diff --git a/lib/libc/db/hash/extern.h b/lib/libc/db/hash/extern.h index d3850752ad3a..690219d30606 100644 --- a/lib/libc/db/hash/extern.h +++ b/lib/libc/db/hash/extern.h @@ -1,61 +1,61 @@ /*- * SPDX-License-Identifier: BSD-3-Clause * * Copyright (c) 1991, 1993, 1994 * The Regents of the University of California. All rights reserved. * * 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. */ BUFHEAD *__add_ovflpage(HTAB *, BUFHEAD *); int __addel(HTAB *, BUFHEAD *, const DBT *, const DBT *); int __big_delete(HTAB *, BUFHEAD *); int __big_insert(HTAB *, BUFHEAD *, const DBT *, const DBT *); int __big_keydata(HTAB *, BUFHEAD *, DBT *, DBT *, int); int __big_return(HTAB *, BUFHEAD *, int, DBT *, int); int __big_split(HTAB *, BUFHEAD *, BUFHEAD *, BUFHEAD *, int, u_int32_t, SPLIT_RETURN *); int __buf_free(HTAB *, int, int); void __buf_init(HTAB *, int); u_int32_t __call_hash(HTAB *, char *, int); int __delpair(HTAB *, BUFHEAD *, int); int __expand_table(HTAB *); int __find_bigpair(HTAB *, BUFHEAD *, int, char *, int); u_int16_t __find_last_page(HTAB *, BUFHEAD **); void __free_ovflpage(HTAB *, BUFHEAD *); BUFHEAD *__get_buf(HTAB *, u_int32_t, BUFHEAD *, int); int __get_page(HTAB *, char *, u_int32_t, int, int, int); int __ibitmap(HTAB *, int, int, int); u_int32_t __log2(u_int32_t); int __put_page(HTAB *, char *, u_int32_t, int, int); void __reclaim_buf(HTAB *, BUFHEAD *); int __split_page(HTAB *, u_int32_t, u_int32_t); /* Default hash routine. */ -extern u_int32_t (*__default_hash)(const void *, size_t); +u_int32_t __default_hash(const void *, size_t); #ifdef HASH_STATISTICS extern int hash_accesses, hash_collisions, hash_expansions, hash_overflows; #endif diff --git a/lib/libc/db/hash/hash_func.c b/lib/libc/db/hash/hash_func.c index 529180b7698d..29597a04d3c0 100644 --- a/lib/libc/db/hash/hash_func.c +++ b/lib/libc/db/hash/hash_func.c @@ -1,186 +1,81 @@ /*- * SPDX-License-Identifier: BSD-3-Clause * * 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. * 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 #include "hash.h" #include "page.h" #include "extern.h" -#ifdef notdef -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; -#endif -static u_int32_t hash4(const void *, size_t); - -/* Default hash function. */ -u_int32_t (*__default_hash)(const void *, size_t) = hash4; - -#ifdef notdef -/* - * 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. - * - * EJB's original hsearch hash. - */ -#define PRIME1 37 -#define PRIME2 1048583 - -u_int32_t -hash1(const void *key, size_t len) -{ - u_int32_t h; - u_int8_t *k; - - h = 0; - k = (u_int8_t *)key; - /* Convert string to integer */ - while (len--) - h = h * PRIME1 ^ (*k++ - ' '); - h %= PRIME2; - return (h); -} - -/* - * Phong Vo's linear congruential hash - */ -#define dcharhash(h, c) ((h) = 0x63c63cd9*(h) + 0x9c39c33d + (c)) - -u_int32_t -hash2(const void *key, size_t len) -{ - u_int32_t h; - u_int8_t *e, c, *k; - - k = (u_int8_t *)key; - e = k + len; - for (h = 0; k != e;) { - c = *k++; - if (!c && k > 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. - * - * Ozan Yigit's original sdbm hash. - */ -u_int32_t -hash3(const void *key, size_t len) -{ - u_int32_t n, loop; - u_int8_t *k; - -#define HASHC n = *k++ + 65599 * n - - n = 0; - k = (u_int8_t *)key; - if (len > 0) { - loop = (len + 8 - 1) >> 3; - - switch (len & (8 - 1)) { - case 0: - do { /* All fall throughs */ - HASHC; - case 7: - HASHC; - case 6: - HASHC; - case 5: - HASHC; - case 4: - HASHC; - case 3: - HASHC; - case 2: - HASHC; - case 1: - HASHC; - } while (--loop); - } - - } - return (n); -} -#endif /* notdef */ - /* Chris Torek's hash function. */ u_int32_t -hash4(const void *key, size_t len) +__default_hash(const void *key, size_t len) { u_int32_t h, loop; const u_int8_t *k; #define HASH4a h = (h << 5) - h + *k++; #define HASH4b h = (h << 5) + h + *k++; #define HASH4 HASH4b h = 0; k = key; if (len > 0) { loop = (len + 8 - 1) >> 3; switch (len & (8 - 1)) { case 0: do { /* All fall throughs */ HASH4; case 7: HASH4; case 6: HASH4; case 5: HASH4; case 4: HASH4; case 3: HASH4; case 2: HASH4; case 1: HASH4; } while (--loop); } } return (h); }