Implementation of thread pool class. More...

#include <CXPlatThreadPool.h>

Public Types
enum	{ TP_REQUEST_EXCEEDS_POOL_SIZE = -1, TP_NOT_ENOUGH_THREADS_AVAILABLE = -2, TP_ZERO_THREADS_REQUESTED = -3, TP_NO_THREADS_IN_POOL = -4, TP_WAIT_TIMED_OUT = -5 }
Public Member Functions
	CXPlatThreadPool (int iPoolSize=5, int iMaxSize=0, int iGrowBy=1)
	Initial poolsize, maximum size to grow to, size to grow by when pool is grown.
virtual	~CXPlatThreadPool ()
int	GetAvailableThreads (THREAD_POOL_ARRAY &cAvailThreadPool, int iNeeded, BOOL bWaitForAtLeastOne=TRUE, DWORD dwWaitTime=INFINITE)
int	QueryThreadsAvailable ()
int	GetCurrentSizeOfPool ()
	Get how many threads are in the pool.
int	GetMaxSize ()
	Get the maximum size the thread pool can grow to.
void	SetMaxSize (int iMaxSize)
	Set the maximum size the thread pool can grow to.
void	WaitForAllThreadsToFinish ()
	Wait for all threads to finish. Do NOT call GetAvailableThreads at the same time.
void	ShrinkPool ()
	Shrink the thread pool by one thread.
void	SetFinishWaitTime (unsigned long lWaitTime)
	Set the wait time when we are waiting for all threads to finish.
Protected Member Functions
virtual CXPlatPooledThread *	AllocatePooledThread ()=0
	Implement to allocate the proper type of derived pooled thread.
BOOL	GrowThreadPool (BOOL bInit=FALSE)
	Add threads to the pool.
BOOL	Init ()
Protected Attributes
THREAD_POOL_ARRAY	cThreadPool
CXPlatCriticalSection	cPoolCritSect
	Our pool of threads.
CXPlatEvent	cThreadAvailableEvent
	To protect ThreadPool.
int	iOriginalThreadsInPool
	Threads will set when they become available.
int	iThreadsInPool
int	iMaxThreadsAllowed
int	iGrowBy
bool	bShrinking
unsigned long	lWaitToFinish
bool	bWaitToFinishSet
Friends
class	CXPlatPooledThread

Detailed Description

Implementation of thread pool class.

Definition at line 37 of file CXPlatThreadPool.h.

Member Enumeration Documentation

anonymous enum

Enumerator:

TP_REQUEST_EXCEEDS_POOL_SIZE
TP_NOT_ENOUGH_THREADS_AVAILABLE
TP_ZERO_THREADS_REQUESTED
TP_NO_THREADS_IN_POOL
TP_WAIT_TIMED_OUT

Definition at line 46 of file CXPlatThreadPool.h.

Constructor & Destructor Documentation

CXPlatThreadPool::CXPlatThreadPool	(	int	iPoolSize = `5`,
		int	iMaxSize = `0`,
		int	iGrowBy = `1`
	)

Initial poolsize, maximum size to grow to, size to grow by when pool is grown.

CXPlatThreadPool.cpp: implementation of the CXPlatThreadPool class.

This class manages a pool of CXPlatPooledThread objects

Definition at line 31 of file CXPlatThreadPool.cpp.

CXPlatThreadPool::~CXPlatThreadPool ( ) [virtual]

Definition at line 51 of file CXPlatThreadPool.cpp.

Member Function Documentation

virtual CXPlatPooledThread* CXPlatThreadPool::AllocatePooledThread ( ) [protected, pure virtual]

Implement to allocate the proper type of derived pooled thread.

int CXPlatThreadPool::GetAvailableThreads	(	THREAD_POOL_ARRAY &	cAvailThreadPool,
		int	iNeeded,
		BOOL	bWaitForAtLeastOne = `TRUE`,
		DWORD	dwWaitTime = `INFINITE`
	)

Array will be set with available thread objects.

If the return is > 0, it's the number of threads returned. A return of < 0 will be one of the above error enums.

If bWaitForAtLeastOne == TRUE, at least one thread must become available or the call will wait dwWaitTime ms before returning.

Threads returned will be marked as allocated until the CXPlatPooledThread::PooledWorkerFunction returns. If CXPlatPooledThread::StartWorking is never called, this thread will never become available again.

Definition at line 138 of file CXPlatThreadPool.cpp.

int CXPlatThreadPool::GetCurrentSizeOfPool ( )

Get how many threads are in the pool.

Definition at line 296 of file CXPlatThreadPool.cpp.

int CXPlatThreadPool::GetMaxSize ( )

Get the maximum size the thread pool can grow to.

Definition at line 311 of file CXPlatThreadPool.cpp.

BOOL CXPlatThreadPool::GrowThreadPool ( BOOL bInit = FALSE ) [protected]

Add threads to the pool.

Definition at line 82 of file CXPlatThreadPool.cpp.

BOOL CXPlatThreadPool::Init ( ) [protected]

Derived classes should call this to initial the thread pool Can be called in the constructor

Definition at line 71 of file CXPlatThreadPool.cpp.

int CXPlatThreadPool::QueryThreadsAvailable ( )

How many threads are currently unallocated by requests? Note that you cannot depend on these threads remaining available if there is more than one than one thread of execution in your program that dispatches the threads.

Definition at line 266 of file CXPlatThreadPool.cpp.

void CXPlatThreadPool::SetFinishWaitTime ( unsigned long lWaitTime )

Set the wait time when we are waiting for all threads to finish.

Definition at line 333 of file CXPlatThreadPool.cpp.

void CXPlatThreadPool::SetMaxSize ( int iMaxSize )

Set the maximum size the thread pool can grow to.

Definition at line 318 of file CXPlatThreadPool.cpp.

void CXPlatThreadPool::ShrinkPool ( )

Shrink the thread pool by one thread.

Definition at line 114 of file CXPlatThreadPool.cpp.

void CXPlatThreadPool::WaitForAllThreadsToFinish ( )

Wait for all threads to finish. Do NOT call GetAvailableThreads at the same time.