/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include <sys/types.h>
#include <libdevinfo.h>
#include <fm/topo_mod.h>
#include <pcibus.h>
#include <did.h>

#include "did_impl.h"
#include "did_props.h"

static did_hash_t *did_hash_create(topo_mod_t *);
static void did_hash_destroy(did_hash_t *);

int
did_hash_init(topo_mod_t *hdl)
{
        did_hash_t *dh = did_hash_create(hdl);

        if (dh != NULL) {
                topo_mod_setspecific(hdl, (void *) dh);
                return (0);
        } else {
                return (-1);
        }
}

void
did_hash_fini(topo_mod_t *mod)
{
        did_hash_t *dh = (did_hash_t *)topo_mod_getspecific(mod);

        topo_mod_setspecific(mod, NULL);
        if (dh == NULL)
                return;
        did_hash_destroy(dh);
}

static uint64_t
did_dnhash(di_node_t key)
{
        static uint64_t key_divisor = 0;
        uint64_t keyn;

        /*
         * A bit naughty here, we're aware that a di_info_t is a
         * pointer to a struct.  For our hashing, we want use the size
         * of that struct, which we determine here, somewhat
         * impolitely.
         */
        if (key_divisor == 0)
                key_divisor = sizeof (*key);

        keyn = (uintptr_t)key;

        return (keyn / key_divisor);
}

static did_hash_t *
did_hash_create(topo_mod_t *hdl)
{
        did_hash_t *r = topo_mod_zalloc(hdl, sizeof (did_hash_t));

        if (r == NULL) {
                (void) topo_mod_seterrno(hdl, EMOD_NOMEM);
                return (NULL);
        }
        r->dph_mod = hdl;
        r->dph_hashlen = REC_HASHLEN;
        r->dph_hash = topo_mod_zalloc(hdl,
            r->dph_hashlen * sizeof (did_t *));
        if (r->dph_hash == NULL) {
                topo_mod_free(hdl, r, sizeof (did_hash_t));
                (void) topo_mod_seterrno(hdl, EMOD_NOMEM);
                return (NULL);
        }
        return (r);
}

static void
did_hash_destroy(did_hash_t *ht)
{
        did_t *e, *n;
        int idx;

        if (ht == NULL)
                return;
        for (idx = 0; idx < ht->dph_hashlen; idx++) {
                for (e = ht->dph_hash[idx]; e != NULL; ) {
                        n = e->dp_next;
                        did_destroy(e);
                        e = n;
                }
        }
        topo_mod_free(ht->dph_mod,
            ht->dph_hash, ht->dph_hashlen * sizeof (did_t *));
        topo_mod_free(ht->dph_mod, ht, sizeof (did_hash_t));
}

void
did_hash_insert(topo_mod_t *mp, di_node_t key, did_t *new)
{
        did_hash_t *tab = (did_hash_t *)topo_mod_getspecific(mp);
        did_t *assertchk;
        int idx = did_dnhash(key) % tab->dph_hashlen;

        tab->dph_nelems++;
        did_hold(new);
        topo_mod_dprintf(tab->dph_mod, "Insert [key=%p] into %p, bucket %d\n",
            key, (void *)tab, idx);
        if (tab->dph_hash[idx] == NULL) {
                tab->dph_hash[idx] = new;
                topo_mod_dprintf(tab->dph_mod, "first entry.\n");
        } else {
                /*
                 * We should not be putting in a duplicate entry
                 */
                for (assertchk = tab->dph_hash[idx];
                    assertchk != NULL;
                    assertchk = assertchk->dp_next)
                        assert(assertchk->dp_src != key);
                new->dp_next = tab->dph_hash[idx];
                tab->dph_hash[idx] = new;
        }
}

did_t *
did_hash_lookup(topo_mod_t *mp, di_node_t key)
{
        did_t *e;
        did_hash_t *tab = (did_hash_t *)topo_mod_getspecific(mp);
        int idx = did_dnhash(key) % tab->dph_hashlen;

        e = tab->dph_hash[idx];
        while (e != NULL) {
                if (e->dp_src == key) {
                        did_hold(e);
                        return (e);
                }
                e = e->dp_next;
        }
        return (NULL);
}