Add ability for reverse iteration to tower code, and corresponding

[pspp-builds.git] / src / libpspp / tower.h

diff --git a/src/libpspp/tower.h b/src/libpspp/tower.h
index 5a4c08e204f714aa334c054a73db8867518594f3..674564c685464ccbf6f8934e22a8ebf876add739 100644 (file)
--- a/src/libpspp/tower.h
+++ b/src/libpspp/tower.h
@@ -97,7 +97,10 @@ struct tower_node *tower_lookup (const struct tower *,
                                  unsigned long int level,
                                  unsigned long int *node_start);
 struct tower_node *tower_first (const struct tower *);
+struct tower_node *tower_last (const struct tower *);
 struct tower_node *tower_next (const struct tower *,
                                const struct tower_node *);
+struct tower_node *tower_prev (const struct tower *,
+                               const struct tower_node *);
 
 #endif /* libpspp/tower.h */