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/* $OpenBSD: hash.c,v 1.5 2005/11/20 17:09:55 cloder Exp $ */
/* $NetBSD: hash.c,v 1.2 1995/07/03 21:24:47 cgd Exp $ */
/*
* Copyright (c) 1994, 1995 Jochen Pohl
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Jochen Pohl for
* The NetBSD Project.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*/
#ifndef lint
static char rcsid[] = "$OpenBSD: hash.c,v 1.5 2005/11/20 17:09:55 cloder Exp $";
#endif
#include <stddef.h>
#include <string.h>
#include <limits.h>
#include "lint2.h"
/* pointer to hash table, initialized in inithash() */
static hte_t **htab;
static int hash(const char *);
/*
* Initialize hash table.
*/
void
inithash(void)
{
htab = xcalloc(HSHSIZ2, sizeof (hte_t *));
}
/*
* Compute hash value from a string.
*/
static int
hash(const char *s)
{
u_int v;
const u_char *us;
v = 0;
for (us = (const u_char *)s; *us != '\0'; us++) {
v = (v << sizeof (v)) + *us;
v ^= v >> (sizeof (v) * CHAR_BIT - sizeof (v));
}
return (v % HSHSIZ2);
}
/*
* Look for a hash table entry. If no hash table entry for the
* given name exists and mknew is set, create a new one.
*/
hte_t *
hsearch(const char *s, int mknew)
{
int h;
hte_t *hte;
h = hash(s);
for (hte = htab[h]; hte != NULL; hte = hte->h_link) {
if (strcmp(hte->h_name, s) == 0)
break;
}
if (hte != NULL || !mknew)
return (hte);
/* create a new hte */
hte = xalloc(sizeof (hte_t));
memset(hte, 0, sizeof (hte_t));
hte->h_name = xstrdup(s);
hte->h_lsym = &hte->h_syms;
hte->h_lcall = &hte->h_calls;
hte->h_lusym = &hte->h_usyms;
hte->h_link = htab[h];
htab[h] = hte;
return (hte);
}
/*
* Call function f for each name in the hash table.
*/
void
forall(void (*f)(hte_t *))
{
int i;
hte_t *hte;
for (i = 0; i < HSHSIZ2; i++) {
for (hte = htab[i]; hte != NULL; hte = hte->h_link)
(*f)(hte);
}
}
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