[Aptitude-svn-commit] r4103 - in branches/aptitude-0.3/aptitude: . src/generic/problemresolver

[Daniel Burrows]

Author: dburrows
Date: Sat Sep 17 04:09:00 2005
New Revision: 4103

Modified:
   branches/aptitude-0.3/aptitude/ChangeLog
   branches/aptitude-0.3/aptitude/src/generic/problemresolver/conflictset.h
Log:
Handle the case of an empty right branch.

Modified: branches/aptitude-0.3/aptitude/ChangeLog
==============================================================================
--- branches/aptitude-0.3/aptitude/ChangeLog	(original)
+++ branches/aptitude-0.3/aptitude/ChangeLog	Sat Sep 17 04:09:00 2005
@@ -1,5 +1,13 @@
 2005-09-16  Daniel Burrows  <dburrows at debian.org>
 
+	* src/generic/problemresolver/conflictset.h:
+
+	  Properly handle the case of an empty right branch by just
+	  setting right_offset to one past the left branch.  This is
+	  exactly correct, although it has the effect of causing the tree
+	  to overlap itself (if you work it out, though, this is exactly
+	  what's desired anyway).
+
 	* tests/test_resolver.cc, src/generic/problemresolver/conflictset.h, src/generic/problemresolver/problemresolver.h:
 
 	  Add an experimental conflict set optimized under some

Modified: branches/aptitude-0.3/aptitude/src/generic/problemresolver/conflictset.h
==============================================================================
--- branches/aptitude-0.3/aptitude/src/generic/problemresolver/conflictset.h	(original)
+++ branches/aptitude-0.3/aptitude/src/generic/problemresolver/conflictset.h	Sat Sep 17 04:09:00 2005
@@ -142,7 +142,9 @@
   struct node
   {
     /** The number of elements to move forward in the array to reach
-     *	the right child of this node.  If 0, there is no right child.
+     *	the right child of this node.  If there is no right child,
+     *	this is the offset to the end of the left child (which is by
+     *	definition where the search goes if there is no right child).
      */
     unsigned int right_offset;
 
@@ -267,12 +269,10 @@
 					       best_split->first,
 					       best_split->second));
 
+    typename std::vector<node>::size_type right_elt = tree.size();
+    tree[curr_elt].right_offset = right_elt - curr_elt;
     if(!right_children.empty())
-      {
-	typename std::vector<node>::size_type right_elt = tree.size();
-	tree[curr_elt].right_offset = right_elt - curr_elt;
-	build_tree(right_children, env);
-      }
+      build_tree(right_children, env);
   }
 
   static void dump(std::ostream &out, const action &act)
@@ -320,8 +320,10 @@
 	    out << ")" << std::endl;
 
 	    dump(out, elt + 1, "L: ", indent+4);
-	    if(elt->right_offset > 0)
-	      dump(out, elt + elt->right_offset ,"R: ", indent+4);
+	    // FIXME: whether this is entirely correct is a matter of
+	    // opinion; it may do odd things when the tree overlaps
+	    // itself.
+	    dump(out, elt + elt->right_offset ,"R: ", indent+4);
 	  }
       }
   }
@@ -379,10 +381,8 @@
 
 	if(matches)
 	  ++i;
-	else if(i->right_offset > 0)
-	  i += i->right_offset;
 	else
-	  ++i;
+	  i += i->right_offset;
       }
 
     return entries.end();