/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (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 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#include "gprof.h"

/*
 * look up an address in a sorted-by-address namelist
 * this deals with misses by mapping them to the next lower
 * entry point.
 */
static   int    searchmsg = 0; /* Emit the diagnostic only once */

nltype *
nllookup(mod_info_t *module, pctype address, pctype *nxtsym)
{
        size_t  low = 0, middle, high = module->nname - 1;
        pctype  keyval;
        nltype  *mnl = module->nl;

        /*
         * If this is the program executable in which we are looking up
         * a symbol, then the actual load address will be the same as the
         * address specified in the ELF file. For shared objects, the
         * load address may differ from what is specified in the file. In
         * this case, we may need to look for a different value altogether.
         */
        keyval = module->txt_origin + (address - module->load_base);

        if (keyval < mnl[low].value) {
                if (nxtsym) {
                        *nxtsym = module->load_base +
                                        (mnl[low].value - module->txt_origin);
                }
                return (NULL);
        }

        if (keyval >= mnl[high].value) {
                if (nxtsym)
                        *nxtsym = module->load_end;
                return (&mnl[high]);
        }

        while (low != high) {
                middle = (high + low) >> 1;

                if (mnl[middle].value <= keyval &&
                                            mnl[middle + 1].value > keyval) {
                        if (nxtsym) {
                                *nxtsym = module->load_base +
                                                    (mnl[middle + 1].value -
                                                    module->txt_origin);
                        }
                        return (&mnl[middle]);
                }

                if (mnl[middle].value > keyval) {
                        high = middle;
                } else {
                        low = middle + 1;
                }
        }

        if (searchmsg++ == 0)
                (void) fprintf(stderr, "[nllookup] binary search fails???\n");

        /* must never reach here! */
        return (0);
}

arctype *
arclookup(nltype *parentp, nltype *childp)
{
        arctype *arcp;

        if (parentp == 0 || childp == 0) {
                (void) fprintf(stderr,
                    "[arclookup] parentp == 0 || childp == 0\n");
                return (0);
        }
#ifdef DEBUG
        if (debug & LOOKUPDEBUG) {
                (void) printf("[arclookup] parent %s child %s\n",
                    parentp->name, childp->name);
        }
#endif /* DEBUG */

        for (arcp = parentp->children; arcp; arcp = arcp->arc_childlist) {
#ifdef DEBUG
                if (debug & LOOKUPDEBUG) {
                        (void) printf(
                            "[arclookup]\t arc_parent %s arc_child %s\n",
                            arcp->arc_parentp->name,
                            arcp->arc_childp->name);
                }
#endif /* DEBUG */
                if (arcp->arc_childp == childp) {
                        return (arcp);
                }
        }
        return (0);
}