Rename osx directory to src since it's now the official source base

src/tools/undo.cpp

@@ -0,0 +1,40 @@
+/*
+ *  undo.cpp
+ *  BoE
+ *
+ *  Created by Celtic Minstrel on 29/05/09.
+ *
+ */
+
+#include "undo.h"
+
+cUndoList::cUndoList(){
+	lastSave = cur = theList.begin();
+}
+
+size_t cUndoList::maxUndoSize = 0;
+
+//TODO: These functions should have error checking to ensure they do not access an out of bounds action
+void cUndoList::undo(){
+	(*cur)->undo();
+	cur--;
+}
+
+void cUndoList::redo(){
+	cur++;
+	(*cur)->redo();
+}
+
+void cUndoList::save(){
+	lastSave = cur;
+}
+
+void cUndoList::revert(){
+	while(cur != lastSave) undo();
+}
+
+void cUndoList::add(cAction* what){
+	theList.push_back(what);
+	num_actions++;
+	while(num_actions > maxUndoSize) theList.pop_front(), num_actions--;
+}