GCC Code Coverage Report
Directory: ./ Exec Total Coverage
File: lib/libc/db/hash/hash_func.c Lines: 0 14 0.0 %
Date: 2017-11-13 Branches: 0 13 0.0 %

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/*	$OpenBSD: hash_func.c,v 1.11 2016/05/29 20:47:49 guenther Exp $	*/
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/*-
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 * Copyright (c) 1990, 1993
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 *	The Regents of the University of California.  All rights reserved.
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 *
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 * This code is derived from software contributed to Berkeley by
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 * Margo Seltzer.
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 *
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 * Redistribution and use in source and binary forms, with or without
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 * modification, are permitted provided that the following conditions
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 * are met:
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 * 1. Redistributions of source code must retain the above copyright
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 *    notice, this list of conditions and the following disclaimer.
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 * 2. Redistributions in binary form must reproduce the above copyright
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 *    notice, this list of conditions and the following disclaimer in the
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 *    documentation and/or other materials provided with the distribution.
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 * 3. Neither the name of the University nor the names of its contributors
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 *    may be used to endorse or promote products derived from this software
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 *    without specific prior written permission.
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 *
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 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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 * SUCH DAMAGE.
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 */
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#include <sys/types.h>
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#include <db.h>
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/* Chris Torek's hash function. */
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u_int32_t
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__default_hash(const void *key, size_t len)
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{
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	u_int32_t h, loop;
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	u_int8_t *k;
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#define HASH4a   h = (h << 5) - h + *k++;
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#define HASH4b   h = (h << 5) + h + *k++;
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#define HASH4 HASH4b
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	h = 0;
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	k = (u_int8_t *)key;
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	if (len > 0) {
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		loop = (len + 8 - 1) >> 3;
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		switch (len & (8 - 1)) {
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		case 0:
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			do {	/* All fall throughs */
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				HASH4;
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		case 7:
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				HASH4;
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		case 6:
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				HASH4;
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		case 5:
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				HASH4;
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		case 4:
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				HASH4;
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		case 3:
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				HASH4;
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		case 2:
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				HASH4;
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		case 1:
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				HASH4;
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			} while (--loop);
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		}
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	}
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	return (h);
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}