MFC r224691, r224700 [1]:

[FreeBSD/stable/8.git] / lib / libarchive / archive_read_support_format_iso9660.c

/*-
 * Copyright (c) 2003-2007 Tim Kientzle
 * Copyright (c) 2009 Andreas Henriksson <andreas@fatal.se>
 * Copyright (c) 2009 Michihiro NAKAJIMA
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "archive_platform.h"
__FBSDID("$FreeBSD$");

#ifdef HAVE_ERRNO_H
#include <errno.h>
#endif
/* #include <stdint.h> */ /* See archive_platform.h */
#include <stdio.h>
#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#include <time.h>
#ifdef HAVE_ZLIB_H
#include <zlib.h>
#endif

#include "archive.h"
#include "archive_endian.h"
#include "archive_entry.h"
#include "archive_private.h"
#include "archive_read_private.h"
#include "archive_string.h"

/*
 * An overview of ISO 9660 format:
 *
 * Each disk is laid out as follows:
 *   * 32k reserved for private use
 *   * Volume descriptor table.  Each volume descriptor
 *     is 2k and specifies basic format information.
 *     The "Primary Volume Descriptor" (PVD) is defined by the
 *     standard and should always be present; other volume
 *     descriptors include various vendor-specific extensions.
 *   * Files and directories.  Each file/dir is specified by
 *     an "extent" (starting sector and length in bytes).
 *     Dirs are just files with directory records packed one
 *     after another.  The PVD contains a single dir entry
 *     specifying the location of the root directory.  Everything
 *     else follows from there.
 *
 * This module works by first reading the volume descriptors, then
 * building a list of directory entries, sorted by starting
 * sector.  At each step, I look for the earliest dir entry that
 * hasn't yet been read, seek forward to that location and read
 * that entry.  If it's a dir, I slurp in the new dir entries and
 * add them to the heap; if it's a regular file, I return the
 * corresponding archive_entry and wait for the client to request
 * the file body.  This strategy allows us to read most compliant
 * CDs with a single pass through the data, as required by libarchive.
 */
#define LOGICAL_BLOCK_SIZE      2048
#define SYSTEM_AREA_BLOCK       16

/* Structure of on-disk primary volume descriptor. */
#define PVD_type_offset 0
#define PVD_type_size 1
#define PVD_id_offset (PVD_type_offset + PVD_type_size)
#define PVD_id_size 5
#define PVD_version_offset (PVD_id_offset + PVD_id_size)
#define PVD_version_size 1
#define PVD_reserved1_offset (PVD_version_offset + PVD_version_size)
#define PVD_reserved1_size 1
#define PVD_system_id_offset (PVD_reserved1_offset + PVD_reserved1_size)
#define PVD_system_id_size 32
#define PVD_volume_id_offset (PVD_system_id_offset + PVD_system_id_size)
#define PVD_volume_id_size 32
#define PVD_reserved2_offset (PVD_volume_id_offset + PVD_volume_id_size)
#define PVD_reserved2_size 8
#define PVD_volume_space_size_offset (PVD_reserved2_offset + PVD_reserved2_size)
#define PVD_volume_space_size_size 8
#define PVD_reserved3_offset (PVD_volume_space_size_offset + PVD_volume_space_size_size)
#define PVD_reserved3_size 32
#define PVD_volume_set_size_offset (PVD_reserved3_offset + PVD_reserved3_size)
#define PVD_volume_set_size_size 4
#define PVD_volume_sequence_number_offset (PVD_volume_set_size_offset + PVD_volume_set_size_size)
#define PVD_volume_sequence_number_size 4
#define PVD_logical_block_size_offset (PVD_volume_sequence_number_offset + PVD_volume_sequence_number_size)
#define PVD_logical_block_size_size 4
#define PVD_path_table_size_offset (PVD_logical_block_size_offset + PVD_logical_block_size_size)
#define PVD_path_table_size_size 8
#define PVD_type_1_path_table_offset (PVD_path_table_size_offset + PVD_path_table_size_size)
#define PVD_type_1_path_table_size 4
#define PVD_opt_type_1_path_table_offset (PVD_type_1_path_table_offset + PVD_type_1_path_table_size)
#define PVD_opt_type_1_path_table_size 4
#define PVD_type_m_path_table_offset (PVD_opt_type_1_path_table_offset + PVD_opt_type_1_path_table_size)
#define PVD_type_m_path_table_size 4
#define PVD_opt_type_m_path_table_offset (PVD_type_m_path_table_offset + PVD_type_m_path_table_size)
#define PVD_opt_type_m_path_table_size 4
#define PVD_root_directory_record_offset (PVD_opt_type_m_path_table_offset + PVD_opt_type_m_path_table_size)
#define PVD_root_directory_record_size 34
#define PVD_volume_set_id_offset (PVD_root_directory_record_offset + PVD_root_directory_record_size)
#define PVD_volume_set_id_size 128
#define PVD_publisher_id_offset (PVD_volume_set_id_offset + PVD_volume_set_id_size)
#define PVD_publisher_id_size 128
#define PVD_preparer_id_offset (PVD_publisher_id_offset + PVD_publisher_id_size)
#define PVD_preparer_id_size 128
#define PVD_application_id_offset (PVD_preparer_id_offset + PVD_preparer_id_size)
#define PVD_application_id_size 128
#define PVD_copyright_file_id_offset (PVD_application_id_offset + PVD_application_id_size)
#define PVD_copyright_file_id_size 37
#define PVD_abstract_file_id_offset (PVD_copyright_file_id_offset + PVD_copyright_file_id_size)
#define PVD_abstract_file_id_size 37
#define PVD_bibliographic_file_id_offset (PVD_abstract_file_id_offset + PVD_abstract_file_id_size)
#define PVD_bibliographic_file_id_size 37
#define PVD_creation_date_offset (PVD_bibliographic_file_id_offset + PVD_bibliographic_file_id_size)
#define PVD_creation_date_size 17
#define PVD_modification_date_offset (PVD_creation_date_offset + PVD_creation_date_size)
#define PVD_modification_date_size 17
#define PVD_expiration_date_offset (PVD_modification_date_offset + PVD_modification_date_size)
#define PVD_expiration_date_size 17
#define PVD_effective_date_offset (PVD_expiration_date_offset + PVD_expiration_date_size)
#define PVD_effective_date_size 17
#define PVD_file_structure_version_offset (PVD_effective_date_offset + PVD_effective_date_size)
#define PVD_file_structure_version_size 1
#define PVD_reserved4_offset (PVD_file_structure_version_offset + PVD_file_structure_version_size)
#define PVD_reserved4_size 1
#define PVD_application_data_offset (PVD_reserved4_offset + PVD_reserved4_size)
#define PVD_application_data_size 512
#define PVD_reserved5_offset (PVD_application_data_offset + PVD_application_data_size)
#define PVD_reserved5_size (2048 - PVD_reserved5_offset)

/* TODO: It would make future maintenance easier to just hardcode the
 * above values.  In particular, ECMA119 states the offsets as part of
 * the standard.  That would eliminate the need for the following check.*/
#if PVD_reserved5_offset != 1395
#error PVD offset and size definitions are wrong.
#endif


/* Structure of optional on-disk supplementary volume descriptor. */
#define SVD_type_offset 0
#define SVD_type_size 1
#define SVD_id_offset (SVD_type_offset + SVD_type_size)
#define SVD_id_size 5
#define SVD_version_offset (SVD_id_offset + SVD_id_size)
#define SVD_version_size 1
/* ... */
#define SVD_reserved1_offset    72
#define SVD_reserved1_size      8
#define SVD_volume_space_size_offset 80
#define SVD_volume_space_size_size 8
#define SVD_escape_sequences_offset (SVD_volume_space_size_offset + SVD_volume_space_size_size)
#define SVD_escape_sequences_size 32
/* ... */
#define SVD_logical_block_size_offset 128
#define SVD_logical_block_size_size 4
#define SVD_type_L_path_table_offset 140
#define SVD_type_M_path_table_offset 148
/* ... */
#define SVD_root_directory_record_offset 156
#define SVD_root_directory_record_size 34
#define SVD_file_structure_version_offset 881
#define SVD_reserved2_offset    882
#define SVD_reserved2_size      1
#define SVD_reserved3_offset    1395
#define SVD_reserved3_size      653
/* ... */
/* FIXME: validate correctness of last SVD entry offset. */

/* Structure of an on-disk directory record. */
/* Note:  ISO9660 stores each multi-byte integer twice, once in
 * each byte order.  The sizes here are the size of just one
 * of the two integers.  (This is why the offset of a field isn't
 * the same as the offset+size of the previous field.) */
#define DR_length_offset 0
#define DR_length_size 1
#define DR_ext_attr_length_offset 1
#define DR_ext_attr_length_size 1
#define DR_extent_offset 2
#define DR_extent_size 4
#define DR_size_offset 10
#define DR_size_size 4
#define DR_date_offset 18
#define DR_date_size 7
#define DR_flags_offset 25
#define DR_flags_size 1
#define DR_file_unit_size_offset 26
#define DR_file_unit_size_size 1
#define DR_interleave_offset 27
#define DR_interleave_size 1
#define DR_volume_sequence_number_offset 28
#define DR_volume_sequence_number_size 2
#define DR_name_len_offset 32
#define DR_name_len_size 1
#define DR_name_offset 33

#ifdef HAVE_ZLIB_H
static const unsigned char zisofs_magic[8] = {
        0x37, 0xE4, 0x53, 0x96, 0xC9, 0xDB, 0xD6, 0x07
};

struct zisofs {
        /* Set 1 if this file compressed by paged zlib */
        int              pz;
        int              pz_log2_bs; /* Log2 of block size */
        uint64_t         pz_uncompressed_size;

        int              initialized;
        unsigned char   *uncompressed_buffer;
        size_t           uncompressed_buffer_size;

        uint32_t         pz_offset;
        unsigned char    header[16];
        size_t           header_avail;
        int              header_passed;
        unsigned char   *block_pointers;
        size_t           block_pointers_alloc;
        size_t           block_pointers_size;
        size_t           block_pointers_avail;
        size_t           block_off;
        uint32_t         block_avail;

        z_stream         stream;
        int              stream_valid;
};
#else
struct zisofs {
        /* Set 1 if this file compressed by paged zlib */
        int              pz;
};
#endif

struct content {
        uint64_t         offset;/* Offset on disk.              */
        uint64_t         size;  /* File size in bytes.          */
        struct content  *next;
};

/* In-memory storage for a directory record. */
struct file_info {
        struct file_info        *use_next;
        struct file_info        *parent;
        struct file_info        *next;
        int              subdirs;
        uint64_t         key;           /* Heap Key.                    */
        uint64_t         offset;        /* Offset on disk.              */
        uint64_t         size;          /* File size in bytes.          */
        uint32_t         ce_offset;     /* Offset of CE.                */
        uint32_t         ce_size;       /* Size of CE.                  */
        char             re;            /* Having RRIP "RE" extension.  */
        uint64_t         cl_offset;     /* Having RRIP "CL" extension.  */
        int              birthtime_is_set;
        time_t           birthtime;     /* File created time.           */
        time_t           mtime;         /* File last modified time.     */
        time_t           atime;         /* File last accessed time.     */
        time_t           ctime;         /* File attribute change time.  */
        uint64_t         rdev;          /* Device number.               */
        mode_t           mode;
        uid_t            uid;
        gid_t            gid;
        int64_t          number;
        int              nlinks;
        struct archive_string name; /* Pathname */
        char             name_continues; /* Non-zero if name continues */
        struct archive_string symlink;
        char             symlink_continues; /* Non-zero if link continues */
        /* Set 1 if this file compressed by paged zlib(zisofs) */
        int              pz;
        int              pz_log2_bs; /* Log2 of block size */
        uint64_t         pz_uncompressed_size;
        /* Set 1 if this file is multi extent. */
        int              multi_extent;
        struct {
                struct content  *first;
                struct content  **last;
        } contents;
        char             exposed;
};

struct heap_queue {
        struct file_info **files;
        int              allocated;
        int              used;
};

struct iso9660 {
        int     magic;
#define ISO9660_MAGIC   0x96609660

        int opt_support_joliet;
        int opt_support_rockridge;

        struct archive_string pathname;
        char    seenRockridge;  /* Set true if RR extensions are used. */
        char    seenSUSP;       /* Set true if SUSP is beging used. */
        char    seenJoliet;

        unsigned char   suspOffset;
        struct file_info *rr_moved;
        struct heap_queue                re_dirs;
        struct heap_queue                cl_files;
        struct read_ce_queue {
                struct read_ce_req {
                        uint64_t         offset;/* Offset of CE on disk. */
                        struct file_info *file;
                }               *reqs;
                int              cnt;
                int              allocated;
        }       read_ce_req;

        int64_t         previous_number;
        struct archive_string previous_pathname;

        struct file_info                *use_files;
        struct heap_queue                pending_files;
        struct {
                struct file_info        *first;
                struct file_info        **last;
        }       cache_files;

        uint64_t current_position;
        ssize_t logical_block_size;
        uint64_t volume_size; /* Total size of volume in bytes. */
        int32_t  volume_block;/* Total size of volume in logical blocks. */

        struct vd {
                int             location;       /* Location of Extent.  */
                uint32_t        size;
        } primary, joliet;

        off_t   entry_sparse_offset;
        int64_t entry_bytes_remaining;
        struct zisofs    entry_zisofs;
        struct content  *entry_content;
};

static int      archive_read_format_iso9660_bid(struct archive_read *);
static int      archive_read_format_iso9660_options(struct archive_read *,
                    const char *, const char *);
static int      archive_read_format_iso9660_cleanup(struct archive_read *);
static int      archive_read_format_iso9660_read_data(struct archive_read *,
                    const void **, size_t *, off_t *);
static int      archive_read_format_iso9660_read_data_skip(struct archive_read *);
static int      archive_read_format_iso9660_read_header(struct archive_read *,
                    struct archive_entry *);
static const char *build_pathname(struct archive_string *, struct file_info *);
#if DEBUG
static void     dump_isodirrec(FILE *, const unsigned char *isodirrec);
#endif
static time_t   time_from_tm(struct tm *);
static time_t   isodate17(const unsigned char *);
static time_t   isodate7(const unsigned char *);
static int      isBootRecord(struct iso9660 *, const unsigned char *);
static int      isVolumePartition(struct iso9660 *, const unsigned char *);
static int      isVDSetTerminator(struct iso9660 *, const unsigned char *);
static int      isJolietSVD(struct iso9660 *, const unsigned char *);
static int      isSVD(struct iso9660 *, const unsigned char *);
static int      isEVD(struct iso9660 *, const unsigned char *);
static int      isPVD(struct iso9660 *, const unsigned char *);
static struct file_info *next_cache_entry(struct iso9660 *iso9660);
static int      next_entry_seek(struct archive_read *a, struct iso9660 *iso9660,
                    struct file_info **pfile);
static struct file_info *
                parse_file_info(struct archive_read *a,
                    struct file_info *parent, const unsigned char *isodirrec);
static int      parse_rockridge(struct archive_read *a,
                    struct file_info *file, const unsigned char *start,
                    const unsigned char *end);
static int      register_CE(struct archive_read *a, int32_t location,
                    struct file_info *file);
static int      read_CE(struct archive_read *a, struct iso9660 *iso9660);
static void     parse_rockridge_NM1(struct file_info *,
                    const unsigned char *, int);
static void     parse_rockridge_SL1(struct file_info *,
                    const unsigned char *, int);
static void     parse_rockridge_TF1(struct file_info *,
                    const unsigned char *, int);
static void     parse_rockridge_ZF1(struct file_info *,
                    const unsigned char *, int);
static void     register_file(struct iso9660 *, struct file_info *);
static void     release_files(struct iso9660 *);
static unsigned toi(const void *p, int n);
static inline void cache_add_entry(struct iso9660 *iso9660,
                    struct file_info *file);
static inline void cache_add_to_next_of_parent(struct iso9660 *iso9660,
                    struct file_info *file);
static inline struct file_info *cache_get_entry(struct iso9660 *iso9660);
static void     heap_add_entry(struct heap_queue *heap,
                    struct file_info *file, uint64_t key);
static struct file_info *heap_get_entry(struct heap_queue *heap);

#define add_entry(iso9660, file)        \
        heap_add_entry(&((iso9660)->pending_files), file, file->offset)
#define next_entry(iso9660)             \
        heap_get_entry(&((iso9660)->pending_files))

int
archive_read_support_format_iso9660(struct archive *_a)
{
        struct archive_read *a = (struct archive_read *)_a;
        struct iso9660 *iso9660;
        int r;

        iso9660 = (struct iso9660 *)malloc(sizeof(*iso9660));
        if (iso9660 == NULL) {
                archive_set_error(&a->archive, ENOMEM, "Can't allocate iso9660 data");
                return (ARCHIVE_FATAL);
        }
        memset(iso9660, 0, sizeof(*iso9660));
        iso9660->magic = ISO9660_MAGIC;
        iso9660->cache_files.first = NULL;
        iso9660->cache_files.last = &(iso9660->cache_files.first);
        /* Enable to support Joliet extensions by default.      */
        iso9660->opt_support_joliet = 1;
        /* Enable to support Rock Ridge extensions by default.  */
        iso9660->opt_support_rockridge = 1;

        r = __archive_read_register_format(a,
            iso9660,
            "iso9660",
            archive_read_format_iso9660_bid,
            archive_read_format_iso9660_options,
            archive_read_format_iso9660_read_header,
            archive_read_format_iso9660_read_data,
            archive_read_format_iso9660_read_data_skip,
            archive_read_format_iso9660_cleanup);

        if (r != ARCHIVE_OK) {
                free(iso9660);
                return (r);
        }
        return (ARCHIVE_OK);
}


static int
archive_read_format_iso9660_bid(struct archive_read *a)
{
        struct iso9660 *iso9660;
        ssize_t bytes_read;
        const void *h;
        const unsigned char *p;
        int seenTerminator;

        iso9660 = (struct iso9660 *)(a->format->data);

        /*
         * Skip the first 32k (reserved area) and get the first
         * 8 sectors of the volume descriptor table.  Of course,
         * if the I/O layer gives us more, we'll take it.
         */
#define RESERVED_AREA   (SYSTEM_AREA_BLOCK * LOGICAL_BLOCK_SIZE)
        h = __archive_read_ahead(a,
            RESERVED_AREA + 8 * LOGICAL_BLOCK_SIZE,
            &bytes_read);
        if (h == NULL)
            return (-1);
        p = (const unsigned char *)h;

        /* Skip the reserved area. */
        bytes_read -= RESERVED_AREA;
        p += RESERVED_AREA;

        /* Check each volume descriptor. */
        seenTerminator = 0;
        for (; bytes_read > LOGICAL_BLOCK_SIZE;
            bytes_read -= LOGICAL_BLOCK_SIZE, p += LOGICAL_BLOCK_SIZE) {
                /* Do not handle undefined Volume Descriptor Type. */
                if (p[0] >= 4 && p[0] <= 254)
                        return (0);
                /* Standard Identifier must be "CD001" */
                if (memcmp(p + 1, "CD001", 5) != 0)
                        return (0);
                if (!iso9660->primary.location) {
                        if (isPVD(iso9660, p))
                                continue;
                }
                if (!iso9660->joliet.location) {
                        if (isJolietSVD(iso9660, p))
                                continue;
                }
                if (isBootRecord(iso9660, p))
                        continue;
                if (isEVD(iso9660, p))
                        continue;
                if (isSVD(iso9660, p))
                        continue;
                if (isVolumePartition(iso9660, p))
                        continue;
                if (isVDSetTerminator(iso9660, p)) {
                        seenTerminator = 1;
                        break;
                }
                return (0);
        }
        /*
         * ISO 9660 format must have Primary Volume Descriptor and
         * Volume Descriptor Set Terminator.
         */
        if (seenTerminator && iso9660->primary.location > 16)
                return (48);

        /* We didn't find a valid PVD; return a bid of zero. */
        return (0);
}

static int
archive_read_format_iso9660_options(struct archive_read *a,
                const char *key, const char *val)
{
        struct iso9660 *iso9660;

        iso9660 = (struct iso9660 *)(a->format->data);

        if (strcmp(key, "joliet") == 0) {
                if (val == NULL || strcmp(val, "off") == 0 ||
                                strcmp(val, "ignore") == 0 ||
                                strcmp(val, "disable") == 0 ||
                                strcmp(val, "0") == 0)
                        iso9660->opt_support_joliet = 0;
                else
                        iso9660->opt_support_joliet = 1;
                return (ARCHIVE_OK);
        }
        if (strcmp(key, "rockridge") == 0 ||
            strcmp(key, "Rockridge") == 0) {
                iso9660->opt_support_rockridge = val != NULL;
                return (ARCHIVE_OK);
        }

        /* Note: The "warn" return is just to inform the options
         * supervisor that we didn't handle it.  It will generate
         * a suitable error if noone used this option. */
        return (ARCHIVE_WARN);
}

static int
isBootRecord(struct iso9660 *iso9660, const unsigned char *h)
{
        (void)iso9660; /* UNUSED */

        /* Type of the Volume Descriptor Boot Record must be 0. */
        if (h[0] != 0)
                return (0);

        /* Volume Descriptor Version must be 1. */
        if (h[6] != 1)
                return (0);

        return (1);
}

static int
isVolumePartition(struct iso9660 *iso9660, const unsigned char *h)
{
        int32_t location;

        /* Type of the Volume Partition Descriptor must be 3. */
        if (h[0] != 3)
                return (0);

        /* Volume Descriptor Version must be 1. */
        if (h[6] != 1)
                return (0);
        /* Unused Field */
        if (h[7] != 0)
                return (0);

        location = archive_le32dec(h + 72);
        if (location <= SYSTEM_AREA_BLOCK ||
            location >= iso9660->volume_block)
                return (0);
        if ((uint32_t)location != archive_be32dec(h + 76))
                return (0);

        return (1);
}

static int
isVDSetTerminator(struct iso9660 *iso9660, const unsigned char *h)
{
        int i;

        (void)iso9660; /* UNUSED */

        /* Type of the Volume Descriptor Set Terminator must be 255. */
        if (h[0] != 255)
                return (0);

        /* Volume Descriptor Version must be 1. */
        if (h[6] != 1)
                return (0);

        /* Reserved field must be 0. */
        for (i = 7; i < 2048; ++i)
                if (h[i] != 0)
                        return (0);

        return (1);
}

static int
isJolietSVD(struct iso9660 *iso9660, const unsigned char *h)
{
        const unsigned char *p;
        ssize_t logical_block_size;
        int32_t volume_block;

        /* Check if current sector is a kind of Supplementary Volume
         * Descriptor. */
        if (!isSVD(iso9660, h))
                return (0);

        /* FIXME: do more validations according to joliet spec. */

        /* check if this SVD contains joliet extension! */
        p = h + SVD_escape_sequences_offset;
        /* N.B. Joliet spec says p[1] == '\\', but.... */
        if (p[0] == '%' && p[1] == '/') {
                int level = 0;

                if (p[2] == '@')
                        level = 1;
                else if (p[2] == 'C')
                        level = 2;
                else if (p[2] == 'E')
                        level = 3;
                else /* not joliet */
                        return (0);

                iso9660->seenJoliet = level;

        } else /* not joliet */
                return (0);

        logical_block_size =
            archive_le16dec(h + SVD_logical_block_size_offset);
        volume_block = archive_le32dec(h + SVD_volume_space_size_offset);

        iso9660->logical_block_size = logical_block_size;
        iso9660->volume_block = volume_block;
        iso9660->volume_size = logical_block_size * (uint64_t)volume_block;
        /* Read Root Directory Record in Volume Descriptor. */
        p = h + SVD_root_directory_record_offset;
        iso9660->joliet.location = archive_le32dec(p + DR_extent_offset);
        iso9660->joliet.size = archive_le32dec(p + DR_size_offset);

        return (48);
}

static int
isSVD(struct iso9660 *iso9660, const unsigned char *h)
{
        const unsigned char *p;
        ssize_t logical_block_size;
        int32_t volume_block;
        int32_t location;
        int i;

        (void)iso9660; /* UNUSED */

        /* Type 2 means it's a SVD. */
        if (h[SVD_type_offset] != 2)
                return (0);

        /* Reserved field must be 0. */
        for (i = 0; i < SVD_reserved1_size; ++i)
                if (h[SVD_reserved1_offset + i] != 0)
                        return (0);
        for (i = 0; i < SVD_reserved2_size; ++i)
                if (h[SVD_reserved2_offset + i] != 0)
                        return (0);
        for (i = 0; i < SVD_reserved3_size; ++i)
                if (h[SVD_reserved3_offset + i] != 0)
                        return (0);

        /* File structure version must be 1 for ISO9660/ECMA119. */
        if (h[SVD_file_structure_version_offset] != 1)
                return (0);

        logical_block_size =
            archive_le16dec(h + SVD_logical_block_size_offset);
        if (logical_block_size <= 0)
                return (0);

        volume_block = archive_le32dec(h + SVD_volume_space_size_offset);
        if (volume_block <= SYSTEM_AREA_BLOCK+4)
                return (0);

        /* Location of Occurrence of Type L Path Table must be
         * available location,
         * >= SYSTEM_AREA_BLOCK(16) + 2 and < Volume Space Size. */
        location = archive_le32dec(h+SVD_type_L_path_table_offset);
        if (location < SYSTEM_AREA_BLOCK+2 || location >= volume_block)
                return (0);

        /* The Type M Path Table must be at a valid location (WinISO
         * and probably other programs omit this, so we allow zero)
         *
         * >= SYSTEM_AREA_BLOCK(16) + 2 and < Volume Space Size. */
        location = archive_be32dec(h+SVD_type_M_path_table_offset);
        if ((location > 0 && location < SYSTEM_AREA_BLOCK+2)
            || location >= volume_block)
                return (0);

        /* Read Root Directory Record in Volume Descriptor. */
        p = h + SVD_root_directory_record_offset;
        if (p[DR_length_offset] != 34)
                return (0);

        return (48);
}

static int
isEVD(struct iso9660 *iso9660, const unsigned char *h)
{
        const unsigned char *p;
        ssize_t logical_block_size;
        int32_t volume_block;
        int32_t location;
        int i;

        (void)iso9660; /* UNUSED */

        /* Type of the Enhanced Volume Descriptor must be 2. */
        if (h[PVD_type_offset] != 2)
                return (0);

        /* EVD version must be 2. */
        if (h[PVD_version_offset] != 2)
                return (0);

        /* Reserved field must be 0. */
        if (h[PVD_reserved1_offset] != 0)
                return (0);

        /* Reserved field must be 0. */
        for (i = 0; i < PVD_reserved2_size; ++i)
                if (h[PVD_reserved2_offset + i] != 0)
                        return (0);

        /* Reserved field must be 0. */
        for (i = 0; i < PVD_reserved3_size; ++i)
                if (h[PVD_reserved3_offset + i] != 0)
                        return (0);

        /* Logical block size must be > 0. */
        /* I've looked at Ecma 119 and can't find any stronger
         * restriction on this field. */
        logical_block_size =
            archive_le16dec(h + PVD_logical_block_size_offset);
        if (logical_block_size <= 0)
                return (0);

        volume_block =
            archive_le32dec(h + PVD_volume_space_size_offset);
        if (volume_block <= SYSTEM_AREA_BLOCK+4)
                return (0);

        /* File structure version must be 2 for ISO9660:1999. */
        if (h[PVD_file_structure_version_offset] != 2)
                return (0);

        /* Location of Occurrence of Type L Path Table must be
         * available location,
         * >= SYSTEM_AREA_BLOCK(16) + 2 and < Volume Space Size. */
        location = archive_le32dec(h+PVD_type_1_path_table_offset);
        if (location < SYSTEM_AREA_BLOCK+2 || location >= volume_block)
                return (0);

        /* Location of Occurrence of Type M Path Table must be
         * available location,
         * >= SYSTEM_AREA_BLOCK(16) + 2 and < Volume Space Size. */
        location = archive_be32dec(h+PVD_type_m_path_table_offset);
        if ((location > 0 && location < SYSTEM_AREA_BLOCK+2)
            || location >= volume_block)
                return (0);

        /* Reserved field must be 0. */
        for (i = 0; i < PVD_reserved4_size; ++i)
                if (h[PVD_reserved4_offset + i] != 0)
                        return (0);

        /* Reserved field must be 0. */
        for (i = 0; i < PVD_reserved5_size; ++i)
                if (h[PVD_reserved5_offset + i] != 0)
                        return (0);

        /* Read Root Directory Record in Volume Descriptor. */
        p = h + PVD_root_directory_record_offset;
        if (p[DR_length_offset] != 34)
                return (0);

        return (48);
}

static int
isPVD(struct iso9660 *iso9660, const unsigned char *h)
{
        const unsigned char *p;
        ssize_t logical_block_size;
        int32_t volume_block;
        int32_t location;
        int i;

        /* Type of the Primary Volume Descriptor must be 1. */
        if (h[PVD_type_offset] != 1)
                return (0);

        /* PVD version must be 1. */
        if (h[PVD_version_offset] != 1)
                return (0);

        /* Reserved field must be 0. */
        if (h[PVD_reserved1_offset] != 0)
                return (0);

        /* Reserved field must be 0. */
        for (i = 0; i < PVD_reserved2_size; ++i)
                if (h[PVD_reserved2_offset + i] != 0)
                        return (0);

        /* Reserved field must be 0. */
        for (i = 0; i < PVD_reserved3_size; ++i)
                if (h[PVD_reserved3_offset + i] != 0)
                        return (0);

        /* Logical block size must be > 0. */
        /* I've looked at Ecma 119 and can't find any stronger
         * restriction on this field. */
        logical_block_size =
            archive_le16dec(h + PVD_logical_block_size_offset);
        if (logical_block_size <= 0)
                return (0);

        volume_block = archive_le32dec(h + PVD_volume_space_size_offset);
        if (volume_block <= SYSTEM_AREA_BLOCK+4)
                return (0);

        /* File structure version must be 1 for ISO9660/ECMA119. */
        if (h[PVD_file_structure_version_offset] != 1)
                return (0);

        /* Location of Occurrence of Type L Path Table must be
         * available location,
         * > SYSTEM_AREA_BLOCK(16) + 2 and < Volume Space Size. */
        location = archive_le32dec(h+PVD_type_1_path_table_offset);
        if (location < SYSTEM_AREA_BLOCK+2 || location >= volume_block)
                return (0);

        /* The Type M Path Table must also be at a valid location
         * (although ECMA 119 requires a Type M Path Table, WinISO and
         * probably other programs omit it, so we permit a zero here)
         *
         * >= SYSTEM_AREA_BLOCK(16) + 2 and < Volume Space Size. */
        location = archive_be32dec(h+PVD_type_m_path_table_offset);
        if ((location > 0 && location < SYSTEM_AREA_BLOCK+2)
            || location >= volume_block)
                return (0);

        /* Reserved field must be 0. */
        /* FreeBSD: makefs erroneously created images with 0x20 */
        for (i = 0; i < PVD_reserved4_size; ++i)
                if (h[PVD_reserved4_offset + i] != 0 &&
                    h[PVD_reserved4_offset + i] != 32)
                        return (0);

        /* Reserved field must be 0. */
        for (i = 0; i < PVD_reserved5_size; ++i)
                if (h[PVD_reserved5_offset + i] != 0)
                        return (0);

        /* XXX TODO: Check other values for sanity; reject more
         * malformed PVDs. XXX */

        /* Read Root Directory Record in Volume Descriptor. */
        p = h + PVD_root_directory_record_offset;
        if (p[DR_length_offset] != 34)
                return (0);

        iso9660->logical_block_size = logical_block_size;
        iso9660->volume_block = volume_block;
        iso9660->volume_size = logical_block_size * (uint64_t)volume_block;
        iso9660->primary.location = archive_le32dec(p + DR_extent_offset);
        iso9660->primary.size = archive_le32dec(p + DR_size_offset);

        return (48);
}

static int
read_children(struct archive_read *a, struct file_info *parent)
{
        struct iso9660 *iso9660;
        const unsigned char *b, *p;
        struct file_info *multi;
        size_t step;

        iso9660 = (struct iso9660 *)(a->format->data);
        if (iso9660->current_position > parent->offset) {
                archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
                    "Ignoring out-of-order directory (%s) %jd > %jd",
                    parent->name.s,
                    iso9660->current_position,
                    parent->offset);
                return (ARCHIVE_WARN);
        }
        if (parent->offset + parent->size > iso9660->volume_size) {
                archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
                    "Directory is beyond end-of-media: %s",
                    parent->name);
                return (ARCHIVE_WARN);
        }
        if (iso9660->current_position < parent->offset) {
                int64_t skipsize;

                skipsize = parent->offset - iso9660->current_position;
                skipsize = __archive_read_skip(a, skipsize);
                if (skipsize < 0)
                        return ((int)skipsize);
                iso9660->current_position = parent->offset;
        }

        step = ((parent->size + iso9660->logical_block_size -1) /
            iso9660->logical_block_size) * iso9660->logical_block_size;
        b = __archive_read_ahead(a, step, NULL);
        if (b == NULL) {
                archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
                    "Failed to read full block when scanning "
                    "ISO9660 directory list");
                return (ARCHIVE_FATAL);
        }
        __archive_read_consume(a, step);
        iso9660->current_position += step;
        multi = NULL;
        while (step) {
                p = b;
                b += iso9660->logical_block_size;
                step -= iso9660->logical_block_size;
                for (; *p != 0 && p < b && p + *p <= b; p += *p) {
                        struct file_info *child;

                        /* N.B.: these special directory identifiers
                         * are 8 bit "values" even on a
                         * Joliet CD with UCS-2 (16bit) encoding.
                         */

                        /* Skip '.' entry. */
                        if (*(p + DR_name_len_offset) == 1
                            && *(p + DR_name_offset) == '\0')
                                continue;
                        /* Skip '..' entry. */
                        if (*(p + DR_name_len_offset) == 1
                            && *(p + DR_name_offset) == '\001')
                                continue;
                        child = parse_file_info(a, parent, p);
                        if (child == NULL)
                                return (ARCHIVE_FATAL);
                        if (child->cl_offset)
                                heap_add_entry(&(iso9660->cl_files),
                                    child, child->cl_offset);
                        else {
                                if (child->multi_extent || multi != NULL) {
                                        struct content *con;

                                        if (multi == NULL) {
                                                multi = child;
                                                multi->contents.first = NULL;
                                                multi->contents.last =
                                                    &(multi->contents.first);
                                        }
                                        con = malloc(sizeof(struct content));
                                        if (con == NULL) {
                                                archive_set_error(
                                                    &a->archive, ENOMEM,
                                                    "No memory for "
                                                    "multi extent");
                                                return (ARCHIVE_FATAL);
                                        }
                                        con->offset = child->offset;
                                        con->size = child->size;
                                        con->next = NULL;
                                        *multi->contents.last = con;
                                        multi->contents.last = &(con->next);
                                        if (multi == child)
                                                add_entry(iso9660, child);
                                        else {
                                                multi->size += child->size;
                                                if (!child->multi_extent)
                                                        multi = NULL;
                                        }
                                } else
                                        add_entry(iso9660, child);
                        }
                }
        }

        /* Read data which recorded by RRIP "CE" extension. */
        if (read_CE(a, iso9660) != ARCHIVE_OK)
                return (ARCHIVE_FATAL);

        return (ARCHIVE_OK);
}

static int
relocate_dir(struct iso9660 *iso9660, struct file_info *file)
{
        struct file_info *re;

        re = heap_get_entry(&(iso9660->re_dirs));
        while (re != NULL && re->offset < file->cl_offset) {
                /* This case is wrong pattern.
                 * But dont't reject this directory entry to be robust. */
                cache_add_entry(iso9660, re);
                re = heap_get_entry(&(iso9660->re_dirs));
        }
        if (re == NULL)
                /* This case is wrong pattern. */
                return (0);
        if (re->offset == file->cl_offset) {
                re->parent->subdirs--;
                re->parent = file->parent;
                re->parent->subdirs++;
                cache_add_to_next_of_parent(iso9660, re);
                return (1);
        } else
                /* This case is wrong pattern. */
                heap_add_entry(&(iso9660->re_dirs), re, re->offset);
        return (0);
}

static int
read_entries(struct archive_read *a)
{
        struct iso9660 *iso9660;
        struct file_info *file;
        int r;

        iso9660 = (struct iso9660 *)(a->format->data);

        while ((file = next_entry(iso9660)) != NULL &&
            (file->mode & AE_IFMT) == AE_IFDIR) {
                r = read_children(a, file);
                if (r != ARCHIVE_OK)
                        return (r);

                if (iso9660->seenRockridge &&
                    file->parent != NULL &&
                    file->parent->parent == NULL &&
                    iso9660->rr_moved == NULL &&
                    (strcmp(file->name.s, "rr_moved") == 0 ||
                     strcmp(file->name.s, ".rr_moved") == 0)) {
                        iso9660->rr_moved = file;
                } else if (file->re)
                        heap_add_entry(&(iso9660->re_dirs), file,
                            file->offset);
                else
                        cache_add_entry(iso9660, file);
        }
        if (file != NULL)
                add_entry(iso9660, file);

        if (iso9660->rr_moved != NULL) {
                /*
                 * Relocate directory which rr_moved has.
                 */
                while ((file = heap_get_entry(&(iso9660->cl_files))) != NULL)
                        relocate_dir(iso9660, file);

                /* If rr_moved directory still has children,
                 * Add rr_moved into pending_files to show
                 */
                if (iso9660->rr_moved->subdirs) {
                        cache_add_entry(iso9660, iso9660->rr_moved);
                        /* If entries which have "RE" extension are still
                         * remaining(this case is unlikely except ISO image
                         * is broken), the entries won't be exposed. */
                        while ((file = heap_get_entry(&(iso9660->re_dirs))) != NULL)
                                cache_add_entry(iso9660, file);
                } else
                        iso9660->rr_moved->parent->subdirs--;
        } else {
                /*
                 * In case ISO image is broken. If the name of rr_moved
                 * directory has been changed by damage, subdirectories
                 * of rr_moved entry won't be exposed.
                 */
                while ((file = heap_get_entry(&(iso9660->re_dirs))) != NULL)
                        cache_add_entry(iso9660, file);
        }

        return (ARCHIVE_OK);
}

static int
archive_read_format_iso9660_read_header(struct archive_read *a,
    struct archive_entry *entry)
{
        struct iso9660 *iso9660;
        struct file_info *file;
        int r, rd_r;

        iso9660 = (struct iso9660 *)(a->format->data);

        if (!a->archive.archive_format) {
                a->archive.archive_format = ARCHIVE_FORMAT_ISO9660;
                a->archive.archive_format_name = "ISO9660";
        }

        if (iso9660->current_position == 0) {
                int64_t skipsize;
                struct vd *vd;
                const void *block;
                char seenJoliet;

                vd = &(iso9660->primary);
                if (!iso9660->opt_support_joliet)
                        iso9660->seenJoliet = 0;
                if (iso9660->seenJoliet &&
                        vd->location > iso9660->joliet.location)
                        /* This condition is unlikely; by way of caution. */
                        vd = &(iso9660->joliet);

                skipsize = LOGICAL_BLOCK_SIZE * vd->location;
                skipsize = __archive_read_skip(a, skipsize);
                if (skipsize < 0)
                        return ((int)skipsize);
                iso9660->current_position = skipsize;

                block = __archive_read_ahead(a, vd->size, NULL);
                if (block == NULL) {
                        archive_set_error(&a->archive,
                            ARCHIVE_ERRNO_MISC,
                            "Failed to read full block when scanning "
                            "ISO9660 directory list");
                        return (ARCHIVE_FATAL);
                }

                /*
                 * While reading Root Directory, flag seenJoliet
                 * must be zero to avoid converting special name
                 * 0x00(Current Directory) and next byte to UCS2.
                 */
                seenJoliet = iso9660->seenJoliet;/* Save flag. */
                iso9660->seenJoliet = 0;
                file = parse_file_info(a, NULL, block);
                if (file == NULL)
                        return (ARCHIVE_FATAL);
                iso9660->seenJoliet = seenJoliet;
                if (vd == &(iso9660->primary) && iso9660->seenRockridge
                    && iso9660->seenJoliet)
                        /*
                         * If iso image has RockRidge and Joliet,
                         * we use RockRidge Extensions.
                         */
                        iso9660->seenJoliet = 0;
                if (vd == &(iso9660->primary) && !iso9660->seenRockridge
                    && iso9660->seenJoliet) {
                        /* Switch reading data from primary to joliet. */ 
                        vd = &(iso9660->joliet);
                        skipsize = LOGICAL_BLOCK_SIZE * vd->location;
                        skipsize -= iso9660->current_position;
                        skipsize = __archive_read_skip(a, skipsize);
                        if (skipsize < 0)
                                return ((int)skipsize);
                        iso9660->current_position += skipsize;

                        block = __archive_read_ahead(a, vd->size, NULL);
                        if (block == NULL) {
                                archive_set_error(&a->archive,
                                    ARCHIVE_ERRNO_MISC,
                                    "Failed to read full block when scanning "
                                    "ISO9660 directory list");
                                return (ARCHIVE_FATAL);
                        }
                        seenJoliet = iso9660->seenJoliet;/* Save flag. */
                        iso9660->seenJoliet = 0;
                        file = parse_file_info(a, NULL, block);
                        if (file == NULL)
                                return (ARCHIVE_FATAL);
                        iso9660->seenJoliet = seenJoliet;
                }
                /* Store the root directory in the pending list. */
                add_entry(iso9660, file);
                if (iso9660->seenRockridge) {
                        a->archive.archive_format =
                            ARCHIVE_FORMAT_ISO9660_ROCKRIDGE;
                        a->archive.archive_format_name =
                            "ISO9660 with Rockridge extensions";
                }
                rd_r = read_entries(a);
                if (rd_r == ARCHIVE_FATAL)
                        return (ARCHIVE_FATAL);
        } else
                rd_r = ARCHIVE_OK;

        /* Get the next entry that appears after the current offset. */
        r = next_entry_seek(a, iso9660, &file);
        if (r != ARCHIVE_OK)
                return (r);

        iso9660->entry_bytes_remaining = file->size;
        iso9660->entry_sparse_offset = 0; /* Offset for sparse-file-aware clients. */

        if (file->offset + file->size > iso9660->volume_size) {
                archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
                    "File is beyond end-of-media: %s", file->name);
                iso9660->entry_bytes_remaining = 0;
                iso9660->entry_sparse_offset = 0;
                return (ARCHIVE_WARN);
        }

        /* Set up the entry structure with information about this entry. */
        archive_entry_set_mode(entry, file->mode);
        archive_entry_set_uid(entry, file->uid);
        archive_entry_set_gid(entry, file->gid);
        archive_entry_set_nlink(entry, file->nlinks);
        if (file->birthtime_is_set)
                archive_entry_set_birthtime(entry, file->birthtime, 0);
        else
                archive_entry_unset_birthtime(entry);
        archive_entry_set_mtime(entry, file->mtime, 0);
        archive_entry_set_ctime(entry, file->ctime, 0);
        archive_entry_set_atime(entry, file->atime, 0);
        /* N.B.: Rock Ridge supports 64-bit device numbers. */
        archive_entry_set_rdev(entry, (dev_t)file->rdev);
        archive_entry_set_size(entry, iso9660->entry_bytes_remaining);
        archive_string_empty(&iso9660->pathname);
        archive_entry_set_pathname(entry,
            build_pathname(&iso9660->pathname, file));
        if (file->symlink.s != NULL)
                archive_entry_copy_symlink(entry, file->symlink.s);

        /* Note: If the input isn't seekable, we can't rewind to
         * return the same body again, so if the next entry refers to
         * the same data, we have to return it as a hardlink to the
         * original entry. */
        if (file->number != -1 &&
            file->number == iso9660->previous_number) {
                archive_entry_set_hardlink(entry,
                    iso9660->previous_pathname.s);
                archive_entry_unset_size(entry);
                iso9660->entry_bytes_remaining = 0;
                iso9660->entry_sparse_offset = 0;
                return (ARCHIVE_OK);
        }

        /* Except for the hardlink case above, if the offset of the
         * next entry is before our current position, we can't seek
         * backwards to extract it, so issue a warning.  Note that
         * this can only happen if this entry was added to the heap
         * after we passed this offset, that is, only if the directory
         * mentioning this entry is later than the body of the entry.
         * Such layouts are very unusual; most ISO9660 writers lay out
         * and record all directory information first, then store
         * all file bodies. */
        /* TODO: Someday, libarchive's I/O core will support optional
         * seeking.  When that day comes, this code should attempt to
         * seek and only return the error if the seek fails.  That
         * will give us support for whacky ISO images that require
         * seeking while retaining the ability to read almost all ISO
         * images in a streaming fashion. */
        if ((file->mode & AE_IFMT) != AE_IFDIR &&
            file->offset < iso9660->current_position) {
                archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
                    "Ignoring out-of-order file @%x (%s) %jd < %jd",
                    file,
                    iso9660->pathname.s,
                    file->offset, iso9660->current_position);
                iso9660->entry_bytes_remaining = 0;
                iso9660->entry_sparse_offset = 0;
                return (ARCHIVE_WARN);
        }

        /* Initialize zisofs variables. */
        iso9660->entry_zisofs.pz = file->pz;
        if (file->pz) {
#ifdef HAVE_ZLIB_H
                struct zisofs  *zisofs;

                zisofs = &iso9660->entry_zisofs;
                zisofs->initialized = 0;
                zisofs->pz_log2_bs = file->pz_log2_bs;
                zisofs->pz_uncompressed_size = file->pz_uncompressed_size;
                zisofs->pz_offset = 0;
                zisofs->header_avail = 0;
                zisofs->header_passed = 0;
                zisofs->block_pointers_avail = 0;
#endif
                archive_entry_set_size(entry, file->pz_uncompressed_size);
        }

        iso9660->previous_number = file->number;
        archive_strcpy(&iso9660->previous_pathname, iso9660->pathname.s);

        /* Reset entry_bytes_remaining if the file is multi extent. */
        iso9660->entry_content = file->contents.first;
        if (iso9660->entry_content != NULL)
                iso9660->entry_bytes_remaining = iso9660->entry_content->size;

        if (archive_entry_filetype(entry) == AE_IFDIR) {
                /* Overwrite nlinks by proper link number which is
                 * calculated from number of sub directories. */
                archive_entry_set_nlink(entry, 2 + file->subdirs);
                /* Directory data has been read completely. */
                iso9660->entry_bytes_remaining = 0;
                iso9660->entry_sparse_offset = 0;
                file->exposed = 1;
        }

        if (rd_r != ARCHIVE_OK)
                return (rd_r);
        return (ARCHIVE_OK);
}

static int
archive_read_format_iso9660_read_data_skip(struct archive_read *a)
{
        /* Because read_next_header always does an explicit skip
         * to the next entry, we don't need to do anything here. */
        (void)a; /* UNUSED */
        return (ARCHIVE_OK);
}

#ifdef HAVE_ZLIB_H

static int
zisofs_read_data(struct archive_read *a,
    const void **buff, size_t *size, off_t *offset)
{
        struct iso9660 *iso9660;
        struct zisofs  *zisofs;
        const unsigned char *p;
        size_t avail;
        ssize_t bytes_read;
        size_t uncompressed_size;
        int r;

        iso9660 = (struct iso9660 *)(a->format->data);
        zisofs = &iso9660->entry_zisofs;

        p = __archive_read_ahead(a, 1, &bytes_read);
        if (bytes_read <= 0) {
                archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
                    "Truncated zisofs file body");
                return (ARCHIVE_FATAL);
        }
        if (bytes_read > iso9660->entry_bytes_remaining)
                bytes_read = iso9660->entry_bytes_remaining;
        avail = bytes_read;
        uncompressed_size = 0;

        if (!zisofs->initialized) {
                size_t ceil, xsize;

                /* Allocate block pointers buffer. */
                ceil = (zisofs->pz_uncompressed_size +
                        (1LL << zisofs->pz_log2_bs) - 1)
                        >> zisofs->pz_log2_bs;
                xsize = (ceil + 1) * 4;
                if (zisofs->block_pointers_alloc < xsize) {
                        size_t alloc;

                        if (zisofs->block_pointers != NULL)
                                free(zisofs->block_pointers);
                        alloc = ((xsize >> 10) + 1) << 10;
                        zisofs->block_pointers = malloc(alloc);
                        if (zisofs->block_pointers == NULL) {
                                archive_set_error(&a->archive, ENOMEM,
                                    "No memory for zisofs decompression");
                                return (ARCHIVE_FATAL);
                        }
                        zisofs->block_pointers_alloc = alloc;
                }
                zisofs->block_pointers_size = xsize;

                /* Allocate uncompressed data buffer. */
                xsize = 1UL << zisofs->pz_log2_bs;
                if (zisofs->uncompressed_buffer_size < xsize) {
                        if (zisofs->uncompressed_buffer != NULL)
                                free(zisofs->uncompressed_buffer);
                        zisofs->uncompressed_buffer = malloc(xsize);
                        if (zisofs->uncompressed_buffer == NULL) {
                                archive_set_error(&a->archive, ENOMEM,
                                    "No memory for zisofs decompression");
                                return (ARCHIVE_FATAL);
                        }
                }
                zisofs->uncompressed_buffer_size = xsize;

                /*
                 * Read the file header, and check the magic code of zisofs.
                 */
                if (zisofs->header_avail < sizeof(zisofs->header)) {
                        xsize = sizeof(zisofs->header) - zisofs->header_avail;
                        if (avail < xsize)
                                xsize = avail;
                        memcpy(zisofs->header + zisofs->header_avail, p, xsize);
                        zisofs->header_avail += xsize;
                        avail -= xsize;
                        p += xsize;
                }
                if (!zisofs->header_passed &&
                    zisofs->header_avail == sizeof(zisofs->header)) {
                        int err = 0;

                        if (memcmp(zisofs->header, zisofs_magic,
                            sizeof(zisofs_magic)) != 0)
                                err = 1;
                        if (archive_le32dec(zisofs->header + 8)
                            != zisofs->pz_uncompressed_size)
                                err = 1;
                        if (zisofs->header[12] != 4)
                                err = 1;
                        if (zisofs->header[13] != zisofs->pz_log2_bs)
                                err = 1;
                        if (err) {
                                archive_set_error(&a->archive,
                                    ARCHIVE_ERRNO_FILE_FORMAT,
                                    "Illegal zisofs file body");
                                return (ARCHIVE_FATAL);
                        }
                        zisofs->header_passed = 1;
                }
                /*
                 * Read block pointers.
                 */
                if (zisofs->header_passed &&
                    zisofs->block_pointers_avail < zisofs->block_pointers_size) {
                        xsize = zisofs->block_pointers_size
                            - zisofs->block_pointers_avail;
                        if (avail < xsize)
                                xsize = avail;
                        memcpy(zisofs->block_pointers
                            + zisofs->block_pointers_avail, p, xsize);
                        zisofs->block_pointers_avail += xsize;
                        avail -= xsize;
                        p += xsize;
                        if (zisofs->block_pointers_avail
                            == zisofs->block_pointers_size) {
                                /* We've got all block pointers and initialize
                                 * related variables.   */
                                zisofs->block_off = 0;
                                zisofs->block_avail = 0;
                                /* Complete a initialization */
                                zisofs->initialized = 1;
                        }
                }

                if (!zisofs->initialized)
                        goto next_data; /* We need more datas. */
        }

        /*
         * Get block offsets from block pointers.
         */
        if (zisofs->block_avail == 0) {
                uint32_t bst, bed;

                if (zisofs->block_off + 4 >= zisofs->block_pointers_size) {
                        /* There isn't a pair of offsets. */
                        archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
                            "Illegal zisofs block pointers");
                        return (ARCHIVE_FATAL);
                }
                bst = archive_le32dec(zisofs->block_pointers + zisofs->block_off);
                if (bst != zisofs->pz_offset + (bytes_read - avail)) {
                        /* TODO: Should we seek offset of current file by bst ? */
                        archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
                            "Illegal zisofs block pointers(cannot seek)");
                        return (ARCHIVE_FATAL);
                }
                bed = archive_le32dec(
                    zisofs->block_pointers + zisofs->block_off + 4);
                if (bed < bst) {
                        archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
                            "Illegal zisofs block pointers");
                        return (ARCHIVE_FATAL);
                }
                zisofs->block_avail = bed - bst;
                zisofs->block_off += 4;

                /* Initialize compression library for new block. */
                if (zisofs->stream_valid)
                        r = inflateReset(&zisofs->stream);
                else
                        r = inflateInit(&zisofs->stream);
                if (r != Z_OK) {
                        archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
                            "Can't initialize zisofs decompression.");
                        return (ARCHIVE_FATAL);
                }
                zisofs->stream_valid = 1;
                zisofs->stream.total_in = 0;
                zisofs->stream.total_out = 0;
        }

        /*
         * Make uncompressed datas.
         */
        if (zisofs->block_avail == 0) {
                memset(zisofs->uncompressed_buffer, 0,
                    zisofs->uncompressed_buffer_size);
                uncompressed_size = zisofs->uncompressed_buffer_size;
        } else {
                zisofs->stream.next_in = (Bytef *)(uintptr_t)(const void *)p;
                if (avail > zisofs->block_avail)
                        zisofs->stream.avail_in = zisofs->block_avail;
                else
                        zisofs->stream.avail_in = avail;
                zisofs->stream.next_out = zisofs->uncompressed_buffer;
                zisofs->stream.avail_out = zisofs->uncompressed_buffer_size;

                r = inflate(&zisofs->stream, 0);
                switch (r) {
                case Z_OK: /* Decompressor made some progress.*/
                case Z_STREAM_END: /* Found end of stream. */
                        break;
                default:
                        archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
                            "zisofs decompression failed (%d)", r);
                        return (ARCHIVE_FATAL);
                }
                uncompressed_size =
                    zisofs->uncompressed_buffer_size - zisofs->stream.avail_out;
                avail -= zisofs->stream.next_in - p;
                zisofs->block_avail -= zisofs->stream.next_in - p;
        }
next_data:
        bytes_read -= avail;
        *buff = zisofs->uncompressed_buffer;
        *size = uncompressed_size;
        *offset = iso9660->entry_sparse_offset;
        iso9660->entry_sparse_offset += uncompressed_size;
        iso9660->entry_bytes_remaining -= bytes_read;
        iso9660->current_position += bytes_read;
        zisofs->pz_offset += bytes_read;
        __archive_read_consume(a, bytes_read);

        return (ARCHIVE_OK);
}

#else /* HAVE_ZLIB_H */

static int
zisofs_read_data(struct archive_read *a,
    const void **buff, size_t *size, off_t *offset)
{

        (void)buff;/* UNUSED */
        (void)size;/* UNUSED */
        (void)offset;/* UNUSED */
        archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
            "zisofs is not supported on this platform.");
        return (ARCHIVE_FAILED);
}

#endif /* HAVE_ZLIB_H */

static int
archive_read_format_iso9660_read_data(struct archive_read *a,
    const void **buff, size_t *size, off_t *offset)
{
        ssize_t bytes_read;
        struct iso9660 *iso9660;

        iso9660 = (struct iso9660 *)(a->format->data);
        if (iso9660->entry_bytes_remaining <= 0) {
                if (iso9660->entry_content != NULL)
                        iso9660->entry_content = iso9660->entry_content->next;
                if (iso9660->entry_content == NULL) {
                        *buff = NULL;
                        *size = 0;
                        *offset = iso9660->entry_sparse_offset;
                        return (ARCHIVE_EOF);
                }
                /* Seek forward to the start of the entry. */
                if (iso9660->current_position < iso9660->entry_content->offset) {
                        int64_t step;

                        step = iso9660->entry_content->offset -
                            iso9660->current_position;
                        step = __archive_read_skip(a, step);
                        if (step < 0)
                                return ((int)step);
                        iso9660->current_position =
                            iso9660->entry_content->offset;
                }
                if (iso9660->entry_content->offset < iso9660->current_position) {
                        archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
                            "Ignoring out-of-order file (%s) %jd < %jd",
                            iso9660->pathname.s,
                            iso9660->entry_content->offset,
                            iso9660->current_position);
                        *buff = NULL;
                        *size = 0;
                        *offset = iso9660->entry_sparse_offset;
                        return (ARCHIVE_WARN);
                }
                iso9660->entry_bytes_remaining = iso9660->entry_content->size;
        }
        if (iso9660->entry_zisofs.pz)
                return (zisofs_read_data(a, buff, size, offset));

        *buff = __archive_read_ahead(a, 1, &bytes_read);
        if (bytes_read == 0)
                archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
                    "Truncated input file");
        if (*buff == NULL)
                return (ARCHIVE_FATAL);
        if (bytes_read > iso9660->entry_bytes_remaining)
                bytes_read = iso9660->entry_bytes_remaining;
        *size = bytes_read;
        *offset = iso9660->entry_sparse_offset;
        iso9660->entry_sparse_offset += bytes_read;
        iso9660->entry_bytes_remaining -= bytes_read;
        iso9660->current_position += bytes_read;
        __archive_read_consume(a, bytes_read);
        return (ARCHIVE_OK);
}

static int
archive_read_format_iso9660_cleanup(struct archive_read *a)
{
        struct iso9660 *iso9660;
        int r = ARCHIVE_OK;

        iso9660 = (struct iso9660 *)(a->format->data);
        release_files(iso9660);
        free(iso9660->read_ce_req.reqs);
        archive_string_free(&iso9660->pathname);
        archive_string_free(&iso9660->previous_pathname);
        if (iso9660->pending_files.files)
                free(iso9660->pending_files.files);
        if (iso9660->re_dirs.files)
                free(iso9660->re_dirs.files);
        if (iso9660->cl_files.files)
                free(iso9660->cl_files.files);
#ifdef HAVE_ZLIB_H
        free(iso9660->entry_zisofs.uncompressed_buffer);
        free(iso9660->entry_zisofs.block_pointers);
        if (iso9660->entry_zisofs.stream_valid) {
                if (inflateEnd(&iso9660->entry_zisofs.stream) != Z_OK) {
                        archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
                            "Failed to clean up zlib decompressor");
                        r = ARCHIVE_FATAL;
                }
        }
#endif
        free(iso9660);
        (a->format->data) = NULL;
        return (r);
}

/*
 * This routine parses a single ISO directory record, makes sense
 * of any extensions, and stores the result in memory.
 */
static struct file_info *
parse_file_info(struct archive_read *a, struct file_info *parent,
    const unsigned char *isodirrec)
{
        struct iso9660 *iso9660;
        struct file_info *file;
        size_t name_len;
        const unsigned char *rr_start, *rr_end;
        const unsigned char *p;
        size_t dr_len;
        uint64_t fsize;
        int32_t location;
        int flags;

        iso9660 = (struct iso9660 *)(a->format->data);

        dr_len = (size_t)isodirrec[DR_length_offset];
        name_len = (size_t)isodirrec[DR_name_len_offset];
        location = archive_le32dec(isodirrec + DR_extent_offset);
        fsize = toi(isodirrec + DR_size_offset, DR_size_size);
        /* Sanity check that dr_len needs at least 34. */
        if (dr_len < 34) {
                archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
                    "Invalid length of directory record");
                return (NULL);
        }
        /* Sanity check that name_len doesn't exceed dr_len. */
        if (dr_len - 33 < name_len || name_len == 0) {
                archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
                    "Invalid length of file identifier");
                return (NULL);
        }
        /* Sanity check that location doesn't exceed volume block.
         * Don't check lower limit of location; it's possibility
         * the location has negative value when file type is symbolic
         * link or file size is zero. As far as I know latest mkisofs
         * do that.
         */
        if (location > 0 &&
            (location + ((fsize + iso9660->logical_block_size -1)
               / iso9660->logical_block_size)) >
              (unsigned int)iso9660->volume_block) {
                archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
                    "Invalid location of extent of file");
                return (NULL);
        }

        /* Create a new file entry and copy data from the ISO dir record. */
        file = (struct file_info *)malloc(sizeof(*file));
        if (file == NULL) {
                archive_set_error(&a->archive, ENOMEM,
                    "No memory for file entry");
                return (NULL);
        }
        memset(file, 0, sizeof(*file));
        file->parent = parent;
        file->offset = iso9660->logical_block_size * (uint64_t)location;
        file->size = fsize;
        file->mtime = isodate7(isodirrec + DR_date_offset);
        file->ctime = file->atime = file->mtime;

        p = isodirrec + DR_name_offset;
        /* Rockridge extensions (if any) follow name.  Compute this
         * before fidgeting the name_len below. */
        rr_start = p + name_len + (name_len & 1 ? 0 : 1);
        rr_end = isodirrec + dr_len;

        if (iso9660->seenJoliet) {
                /* Joliet names are max 64 chars (128 bytes) according to spec,
                 * but genisoimage/mkisofs allows recording longer Joliet
                 * names which are 103 UCS2 characters(206 bytes) by their
                 * option '-joliet-long'.
                 */
                wchar_t wbuff[103+1], *wp;
                const unsigned char *c;

                if (name_len > 206)
                        name_len = 206;
                /* convert BE UTF-16 to wchar_t */
                for (c = p, wp = wbuff;
                                c < (p + name_len) &&
                                wp < (wbuff + sizeof(wbuff)/sizeof(*wbuff) - 1);
                                c += 2) {
                        *wp++ = (((255 & (int)c[0]) << 8) | (255 & (int)c[1]));
                }
                *wp = L'\0';

#if 0 /* untested code, is it at all useful on Joliet? */
                /* trim trailing first version and dot from filename.
                 *
                 * Remember we where in UTF-16BE land!
                 * SEPARATOR 1 (.) and SEPARATOR 2 (;) are both
                 * 16 bits big endian characters on Joliet.
                 *
                 * TODO: sanitize filename?
                 *       Joliet allows any UCS-2 char except:
                 *       *, /, :, ;, ? and \.
                 */
                /* Chop off trailing ';1' from files. */
                if (*(wp-2) == ';' && *(wp-1) == '1') {
                        wp-=2;
                        *wp = L'\0';
                }

                /* Chop off trailing '.' from filenames. */
                if (*(wp-1) == '.')
                        *(--wp) = L'\0';
#endif

                /* store the result in the file name field. */
                archive_strappend_w_utf8(&file->name, wbuff);
        } else {
                /* Chop off trailing ';1' from files. */
                if (name_len > 2 && p[name_len - 2] == ';' &&
                                p[name_len - 1] == '1')
                        name_len -= 2;
                /* Chop off trailing '.' from filenames. */
                if (name_len > 1 && p[name_len - 1] == '.')
                        --name_len;

                archive_strncpy(&file->name, (const char *)p, name_len);
        }

        flags = isodirrec[DR_flags_offset];
        if (flags & 0x02)
                file->mode = AE_IFDIR | 0700;
        else
                file->mode = AE_IFREG | 0400;
        if (flags & 0x80)
                file->multi_extent = 1;
        else
                file->multi_extent = 0;
        /*
         * Use location for file number.
         * File number is treated as inode number to find out harlink
         * target. If Rockridge extensions is being used, file number
         * will be overwritten by FILE SERIAL NUMBER of RRIP "PX"
         * extension.
         * NOTE: Old mkisofs did not record that FILE SERIAL NUMBER
         * in ISO images.
         */
        if (file->size == 0 && location >= 0)
                /* If file->size is zero, its location points wrong place.
                 * Dot not use it for file number.
                 * When location has negative value, it can be used
                 * for file number.
                 */
                file->number = -1;
        else
                file->number = (int64_t)(uint32_t)location;

        /* Rockridge extensions overwrite information from above. */
        if (iso9660->opt_support_rockridge) {
                if (parent == NULL && rr_end - rr_start >= 7) {
                        p = rr_start;
                        if (p[0] == 'S' && p[1] == 'P'
                            && p[2] == 7 && p[3] == 1
                            && p[4] == 0xBE && p[5] == 0xEF) {
                                /*
                                 * SP extension stores the suspOffset
                                 * (Number of bytes to skip between
                                 * filename and SUSP records.)
                                 * It is mandatory by the SUSP standard
                                 * (IEEE 1281).
                                 *
                                 * It allows SUSP to coexist with
                                 * non-SUSP uses of the System
                                 * Use Area by placing non-SUSP data
                                 * before SUSP data.
                                 *
                                 * SP extension must be in the root
                                 * directory entry, disable all SUSP
                                 * processing if not found.
                                 */
                                iso9660->suspOffset = p[6];
                                iso9660->seenSUSP = 1;
                                rr_start += 7;
                        }
                }
                if (iso9660->seenSUSP) {
                        int r;

                        file->name_continues = 0;
                        file->symlink_continues = 0;
                        rr_start += iso9660->suspOffset;
                        r = parse_rockridge(a, file, rr_start, rr_end);
                        if (r != ARCHIVE_OK) {
                                free(file);
                                return (NULL);
                        }
                } else
                        /* If there isn't SUSP, disable parsing
                         * rock ridge extensions. */
                        iso9660->opt_support_rockridge = 0;
        }

        file->nlinks = 1;/* Reset nlink. we'll calculate it later. */
        /* Tell file's parent how many children that parent has. */
        if (parent != NULL && (flags & 0x02) && file->cl_offset == 0)
                parent->subdirs++;

#if DEBUG
        /* DEBUGGING: Warn about attributes I don't yet fully support. */
        if ((flags & ~0x02) != 0) {
                fprintf(stderr, "\n ** Unrecognized flag: ");
                dump_isodirrec(stderr, isodirrec);
                fprintf(stderr, "\n");
        } else if (toi(isodirrec + DR_volume_sequence_number_offset, 2) != 1) {
                fprintf(stderr, "\n ** Unrecognized sequence number: ");
                dump_isodirrec(stderr, isodirrec);
                fprintf(stderr, "\n");
        } else if (*(isodirrec + DR_file_unit_size_offset) != 0) {
                fprintf(stderr, "\n ** Unexpected file unit size: ");
                dump_isodirrec(stderr, isodirrec);
                fprintf(stderr, "\n");
        } else if (*(isodirrec + DR_interleave_offset) != 0) {
                fprintf(stderr, "\n ** Unexpected interleave: ");
                dump_isodirrec(stderr, isodirrec);
                fprintf(stderr, "\n");
        } else if (*(isodirrec + DR_ext_attr_length_offset) != 0) {
                fprintf(stderr, "\n ** Unexpected extended attribute length: ");
                dump_isodirrec(stderr, isodirrec);
                fprintf(stderr, "\n");
        }
#endif
        register_file(iso9660, file);
        return (file);
}

static int
parse_rockridge(struct archive_read *a, struct file_info *file,
    const unsigned char *p, const unsigned char *end)
{
        struct iso9660 *iso9660;

        iso9660 = (struct iso9660 *)(a->format->data);

        while (p + 4 <= end  /* Enough space for another entry. */
            && p[0] >= 'A' && p[0] <= 'Z' /* Sanity-check 1st char of name. */
            && p[1] >= 'A' && p[1] <= 'Z' /* Sanity-check 2nd char of name. */
            && p[2] >= 4 /* Sanity-check length. */
            && p + p[2] <= end) { /* Sanity-check length. */
                const unsigned char *data = p + 4;
                int data_length = p[2] - 4;
                int version = p[3];

                /*
                 * Yes, each 'if' here does test p[0] again.
                 * Otherwise, the fall-through handling to catch
                 * unsupported extensions doesn't work.
                 */
                switch(p[0]) {
                case 'C':
                        if (p[0] == 'C' && p[1] == 'E') {
                                if (version == 1 && data_length == 24) {
                                        /*
                                         * CE extension comprises:
                                         *   8 byte sector containing extension
                                         *   8 byte offset w/in above sector
                                         *   8 byte length of continuation
                                         */
                                        int32_t location =
                                            archive_le32dec(data);
                                        file->ce_offset =
                                            archive_le32dec(data+8);
                                        file->ce_size =
                                            archive_le32dec(data+16);
                                        if (register_CE(a, location, file)
                                            != ARCHIVE_OK)
                                                return (ARCHIVE_FATAL);
                                }
                                break;
                        }
                        if (p[0] == 'C' && p[1] == 'L') {
                                if (version == 1 && data_length == 8) {
                                        file->cl_offset = (uint64_t)
                                            iso9660->logical_block_size *
                                            (uint64_t)archive_le32dec(data);
                                        iso9660->seenRockridge = 1;
                                }
                                break;
                        }
                        /* FALLTHROUGH */
                case 'N':
                        if (p[0] == 'N' && p[1] == 'M') {
                                if (version == 1) {
                                        parse_rockridge_NM1(file,
                                            data, data_length);
                                        iso9660->seenRockridge = 1;
                                }
                                break;
                        }
                        /* FALLTHROUGH */
                case 'P':
                        if (p[0] == 'P' && p[1] == 'D') {
                                /*
                                 * PD extension is padding;
                                 * contents are always ignored.
                                 */
                                break;
                        }
                        if (p[0] == 'P' && p[1] == 'N') {
                                if (version == 1 && data_length == 16) {
                                        file->rdev = toi(data,4);
                                        file->rdev <<= 32;
                                        file->rdev |= toi(data + 8, 4);
                                        iso9660->seenRockridge = 1;
                                }
                                break;
                        }
                        if (p[0] == 'P' && p[1] == 'X') {
                                /*
                                 * PX extension comprises:
                                 *   8 bytes for mode,
                                 *   8 bytes for nlinks,
                                 *   8 bytes for uid,
                                 *   8 bytes for gid,
                                 *   8 bytes for inode.
                                 */
                                if (version == 1) {
                                        if (data_length >= 8)
                                                file->mode
                                                    = toi(data, 4);
                                        if (data_length >= 16)
                                                file->nlinks
                                                    = toi(data + 8, 4);
                                        if (data_length >= 24)
                                                file->uid
                                                    = toi(data + 16, 4);
                                        if (data_length >= 32)
                                                file->gid
                                                    = toi(data + 24, 4);
                                        if (data_length >= 40)
                                                file->number
                                                    = toi(data + 32, 4);
                                        iso9660->seenRockridge = 1;
                                }
                                break;
                        }
                        /* FALLTHROUGH */
                case 'R':
                        if (p[0] == 'R' && p[1] == 'E' && version == 1) {
                                file->re = 1;
                                iso9660->seenRockridge = 1;
                                break;
                        }
                        if (p[0] == 'R' && p[1] == 'R' && version == 1) {
                                /*
                                 * RR extension comprises:
                                 *    one byte flag value
                                 * This extension is obsolete,
                                 * so contents are always ignored.
                                 */
                                break;
                        }
                        /* FALLTHROUGH */
                case 'S':
                        if (p[0] == 'S' && p[1] == 'L') {
                                if (version == 1) {
                                        parse_rockridge_SL1(file,
                                            data, data_length);
                                        iso9660->seenRockridge = 1;
                                }
                                break;
                        }
                        if (p[0] == 'S' && p[1] == 'T'
                            && data_length == 0 && version == 1) {
                                /*
                                 * ST extension marks end of this
                                 * block of SUSP entries.
                                 *
                                 * It allows SUSP to coexist with
                                 * non-SUSP uses of the System
                                 * Use Area by placing non-SUSP data
                                 * after SUSP data.
                                 */
                                iso9660->seenSUSP = 0;
                                iso9660->seenRockridge = 0;
                                return (ARCHIVE_OK);
                        }
                case 'T':
                        if (p[0] == 'T' && p[1] == 'F') {
                                if (version == 1) {
                                        parse_rockridge_TF1(file,
                                            data, data_length);
                                        iso9660->seenRockridge = 1;
                                }
                                break;
                        }
                        /* FALLTHROUGH */
                case 'Z':
                        if (p[0] == 'Z' && p[1] == 'F') {
                                if (version == 1)
                                        parse_rockridge_ZF1(file,
                                            data, data_length);
                                break;
                        }
                        /* FALLTHROUGH */
                default:
                        /* The FALLTHROUGHs above leave us here for
                         * any unsupported extension. */
                        break;
                }



                p += p[2];
        }
        return (ARCHIVE_OK);
}

static int
register_CE(struct archive_read *a, int32_t location,
    struct file_info *file)
{
        struct iso9660 *iso9660;
        struct read_ce_queue *heap;
        struct read_ce_req *p;
        uint64_t offset, parent_offset;
        int hole, parent;

        iso9660 = (struct iso9660 *)(a->format->data);
        offset = ((uint64_t)location) * (uint64_t)iso9660->logical_block_size;
        if (((file->mode & AE_IFMT) == AE_IFREG &&
            offset >= file->offset) ||
            offset < iso9660->current_position) {
                archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
                    "Invalid location in SUSP \"CE\" extension");
                return (ARCHIVE_FATAL);
        }

        /* Expand our CE list as necessary. */
        heap = &(iso9660->read_ce_req);
        if (heap->cnt >= heap->allocated) {
                int new_size;

                if (heap->allocated < 16)
                        new_size = 16;
                else
                        new_size = heap->allocated * 2;
                /* Overflow might keep us from growing the list. */
                if (new_size <= heap->allocated)
                        __archive_errx(1, "Out of memory");
                p = malloc(new_size * sizeof(p[0]));
                if (p == NULL)
                        __archive_errx(1, "Out of memory");
                if (heap->reqs != NULL) {
                        memcpy(p, heap->reqs, heap->cnt * sizeof(*p));
                        free(heap->reqs);
                }
                heap->reqs = p;
                heap->allocated = new_size;
        }

        /*
         * Start with hole at end, walk it up tree to find insertion point.
         */
        hole = heap->cnt++;
        while (hole > 0) {
                parent = (hole - 1)/2;
                parent_offset = heap->reqs[parent].offset;
                if (offset >= parent_offset) {
                        heap->reqs[hole].offset = offset;
                        heap->reqs[hole].file = file;
                        return (ARCHIVE_OK);
                }
                // Move parent into hole <==> move hole up tree.
                heap->reqs[hole] = heap->reqs[parent];
                hole = parent;
        }
        heap->reqs[0].offset = offset;
        heap->reqs[0].file = file;
        return (ARCHIVE_OK);
}

static void
next_CE(struct read_ce_queue *heap)
{
        uint64_t a_offset, b_offset, c_offset;
        int a, b, c;
        struct read_ce_req tmp;

        if (heap->cnt < 1)
                return;

        /*
         * Move the last item in the heap to the root of the tree
         */
        heap->reqs[0] = heap->reqs[--(heap->cnt)];

        /*
         * Rebalance the heap.
         */
        a = 0; // Starting element and its offset
        a_offset = heap->reqs[a].offset;
        for (;;) {
                b = a + a + 1; // First child
                if (b >= heap->cnt)
                        return;
                b_offset = heap->reqs[b].offset;
                c = b + 1; // Use second child if it is smaller.
                if (c < heap->cnt) {
                        c_offset = heap->reqs[c].offset;
                        if (c_offset < b_offset) {
                                b = c;
                                b_offset = c_offset;
                        }
                }
                if (a_offset <= b_offset)
                        return;
                tmp = heap->reqs[a];
                heap->reqs[a] = heap->reqs[b];
                heap->reqs[b] = tmp;
                a = b;
        }
}


static int
read_CE(struct archive_read *a, struct iso9660 *iso9660)
{
        struct read_ce_queue *heap;
        const unsigned char *b, *p, *end;
        struct file_info *file;
        size_t step;
        int r;

        /* Read data which RRIP "CE" extension points. */
        heap = &(iso9660->read_ce_req);
        step = iso9660->logical_block_size;
        while (heap->cnt &&
            heap->reqs[0].offset == iso9660->current_position) {
                b = __archive_read_ahead(a, step, NULL);
                if (b == NULL) {
                        archive_set_error(&a->archive,
                            ARCHIVE_ERRNO_MISC,
                            "Failed to read full block when scanning "
                            "ISO9660 directory list");
                        return (ARCHIVE_FATAL);
                }
                do {
                        file = heap->reqs[0].file;
                        p = b + file->ce_offset;
                        end = p + file->ce_size;
                        next_CE(heap);
                        r = parse_rockridge(a, file, p, end);
                        if (r != ARCHIVE_OK)
                                return (ARCHIVE_FATAL);
                } while (heap->cnt &&
                    heap->reqs[0].offset == iso9660->current_position);
                /* NOTE: Do not move this consume's code to fron of
                 * do-while loop. Registration of nested CE extension
                 * might cause error because of current position. */
                __archive_read_consume(a, step);
                iso9660->current_position += step;
        }
        return (ARCHIVE_OK);
}

static void
parse_rockridge_NM1(struct file_info *file,
                    const unsigned char *data, int data_length)
{
        if (!file->name_continues)
                archive_string_empty(&file->name);
        file->name_continues = 0;
        if (data_length < 1)
                return;
        /*
         * NM version 1 extension comprises:
         *   1 byte flag, value is one of:
         *     = 0: remainder is name
         *     = 1: remainder is name, next NM entry continues name
         *     = 2: "."
         *     = 4: ".."
         *     = 32: Implementation specific
         *     All other values are reserved.
         */
        switch(data[0]) {
        case 0:
                if (data_length < 2)
                        return;
                archive_strncat(&file->name, (const char *)data + 1, data_length - 1);
                break;
        case 1:
                if (data_length < 2)
                        return;
                archive_strncat(&file->name, (const char *)data + 1, data_length - 1);
                file->name_continues = 1;
                break;
        case 2:
                archive_strcat(&file->name, ".");
                break;
        case 4:
                archive_strcat(&file->name, "..");
                break;
        default:
                return;
        }

}

static void
parse_rockridge_TF1(struct file_info *file, const unsigned char *data,
    int data_length)
{
        char flag;
        /*
         * TF extension comprises:
         *   one byte flag
         *   create time (optional)
         *   modify time (optional)
         *   access time (optional)
         *   attribute time (optional)
         *  Time format and presence of fields
         *  is controlled by flag bits.
         */
        if (data_length < 1)
                return;
        flag = data[0];
        ++data;
        --data_length;
        if (flag & 0x80) {
                /* Use 17-byte time format. */
                if ((flag & 1) && data_length >= 17) {
                        /* Create time. */
                        file->birthtime_is_set = 1;
                        file->birthtime = isodate17(data);
                        data += 17;
                        data_length -= 17;
                }
                if ((flag & 2) && data_length >= 17) {
                        /* Modify time. */
                        file->mtime = isodate17(data);
                        data += 17;
                        data_length -= 17;
                }
                if ((flag & 4) && data_length >= 17) {
                        /* Access time. */
                        file->atime = isodate17(data);
                        data += 17;
                        data_length -= 17;
                }
                if ((flag & 8) && data_length >= 17) {
                        /* Attribute change time. */
                        file->ctime = isodate17(data);
                }
        } else {
                /* Use 7-byte time format. */
                if ((flag & 1) && data_length >= 7) {
                        /* Create time. */
                        file->birthtime_is_set = 1;
                        file->birthtime = isodate7(data);
                        data += 7;
                        data_length -= 7;
                }
                if ((flag & 2) && data_length >= 7) {
                        /* Modify time. */
                        file->mtime = isodate7(data);
                        data += 7;
                        data_length -= 7;
                }
                if ((flag & 4) && data_length >= 7) {
                        /* Access time. */
                        file->atime = isodate7(data);
                        data += 7;
                        data_length -= 7;
                }
                if ((flag & 8) && data_length >= 7) {
                        /* Attribute change time. */
                        file->ctime = isodate7(data);
                }
        }
}

static void
parse_rockridge_SL1(struct file_info *file, const unsigned char *data,
    int data_length)
{
        const char *separator = "";

        if (!file->symlink_continues || file->symlink.length < 1)
                archive_string_empty(&file->symlink);
        else if (!file->symlink_continues &&
            file->symlink.s[file->symlink.length - 1] != '/')
                separator = "/";
        file->symlink_continues = 0;

        /*
         * Defined flag values:
         *  0: This is the last SL record for this symbolic link
         *  1: this symbolic link field continues in next SL entry
         *  All other values are reserved.
         */
        if (data_length < 1)
                return;
        switch(*data) {
        case 0:
                break;
        case 1:
                file->symlink_continues = 1;
                break;
        default:
                return;
        }
        ++data;  /* Skip flag byte. */
        --data_length;

        /*
         * SL extension body stores "components".
         * Basically, this is a complicated way of storing
         * a POSIX path.  It also interferes with using
         * symlinks for storing non-path data. <sigh>
         *
         * Each component is 2 bytes (flag and length)
         * possibly followed by name data.
         */
        while (data_length >= 2) {
                unsigned char flag = *data++;
                unsigned char nlen = *data++;
                data_length -= 2;

                archive_strcat(&file->symlink, separator);
                separator = "/";

                switch(flag) {
                case 0: /* Usual case, this is text. */
                        if (data_length < nlen)
                                return;
                        archive_strncat(&file->symlink,
                            (const char *)data, nlen);
                        break;
                case 0x01: /* Text continues in next component. */
                        if (data_length < nlen)
                                return;
                        archive_strncat(&file->symlink,
                            (const char *)data, nlen);
                        separator = "";
                        break;
                case 0x02: /* Current dir. */
                        archive_strcat(&file->symlink, ".");
                        break;
                case 0x04: /* Parent dir. */
                        archive_strcat(&file->symlink, "..");
                        break;
                case 0x08: /* Root of filesystem. */
                        archive_strcat(&file->symlink, "/");
                        separator = "";
                        break;
                case 0x10: /* Undefined (historically "volume root" */
                        archive_string_empty(&file->symlink);
                        archive_strcat(&file->symlink, "ROOT");
                        break;
                case 0x20: /* Undefined (historically "hostname") */
                        archive_strcat(&file->symlink, "hostname");
                        break;
                default:
                        /* TODO: issue a warning ? */
                        return;
                }
                data += nlen;
                data_length -= nlen;
        }
}

static void
parse_rockridge_ZF1(struct file_info *file, const unsigned char *data,
    int data_length)
{

        if (data[0] == 0x70 && data[1] == 0x7a && data_length == 12) {
                /* paged zlib */
                file->pz = 1;
                file->pz_log2_bs = data[3];
                file->pz_uncompressed_size = archive_le32dec(&data[4]);
        }
}

static void
register_file(struct iso9660 *iso9660, struct file_info *file)
{

        file->use_next = iso9660->use_files;
        iso9660->use_files = file;
}

static void
release_files(struct iso9660 *iso9660)
{
        struct content *con, *connext;
        struct file_info *file;

        file = iso9660->use_files;
        while (file != NULL) {
                struct file_info *next = file->use_next;

                archive_string_free(&file->name);
                archive_string_free(&file->symlink);
                con = file->contents.first;
                while (con != NULL) {
                        connext = con->next;
                        free(con);
                        con = connext;
                }
                free(file);
                file = next;
        }
}

static int
next_entry_seek(struct archive_read *a, struct iso9660 *iso9660,
    struct file_info **pfile)
{
        struct file_info *file;

        *pfile = file = next_cache_entry(iso9660);
        if (file == NULL)
                return (ARCHIVE_EOF);

        /* Don't waste time seeking for zero-length bodies. */
        if (file->size == 0)
                file->offset = iso9660->current_position;

        /* Seek forward to the start of the entry. */
        if (iso9660->current_position < file->offset) {
                int64_t step;

                step = file->offset - iso9660->current_position;
                step = __archive_read_skip(a, step);
                if (step < 0)
                        return ((int)step);
                iso9660->current_position = file->offset;
        }

        /* We found body of file; handle it now. */
        return (ARCHIVE_OK);
}

static struct file_info *
next_cache_entry(struct iso9660 *iso9660)
{
        struct file_info *file;
        struct {
                struct file_info        *first;
                struct file_info        **last;
        }       empty_files;
        int64_t number;
        int count;

        file = cache_get_entry(iso9660);
        if (file != NULL) {
                while (file->parent != NULL && !file->parent->exposed) {
                        /* If file's parent is not exposed, it's moved
                         * to next entry of its parent. */
                        cache_add_to_next_of_parent(iso9660, file);
                        file = cache_get_entry(iso9660);
                }
                return (file);
        }

        file = next_entry(iso9660);
        if (file == NULL)
                return (NULL);

        if ((file->mode & AE_IFMT) != AE_IFREG || file->number == -1)
                return (file);

        count = 0;
        number = file->number;
        iso9660->cache_files.first = NULL;
        iso9660->cache_files.last = &(iso9660->cache_files.first);
        empty_files.first = NULL;
        empty_files.last = &empty_files.first;
        /* Collect files which has the same file serial number.
         * Peek pending_files so that file which number is different
         * is not put bak. */
        while (iso9660->pending_files.used > 0 &&
            (iso9660->pending_files.files[0]->number == -1 ||
             iso9660->pending_files.files[0]->number == number)) {
                if (file->number == -1) {
                        /* This file has the same offset
                         * but it's wrong offset which empty files
                         * and symlink files have.
                         * NOTE: This wrong offse was recorded by
                         * old mkisofs utility. If ISO images is
                         * created by latest mkisofs, this does not
                         * happen.
                         */
                        file->next = NULL;
                        *empty_files.last = file;
                        empty_files.last = &(file->next);
                } else {
                        count++;
                        cache_add_entry(iso9660, file);
                }
                file = next_entry(iso9660);
        }

        if (count == 0)
                return (file);
        if (file->number == -1) {
                file->next = NULL;
                *empty_files.last = file;
                empty_files.last = &(file->next);
        } else {
                count++;
                cache_add_entry(iso9660, file);
        }

        if (count > 1) {
                /* The count is the same as number of hardlink,
                 * so much so that each nlinks of files in cache_file
                 * is overwritten by value of the count.
                 */
                for (file = iso9660->cache_files.first;
                    file != NULL; file = file->next)
                        file->nlinks = count;
        }
        /* If there are empty files, that files are added
         * to the tail of the cache_files. */
        if (empty_files.first != NULL) {
                *iso9660->cache_files.last = empty_files.first;
                iso9660->cache_files.last = empty_files.last;
        }
        return (cache_get_entry(iso9660));
}

static inline void
cache_add_entry(struct iso9660 *iso9660, struct file_info *file)
{
        file->next = NULL;
        *iso9660->cache_files.last = file;
        iso9660->cache_files.last = &(file->next);
}

static inline void
cache_add_to_next_of_parent(struct iso9660 *iso9660, struct file_info *file)
{
        file->next = file->parent->next;
        file->parent->next = file;
        if (iso9660->cache_files.last == &(file->parent->next))
                iso9660->cache_files.last = &(file->next);
}

static inline struct file_info *
cache_get_entry(struct iso9660 *iso9660)
{
        struct file_info *file;

        if ((file = iso9660->cache_files.first) != NULL) {
                iso9660->cache_files.first = file->next;
                if (iso9660->cache_files.first == NULL)
                        iso9660->cache_files.last = &(iso9660->cache_files.first);
        }
        return (file);
}

static void
heap_add_entry(struct heap_queue *heap, struct file_info *file, uint64_t key)
{
        uint64_t file_key, parent_key;
        int hole, parent;

        /* Expand our pending files list as necessary. */
        if (heap->used >= heap->allocated) {
                struct file_info **new_pending_files;
                int new_size = heap->allocated * 2;

                if (heap->allocated < 1024)
                        new_size = 1024;
                /* Overflow might keep us from growing the list. */
                if (new_size <= heap->allocated)
                        __archive_errx(1, "Out of memory");
                new_pending_files = (struct file_info **)
                    malloc(new_size * sizeof(new_pending_files[0]));
                if (new_pending_files == NULL)
                        __archive_errx(1, "Out of memory");
                memcpy(new_pending_files, heap->files,
                    heap->allocated * sizeof(new_pending_files[0]));
                if (heap->files != NULL)
                        free(heap->files);
                heap->files = new_pending_files;
                heap->allocated = new_size;
        }

        file_key = file->key = key;

        /*
         * Start with hole at end, walk it up tree to find insertion point.
         */
        hole = heap->used++;
        while (hole > 0) {
                parent = (hole - 1)/2;
                parent_key = heap->files[parent]->key;
                if (file_key >= parent_key) {
                        heap->files[hole] = file;
                        return;
                }
                // Move parent into hole <==> move hole up tree.
                heap->files[hole] = heap->files[parent];
                hole = parent;
        }
        heap->files[0] = file;
}

static struct file_info *
heap_get_entry(struct heap_queue *heap)
{
        uint64_t a_key, b_key, c_key;
        int a, b, c;
        struct file_info *r, *tmp;

        if (heap->used < 1)
                return (NULL);

        /*
         * The first file in the list is the earliest; we'll return this.
         */
        r = heap->files[0];

        /*
         * Move the last item in the heap to the root of the tree
         */
        heap->files[0] = heap->files[--(heap->used)];

        /*
         * Rebalance the heap.
         */
        a = 0; // Starting element and its heap key
        a_key = heap->files[a]->key;
        for (;;) {
                b = a + a + 1; // First child
                if (b >= heap->used)
                        return (r);
                b_key = heap->files[b]->key;
                c = b + 1; // Use second child if it is smaller.
                if (c < heap->used) {
                        c_key = heap->files[c]->key;
                        if (c_key < b_key) {
                                b = c;
                                b_key = c_key;
                        }
                }
                if (a_key <= b_key)
                        return (r);
                tmp = heap->files[a];
                heap->files[a] = heap->files[b];
                heap->files[b] = tmp;
                a = b;
        }
}

static unsigned int
toi(const void *p, int n)
{
        const unsigned char *v = (const unsigned char *)p;
        if (n > 1)
                return v[0] + 256 * toi(v + 1, n - 1);
        if (n == 1)
                return v[0];
        return (0);
}

static time_t
isodate7(const unsigned char *v)
{
        struct tm tm;
        int offset;
        memset(&tm, 0, sizeof(tm));
        tm.tm_year = v[0];
        tm.tm_mon = v[1] - 1;
        tm.tm_mday = v[2];
        tm.tm_hour = v[3];
        tm.tm_min = v[4];
        tm.tm_sec = v[5];
        /* v[6] is the signed timezone offset, in 1/4-hour increments. */
        offset = ((const signed char *)v)[6];
        if (offset > -48 && offset < 52) {
                tm.tm_hour -= offset / 4;
                tm.tm_min -= (offset % 4) * 15;
        }
        return (time_from_tm(&tm));
}

static time_t
isodate17(const unsigned char *v)
{
        struct tm tm;
        int offset;
        memset(&tm, 0, sizeof(tm));
        tm.tm_year = (v[0] - '0') * 1000 + (v[1] - '0') * 100
            + (v[2] - '0') * 10 + (v[3] - '0')
            - 1900;
        tm.tm_mon = (v[4] - '0') * 10 + (v[5] - '0');
        tm.tm_mday = (v[6] - '0') * 10 + (v[7] - '0');
        tm.tm_hour = (v[8] - '0') * 10 + (v[9] - '0');
        tm.tm_min = (v[10] - '0') * 10 + (v[11] - '0');
        tm.tm_sec = (v[12] - '0') * 10 + (v[13] - '0');
        /* v[16] is the signed timezone offset, in 1/4-hour increments. */
        offset = ((const signed char *)v)[16];
        if (offset > -48 && offset < 52) {
                tm.tm_hour -= offset / 4;
                tm.tm_min -= (offset % 4) * 15;
        }
        return (time_from_tm(&tm));
}

static time_t
time_from_tm(struct tm *t)
{
#if HAVE_TIMEGM
        /* Use platform timegm() if available. */
        return (timegm(t));
#else
        /* Else use direct calculation using POSIX assumptions. */
        /* First, fix up tm_yday based on the year/month/day. */
        mktime(t);
        /* Then we can compute timegm() from first principles. */
        return (t->tm_sec + t->tm_min * 60 + t->tm_hour * 3600
            + t->tm_yday * 86400 + (t->tm_year - 70) * 31536000
            + ((t->tm_year - 69) / 4) * 86400 -
            ((t->tm_year - 1) / 100) * 86400
            + ((t->tm_year + 299) / 400) * 86400);
#endif
}

static const char *
build_pathname(struct archive_string *as, struct file_info *file)
{
        if (file->parent != NULL && archive_strlen(&file->parent->name) > 0) {
                build_pathname(as, file->parent);
                archive_strcat(as, "/");
        }
        if (archive_strlen(&file->name) == 0)
                archive_strcat(as, ".");
        else
                archive_string_concat(as, &file->name);
        return (as->s);
}

#if DEBUG
static void
dump_isodirrec(FILE *out, const unsigned char *isodirrec)
{
        fprintf(out, " l %d,",
            toi(isodirrec + DR_length_offset, DR_length_size));
        fprintf(out, " a %d,",
            toi(isodirrec + DR_ext_attr_length_offset, DR_ext_attr_length_size));
        fprintf(out, " ext 0x%x,",
            toi(isodirrec + DR_extent_offset, DR_extent_size));
        fprintf(out, " s %d,",
            toi(isodirrec + DR_size_offset, DR_extent_size));
        fprintf(out, " f 0x%02x,",
            toi(isodirrec + DR_flags_offset, DR_flags_size));
        fprintf(out, " u %d,",
            toi(isodirrec + DR_file_unit_size_offset, DR_file_unit_size_size));
        fprintf(out, " ilv %d,",
            toi(isodirrec + DR_interleave_offset, DR_interleave_size));
        fprintf(out, " seq %d,",
            toi(isodirrec + DR_volume_sequence_number_offset, DR_volume_sequence_number_size));
        fprintf(out, " nl %d:",
            toi(isodirrec + DR_name_len_offset, DR_name_len_size));
        fprintf(out, " `%.*s'",
            toi(isodirrec + DR_name_len_offset, DR_name_len_size), isodirrec + DR_name_offset);
}
#endif