Files
epics-base/src/libCom/cxxTemplates/epicsOnce.cpp
2002-03-21 23:52:51 +00:00

86 lines
2.0 KiB
C++

/*
* $Id$
*
*
* L O S A L A M O S
* Los Alamos National Laboratory
* Los Alamos, New Mexico 87545
*
* Copyright, 1986, The Regents of the University of California.
*
*
* Author Jeff Hill
* johill@lanl.gov
* 505 665 1831
*/
#define epicsExportSharedSymbols
#include "epicsMutex.h"
#include "epicsSingleton.h"
#include "epicsGuard.h"
#include "epicsOnce.h"
#include "tsFreeList.h"
class epicsOnceImpl : public epicsOnce {
public:
epicsOnceImpl ( epicsOnceNotify & notifyIn );
void * operator new ( size_t size );
void operator delete ( void * pCadaver, size_t size );
private:
epicsOnceNotify & notify;
bool onceFlag;
void destroy ();
void once ();
static epicsSingleton < epicsMutex > pMutex;
static epicsSingleton < tsFreeList < class epicsOnceImpl, 16 > > pFreeList;
};
epicsSingleton < epicsMutex > epicsOnceImpl::pMutex;
epicsSingleton < tsFreeList < class epicsOnceImpl, 16 > > epicsOnceImpl::pFreeList;
inline void * epicsOnceImpl::operator new ( size_t size )
{
return epicsOnceImpl::pFreeList->allocate ( size );
}
inline void epicsOnceImpl::operator delete ( void *pCadaver, size_t size )
{
epicsOnceImpl::pFreeList->release ( pCadaver, size );
}
inline epicsOnceImpl::epicsOnceImpl ( epicsOnceNotify & notifyIn ) :
notify ( notifyIn ), onceFlag ( false )
{
}
void epicsOnceImpl::once ()
{
if ( ! this->onceFlag ) {
epicsGuard < epicsMutex > guard ( *this->pMutex );
if ( ! this->onceFlag ) {
this->notify.initialize ();
this->onceFlag = true;
}
}
}
void epicsOnceImpl::destroy ()
{
delete this;
}
epicsOnce & epicsOnce::create ( epicsOnceNotify & notifyIn )
{
// free list throws exception in no memory situation
return * new epicsOnceImpl ( notifyIn );
}
epicsOnce::~epicsOnce ()
{
}
epicsOnceNotify::~epicsOnceNotify ()
{
}