///////////////////////////////////////////////////////////////////////////////
// Attach - Associate an observer with this subject
Error CSubject::Attach(IObserver* pObserver,
System::Types::BitMask inInterest,
u32 uID,
u32 shift)
{
// To make compiler happy in release builds while keeping the next assertion
UNREFERENCED_PARAM (shift);
// If the following assertion fails, it means that Change Control Manager (CCM)
// was modified to start using "shifts". Please update the code of this class
// appropriately (original version did not have any meaningful support except
// shifting inInterest on entry)
ASSERT (!shift && "CSubject::Attach: Interest bits are shifted. Read the comment to this assertion");
// Since the intended usage model is to use this method from CCMs only, and
// their implementation provided by this framework ensures that pObs in nonzero
// the following assertion should suffice.
ASSERT( pObserver && "CSubject::Attach: Valid pointer to observer object must be specified" );
#if SUPPORT_CONCURRENT_ATTACH_DETACH_TO_SUBJECTS
SpinWait::Lock lock(m_observerListMutex);
#endif
// Framework's CCM implementation ensures that the following assertion always holds
ASSERT( std::find(m_observerList.begin(), m_observerList.end(), pObserver) == m_observerList.end() &&
"CSubject::Attach: Observer has already been attached. Use CSubject::UpdateInterestBits instead." );
// Add the observer to our list of observers
m_observerList.push_back( ObserverRequest(pObserver, inInterest, uID) );
return Errors::Success;
}
///////////////////////////////////////////////////////////////////////////////
// Register - Register a new subject/observer relationsship
Error ChangeManager::Register(ISubject* pInSubject, System::Changes::BitMask observerIntrestBits, IObserver* pInObserver, System::Types::BitMask observerIdBits) {
Error curError = Errors::Failure;
if (pInSubject && pInObserver) {
// Lock out updates while we register a subjext
SCOPED_SPIN_LOCK(m_swUpdate);
u32 uID = pInSubject->getObserverId(this);
if (uID != ISubject::InvalidObserverID) {
// Subject has already been registered. Add new observer to the list
SubjectInfo& si = m_subjectsList[uID];
si.m_observersList.push_back(ObserverRequest(pInObserver, observerIntrestBits, observerIdBits));
observerIntrestBits &= ~si.m_interestBits;
if (observerIntrestBits) {
si.m_interestBits |= observerIntrestBits;
pInSubject->UpdateInterestBits(this, observerIntrestBits);
}
} else {
// New subject
if (m_freeIDsList.empty()) {
// No zero ID should ever be assigned, so use pre-increment
uID = ++m_lastID;
ASSERT(uID == m_subjectsList.size());
m_subjectsList.resize(uID + 1);
} else {
uID = m_freeIDsList.back();
m_freeIDsList.pop_back();
}
SubjectInfo& si = m_subjectsList[uID];
si.m_pSubject = pInSubject;
si.m_observersList.push_back(ObserverRequest(pInObserver, observerIntrestBits, observerIdBits));
si.m_interestBits = observerIntrestBits;
pInSubject->Attach(this, observerIntrestBits, uID);
}
curError = Errors::Success;
}
return curError;
}
///////////////////////////////////////////////////////////////////////////////
// Register - Register a new subject/observer relationsship
Error ChangeManager::Register(ISystemObject* pInSubject, IObserver* pInObserver) {
BOOST_ASSERT_MSG(pInSubject != nullptr, "Subject cannot be null");
BOOST_ASSERT_MSG(pInObserver != nullptr, "Observer cannot be null");
auto observerIntrestBits = pInObserver->GetDesiredSystemChanges();
if (pInSubject->GetPotentialSystemChanges() & observerIntrestBits) {
// Lock out updates while we register a subject
tbb::spin_mutex::scoped_lock _lock(m_swUpdate);
unsigned int uID = pInSubject->getObserverId(this);
if (uID != ISystemObject::InvalidObserverID) {
// Subject has already been registered. Add new observer to the list
SubjectInfo &si = m_subjectsList[uID];
si.m_observersList.push_back(ObserverRequest(pInObserver, uID, observerIntrestBits));
observerIntrestBits &= ~si.m_interestBits;
if (observerIntrestBits) {
si.m_interestBits |= observerIntrestBits;
pInSubject->UpdateInterestBits(this, observerIntrestBits);
}
} else {
// New subject
if (m_freeIDsList.empty()) {
// No zero ID should ever be assigned, so use pre-increment
uID = ++m_lastID;
BOOST_ASSERT(uID == m_subjectsList.size());
m_subjectsList.resize(uID + 1);
} else {
uID = m_freeIDsList.back();
m_freeIDsList.pop_back();
}
SubjectInfo &si = m_subjectsList[uID];
si.m_pSubject = pInSubject;
si.m_observersList.push_back(ObserverRequest(pInObserver, uID, observerIntrestBits));
si.m_interestBits = observerIntrestBits;
pInSubject->Attach(this, observerIntrestBits, uID);
}
}
return Errors::Success;
}
