libsaria: Convert the idle queue to use the new list class

- The erase() function returns the previous item
- Implement a push_front() function
- Implement a pop_front() function

Signed-off-by: Bryan Schumaker <bjschuma@gmail.com>

include/libsaria/list.h

@@ -11,17 +11,17 @@ namespace libsaria
 	class ListItem {
 		friend class List<T>;
 		private:
-			ListItem *prev;
-			ListItem *next;
+			ListItem *prev_item;
+			ListItem *next_item;
 			List<T>  *list;
 			T value;
 
 		public:
 			ListItem();
-			ListItem(T, List<T> *);
+			ListItem(T, List<T> *, ListItem<T> *, ListItem<T> *);
 			~ListItem();
 			T &get_value();
-			ListItem<T> *get_next();
+			ListItem<T> *next();
 	};
 
 	template <class T>
@@ -35,8 +35,11 @@ namespace libsaria
 			List(const List<T> &);
 			~List();
 
+			ListItem<T> *push_front(T);
 			ListItem<T> *push_back(T);
-			void erase(ListItem<T> *);
+			T pop_front();
+
+			ListItem<T> *erase(ListItem<T> *);
 			unsigned int size();
 
 			ListItem<T> *first();

libsaria/idle/idle.cpp

@@ -1,12 +1,10 @@
 // Copyright (c) 2011 Bryan Schumaker.
 #include <libsaria/idle.h>
+#include <libsaria/list.h>
 #include <libsaria/print.h>
 
-#include <list>
-using namespace std;
-
 static bool enabled = false;
-static list<IdleTask *> idle_queue;
+static libsaria::List<IdleTask *> idle_queue;
 static float queued = 0.0;
 static float serviced = 0.0;
 
@@ -36,8 +34,7 @@ namespace libsaria
 		IdleTask *task;
 		if (size() == 0)
 			return;
-		task = idle_queue.front();
-		idle_queue.pop_front();
+		task = idle_queue.pop_front();
 		do_task(task);
 		if (size() == 0) {
 			queued = 0.0;
@@ -67,12 +64,10 @@ namespace libsaria
 
 	void idle::cancel_all(void *data)
 	{
-		list<IdleTask *>::iterator it;
-		for (it = idle_queue.begin(); it != idle_queue.end(); it++) {
-			if ((*it)->should_cancel(data)) {
+		ListItem<IdleTask *> *it;
+		for (it = idle_queue.first(); it != idle_queue.last(); it = it->next()) {
+			if (it->get_value()->should_cancel(data))
 				it = idle_queue.erase(it);
-				it--;
-			}
 		}
 	}
 

libsaria/list/list.cpp

@@ -32,35 +32,52 @@ namespace libsaria
 	List<T>::~List()
 	{
 		while (count > 0)
-			erase(head.next);
+			erase(head.next_item);
 	}
 
 	template <class T>
-	ListItem<T> *List<T>::push_back(T item)
+	ListItem<T> *List<T>::push_front(T item)
 	{
-		ListItem<T> *node = new ListItem<T>(item, this);
-		ListItem<T> *last = head.prev;
-
-		last->next = node;
-		node->prev = last;
-		node->next = &head;
-		head.prev  = node;
-
+		ListItem<T> *node;
+		node = new ListItem<T>(item, this, &head, first());
 		count++;
 		return node;
 	}
 
 	template <class T>
-	void List<T>::erase(ListItem<T> *node)
+	ListItem<T> *List<T>::push_back(T item)
 	{
-		ListItem<T> *prev = node->prev;
-		ListItem<T> *next = node->next;
+		ListItem<T> *node;
+		node = new ListItem<T>(item, this, head.prev_item, &head);
+		count++;
+		return node;
+	}
 
-		prev->next = next;
-		next->prev = prev;
+	template <class T>
+	T List<T>::pop_front()
+	{
+		T item;
+		if (count == 0)
+			item = head.value;
+		else {
+			item = first()->value;
+			erase(first());
+		}
+		return item;
+	}
 
+	template <class T>
+	ListItem<T> *List<T>::erase(ListItem<T> *node)
+	{
+		ListItem<T> *prev = node->prev_item;
+		ListItem<T> *next = node->next_item;
+
+		prev->next_item = next;
+		next->prev_item = prev;
 		count--;
 		delete node;
+
+		return prev;
 	}
 
 	template <class T>
@@ -72,7 +89,7 @@ namespace libsaria
 	template <class T>
 	ListItem<T> *List<T>::first()
 	{
-		return head.next;
+		return head.next_item;
 	}
 
 	template <class T>
@@ -84,7 +101,7 @@ namespace libsaria
 	template <class T>
 	void List<T>::for_each_item(void (*func)(T &, void *), void *data)
 	{
-		for (ListItem<T> *it = first(); it != last(); it = it->get_next())
+		for (ListItem<T> *it = first(); it != last(); it = it->next())
 			func(it->value, data);
 	}
 
@@ -92,9 +109,9 @@ namespace libsaria
 	ListItem<T> *List<T>::find_item(bool (*func)(T &, void *), void *data)
 	{
 		ListItem<T> *it;
-		for (it = first(); it != last; it = it->get_next()) {
+		for (it = first(); it != last(); it = it->next()) {
 			if (func(it->value, data))
-				return item;
+				return it;
 		}
 		return NULL;
 	}

libsaria/list/node.cpp

@@ -11,15 +11,20 @@ namespace libsaria
 	template <class T>
 	ListItem<T>::ListItem()
 	{
-		prev = this;
-		next = this;
+		prev_item = this;
+		next_item = this;
 	}
 
 	template <class T>
-	ListItem<T>::ListItem(T val, List<T> *lst)
+	ListItem<T>::ListItem(T val, List<T> *lst, ListItem<T> *a, ListItem<T> *b)
 	{
 		list = lst;
 		value = val;
+
+		a->next_item = this;
+		prev_item = a;
+		next_item = b;
+		b->prev_item = this;
 	}
 
 	template <class T>
@@ -34,9 +39,9 @@ namespace libsaria
 	}
 
 	template <class T>
-	ListItem<T> *ListItem<T>::get_next()
+	ListItem<T> *ListItem<T>::next()
 	{
-		return next;
+		return next_item;
 	}
 
 }