From 38e876d964346d3e4b88c52732b7ce5966d796a5 Mon Sep 17 00:00:00 2001 From: Dimitri Sokolyuk Date: Thu, 1 Nov 2018 13:35:40 +0100 Subject: import original 1.85 implementation from openbsd libc --- _db1.85/hash/hash_log2.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) create mode 100644 _db1.85/hash/hash_log2.c (limited to '_db1.85/hash/hash_log2.c') diff --git a/_db1.85/hash/hash_log2.c b/_db1.85/hash/hash_log2.c new file mode 100644 index 0000000..533e2cd --- /dev/null +++ b/_db1.85/hash/hash_log2.c @@ -0,0 +1,48 @@ +/* $OpenBSD: hash_log2.c,v 1.8 2005/08/05 13:03:00 espie Exp $ */ + +/*- + * Copyright (c) 1990, 1993, 1994 + * The Regents of the University of California. All rights reserved. + * + * This code is derived from software contributed to Berkeley by + * Margo Seltzer. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * 3. Neither the name of the University nor the names of its contributors + * may be used to endorse or promote products derived from this software + * without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND + * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE + * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS + * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT + * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY + * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF + * SUCH DAMAGE. + */ + +#include +#include "hash.h" +#include "page.h" +#include "extern.h" + +u_int32_t +__log2(u_int32_t num) +{ + u_int32_t i, limit; + + limit = 1; + for (i = 0; limit < num; limit = limit << 1, i++); + return (i); +} -- cgit v1.2.3