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lint: use unsigned integers for storing hash values

The computation of the hash values is unchanged, only the resulting
value (which is always less than 1009 anyway, see HSHSIZ2) is stored as
unsigned as well.

No functional change.

/*	$NetBSD: hash.c,v 1.16 2021/08/22 13:12:39 rillig 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.
 */

#if HAVE_NBTOOL_CONFIG_H
#include "nbtool_config.h"
#endif

#include <sys/cdefs.h>
#if defined(__RCSID) && !defined(lint)
__RCSID("$NetBSD: hash.c,v 1.16 2021/08/22 13:12:39 rillig Exp $");
#endif

/*
 * XXX Really need a generalized hash table package
 */

#include <limits.h>
#include <stddef.h>
#include <stdlib.h>
#include <string.h>

#include "lint2.h"

/* pointer to hash table, initialized in inithash() */
static	hte_t	**htab;

static	u_int	hash(const char *);

/*
 * Initialize hash table.
 */
void
_inithash(hte_t ***tablep)
{

	if (tablep == NULL)
		tablep = &htab;

	*tablep = xcalloc(HSHSIZ2, sizeof(**tablep));
}

/*
 * Compute hash value from a string.
 */
static u_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(hte_t **table, const char *s, bool mknew)
{
	u_int	h;
	hte_t	*hte;

	if (table == NULL)
		table = htab;

	h = hash(s);
	for (hte = table[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 = xmalloc(sizeof(*hte));
	hte->h_name = xstrdup(s);
	hte->h_used = false;
	hte->h_def = false;
	hte->h_static = false;
	hte->h_syms = NULL;
	hte->h_lsym = &hte->h_syms;
	hte->h_calls = NULL;
	hte->h_lcall = &hte->h_calls;
	hte->h_usyms = NULL;
	hte->h_lusym = &hte->h_usyms;
	hte->h_link = table[h];
	hte->h_hte = NULL;
	table[h] = hte;

	return hte;
}

/*
 * Call function f for each name in the hash table.
 */
void
_forall(hte_t **table, void (*f)(hte_t *))
{
	int	i;
	hte_t	*hte;

	if (table == NULL)
		table = htab;

	for (i = 0; i < HSHSIZ2; i++) {
		for (hte = table[i]; hte != NULL; hte = hte->h_link)
			(*f)(hte);
	}
}

/*
 * Free all contents of the hash table that this module allocated.
 */
void
_destroyhash(hte_t **table)
{
	int	i;
	hte_t	*hte, *nexthte;

	if (table == NULL)
		err(1, "_destroyhash called on main hash table");

	for (i = 0; i < HSHSIZ2; i++) {
		for (hte = table[i]; hte != NULL; hte = nexthte) {
			free(__UNCONST(hte->h_name));
			nexthte = hte->h_link;
			free(hte);
		}
	}
	free(table);
}