summaryrefslogtreecommitdiffstats
path: root/src
diff options
context:
space:
mode:
Diffstat (limited to 'src')
-rw-r--r--src/OSSupport/Queue.h145
1 files changed, 86 insertions, 59 deletions
diff --git a/src/OSSupport/Queue.h b/src/OSSupport/Queue.h
index cde26e415..6c3d58295 100644
--- a/src/OSSupport/Queue.h
+++ b/src/OSSupport/Queue.h
@@ -19,123 +19,139 @@ implements the functions Delete() and Combine(). An example is given in
cQueueFuncs and is used as the default behavior.
*/
-// this empty struct allows for the callback functions to be inlined
+/// This empty struct allows for the callback functions to be inlined
template<class T>
struct cQueueFuncs
{
- public:
- // Called when an Item is deleted form the queue without being returned
- static void Delete(T) {};
- // Called when an Item is inserted with EnqueueItemIfNotPresent and
- // there is another equal value already inserted
- static void Combine(T& a_existing, const T& a_new) {};
+public:
+
+ /// Called when an Item is deleted from the queue without being returned
+ static void Delete(T) {};
+
+ /// Called when an Item is inserted with EnqueueItemIfNotPresent and there is another equal value already inserted
+ static void Combine(T & a_existing, const T & a_new) {};
};
-template<class ItemType, class Funcs = cQueueFuncs<ItemType> >
+
+
+
+
+template <class ItemType, class Funcs = cQueueFuncs<ItemType> >
class cQueue
{
-// internal typedef for a List of Items
-typedef typename std::list<ItemType> ListType;
-// magic typedef to persuade clang that the iterator is a type
-typedef typename ListType::iterator iterator;
+ // The actual storage type for the queue
+ typedef typename std::list<ItemType> QueueType;
+
+ // Make iterator an alias for the QueueType's iterator
+ typedef typename QueueType::iterator iterator;
+
public:
cQueue() {}
~cQueue() {}
- // Enqueues an item to the queue, may block if other threads are accessing
- // the queue.
- void EnqueueItem(ItemType a_item)
+
+ /// Enqueues an item to the queue, may block if other threads are accessing the queue.
+ void EnqueueItem(ItemType a_Item)
{
cCSLock Lock(m_CS);
- m_contents.push_back(a_item);
+ m_Contents.push_back(a_Item);
m_evtAdded.Set();
}
- // Enqueues an item to the queue if not already present as determined with
- // operator ==. Will block other threads from accessing the queue.
- void EnqueueItemIfNotPresent(ItemType a_item)
+
+ /// Enqueues an item in the queue if not already present (as determined by operator ==). Blocks other threads from accessing the queue.
+ void EnqueueItemIfNotPresent(ItemType a_Item)
{
cCSLock Lock(m_CS);
- for (iterator itr = m_contents.begin(); itr != m_contents.end(); ++itr)
+ for (iterator itr = m_Contents.begin(); itr != m_Contents.end(); ++itr)
{
- if((*itr) == a_item) {
- Funcs funcTable;
- funcTable.Combine(*itr,a_item);
+ if ((*itr) == a_Item)
+ {
+ Funcs::Combine(*itr, a_Item);
return;
}
}
- m_contents.push_back(a_item);
+ m_Contents.push_back(a_Item);
m_evtAdded.Set();
}
- // Dequeues an Item from the queue if any are present. Returns true if
- // successful. Value of item is undefined if Dequeuing was unsuccessful.
- bool TryDequeueItem(ItemType& item)
+
+ /// Dequeues an item from the queue if any are present.
+ /// Returns true if successful. Value of item is undefined if dequeuing was unsuccessful.
+ bool TryDequeueItem(ItemType & item)
{
cCSLock Lock(m_CS);
- if (m_contents.size() == 0)
+ if (m_Contents.size() == 0)
{
return false;
}
- item = m_contents.front();
- m_contents.pop_front();
+ item = m_Contents.front();
+ m_Contents.pop_front();
m_evtRemoved.Set();
return true;
}
- // Dequeues an Item from the Queue, blocking until an Item is Available.
- ItemType DequeueItem()
+
+ /// Dequeues an item from the queue, blocking until an item is available.
+ ItemType DequeueItem(void)
{
cCSLock Lock(m_CS);
- while (m_contents.size() == 0)
+ while (m_Contents.size() == 0)
{
- cCSUnlock Unlock(m_CS);
+ cCSUnlock Unlock(Lock);
m_evtAdded.Wait();
}
- ItemType item = m_contents.front();
- m_contents.pop_front();
+ ItemType item = m_Contents.front();
+ m_Contents.pop_front();
m_evtRemoved.Set();
return item;
}
- // Blocks Until the queue is Empty, Has a slight race condition which may
- // cause it to miss the queue being empty.
- void BlockTillEmpty() {
- // There is a very slight race condition here if the load completes between the check
- // and the wait.
- while(!(Size() == 0)){m_evtRemoved.Wait();}
+
+ /// Blocks until the queue is empty.
+ void BlockTillEmpty(void)
+ {
+ cCSLock Lock(m_CS);
+ while (!m_Contents.empty())
+ {
+ cCSUnlock Unlock(Lock);
+ m_evtRemoved.Wait();
+ }
}
- // Removes all Items from the Queue, calling Delete on each of them.
- // can all be inlined when delete is a noop
- void Clear()
+
+ /// Removes all Items from the Queue, calling Delete on each of them.
+ void Clear(void)
{
cCSLock Lock(m_CS);
- Funcs funcTable;
- while (!m_contents.empty())
+ while (!m_Contents.empty())
{
- funcTable.Delete(m_contents.front());
- m_contents.pop_front();
+ Funcs::Delete(m_Contents.front());
+ m_Contents.pop_front();
}
}
- // Returns the Size at time of being called
- // Do not use to detirmine weather to call DequeueItem, use TryDequeue instead
- size_t Size()
+
+ /// Returns the size at time of being called.
+ /// Do not use to determine whether to call DequeueItem(), use TryDequeueItem() instead
+ size_t Size(void)
{
cCSLock Lock(m_CS);
- return m_contents.size();
+ return m_Contents.size();
}
- // Removes an Item from the queue
- bool Remove(ItemType a_item)
+
+ /// Removes the item from the queue. If there are multiple such items, only the first one is removed.
+ /// Returns true if the item has been removed, false if no such item found.
+ bool Remove(ItemType a_Item)
{
cCSLock Lock(m_CS);
- for (iterator itr = m_contents.begin(); itr != m_contents.end(); ++itr)
+ for (iterator itr = m_Contents.begin(); itr != m_Contents.end(); ++itr)
{
- if((*itr) == a_item) {
- m_contents.erase(itr);
+ if ((*itr) == a_Item)
+ {
+ m_Contents.erase(itr);
m_evtRemoved.Set();
return true;
}
@@ -144,8 +160,19 @@ public:
}
private:
- ListType m_contents;
+ /// The contents of the queue
+ QueueType m_Contents;
+
+ /// Mutex that protects access to the queue contents
cCriticalSection m_CS;
+
+ /// Event that is signalled when an item is added
cEvent m_evtAdded;
+
+ /// Event that is signalled when an item is removed (both dequeued or erased)
cEvent m_evtRemoved;
};
+
+
+
+