From a7b23a8f11b2e1f2ef333d2ed95d1c972acad12f Mon Sep 17 00:00:00 2001 From: Thomas Fitzsimmons Date: Thu, 20 Jun 2002 19:51:40 +0000 Subject: * Makefile.am (LIB_OBJECTLISTS): Add libc/search/objectlist.awk.in. * libc/Makefile.am (SUBDIRS): Add search. (SUBLIBS): Add search/libsearch.la. * libc/configure.in (AC_OUTPUT): Add search/Makefile. * libc/search: New directory. * libc/search/Makefile.am: New file. * libc/search/extern.h: New file. * libc/search/hash.c: New file. * libc/search/hash.h: New file. * libc/search/hash_bigkey.c: New file. * libc/search/hash_buf.c: New file. * libc/search/hash_func.c: New file. * libc/search/hash_log2.c: New file. * libc/search/hash_page.c: New file. * libc/search/hcreate.3: New file. * libc/search/hcreate.c: New file. * libc/search/hcreate.c~: New file. * libc/search/hcreate_r.c: New file. * libc/search/ndbm.c: New file. * libc/search/page.h: New file. * libc/search/tdelete.c: New file. * libc/search/tdestroy.c: New file. * libc/search/tfind.c: New file. * libc/search/tsearch.3: New file. * libc/search/tsearch.c: New file. * libc/search/twalk.c: New file. * libc/include/db.h: New file. * libc/include/ndbm.h: New file. * libc/include/search.h: New file. * libc/include/sys/queue.h: New file. * libc/include/sys/cdefs.h: New file. * libc/include/sys/param.h [__IEEE_LITTLE_ENDIAN,__IEEE_BIG_ENDIAN]: Set BYTE_ORDER to LITTLE_ENDIAN or BIG_ENDIAN. * libc/include/sys/errno.h (EFTYPE): New macro. * libc/search/bsearch.c: Move from libc/stdlib. * libc/search/qsort.c: Likewise. * libc/stdlib/Makefile.am (LIB_SOURCES): Remove bsearch.c and qsort.c. (CHEWOUT_FILES): Remove bsearch.def and qsort.def. * libc/stdlib/stdlib.tex: Remove references to bsearch and qsort. --- newlib/libc/search/hash_func.c | 212 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 212 insertions(+) create mode 100644 newlib/libc/search/hash_func.c (limited to 'newlib/libc/search/hash_func.c') diff --git a/newlib/libc/search/hash_func.c b/newlib/libc/search/hash_func.c new file mode 100644 index 000000000..deeb21e60 --- /dev/null +++ b/newlib/libc/search/hash_func.c @@ -0,0 +1,212 @@ +/*- + * 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. All advertising materials mentioning features or use of this software + * must display the following acknowledgement: + * This product includes software developed by the University of + * California, Berkeley and its contributors. + * 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 +#include + +#include +#include "hash.h" +#include "page.h" +#include "extern.h" + +static __uint32_t hash1(const void *, size_t); +static __uint32_t hash2(const void *, size_t); +static __uint32_t hash3(const void *, size_t); +static __uint32_t hash4(const void *, size_t); + +/* Global default hash function */ +__uint32_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 __uint32_t +hash1(keyarg, len) + const void *keyarg; + size_t len; +{ + const u_char *key; + __uint32_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 __uint32_t +hash2(keyarg, len) + const void *keyarg; + size_t len; +{ + const u_char *e, *key; + __uint32_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 __uint32_t +hash3(keyarg, len) + const void *keyarg; + size_t len; +{ + const u_char *key; + size_t loop; + __uint32_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 __uint32_t +hash4(keyarg, len) + const void *keyarg; + size_t len; +{ + const u_char *key; + size_t loop; + __uint32_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); +} -- cgit v1.2.3