hmap: New function hmap_clear().

[pspp] / src / libpspp / hmap.c

diff --git a/src/libpspp/hmap.c b/src/libpspp/hmap.c
index 4c97e2359c922034cc8389344dc2a581227042d7..9050cc08f5571a6f2e8908201444d834a96a6398 100644 (file)
--- a/src/libpspp/hmap.c
+++ b/src/libpspp/hmap.c
@@ -1,5 +1,5 @@
 /* PSPP - a program for statistical analysis.
-   Copyright (C) 2008, 2009 Free Software Foundation, Inc.
+   Copyright (C) 2008, 2009, 2010 Free Software Foundation, Inc.
 
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -49,6 +49,18 @@ hmap_swap (struct hmap *a, struct hmap *b)
     b->buckets = &b->one;
 }
 
+/* Removes all of the elements from MAP, without destroying MAP itself and
+   without accessing the existing elements (if any). */
+void
+hmap_clear (struct hmap *map)
+{
+  size_t i;
+
+  for (i = 0; i <= map->mask; i++)
+    map->buckets[i] = NULL;
+  map->count = 0;
+}
+
 /* Frees the memory, if any, allocated by hash map MAP.  This has
    no effect on the actual data items in MAP, if any, because the
    client is responsible for allocating and freeing them.  It