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db/hash/FreeBSD/hash_func.c Libc-1725.40.4 /dev/null
--- Libc/Libc-1725.40.4/db/hash/FreeBSD/hash_func.c
+++ /dev/null
@@ -1,202 +0,0 @@
-/*-
- * Copyright (c) 1990, 1993
- *	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.
- * 4. 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.
- */
-
-#if defined(LIBC_SCCS) && !defined(lint)
-static char sccsid[] = "@(#)hash_func.c	8.2 (Berkeley) 2/21/94";
-#endif /* LIBC_SCCS and not lint */
-#include <sys/cdefs.h>
-__FBSDID("$FreeBSD: src/lib/libc/db/hash/hash_func.c,v 1.6 2007/01/09 00:27:50 imp Exp $");
-
-#include <sys/types.h>
-
-#include <db.h>
-#include "hash.h"
-#include "page.h"
-#include "hash_extern.h"
-
-static u_int32_t hash1(const void *, size_t) __unused;
-static u_int32_t hash2(const void *, size_t) __unused;
-static u_int32_t hash3(const void *, size_t) __unused;
-static u_int32_t hash4(const void *, size_t);
-
-/* Global default hash function */
-u_int32_t (*__default_hash)(const void *, size_t) = hash4;
-
-/*
- * HASH FUNCTIONS
- *
- * Assume that we've already split the bucket to which this key hashes,
- * calculate that bucket, and check that in fact we did already split it.
- *
- * This came from ejb's hsearch.
- */
-
-#define PRIME1		37
-#define PRIME2		1048583
-
-static u_int32_t
-hash1(const void *keyarg, size_t len)
-{
-	const u_char *key;
-	u_int32_t h;
-
-	/* Convert string to integer */
-	for (key = keyarg, h = 0; len--;)
-		h = h * PRIME1 ^ (*key++ - ' ');
-	h %= PRIME2;
-	return (h);
-}
-
-/*
- * Phong's linear congruential hash
- */
-#define dcharhash(h, c)	((h) = 0x63c63cd9*(h) + 0x9c39c33d + (c))
-
-static u_int32_t
-hash2(const void *keyarg, size_t len)
-{
-	const u_char *e, *key;
-	u_int32_t h;
-	u_char c;
-
-	key = keyarg;
-	e = key + len;
-	for (h = 0; key != e;) {
-		c = *key++;
-		if (!c && key > e)
-			break;
-		dcharhash(h, c);
-	}
-	return (h);
-}
-
-/*
- * This is INCREDIBLY ugly, but fast.  We break the string up into 8 byte
- * units.  On the first time through the loop we get the "leftover bytes"
- * (strlen % 8).  On every other iteration, we perform 8 HASHC's so we handle
- * all 8 bytes.  Essentially, this saves us 7 cmp & branch instructions.  If
- * this routine is heavily used enough, it's worth the ugly coding.
- *
- * OZ's original sdbm hash
- */
-static u_int32_t
-hash3(const void *keyarg, size_t len)
-{
-	const u_char *key;
-	size_t loop;
-	u_int32_t h;
-
-#define HASHC   h = *key++ + 65599 * h
-
-	h = 0;
-	key = keyarg;
-	if (len > 0) {
-		loop = (len + 8 - 1) >> 3;
-
-		switch (len & (8 - 1)) {
-		case 0:
-			do {
-				HASHC;
-				/* FALLTHROUGH */
-		case 7:
-				HASHC;
-				/* FALLTHROUGH */
-		case 6:
-				HASHC;
-				/* FALLTHROUGH */
-		case 5:
-				HASHC;
-				/* FALLTHROUGH */
-		case 4:
-				HASHC;
-				/* FALLTHROUGH */
-		case 3:
-				HASHC;
-				/* FALLTHROUGH */
-		case 2:
-				HASHC;
-				/* FALLTHROUGH */
-		case 1:
-				HASHC;
-			} while (--loop);
-		}
-	}
-	return (h);
-}
-
-/* Hash function from Chris Torek. */
-static u_int32_t
-hash4(const void *keyarg, size_t len)
-{
-	const u_char *key;
-	size_t loop;
-	u_int32_t h;
-
-#define HASH4a   h = (h << 5) - h + *key++;
-#define HASH4b   h = (h << 5) + h + *key++;
-#define HASH4 HASH4b
-
-	h = 0;
-	key = keyarg;
-	if (len > 0) {
-		loop = (len + 8 - 1) >> 3;
-
-		switch (len & (8 - 1)) {
-		case 0:
-			do {
-				HASH4;
-				/* FALLTHROUGH */
-		case 7:
-				HASH4;
-				/* FALLTHROUGH */
-		case 6:
-				HASH4;
-				/* FALLTHROUGH */
-		case 5:
-				HASH4;
-				/* FALLTHROUGH */
-		case 4:
-				HASH4;
-				/* FALLTHROUGH */
-		case 3:
-				HASH4;
-				/* FALLTHROUGH */
-		case 2:
-				HASH4;
-				/* FALLTHROUGH */
-		case 1:
-				HASH4;
-			} while (--loop);
-		}
-	}
-	return (h);
-}