void CRUTopologicalDGIterator::Next()
{
RUASSERT(FALSE == allTasksLinkMap_.IsEmpty());
CRUTask *pTask = GetCurrentTask();
if (NULL == pTask)
{
return; // all the tasks have been already traversed
}
// The tasks that need to be traversed after me
CRUTaskList &refTaskList =
(DIRECT == dir_) ?
pTask->GetTasksThatDependOnMe() :
pTask->GetTasksThatIDependOn();
// For all of these tasks, decrecase the reference count
// Update the "ready" list, if any of the tasks have become ready.
UpdateIterator(refTaskList);
// Select a new current task
if (TRUE == readyTasksList_.IsEmpty())
{
SetCurrentTask(NULL); // The last task has just been traversed
}
else
{
// Retrieve a new task from the "ready" list
SetCurrentTask(readyTasksList_.RemoveHead());
}
}
void CRUTopologicalDGIterator::Build()
{
TaskLink link;
// Fill the data structures by references to available tasks
DSListPosition pos = GetAllTasksList().GetHeadPosition();
while (NULL != pos)
{
CRUTask *pTask = GetAllTasksList().GetNext(pos);
link.pTask_ = pTask;
// The tasks that need to be traversed before me
CRUTaskList &refTaskList =
(DIRECT == dir_) ?
pTask->GetTasksThatIDependOn() :
pTask->GetTasksThatDependOnMe();
link.refCount_ = refTaskList.GetCount();
// Place the link into the hash
allTasksLinkMap_[pTask->GetId()] = link;
// If this is a ready task,
// place a reference to it into the ready list
if (0 == link.refCount_)
{
readyTasksList_.AddHead(link.pTask_);
}
}
// My guess is that this is a circular graph
RUASSERT(FALSE == readyTasksList_.IsEmpty());
SetCurrentTask(readyTasksList_.RemoveHead());
}
void CRUTask::RemoveAllTasksThatDependOnMe()
{
DSListPosition pos = GetTasksThatDependOnMe().GetHeadPosition();
while (NULL != pos)
{
CRUTask *pToTask = GetTasksThatDependOnMe().GetNext(pos);
pToTask->GetTasksThatIDependOn().RemoveRefToTask(this);
}
GetTasksThatDependOnMe().RemoveAll();
}
