source: MondoRescue/branches/2.2.9/mindi-busybox/util-linux/volume_id/iso9660.c@ 3320

/*
 * volume_id - reads filesystem label and uuid
 *
 * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2.1 of the License, or (at your option) any later version.
 *
 *  This library is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

#include "volume_id_internal.h"

#define ISO_SUPERBLOCK_OFFSET       0x8000
#define ISO_SECTOR_SIZE         0x800
#define ISO_VD_OFFSET           (ISO_SUPERBLOCK_OFFSET + ISO_SECTOR_SIZE)
#define ISO_VD_PRIMARY          0x1
#define ISO_VD_SUPPLEMENTARY        0x2
#define ISO_VD_END          0xff
#define ISO_VD_MAX          16

struct iso_volume_descriptor {
    uint8_t     vd_type;
    uint8_t     vd_id[5];
    uint8_t     vd_version;
    uint8_t     flags;
    uint8_t     system_id[32];
    uint8_t     volume_id[32];
    uint8_t     unused[8];
    uint8_t     space_size[8];
    uint8_t     escape_sequences[8];
} PACKED;

struct high_sierra_volume_descriptor {
    uint8_t     foo[8];
    uint8_t     type;
    uint8_t     id[4];
    uint8_t     version;
} PACKED;

int FAST_FUNC volume_id_probe_iso9660(struct volume_id *id /*,uint64_t off*/)
{
#define off ((uint64_t)0)
    uint8_t *buf;
    struct iso_volume_descriptor *is;
    struct high_sierra_volume_descriptor *hs;

    dbg("probing at offset 0x%llx", (unsigned long long) off);

    buf = volume_id_get_buffer(id, off + ISO_SUPERBLOCK_OFFSET, 0x200);
    if (buf == NULL)
        return -1;

    is = (struct iso_volume_descriptor *) buf;

    if (memcmp(is->vd_id, "CD001", 5) == 0) {
        int vd_offset;
        int i;

        dbg("read label from PVD");
//      volume_id_set_label_raw(id, is->volume_id, 32);
        volume_id_set_label_string(id, is->volume_id, 32);

        dbg("looking for SVDs");
        vd_offset = ISO_VD_OFFSET;
        for (i = 0; i < ISO_VD_MAX; i++) {
            uint8_t svd_label[64];

            is = volume_id_get_buffer(id, off + vd_offset, 0x200);
            if (is == NULL || is->vd_type == ISO_VD_END)
                break;
            if (is->vd_type != ISO_VD_SUPPLEMENTARY)
                continue;

            dbg("found SVD at offset 0x%llx", (unsigned long long) (off + vd_offset));
            if (memcmp(is->escape_sequences, "%/@", 3) == 0
             || memcmp(is->escape_sequences, "%/C", 3) == 0
             || memcmp(is->escape_sequences, "%/E", 3) == 0
            ) {
                dbg("Joliet extension found");
                volume_id_set_unicode16((char *)svd_label, sizeof(svd_label), is->volume_id, BE, 32);
                if (memcmp(id->label, svd_label, 16) == 0) {
                    dbg("SVD label is identical, use the possibly longer PVD one");
                    break;
                }

//              volume_id_set_label_raw(id, is->volume_id, 32);
                volume_id_set_label_string(id, svd_label, 32);
//              strcpy(id->type_version, "Joliet Extension");
                goto found;
            }
            vd_offset += ISO_SECTOR_SIZE;
        }
        goto found;
    }

    hs = (struct high_sierra_volume_descriptor *) buf;

    if (memcmp(hs->id, "CDROM", 5) == 0) {
//      strcpy(id->type_version, "High Sierra");
        goto found;
    }

    return -1;

 found:
//  volume_id_set_usage(id, VOLUME_ID_FILESYSTEM);
//  id->type = "iso9660";

    return 0;
}