/*
 * 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.
 */

/*      Copyright (c) 1988 AT&T */
/*        All Rights Reserved   */

#include "libelf.h"
#include "decl.h"
#include "msg.h"


Elf_Scn *
elf_getscn(Elf * elf, size_t index)
{
        Elf_Scn *       s;
        Elf_Scn *       prev_s;
        size_t          j = index;
        size_t          tabsz;

        if (elf == 0)
                return (0);

        ELFRLOCK(elf)
        tabsz = elf->ed_scntabsz;
        if (elf->ed_hdscn == 0) {
                ELFUNLOCK(elf)
                ELFWLOCK(elf)
                if ((elf->ed_hdscn == 0) && (_elf_cook(elf) != OK_YES)) {
                        ELFUNLOCK(elf);
                        return (0);
                }
                ELFUNLOCK(elf);
                ELFRLOCK(elf)
        }
        /*
         * If the section in question is part of a table allocated
         * from within _elf_prescn() then we can index straight
         * to it.
         */
        if (index < tabsz) {
                s = &elf->ed_hdscn[index];
                ELFUNLOCK(elf);
                return (s);
        }

        if (tabsz)
                s = &elf->ed_hdscn[tabsz - 1];
        else
                s = elf->ed_hdscn;

        for (prev_s = 0; s != 0; prev_s = s, s = s->s_next) {
                if (prev_s) {
                        SCNUNLOCK(prev_s)
                }
                SCNLOCK(s)
                if (j == 0) {
                        if (s->s_index == index) {
                                SCNUNLOCK(s)
                                ELFUNLOCK(elf);
                                return (s);
                        }
                        _elf_seterr(EBUG_SCNLIST, 0);
                        SCNUNLOCK(s)
                        ELFUNLOCK(elf)
                        return (0);
                }
                --j;
        }
        if (prev_s) {
                SCNUNLOCK(prev_s)
        }

        _elf_seterr(EREQ_NDX, 0);
        ELFUNLOCK(elf);
        return (0);
}