glibc/nis/nis_hash.c
Ulrich Drepper c207f23b0b Update.
* nscd/connections.c: Implement r/o sharing of nscd's cache with client
	processes via shared memory.
	* nscd/nscd-client.h: Likewise.
	* nscd/nscd.h: Likewise.
	* nscd/nscd_conf.c: Likewise.
	* nscd/nscd_getgr_r.c: Likewise.
	* nscd/nscd_getpw_r.c: Likewise.
	* nscd/nscd_gethst_r.c: Likewise.
	* nscd/nscd.conf: Add new config parameters.
	* nscd/Makefile (aux): Add nscd_helper.
	* nscd/nscd_helper.c: New file.
	* nscd/mem.c (gc): Indicate beginning and end of the gc cycle.

	* nscd/hstcache.c: Simplify a lot.  We cache only the request itself,
	no derived information.
	* connections.c (nscd_init): Fix bug in testing size of the persistent.

	* nis/Makefile (aux): Add nis_hash.
	* nis/nis_hash.c: New file.  Split out from nis_util.c.
	* nis/nis_util.c: Move __nis_hash code in separate file.

	* csu/tst-atomic.c: Improve atomic_increment_val test which would
	not have found a ppc bug.
2004-09-08 15:46:42 +00:00

77 lines
2.1 KiB
C

/* Copyright (c) 1997, 1998, 1999, 2004 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Thorsten Kukuk <kukuk@suse.de>, 1997.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <rpcsvc/nis.h>
/* This is from libc/db/hash/hash_func.c, hash3 is static there */
/*
* 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
*/
uint32_t
__nis_hash (const void *keyarg, register size_t len)
{
register const u_char *key;
register size_t loop;
register 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;
}