libelf/common/rawdata.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.
 */

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

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

#include <stdlib.h>
#include "libelf.h"
#include "decl.h"
#include "msg.h"


Elf_Data *
elf_rawdata(Elf_Scn * scn, Elf_Data * data)
{
    Dnode *     d = (Dnode *)data;
    Dnode *     raw;
    Elf_Data *  rc;
    Elf *       elf;

    if (scn == 0)
        return (0);
    elf = scn->s_elf;
    READLOCKS(elf, scn)
    if ((scn->s_myflags & SF_READY) == 0) {
        UPGRADELOCKS(elf, scn)
        if ((scn->s_myflags & SF_READY) == 0)
            (void) _elf_cookscn(scn);
        DOWNGRADELOCKS(elf, scn)
    }

    if (d == 0)
        d = scn->s_hdnode;
    else
        d = d->db_next;

    if (d == 0) {
        READUNLOCKS(elf, scn)
        return (0);
    }

    if (d->db_scn != scn) {
        _elf_seterr(EREQ_DATA, 0);
        READUNLOCKS(elf, scn)
        return (0);
    }

    /*
     * The data may come from a previously constructed Dbuf,
     * from the file's raw memory image, or the file system.
     * "Empty" regions get an empty buffer.
     */

    if (d->db_raw != 0) {
        rc = &d->db_raw->db_data;
        READUNLOCKS(elf, scn)
        return (rc);
    }

    if ((raw = _elf_dnode()) == 0)  {
        READUNLOCKS(elf, scn)
        return (0);
    }
    raw->db_myflags |= DBF_READY;
    if ((d->db_off == 0) || (d->db_fsz == 0)) {
        d->db_raw = raw;
        raw->db_data.d_size = d->db_shsz;
        rc = &raw->db_data;
        READUNLOCKS(elf, scn)
        return (rc);
    }

    /*
     * validate the region
     */

    if ((d->db_off < 0) ||
        (d->db_off >= elf->ed_fsz) ||
        (elf->ed_fsz - d->db_off < d->db_fsz)) {
        _elf_seterr(EFMT_DATA, 0);
        free(raw);
        READUNLOCKS(elf, scn)
        return (0);
    }
    raw->db_data.d_size = d->db_fsz;
    if (elf->ed_raw != 0) {
        raw->db_data.d_buf = (Elf_Void *)(elf->ed_raw + d->db_off);
        d->db_raw = raw;
        rc = &raw->db_data;
        READUNLOCKS(elf, scn)
        return (rc);
    }
    raw->db_buf = (Elf_Void *)_elf_read(elf->ed_fd,
        elf->ed_baseoff + d->db_off, d->db_fsz);
    if (raw->db_buf == 0) {
        free(raw);
        READUNLOCKS(elf, scn)
        return (0);
    }
    raw->db_data.d_buf = raw->db_buf;
    d->db_raw = raw;
    rc = &raw->db_data;
    READUNLOCKS(elf, scn)
    return (rc);
}