X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;ds=sidebyside;f=src%2Flibpspp%2Farray.c;h=f375f83dfa9851bdb6208d0875d2356031c7501f;hb=d08af71f38b751323cc9506631bf9ce71070a4ae;hp=8af5d8fecec7ce1ccd5891cae5de6364ea3f8c89;hpb=19f2bec879b9b03eebc8b32b67332c9ea586188d;p=pspp-builds.git

diff --git a/src/libpspp/array.c b/src/libpspp/array.c
index 8af5d8fe..f375f83d 100644
--- a/src/libpspp/array.c
+++ b/src/libpspp/array.c
@@ -415,6 +415,36 @@ move_element (void *array_, size_t count, size_t size,
     }
 }
 
+/* Moves N elements in ARRAY starting at OLD_IDX, which consists
+   of COUNT elements of SIZE bytes each, so that they now start
+   at NEW_IDX, shifting around other elements as needed. */
+void
+move_range (void *array_, size_t count, size_t size,
+            size_t old_idx, size_t new_idx, size_t n)
+{
+  assert (array_ != NULL || count == 0);
+  assert (n <= count);
+  assert (old_idx + n <= count);
+  assert (new_idx + n <= count);
+  
+  if (old_idx != new_idx && n > 0) 
+    {
+      char *array = array_;
+      char *range = xmalloc (size * n);
+      char *new = array + new_idx * size;
+      char *old = array + old_idx * size;
+
+      memcpy (range, old, size * n);
+      if (new < old)
+        memmove (new + size * n, new, (old_idx - new_idx) * size);
+      else
+        memmove (old, old + size * n, (new_idx - old_idx) * size);
+      memcpy (new, range, size * n);
+
+      free (range);
+    }
+}
+
 /* A predicate and its auxiliary data. */
 struct pred_aux 
   {