mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-20 11:11:24 +00:00
28993443b4
Although this file has historically been used as a dumping ground for random functions, nowadays it only contains functions related to copying bits {from,to} userspace and hash table utility functions. Behold, subr_uio.c and subr_hash.c.
133 lines
4.2 KiB
C
133 lines
4.2 KiB
C
/*-
|
|
* Copyright (c) 1982, 1986, 1991, 1993
|
|
* The Regents of the University of California. All rights reserved.
|
|
* (c) UNIX System Laboratories, Inc.
|
|
* All or some portions of this file are derived from material licensed
|
|
* to the University of California by American Telephone and Telegraph
|
|
* Co. or Unix System Laboratories, Inc. and are reproduced herein with
|
|
* the permission of UNIX System Laboratories, Inc.
|
|
*
|
|
* 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.
|
|
*
|
|
* @(#)kern_subr.c 8.3 (Berkeley) 1/21/94
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include <sys/param.h>
|
|
#include <sys/systm.h>
|
|
#include <sys/malloc.h>
|
|
|
|
/*
|
|
* General routine to allocate a hash table with control of memory flags.
|
|
*/
|
|
void *
|
|
hashinit_flags(int elements, struct malloc_type *type, u_long *hashmask,
|
|
int flags)
|
|
{
|
|
long hashsize;
|
|
LIST_HEAD(generic, generic) *hashtbl;
|
|
int i;
|
|
|
|
if (elements <= 0)
|
|
panic("hashinit: bad elements");
|
|
|
|
/* Exactly one of HASH_WAITOK and HASH_NOWAIT must be set. */
|
|
KASSERT((flags & HASH_WAITOK) ^ (flags & HASH_NOWAIT),
|
|
("Bad flags (0x%x) passed to hashinit_flags", flags));
|
|
|
|
for (hashsize = 1; hashsize <= elements; hashsize <<= 1)
|
|
continue;
|
|
hashsize >>= 1;
|
|
|
|
if (flags & HASH_NOWAIT)
|
|
hashtbl = malloc((u_long)hashsize * sizeof(*hashtbl),
|
|
type, M_NOWAIT);
|
|
else
|
|
hashtbl = malloc((u_long)hashsize * sizeof(*hashtbl),
|
|
type, M_WAITOK);
|
|
|
|
if (hashtbl != NULL) {
|
|
for (i = 0; i < hashsize; i++)
|
|
LIST_INIT(&hashtbl[i]);
|
|
*hashmask = hashsize - 1;
|
|
}
|
|
return (hashtbl);
|
|
}
|
|
|
|
/*
|
|
* Allocate and initialize a hash table with default flag: may sleep.
|
|
*/
|
|
void *
|
|
hashinit(int elements, struct malloc_type *type, u_long *hashmask)
|
|
{
|
|
|
|
return (hashinit_flags(elements, type, hashmask, HASH_WAITOK));
|
|
}
|
|
|
|
void
|
|
hashdestroy(void *vhashtbl, struct malloc_type *type, u_long hashmask)
|
|
{
|
|
LIST_HEAD(generic, generic) *hashtbl, *hp;
|
|
|
|
hashtbl = vhashtbl;
|
|
for (hp = hashtbl; hp <= &hashtbl[hashmask]; hp++)
|
|
if (!LIST_EMPTY(hp))
|
|
panic("hashdestroy: hash not empty");
|
|
free(hashtbl, type);
|
|
}
|
|
|
|
static const int primes[] = { 1, 13, 31, 61, 127, 251, 509, 761, 1021, 1531,
|
|
2039, 2557, 3067, 3583, 4093, 4603, 5119, 5623, 6143,
|
|
6653, 7159, 7673, 8191, 12281, 16381, 24571, 32749 };
|
|
#define NPRIMES (sizeof(primes) / sizeof(primes[0]))
|
|
|
|
/*
|
|
* General routine to allocate a prime number sized hash table.
|
|
*/
|
|
void *
|
|
phashinit(int elements, struct malloc_type *type, u_long *nentries)
|
|
{
|
|
long hashsize;
|
|
LIST_HEAD(generic, generic) *hashtbl;
|
|
int i;
|
|
|
|
if (elements <= 0)
|
|
panic("phashinit: bad elements");
|
|
for (i = 1, hashsize = primes[1]; hashsize <= elements;) {
|
|
i++;
|
|
if (i == NPRIMES)
|
|
break;
|
|
hashsize = primes[i];
|
|
}
|
|
hashsize = primes[i - 1];
|
|
hashtbl = malloc((u_long)hashsize * sizeof(*hashtbl), type, M_WAITOK);
|
|
for (i = 0; i < hashsize; i++)
|
|
LIST_INIT(&hashtbl[i]);
|
|
*nentries = hashsize;
|
|
return (hashtbl);
|
|
}
|