Initial import of the CDE 2.1.30 sources from the Open Group.

cde/lib/tt/mini_isam/iskeycalc.c

@@ -0,0 +1,54 @@
+/*%%  (c) Copyright 1993, 1994 Hewlett-Packard Company			 */
+/*%%  (c) Copyright 1993, 1994 International Business Machines Corp.	 */
+/*%%  (c) Copyright 1993, 1994 Sun Microsystems, Inc.			 */
+/*%%  (c) Copyright 1993, 1994 Novell, Inc. 				 */
+/*%%  $XConsortium: iskeycalc.c /main/3 1995/10/23 11:41:29 rswiston $ 			 				 */
+#ifndef lint
+static char sccsid[] = "@(#)iskeycalc.c 1.3 89/07/17 Copyr 1988 Sun Micro";
+#endif
+/*
+ * Copyright (c) 1988 by Sun Microsystems, Inc.
+ */
+
+/*
+ * iskeycalc.c
+ *
+ * Description:
+ *	Key related calculation functions
+ */
+
+#include "isam_impl.h"
+
+
+/* getkeysperleaf() - Calculate number of keys per leaf node */
+int 
+getkeysperleaf (keylen)
+    int		keylen;
+{
+    int 	n;
+
+    n = ((ISPAGESIZE - BT_KEYS_OFF) / keylen);
+
+    return (le_odd (n));		     /* n or n-1 */
+}
+
+/* getkeyspernode() - Calculate number of keys per non-leaf node */
+int 
+getkeyspernode (keylen)
+    int		keylen;
+{
+    int 	n;
+
+    n = ((ISPAGESIZE - BT_KEYS_OFF) / (keylen + BLKNOSIZE));
+
+    return (le_odd (n));		     /* n or n-1 */
+}
+
+
+/* le_odd(n) - Get next lower or equal odd number */
+int 
+le_odd(n)
+    int		n;
+{
+    return ((n - 1) | 1);
+}