Merged with trunk R1283.

[ardour.git] / libs / pbd / undo.cc

diff --git a/libs/pbd/undo.cc b/libs/pbd/undo.cc
index 277b83bfced06c3897421356ba6b5b89c719c3d8..4719d0968eb07cc70301f27ec50f07f291964089 100644 (file)
--- a/libs/pbd/undo.cc
+++ b/libs/pbd/undo.cc
@@ -236,13 +236,31 @@ UndoHistory::clear ()
        Changed (); /* EMIT SIGNAL */
 }
 
-XMLNode & UndoHistory::get_state()
+XMLNode& 
+UndoHistory::get_state (uint32_t depth)
 {
     XMLNode *node = new XMLNode ("UndoHistory");
 
-    list<UndoTransaction*>::iterator it;
-    for (it = UndoList.begin(); it != UndoList.end(); it++) {
-           node->add_child_nocopy((*it)->get_state());
+    if (depth == 0) {
+           /* everything */
+
+           for (list<UndoTransaction*>::iterator it = UndoList.begin(); it != UndoList.end(); ++it) {
+                   node->add_child_nocopy((*it)->get_state());
+           }
+           
+    } else {
+
+           /* just the last "depth" transactions */
+
+           list<UndoTransaction*> in_order;
+
+           for (list<UndoTransaction*>::reverse_iterator it = UndoList.rbegin(); it != UndoList.rend() && depth; ++it, depth--) {
+                   in_order.push_front (*it);
+           }
+
+           for (list<UndoTransaction*>::iterator it = in_order.begin(); it != in_order.end(); it++) {
+                   node->add_child_nocopy((*it)->get_state());
+           }
     }
 
     return *node;