- Add swap() method signature to SchedulableQueue

- Export swap() to SWIG
- Add sort function (just its documentation, actually, implementation will
follow) to Policy.py


git-svn-id: svn://svn.gna.org/svn/sgpemv2/trunk@385 3ecf2c5c-341e-0410-92b4-d18e462d057c

src/backend/pyloader/Policy.py

@@ -1,5 +1,22 @@
 from Abstract import *
 
+## @brief this function implements a quicksort in place
+# using the SchedulableQueue methods
+#
+# The compare parameter should be a user defined function
+# name returning either True or False, defined like:
+# @code
+# def compare(SchedulableA,SchedulableB):
+#     return SchedulableA.someProperty() < SchedulableB.someProperty()
+# @endcode
+#
+# @param queue The SchedulableQueue to be sorted in place
+# @param cmp The binary function to use to compare elements
+# @returns None
+def sort(queue, cmp):
+    pass
+    
+
 class Policy:
     ## @var Avoid instantiation of an abstract class
     __metaclass__ = Metaclass

src/backend/schedulable_list.hh

@@ -50,6 +50,22 @@ namespace sgpem
 	SchedulableStatus*		 		get_item_at(const uint&);
 	const SchedulableStatus* 		get_item_at(const uint&) const;
 	void							clear();
+
+	/** \brief This method swaps the element at positionA with
+	 * the one at positionB.
+	 *
+	 * At the present moment, this function shouldn't throw any 
+	 * exception, but just do nothing when the parameters don't
+	 * make sense (e.g. positionB > this.size()).
+	 * However, it should work the same either if positionA is greater
+	 * than or less than positionB.
+	 * In the future, this method could throw an OutOfRange exception.
+	 *
+	 * \param positionA The position of the first element to swap
+	 * \param positionB The position of the second element to swap
+	 */
+	void swap(unsigned int positionA, unsigned int positionB) throw() {}
+
     private:
 	std::list<SchedulableStatus>  _list;
     };

src/backend/sgpem.i

@@ -132,6 +132,7 @@ namespace sgpem {
 	uint size() const;
 	SchedulableStatus* get_item_at(const uint&);
 	const SchedulableStatus* get_item_at(const uint&) const;
+	void swap(unsigned int positionA, unsigned int positionB) throw();
 	
     private:
 	// Avoid instantiation and copy