DoBackgroundWork(), CNCBlobStorage::x_GC_CleanDBVolume(), CSyncQueue< Type, Container >::x_Lock(), CThreadPool_Impl::x_WaitForPredicate(), and CBlockingQueue< TRequest >::x_WaitForPredicate().

void CSemaphore::Wait (  void   )

Wait on semaphore. Decrement the counter by one. If the semaphore's count is zero then wait until it's not zero. Definition at line 1079 of file ncbimtx.cpp. References SSemaphore::count, m_Sem, and xncbi_Validate. Referenced by CNCFileSystem::WriteToFile(), CReader::x_AllocConnection(), CThreadPool_ThreadImpl::x_Idle(), CSyncQueue< Type, Container >::x_Lock(), CThreadPool_ServiceThread::x_WaitForPoolStop(), and CThreadPool_Impl::x_WaitForPredicate().

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Member Data Documentation

struct SSemaphore* CSemaphore::m_Sem [private]

System-specific semaphore data. Definition at line 1338 of file ncbimtx.hpp. Referenced by CSemaphore(), Post(), TryWait(), Wait(), and ~CSemaphore().

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

• include/corelib/ncbimtx.hpp
• src/corelib/ncbimtx.cpp

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