common/mdesc/mdesc_getproparcs.c

/*
 * 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 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#pragma ident   "%Z%%M% %I% %E% SMI"

#include <sys/types.h>
#include <sys/mdesc.h>
#include <sys/mdesc_impl.h>

static int md_find_node_arcs(md_impl_t *, mde_cookie_t, mde_str_cookie_t, int,
    mde_cookie_t *, size_t);


/*
 * Return an array containing the node indexes for the arcs in
 * the given node.  The array is allocated using the allocator
 * defined at machine description initialization time and the
 * number of arcs found returned.
 *
 * Input        Description
 * -------------------  ----------------------------------------
 * md_t *       Pointer to md session
 * mde_cookie_t     Node containing arcs
 * char *       Arc name to count (e.g. "fwd" or "back")
 * mde_cookie_t *   Buffer to store indexes, or NULL
 * size_t       Size of buffer
 *
 * Output       Description
 * -------------------  ----------------------------------------
 * int          Count of arcs in node
 */
int
md_get_prop_arcs(md_t *ptr, mde_cookie_t node, char *namep, mde_cookie_t *arcp,
    size_t arcsize)
{
    int      result;
    mde_str_cookie_t prop_name;
    md_impl_t   *mdp;

    mdp = (md_impl_t *)ptr;

    if (node == MDE_INVAL_ELEM_COOKIE) {
        return (-1);
    }

    prop_name = md_find_name(ptr, namep);
    if (prop_name == MDE_INVAL_STR_COOKIE) {
        return (-1);
    }

    result = md_find_node_arcs(mdp, node, prop_name, MDET_PROP_ARC, arcp,
        arcsize);

    return (result);
}


/*
 * Find the number of arcs in the node of the requested prop_name.  If storage
 * is given in arcp, store the first arcsize number of node indexes.
 */
static int
md_find_node_arcs(md_impl_t *mdp, mde_cookie_t node,
    mde_str_cookie_t prop_name, int tag_type, mde_cookie_t *arcp,
    size_t arcsize)
{
    int     result;
    md_element_t    *mdep;
    int     idx;

    /* Get the private node information from session data */
    idx = (int)node;
    mdep = &(mdp->mdep[idx]);

    /* Make sure the cookie is in fact a node */
    if (MDE_TAG(mdep) != MDET_NODE) {
        return (-1);
    }

    /*
     * Walk the elements in the node and find all the arcs of the
     * requested type, and store them in an array.
     */
    result = 0;
    for (idx++, mdep++; MDE_TAG(mdep) != MDET_NODE_END; idx++, mdep++) {
        if ((MDE_TAG(mdep) == tag_type) &&
            (MDE_NAME(mdep) == prop_name)) {
            if (arcp != NULL && result < arcsize) {
                arcp[result] =
                    (mde_cookie_t)MDE_PROP_INDEX(mdep);
            }

            /* Increment the count of arcs found */
            result++;
        }
    }

    /* Return the total count of arcs in the node */
    return (result);
}