/*
 * Copyright (C) 2000, 2001, 2002, 2003
 *               Björn Englund <d4bjorn@dtek.chalmers.se>,
 *               Håkan Hjort <d95hjort@dtek.chalmers.se>
 *
 * This file is part of libdvdread.
 *
 * libdvdread is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * libdvdread is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with libdvdread; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include "config.h"

#include <stdio.h>
#include <stdlib.h>
#include <inttypes.h>
#include <string.h>

#include "bswap.h"
#include "dvdread/ifo_types.h"
#include "dvdread/ifo_read.h"
#include "dvdread/dvd_reader.h"
#include "dvdread_internal.h"
#include "dvdread/bitreader.h"

#ifndef DVD_BLOCK_LEN
#define DVD_BLOCK_LEN 2048
#endif

#ifndef NDEBUG
#define CHECK_ZERO0(arg)                                                \
  if(arg != 0) {                                                        \
    fprintf(stderr, "*** Zero check failed in %s:%i\n    for %s = 0x%x\n", \
            __FILE__, __LINE__, # arg, arg);                            \
  }
#define CHECK_ZERO(arg)                                                 \
  if(memcmp(my_friendly_zeros, &arg, sizeof(arg))) {                    \
    unsigned int i_CZ;                                                  \
    fprintf(stderr, "*** Zero check failed in %s:%i\n    for %s = 0x",  \
            __FILE__, __LINE__, # arg );                                \
    for(i_CZ = 0; i_CZ < sizeof(arg); i_CZ++)                           \
      fprintf(stderr, "%02x", *((uint8_t *)&arg + i_CZ));               \
    fprintf(stderr, "\n");                                              \
  }
static const uint8_t my_friendly_zeros[2048];
#else
#define CHECK_ZERO0(arg) (void)(arg)
#define CHECK_ZERO(arg) (void)(arg)
#endif


/* Prototypes for internal functions */
static int ifoRead_VMG(ifo_handle_t *ifofile);
static int ifoRead_VTS(ifo_handle_t *ifofile);
static int ifoRead_PGC(ifo_handle_t *ifofile, pgc_t *pgc, unsigned int offset);
static int ifoRead_PGC_COMMAND_TBL(ifo_handle_t *ifofile,
                                   pgc_command_tbl_t *cmd_tbl,
                                   unsigned int offset);
static int ifoRead_PGC_PROGRAM_MAP(ifo_handle_t *ifofile,
                                   pgc_program_map_t *program_map,
                                   unsigned int nr, unsigned int offset);
static int ifoRead_CELL_PLAYBACK_TBL(ifo_handle_t *ifofile,
                                     cell_playback_t *cell_playback,
                                     unsigned int nr, unsigned int offset);
static int ifoRead_CELL_POSITION_TBL(ifo_handle_t *ifofile,
                                     cell_position_t *cell_position,
                                     unsigned int nr, unsigned int offset);
static int ifoRead_VTS_ATTRIBUTES(ifo_handle_t *ifofile,
                                  vts_attributes_t *vts_attributes,
                                  unsigned int offset);
static int ifoRead_C_ADT_internal(ifo_handle_t *ifofile, c_adt_t *c_adt,
                                  unsigned int sector);
static int ifoRead_VOBU_ADMAP_internal(ifo_handle_t *ifofile,
                                       vobu_admap_t *vobu_admap,
                                       unsigned int sector);
static int ifoRead_PGCIT_internal(ifo_handle_t *ifofile, pgcit_t *pgcit,
                                  unsigned int offset);

static void ifoFree_PGC(pgc_t *pgc);
static void ifoFree_PGC_COMMAND_TBL(pgc_command_tbl_t *cmd_tbl);
static void ifoFree_PGCIT_internal(pgcit_t *pgcit);

static inline int DVDFileSeekForce_( dvd_file_t *dvd_file, uint32_t offset, int force_size ) {
  return (DVDFileSeekForce(dvd_file, (int)offset, force_size) == (int)offset);
}

static inline int DVDFileSeek_( dvd_file_t *dvd_file, uint32_t offset ) {
  return (DVDFileSeek(dvd_file, (int)offset) == (int)offset);
}

static void read_video_attr(video_attr_t *va) {
  getbits_state_t state;
  uint8_t buf[sizeof(video_attr_t)];

  memcpy(buf, va, sizeof(video_attr_t));
  if (!dvdread_getbits_init(&state, buf)) abort();
  va->mpeg_version = dvdread_getbits(&state, 2);
  va->video_format = dvdread_getbits(&state, 2);
  va->display_aspect_ratio = dvdread_getbits(&state, 2);
  va->permitted_df = dvdread_getbits(&state, 2);
  va->line21_cc_1 = dvdread_getbits(&state, 1);
  va->line21_cc_2 = dvdread_getbits(&state, 1);
  va->unknown1 = dvdread_getbits(&state, 1);
  va->bit_rate = dvdread_getbits(&state, 1);
  va->picture_size = dvdread_getbits(&state, 2);
  va->letterboxed = dvdread_getbits(&state, 1);
  va->film_mode = dvdread_getbits(&state, 1);
}

static void read_audio_attr(audio_attr_t *aa) {
  getbits_state_t state;
  uint8_t buf[sizeof(audio_attr_t)];

  memcpy(buf, aa, sizeof(audio_attr_t));
  if (!dvdread_getbits_init(&state, buf)) abort();
  aa->audio_format = dvdread_getbits(&state, 3);
  aa->multichannel_extension = dvdread_getbits(&state, 1);
  aa->lang_type = dvdread_getbits(&state, 2);
  aa->application_mode = dvdread_getbits(&state, 2);
  aa->quantization = dvdread_getbits(&state, 2);
  aa->sample_frequency = dvdread_getbits(&state, 2);
  aa->unknown1 = dvdread_getbits(&state, 1);
  aa->channels = dvdread_getbits(&state, 3);
  aa->lang_code = dvdread_getbits(&state, 16);
  aa->lang_extension = dvdread_getbits(&state, 8);
  aa->code_extension = dvdread_getbits(&state, 8);
  aa->unknown3 = dvdread_getbits(&state, 8);
  aa->app_info.karaoke.unknown4 = dvdread_getbits(&state, 1);
  aa->app_info.karaoke.channel_assignment = dvdread_getbits(&state, 3);
  aa->app_info.karaoke.version = dvdread_getbits(&state, 2);
  aa->app_info.karaoke.mc_intro = dvdread_getbits(&state, 1);
  aa->app_info.karaoke.mode = dvdread_getbits(&state, 1);
}

static void read_multichannel_ext(multichannel_ext_t *me) {
  getbits_state_t state;
  uint8_t buf[sizeof(multichannel_ext_t)];

  memcpy(buf, me, sizeof(multichannel_ext_t));
  if (!dvdread_getbits_init(&state, buf)) abort();
  me->zero1 = dvdread_getbits(&state, 7);
  me->ach0_gme = dvdread_getbits(&state, 1);
  me->zero2 = dvdread_getbits(&state, 7);
  me->ach1_gme = dvdread_getbits(&state, 1);
  me->zero3 = dvdread_getbits(&state, 4);
  me->ach2_gv1e = dvdread_getbits(&state, 1);
  me->ach2_gv2e = dvdread_getbits(&state, 1);
  me->ach2_gm1e = dvdread_getbits(&state, 1);
  me->ach2_gm2e = dvdread_getbits(&state, 1);
  me->zero4 = dvdread_getbits(&state, 4);
  me->ach3_gv1e = dvdread_getbits(&state, 1);
  me->ach3_gv2e = dvdread_getbits(&state, 1);
  me->ach3_gmAe = dvdread_getbits(&state, 1);
  me->ach3_se2e = dvdread_getbits(&state, 1);
  me->zero5 = dvdread_getbits(&state, 4);
  me->ach4_gv1e = dvdread_getbits(&state, 1);
  me->ach4_gv2e = dvdread_getbits(&state, 1);
  me->ach4_gmBe = dvdread_getbits(&state, 1);
  me->ach4_seBe = dvdread_getbits(&state, 1);
}

static void read_subp_attr(subp_attr_t *sa) {
  getbits_state_t state;
  uint8_t buf[sizeof(subp_attr_t)];

  memcpy(buf, sa, sizeof(subp_attr_t));
  if (!dvdread_getbits_init(&state, buf)) abort();
  sa->code_mode = dvdread_getbits(&state, 3);
  sa->zero1 = dvdread_getbits(&state, 3);
  sa->type = dvdread_getbits(&state, 2);
  sa->zero2 = dvdread_getbits(&state, 8);
  sa->lang_code = dvdread_getbits(&state, 16);
  sa->lang_extension = dvdread_getbits(&state, 8);
  sa->code_extension = dvdread_getbits(&state, 8);
}

static void read_user_ops(user_ops_t *uo) {
  getbits_state_t state;
  uint8_t buf[sizeof(user_ops_t)];

  memcpy(buf, uo, sizeof(user_ops_t));
  if (!dvdread_getbits_init(&state, buf)) abort();
  uo->zero                           = dvdread_getbits(&state, 7);
  uo->video_pres_mode_change         = dvdread_getbits(&state, 1);
  uo->karaoke_audio_pres_mode_change = dvdread_getbits(&state, 1);
  uo->angle_change                   = dvdread_getbits(&state, 1);
  uo->subpic_stream_change           = dvdread_getbits(&state, 1);
  uo->audio_stream_change            = dvdread_getbits(&state, 1);
  uo->pause_on                       = dvdread_getbits(&state, 1);
  uo->still_off                      = dvdread_getbits(&state, 1);
  uo->button_select_or_activate      = dvdread_getbits(&state, 1);
  uo->resume                         = dvdread_getbits(&state, 1);
  uo->chapter_menu_call              = dvdread_getbits(&state, 1);
  uo->angle_menu_call                = dvdread_getbits(&state, 1);
  uo->audio_menu_call                = dvdread_getbits(&state, 1);
  uo->subpic_menu_call               = dvdread_getbits(&state, 1);
  uo->root_menu_call                 = dvdread_getbits(&state, 1);
  uo->title_menu_call                = dvdread_getbits(&state, 1);
  uo->backward_scan                  = dvdread_getbits(&state, 1);
  uo->forward_scan                   = dvdread_getbits(&state, 1);
  uo->next_pg_search                 = dvdread_getbits(&state, 1);
  uo->prev_or_top_pg_search          = dvdread_getbits(&state, 1);
  uo->time_or_chapter_search         = dvdread_getbits(&state, 1);
  uo->go_up                          = dvdread_getbits(&state, 1);
  uo->stop                           = dvdread_getbits(&state, 1);
  uo->title_play                     = dvdread_getbits(&state, 1);
  uo->chapter_search_or_play         = dvdread_getbits(&state, 1);
  uo->title_or_time_play             = dvdread_getbits(&state, 1);
}

static void read_pgci_srp(pgci_srp_t *ps) {
  getbits_state_t state;
  uint8_t buf[sizeof(pgci_srp_t)];

  memcpy(buf, ps, sizeof(pgci_srp_t));
  if (!dvdread_getbits_init(&state, buf)) abort();
  ps->entry_id                       = dvdread_getbits(&state, 8);
  ps->block_mode                     = dvdread_getbits(&state, 2);
  ps->block_type                     = dvdread_getbits(&state, 2);
  ps->unknown1                       = dvdread_getbits(&state, 4);
  ps->ptl_id_mask                    = dvdread_getbits(&state, 16);
  ps->pgc_start_byte                 = dvdread_getbits(&state, 32);
}

static void read_cell_playback(cell_playback_t *cp) {
  getbits_state_t state;
  uint8_t buf[sizeof(cell_playback_t)];

  memcpy(buf, cp, sizeof(cell_playback_t));
  if (!dvdread_getbits_init(&state, buf)) abort();
  cp->block_mode                      = dvdread_getbits(&state, 2);
  cp->block_type                      = dvdread_getbits(&state, 2);
  cp->seamless_play                   = dvdread_getbits(&state, 1);
  cp->interleaved                     = dvdread_getbits(&state, 1);
  cp->stc_discontinuity               = dvdread_getbits(&state, 1);
  cp->seamless_angle                  = dvdread_getbits(&state, 1);
  cp->playback_mode                   = dvdread_getbits(&state, 1);
  cp->restricted                      = dvdread_getbits(&state, 1);
  cp->unknown2                        = dvdread_getbits(&state, 6);
  cp->still_time                      = dvdread_getbits(&state, 8);
  cp->cell_cmd_nr                     = dvdread_getbits(&state, 8);

  cp->playback_time.hour              = dvdread_getbits(&state, 8);
  cp->playback_time.minute            = dvdread_getbits(&state, 8);
  cp->playback_time.second            = dvdread_getbits(&state, 8);
  cp->playback_time.frame_u           = dvdread_getbits(&state, 8);

  cp->first_sector                    = dvdread_getbits(&state, 32);
  cp->first_ilvu_end_sector           = dvdread_getbits(&state, 32);
  cp->last_vobu_start_sector          = dvdread_getbits(&state, 32);
  cp->last_sector                     = dvdread_getbits(&state, 32);
}

static void read_playback_type(playback_type_t *pt) {
  getbits_state_t state;
  uint8_t buf[sizeof(playback_type_t)];

  memcpy(buf, pt, sizeof(playback_type_t));
  if (!dvdread_getbits_init(&state, buf)) abort();
  pt->zero_1                          = dvdread_getbits(&state, 1);
  pt->multi_or_random_pgc_title       = dvdread_getbits(&state, 1);
  pt->jlc_exists_in_cell_cmd          = dvdread_getbits(&state, 1);
  pt->jlc_exists_in_prepost_cmd       = dvdread_getbits(&state, 1);
  pt->jlc_exists_in_button_cmd        = dvdread_getbits(&state, 1);
  pt->jlc_exists_in_tt_dom            = dvdread_getbits(&state, 1);
  pt->chapter_search_or_play          = dvdread_getbits(&state, 1);
  pt->title_or_time_play              = dvdread_getbits(&state, 1);
}

static void free_ptl_mait(ptl_mait_t* ptl_mait, int num_entries) {
  int i;
  for (i = 0; i < num_entries; i++)
    free(ptl_mait->countries[i].pf_ptl_mai);

  free(ptl_mait->countries);
  free(ptl_mait);
}

ifo_handle_t *ifoOpen(dvd_reader_t *dvd, int title) {
  ifo_handle_t *ifofile;
  int bup_file_opened = 0;
  char ifo_filename[13];

  ifofile = (ifo_handle_t *)malloc(sizeof(ifo_handle_t));
  if(!ifofile)
    return NULL;

  memset(ifofile, 0, sizeof(ifo_handle_t));

  ifofile->file = DVDOpenFile(dvd, title, DVD_READ_INFO_FILE);
  if(!ifofile->file) { /* Failed to open IFO, try to open BUP */
    ifofile->file = DVDOpenFile(dvd, title, DVD_READ_INFO_BACKUP_FILE);
    bup_file_opened = 1;
  }

  if (title)
    snprintf(ifo_filename, 12, "VTS_%02d_0.%s", title, bup_file_opened ? "BUP" : "IFO");
  else
    snprintf(ifo_filename, 12, "VIDEO_TS.%s", bup_file_opened ? "BUP" : "IFO");

  ifo_filename[12] = '\0';

  if(!ifofile->file) {
    fprintf(stderr, "libdvdread: Can't open file %s.\n", ifo_filename);
    free(ifofile);
    return NULL;
  }

  /* First check if this is a VMGI file. */
  if(ifoRead_VMG(ifofile)) {

    /* These are both mandatory. */
    if(!ifoRead_FP_PGC(ifofile) || !ifoRead_TT_SRPT(ifofile))
      goto ifoOpen_try_bup;

    ifoRead_PGCI_UT(ifofile);
    ifoRead_PTL_MAIT(ifofile);

    /* This is also mandatory. */
    if(!ifoRead_VTS_ATRT(ifofile))
      goto ifoOpen_try_bup;

    ifoRead_TXTDT_MGI(ifofile);
    ifoRead_C_ADT(ifofile);
    ifoRead_VOBU_ADMAP(ifofile);

    return ifofile;
  }

  if(ifoRead_VTS(ifofile)) {

    if(!ifoRead_VTS_PTT_SRPT(ifofile) || !ifoRead_PGCIT(ifofile))
      goto ifoOpen_try_bup;

    ifoRead_PGCI_UT(ifofile);
    ifoRead_VTS_TMAPT(ifofile);
    ifoRead_C_ADT(ifofile);
    ifoRead_VOBU_ADMAP(ifofile);

    if(!ifoRead_TITLE_C_ADT(ifofile) || !ifoRead_TITLE_VOBU_ADMAP(ifofile))
      goto ifoOpen_try_bup;

    return ifofile;
  }

ifoOpen_try_bup:
  if (bup_file_opened)
    goto ifoOpen_fail;

  /* Try BUP instead */
  ifoClose(ifofile);

  ifofile = (ifo_handle_t *)malloc(sizeof(ifo_handle_t));
  if(!ifofile)
    return NULL;

  memset(ifofile, 0, sizeof(ifo_handle_t));
  ifofile->file = DVDOpenFile(dvd, title, DVD_READ_INFO_BACKUP_FILE);

  if (title)
    snprintf(ifo_filename, 12, "VTS_%02d_0.BUP", title);
  else
    strncpy(ifo_filename, "VIDEO_TS.BUP", 12);

  if (!ifofile->file) {
    fprintf(stderr, "libdvdread: Can't open file %s.\n", ifo_filename);
    free(ifofile);
    return NULL;
  }
  bup_file_opened = 1;

  /* First check if this is a VMGI file. */
  if(ifoRead_VMG(ifofile)) {

    /* These are both mandatory. */
    if(!ifoRead_FP_PGC(ifofile) || !ifoRead_TT_SRPT(ifofile))
      goto ifoOpen_fail;

    ifoRead_PGCI_UT(ifofile);
    ifoRead_PTL_MAIT(ifofile);

    /* This is also mandatory. */
    if(!ifoRead_VTS_ATRT(ifofile))
      goto ifoOpen_fail;

    ifoRead_TXTDT_MGI(ifofile);
    ifoRead_C_ADT(ifofile);
    ifoRead_VOBU_ADMAP(ifofile);

    return ifofile;
  }

  if(ifoRead_VTS(ifofile)) {

    if(!ifoRead_VTS_PTT_SRPT(ifofile) || !ifoRead_PGCIT(ifofile))
      goto ifoOpen_fail;

    ifoRead_PGCI_UT(ifofile);
    ifoRead_VTS_TMAPT(ifofile);
    ifoRead_C_ADT(ifofile);
    ifoRead_VOBU_ADMAP(ifofile);

    if(!ifoRead_TITLE_C_ADT(ifofile) || !ifoRead_TITLE_VOBU_ADMAP(ifofile))
      goto ifoOpen_fail;

    return ifofile;
  }

ifoOpen_fail:
  fprintf(stderr, "libdvdread: Invalid IFO for title %d (%s).\n", title, ifo_filename);
  ifoClose(ifofile);
  return NULL;
}


ifo_handle_t *ifoOpenVMGI(dvd_reader_t *dvd) {
  ifo_handle_t *ifofile;

  ifofile = (ifo_handle_t *)malloc(sizeof(ifo_handle_t));
  if(!ifofile)
    return NULL;

  memset(ifofile, 0, sizeof(ifo_handle_t));

  ifofile->file = DVDOpenFile(dvd, 0, DVD_READ_INFO_FILE);
  if(!ifofile->file) /* Should really catch any error and try to fallback */
    ifofile->file = DVDOpenFile(dvd, 0, DVD_READ_INFO_BACKUP_FILE);
  if(!ifofile->file) {
    fprintf(stderr, "libdvdread: Can't open file VIDEO_TS.IFO.\n");
    free(ifofile);
    return NULL;
  }

  if(ifoRead_VMG(ifofile))
    return ifofile;

  fprintf(stderr, "libdvdread,ifoOpenVMGI(): Invalid main menu IFO (VIDEO_TS.IFO).\n");
  ifoClose(ifofile);
  return NULL;
}


ifo_handle_t *ifoOpenVTSI(dvd_reader_t *dvd, int title) {
  ifo_handle_t *ifofile;

  ifofile = (ifo_handle_t *)malloc(sizeof(ifo_handle_t));
  if(!ifofile)
    return NULL;

  memset(ifofile, 0, sizeof(ifo_handle_t));

  if(title <= 0 || title > 99) {
    fprintf(stderr, "libdvdread: ifoOpenVTSI invalid title (%d).\n", title);
    free(ifofile);
    return NULL;
  }

  ifofile->file = DVDOpenFile(dvd, title, DVD_READ_INFO_FILE);
  if(!ifofile->file) /* Should really catch any error and try to fallback */
    ifofile->file = DVDOpenFile(dvd, title, DVD_READ_INFO_BACKUP_FILE);
  if(!ifofile->file) {
    fprintf(stderr, "libdvdread: Can't open file VTS_%02d_0.IFO.\n", title);
    free(ifofile);
    return NULL;
  }

  ifoRead_VTS(ifofile);
  if(ifofile->vtsi_mat)
    return ifofile;

  fprintf(stderr, "libdvdread: Invalid IFO for title %d (VTS_%02d_0.IFO).\n",
          title, title);
  ifoClose(ifofile);
  return NULL;
}


void ifoClose(ifo_handle_t *ifofile) {
  if(!ifofile)
    return;

  ifoFree_VOBU_ADMAP(ifofile);
  ifoFree_TITLE_VOBU_ADMAP(ifofile);
  ifoFree_C_ADT(ifofile);
  ifoFree_TITLE_C_ADT(ifofile);
  ifoFree_TXTDT_MGI(ifofile);
  ifoFree_VTS_ATRT(ifofile);
  ifoFree_PTL_MAIT(ifofile);
  ifoFree_PGCI_UT(ifofile);
  ifoFree_TT_SRPT(ifofile);
  ifoFree_FP_PGC(ifofile);
  ifoFree_PGCIT(ifofile);
  ifoFree_VTS_PTT_SRPT(ifofile);
  ifoFree_VTS_TMAPT(ifofile);

  if(ifofile->vmgi_mat)
    free(ifofile->vmgi_mat);

  if(ifofile->vtsi_mat)
    free(ifofile->vtsi_mat);

  DVDCloseFile(ifofile->file);
  ifofile->file = 0;
  free(ifofile);
  ifofile = 0;
}


static int ifoRead_VMG(ifo_handle_t *ifofile) {
  vmgi_mat_t *vmgi_mat;

  vmgi_mat = (vmgi_mat_t *)malloc(sizeof(vmgi_mat_t));
  if(!vmgi_mat)
    return 0;

  ifofile->vmgi_mat = vmgi_mat;

  if(!DVDFileSeek_(ifofile->file, 0)) {
    free(ifofile->vmgi_mat);
    ifofile->vmgi_mat = 0;
    return 0;
  }

  if(!DVDReadBytes(ifofile->file, vmgi_mat, sizeof(vmgi_mat_t))) {
    free(ifofile->vmgi_mat);
    ifofile->vmgi_mat = 0;
    return 0;
  }

  if(strncmp("DVDVIDEO-VMG", vmgi_mat->vmg_identifier, 12) != 0) {
    free(ifofile->vmgi_mat);
    ifofile->vmgi_mat = 0;
    return 0;
  }

  B2N_32(vmgi_mat->vmg_last_sector);
  B2N_32(vmgi_mat->vmgi_last_sector);
  B2N_32(vmgi_mat->vmg_category);
  B2N_16(vmgi_mat->vmg_nr_of_volumes);
  B2N_16(vmgi_mat->vmg_this_volume_nr);
  B2N_16(vmgi_mat->vmg_nr_of_title_sets);
  B2N_64(vmgi_mat->vmg_pos_code);
  B2N_32(vmgi_mat->vmgi_last_byte);
  B2N_32(vmgi_mat->first_play_pgc);
  B2N_32(vmgi_mat->vmgm_vobs);
  B2N_32(vmgi_mat->tt_srpt);
  B2N_32(vmgi_mat->vmgm_pgci_ut);
  B2N_32(vmgi_mat->ptl_mait);
  B2N_32(vmgi_mat->vts_atrt);
  B2N_32(vmgi_mat->txtdt_mgi);
  B2N_32(vmgi_mat->vmgm_c_adt);
  B2N_32(vmgi_mat->vmgm_vobu_admap);
  read_video_attr(&vmgi_mat->vmgm_video_attr);
  read_audio_attr(&vmgi_mat->vmgm_audio_attr);
  read_subp_attr(&vmgi_mat->vmgm_subp_attr);


  CHECK_ZERO(vmgi_mat->zero_1);
  CHECK_ZERO(vmgi_mat->zero_2);
  CHECK_ZERO(vmgi_mat->zero_3);
  CHECK_ZERO(vmgi_mat->zero_4);
  CHECK_ZERO(vmgi_mat->zero_5);
  CHECK_ZERO(vmgi_mat->zero_6);
  CHECK_ZERO(vmgi_mat->zero_7);
  CHECK_ZERO(vmgi_mat->zero_8);
  CHECK_ZERO(vmgi_mat->zero_9);
  CHECK_ZERO(vmgi_mat->zero_10);
  CHECK_VALUE(vmgi_mat->vmg_last_sector != 0);
  CHECK_VALUE(vmgi_mat->vmgi_last_sector != 0);
  CHECK_VALUE(vmgi_mat->vmgi_last_sector * 2 <= vmgi_mat->vmg_last_sector);
  CHECK_VALUE(vmgi_mat->vmgi_last_sector * 2 <= vmgi_mat->vmg_last_sector);
  CHECK_VALUE(vmgi_mat->vmg_nr_of_volumes != 0);
  CHECK_VALUE(vmgi_mat->vmg_this_volume_nr != 0);
  CHECK_VALUE(vmgi_mat->vmg_this_volume_nr <= vmgi_mat->vmg_nr_of_volumes);
  CHECK_VALUE(vmgi_mat->disc_side == 1 || vmgi_mat->disc_side == 2);
  CHECK_VALUE(vmgi_mat->vmg_nr_of_title_sets != 0);
  CHECK_VALUE(vmgi_mat->vmgi_last_byte >= 341);
  CHECK_VALUE(vmgi_mat->vmgi_last_byte / DVD_BLOCK_LEN <=
              vmgi_mat->vmgi_last_sector);
  /* It seems that first_play_pgc is optional. */
  CHECK_VALUE(vmgi_mat->first_play_pgc < vmgi_mat->vmgi_last_byte);
  CHECK_VALUE(vmgi_mat->vmgm_vobs == 0 ||
              (vmgi_mat->vmgm_vobs > vmgi_mat->vmgi_last_sector &&
               vmgi_mat->vmgm_vobs < vmgi_mat->vmg_last_sector));
  CHECK_VALUE(vmgi_mat->tt_srpt <= vmgi_mat->vmgi_last_sector);
  CHECK_VALUE(vmgi_mat->vmgm_pgci_ut <= vmgi_mat->vmgi_last_sector);
  CHECK_VALUE(vmgi_mat->ptl_mait <= vmgi_mat->vmgi_last_sector);
  CHECK_VALUE(vmgi_mat->vts_atrt <= vmgi_mat->vmgi_last_sector);
  CHECK_VALUE(vmgi_mat->txtdt_mgi <= vmgi_mat->vmgi_last_sector);
  CHECK_VALUE(vmgi_mat->vmgm_c_adt <= vmgi_mat->vmgi_last_sector);
  CHECK_VALUE(vmgi_mat->vmgm_vobu_admap <= vmgi_mat->vmgi_last_sector);

  CHECK_VALUE(vmgi_mat->nr_of_vmgm_audio_streams <= 1);
  CHECK_VALUE(vmgi_mat->nr_of_vmgm_subp_streams <= 1);

  return 1;
}


static int ifoRead_VTS(ifo_handle_t *ifofile) {
  vtsi_mat_t *vtsi_mat;
  int i;

  vtsi_mat = (vtsi_mat_t *)malloc(sizeof(vtsi_mat_t));
  if(!vtsi_mat)
    return 0;

  ifofile->vtsi_mat = vtsi_mat;

  if(!DVDFileSeek_(ifofile->file, 0)) {
    free(ifofile->vtsi_mat);
    ifofile->vtsi_mat = 0;
    return 0;
  }

  if(!(DVDReadBytes(ifofile->file, vtsi_mat, sizeof(vtsi_mat_t)))) {
    free(ifofile->vtsi_mat);
    ifofile->vtsi_mat = 0;
    return 0;
  }

  if(strncmp("DVDVIDEO-VTS", vtsi_mat->vts_identifier, 12) != 0) {
    free(ifofile->vtsi_mat);
    ifofile->vtsi_mat = 0;
    return 0;
  }

  read_video_attr(&vtsi_mat->vtsm_video_attr);
  read_video_attr(&vtsi_mat->vts_video_attr);
  read_audio_attr(&vtsi_mat->vtsm_audio_attr);
  for(i=0; i<8; i++)
    read_audio_attr(&vtsi_mat->vts_audio_attr[i]);
  read_subp_attr(&vtsi_mat->vtsm_subp_attr);
  for(i=0; i<32; i++)
    read_subp_attr(&vtsi_mat->vts_subp_attr[i]);
  B2N_32(vtsi_mat->vts_last_sector);
  B2N_32(vtsi_mat->vtsi_last_sector);
  B2N_32(vtsi_mat->vts_category);
  B2N_32(vtsi_mat->vtsi_last_byte);
  B2N_32(vtsi_mat->vtsm_vobs);
  B2N_32(vtsi_mat->vtstt_vobs);
  B2N_32(vtsi_mat->vts_ptt_srpt);
  B2N_32(vtsi_mat->vts_pgcit);
  B2N_32(vtsi_mat->vtsm_pgci_ut);
  B2N_32(vtsi_mat->vts_tmapt);
  B2N_32(vtsi_mat->vtsm_c_adt);
  B2N_32(vtsi_mat->vtsm_vobu_admap);
  B2N_32(vtsi_mat->vts_c_adt);
  B2N_32(vtsi_mat->vts_vobu_admap);


  CHECK_ZERO(vtsi_mat->zero_1);
  CHECK_ZERO(vtsi_mat->zero_2);
  CHECK_ZERO(vtsi_mat->zero_3);
  CHECK_ZERO(vtsi_mat->zero_4);
  CHECK_ZERO(vtsi_mat->zero_5);
  CHECK_ZERO(vtsi_mat->zero_6);
  CHECK_ZERO(vtsi_mat->zero_7);
  CHECK_ZERO(vtsi_mat->zero_8);
  CHECK_ZERO(vtsi_mat->zero_9);
  CHECK_ZERO(vtsi_mat->zero_10);
  CHECK_ZERO(vtsi_mat->zero_11);
  CHECK_ZERO(vtsi_mat->zero_12);
  CHECK_ZERO(vtsi_mat->zero_13);
  CHECK_ZERO(vtsi_mat->zero_14);
  CHECK_ZERO(vtsi_mat->zero_15);
  CHECK_ZERO(vtsi_mat->zero_16);
  CHECK_ZERO(vtsi_mat->zero_17);
  CHECK_ZERO(vtsi_mat->zero_18);
  CHECK_ZERO(vtsi_mat->zero_19);
  CHECK_ZERO(vtsi_mat->zero_20);
  CHECK_ZERO(vtsi_mat->zero_21);
  CHECK_VALUE(vtsi_mat->vtsi_last_sector*2 <= vtsi_mat->vts_last_sector);
  CHECK_VALUE(vtsi_mat->vtsi_last_byte/DVD_BLOCK_LEN <= vtsi_mat->vtsi_last_sector);
  CHECK_VALUE(vtsi_mat->vtsm_vobs == 0 ||
              (vtsi_mat->vtsm_vobs > vtsi_mat->vtsi_last_sector &&
               vtsi_mat->vtsm_vobs < vtsi_mat->vts_last_sector));
  CHECK_VALUE(vtsi_mat->vtstt_vobs == 0 ||
              (vtsi_mat->vtstt_vobs > vtsi_mat->vtsi_last_sector &&
               vtsi_mat->vtstt_vobs < vtsi_mat->vts_last_sector));
  CHECK_VALUE(vtsi_mat->vts_ptt_srpt <= vtsi_mat->vtsi_last_sector);
  CHECK_VALUE(vtsi_mat->vts_pgcit <= vtsi_mat->vtsi_last_sector);
  CHECK_VALUE(vtsi_mat->vtsm_pgci_ut <= vtsi_mat->vtsi_last_sector);
  CHECK_VALUE(vtsi_mat->vts_tmapt <= vtsi_mat->vtsi_last_sector);
  CHECK_VALUE(vtsi_mat->vtsm_c_adt <= vtsi_mat->vtsi_last_sector);
  CHECK_VALUE(vtsi_mat->vtsm_vobu_admap <= vtsi_mat->vtsi_last_sector);
  CHECK_VALUE(vtsi_mat->vts_c_adt <= vtsi_mat->vtsi_last_sector);
  CHECK_VALUE(vtsi_mat->vts_vobu_admap <= vtsi_mat->vtsi_last_sector);

  CHECK_VALUE(vtsi_mat->nr_of_vtsm_audio_streams <= 1);
  CHECK_VALUE(vtsi_mat->nr_of_vtsm_subp_streams <= 1);

  CHECK_VALUE(vtsi_mat->nr_of_vts_audio_streams <= 8);
  for(i = vtsi_mat->nr_of_vts_audio_streams; i < 8; i++)
    CHECK_ZERO(vtsi_mat->vts_audio_attr[i]);

  CHECK_VALUE(vtsi_mat->nr_of_vts_subp_streams <= 32);
  for(i = vtsi_mat->nr_of_vts_subp_streams; i < 32; i++)
    CHECK_ZERO(vtsi_mat->vts_subp_attr[i]);

  for(i = 0; i < 8; i++) {
    read_multichannel_ext(&vtsi_mat->vts_mu_audio_attr[i]);
    CHECK_ZERO0(vtsi_mat->vts_mu_audio_attr[i].zero1);
    CHECK_ZERO0(vtsi_mat->vts_mu_audio_attr[i].zero2);
    CHECK_ZERO0(vtsi_mat->vts_mu_audio_attr[i].zero3);
    CHECK_ZERO0(vtsi_mat->vts_mu_audio_attr[i].zero4);
    CHECK_ZERO0(vtsi_mat->vts_mu_audio_attr[i].zero5);
    CHECK_ZERO(vtsi_mat->vts_mu_audio_attr[i].zero6);
  }

  return 1;
}


static int ifoRead_PGC_COMMAND_TBL(ifo_handle_t *ifofile,
                                   pgc_command_tbl_t *cmd_tbl,
                                   unsigned int offset) {

  memset(cmd_tbl, 0, sizeof(pgc_command_tbl_t));

  if(!DVDFileSeek_(ifofile->file, offset))
    return 0;

  if(!(DVDReadBytes(ifofile->file, cmd_tbl, PGC_COMMAND_TBL_SIZE)))
    return 0;

  B2N_16(cmd_tbl->nr_of_pre);
  B2N_16(cmd_tbl->nr_of_post);
  B2N_16(cmd_tbl->nr_of_cell);

  CHECK_VALUE(cmd_tbl->nr_of_pre + cmd_tbl->nr_of_post + cmd_tbl->nr_of_cell<= 255);

  if(cmd_tbl->nr_of_pre != 0) {
    unsigned int pre_cmds_size  = cmd_tbl->nr_of_pre * COMMAND_DATA_SIZE;
    cmd_tbl->pre_cmds = (vm_cmd_t *)malloc(pre_cmds_size);
    if(!cmd_tbl->pre_cmds)
      return 0;

    if(!(DVDReadBytes(ifofile->file, cmd_tbl->pre_cmds, pre_cmds_size))) {
      free(cmd_tbl->pre_cmds);
      return 0;
    }
  }

  if(cmd_tbl->nr_of_post != 0) {
    unsigned int post_cmds_size = cmd_tbl->nr_of_post * COMMAND_DATA_SIZE;
    cmd_tbl->post_cmds = (vm_cmd_t *)malloc(post_cmds_size);
    if(!cmd_tbl->post_cmds) {
      if(cmd_tbl->pre_cmds)
        free(cmd_tbl->pre_cmds);
      return 0;
    }
    if(!(DVDReadBytes(ifofile->file, cmd_tbl->post_cmds, post_cmds_size))) {
      if(cmd_tbl->pre_cmds)
        free(cmd_tbl->pre_cmds);
      free(cmd_tbl->post_cmds);
      return 0;
    }
  }

  if(cmd_tbl->nr_of_cell != 0) {
    unsigned int cell_cmds_size = cmd_tbl->nr_of_cell * COMMAND_DATA_SIZE;
    cmd_tbl->cell_cmds = (vm_cmd_t *)malloc(cell_cmds_size);
    if(!cmd_tbl->cell_cmds) {
      if(cmd_tbl->pre_cmds)
        free(cmd_tbl->pre_cmds);
      if(cmd_tbl->post_cmds)
        free(cmd_tbl->post_cmds);
      return 0;
    }
    if(!(DVDReadBytes(ifofile->file, cmd_tbl->cell_cmds, cell_cmds_size))) {
      if(cmd_tbl->pre_cmds)
        free(cmd_tbl->pre_cmds);
      if(cmd_tbl->post_cmds)
        free(cmd_tbl->post_cmds);
      free(cmd_tbl->cell_cmds);
      return 0;
    }
  }

  /*
   * Make a run over all the commands and see that we can interpret them all?
   */
  return 1;
}


static void ifoFree_PGC_COMMAND_TBL(pgc_command_tbl_t *cmd_tbl) {
  if(cmd_tbl) {
    if(cmd_tbl->nr_of_pre && cmd_tbl->pre_cmds)
      free(cmd_tbl->pre_cmds);
    if(cmd_tbl->nr_of_post && cmd_tbl->post_cmds)
      free(cmd_tbl->post_cmds);
    if(cmd_tbl->nr_of_cell && cmd_tbl->cell_cmds)
      free(cmd_tbl->cell_cmds);
    free(cmd_tbl);
  }
}

static int ifoRead_PGC_PROGRAM_MAP(ifo_handle_t *ifofile,
                                   pgc_program_map_t *program_map,
                                   unsigned int nr, unsigned int offset) {
  unsigned int size = nr * sizeof(pgc_program_map_t);

  if(!DVDFileSeek_(ifofile->file, offset))
    return 0;

  if(!(DVDReadBytes(ifofile->file, program_map, size)))
    return 0;

  return 1;
}

static int ifoRead_CELL_PLAYBACK_TBL(ifo_handle_t *ifofile,
                                     cell_playback_t *cell_playback,
                                     unsigned int nr, unsigned int offset) {
  unsigned int i;
  unsigned int size = nr * sizeof(cell_playback_t);

  if(!DVDFileSeek_(ifofile->file, offset))
    return 0;

  if(!(DVDReadBytes(ifofile->file, cell_playback, size)))
    return 0;

  for(i = 0; i < nr; i++) {
    read_cell_playback(&cell_playback[i]);
    /* Changed < to <= because this was false in the movie 'Pi'. */
    CHECK_VALUE(cell_playback[i].last_vobu_start_sector <=
                cell_playback[i].last_sector);
    CHECK_VALUE(cell_playback[i].first_sector <=
                cell_playback[i].last_vobu_start_sector);
  }

  return 1;
}


static int ifoRead_CELL_POSITION_TBL(ifo_handle_t *ifofile,
                                     cell_position_t *cell_position,
                                     unsigned int nr, unsigned int offset) {
  unsigned int i;
  unsigned int size = nr * sizeof(cell_position_t);

  if(!DVDFileSeek_(ifofile->file, offset))
    return 0;

  if(!(DVDReadBytes(ifofile->file, cell_position, size)))
    return 0;

  for(i = 0; i < nr; i++) {
    B2N_16(cell_position[i].vob_id_nr);
    CHECK_ZERO(cell_position[i].zero_1);
  }

  return 1;
}

static int ifoRead_PGC(ifo_handle_t *ifofile, pgc_t *pgc, unsigned int offset) {
  unsigned int i;

  if(!DVDFileSeek_(ifofile->file, offset))
    return 0;

  if(!(DVDReadBytes(ifofile->file, pgc, PGC_SIZE)))
    return 0;

  read_user_ops(&pgc->prohibited_ops);
  B2N_16(pgc->next_pgc_nr);
  B2N_16(pgc->prev_pgc_nr);
  B2N_16(pgc->goup_pgc_nr);
  B2N_16(pgc->command_tbl_offset);
  B2N_16(pgc->program_map_offset);
  B2N_16(pgc->cell_playback_offset);
  B2N_16(pgc->cell_position_offset);

  for(i = 0; i < 8; i++)
    B2N_16(pgc->audio_control[i]);
  for(i = 0; i < 32; i++)
    B2N_32(pgc->subp_control[i]);
  for(i = 0; i < 16; i++)
    B2N_32(pgc->palette[i]);

  CHECK_ZERO(pgc->zero_1);
  CHECK_VALUE(pgc->nr_of_programs <= pgc->nr_of_cells);

  /* verify time (look at print_time) */
  for(i = 0; i < 8; i++)
    if(!(pgc->audio_control[i] & 0x8000)) /* The 'is present' bit */
      CHECK_ZERO(pgc->audio_control[i]);
  for(i = 0; i < 32; i++)
    if(!(pgc->subp_control[i] & 0x80000000)) /* The 'is present' bit */
      CHECK_ZERO(pgc->subp_control[i]);

  /* Check that time is 0:0:0:0 also if nr_of_programs == 0 */
  if(pgc->nr_of_programs == 0) {
    CHECK_ZERO(pgc->still_time);
    CHECK_ZERO(pgc->pg_playback_mode); /* ?? */
    CHECK_VALUE(pgc->program_map_offset == 0);
    CHECK_VALUE(pgc->cell_playback_offset == 0);
    CHECK_VALUE(pgc->cell_position_offset == 0);
  } else {
    CHECK_VALUE(pgc->program_map_offset != 0);
    CHECK_VALUE(pgc->cell_playback_offset != 0);
    CHECK_VALUE(pgc->cell_position_offset != 0);
  }

  if(pgc->command_tbl_offset != 0) {
    pgc->command_tbl = malloc(sizeof(pgc_command_tbl_t));
    if(!pgc->command_tbl)
      return 0;

    if(!ifoRead_PGC_COMMAND_TBL(ifofile, pgc->command_tbl,
                                offset + pgc->command_tbl_offset)) {
      free(pgc->command_tbl);
      return 0;
    }
  } else {
    pgc->command_tbl = NULL;
  }

  if(pgc->program_map_offset != 0 && pgc->nr_of_programs>0) {
    pgc->program_map = malloc(pgc->nr_of_programs * sizeof(pgc_program_map_t));
    if(!pgc->program_map) {
      ifoFree_PGC_COMMAND_TBL(pgc->command_tbl);
      return 0;
    }
    if(!ifoRead_PGC_PROGRAM_MAP(ifofile, pgc->program_map,pgc->nr_of_programs,
                                offset + pgc->program_map_offset)) {
      ifoFree_PGC_COMMAND_TBL(pgc->command_tbl);
      free(pgc->program_map);
      return 0;
    }
  } else {
    pgc->program_map = NULL;
  }

  if(pgc->cell_playback_offset != 0 && pgc->nr_of_cells>0) {
    pgc->cell_playback = malloc(pgc->nr_of_cells * sizeof(cell_playback_t));
    if(!pgc->cell_playback) {
      ifoFree_PGC_COMMAND_TBL(pgc->command_tbl);
      if(pgc->program_map)
        free(pgc->program_map);
      return 0;
    }
    if(!ifoRead_CELL_PLAYBACK_TBL(ifofile, pgc->cell_playback,
                                  pgc->nr_of_cells,
                                  offset + pgc->cell_playback_offset)) {
      ifoFree_PGC_COMMAND_TBL(pgc->command_tbl);
      if(pgc->program_map)
        free(pgc->program_map);
      free(pgc->cell_playback);
      return 0;
    }
  } else {
    pgc->cell_playback = NULL;
  }

  if(pgc->cell_position_offset != 0 && pgc->nr_of_cells>0) {
    pgc->cell_position = malloc(pgc->nr_of_cells * sizeof(cell_position_t));
    if(!pgc->cell_position) {
      ifoFree_PGC(pgc);
      return 0;
    }
    if(!ifoRead_CELL_POSITION_TBL(ifofile, pgc->cell_position,
                                  pgc->nr_of_cells,
                                  offset + pgc->cell_position_offset)) {
      ifoFree_PGC(pgc);
      return 0;
    }
  } else {
    pgc->cell_position = NULL;
  }

  return 1;
}

int ifoRead_FP_PGC(ifo_handle_t *ifofile) {

  if(!ifofile)
    return 0;

  if(!ifofile->vmgi_mat)
    return 0;

  /* It seems that first_play_pgc is optional after all. */
  ifofile->first_play_pgc = 0;
  if(ifofile->vmgi_mat->first_play_pgc == 0)
    return 1;

  ifofile->first_play_pgc = (pgc_t *)malloc(sizeof(pgc_t));
  if(!ifofile->first_play_pgc)
    return 0;

  if(!ifoRead_PGC(ifofile, ifofile->first_play_pgc,
                  ifofile->vmgi_mat->first_play_pgc)) {
    free(ifofile->first_play_pgc);
    ifofile->first_play_pgc = 0;
    return 0;
  }

  return 1;
}

static void ifoFree_PGC(pgc_t *pgc) {
  if(pgc) {
    ifoFree_PGC_COMMAND_TBL(pgc->command_tbl);
    if(pgc->program_map)
      free(pgc->program_map);
    if(pgc->cell_playback)
      free(pgc->cell_playback);
    if(pgc->cell_position)
      free(pgc->cell_position);
  }
}

void ifoFree_FP_PGC(ifo_handle_t *ifofile) {
  if(!ifofile)
    return;

  if(ifofile->first_play_pgc) {
    ifoFree_PGC(ifofile->first_play_pgc);
    free(ifofile->first_play_pgc);
    ifofile->first_play_pgc = 0;
  }
}


int ifoRead_TT_SRPT(ifo_handle_t *ifofile) {
  tt_srpt_t *tt_srpt;
  int i, info_length;

  if(!ifofile)
    return 0;

  if(!ifofile->vmgi_mat)
    return 0;

  if(ifofile->vmgi_mat->tt_srpt == 0) /* mandatory */
    return 0;

  if(!DVDFileSeek_(ifofile->file, ifofile->vmgi_mat->tt_srpt * DVD_BLOCK_LEN))
    return 0;

  tt_srpt = (tt_srpt_t *)malloc(sizeof(tt_srpt_t));
  if(!tt_srpt)
    return 0;

  ifofile->tt_srpt = tt_srpt;

  if(!(DVDReadBytes(ifofile->file, tt_srpt, TT_SRPT_SIZE))) {
    fprintf(stderr, "libdvdread: Unable to read read TT_SRPT.\n");
    free(tt_srpt);
    return 0;
  }

  B2N_16(tt_srpt->nr_of_srpts);
  B2N_32(tt_srpt->last_byte);

  info_length = tt_srpt->last_byte + 1 - TT_SRPT_SIZE;

  tt_srpt->title = (title_info_t *)malloc(info_length);
  if(!tt_srpt->title) {
    free(tt_srpt);
    ifofile->tt_srpt = 0;
    return 0;
  }
  if(!(DVDReadBytes(ifofile->file, tt_srpt->title, info_length))) {
    fprintf(stderr, "libdvdread: Unable to read read TT_SRPT.\n");
    ifoFree_TT_SRPT(ifofile);
    return 0;
  }

  for(i =  0; i < tt_srpt->nr_of_srpts; i++) {
    B2N_16(tt_srpt->title[i].nr_of_ptts);
    B2N_16(tt_srpt->title[i].parental_id);
    B2N_32(tt_srpt->title[i].title_set_sector);
  }


  CHECK_ZERO(tt_srpt->zero_1);
  CHECK_VALUE(tt_srpt->nr_of_srpts != 0);
  CHECK_VALUE(tt_srpt->nr_of_srpts < 100); /* ?? */
  CHECK_VALUE((int)tt_srpt->nr_of_srpts * sizeof(title_info_t) <= info_length);

  for(i = 0; i < tt_srpt->nr_of_srpts; i++) {
    read_playback_type(&tt_srpt->title[i].pb_ty);
    CHECK_VALUE(tt_srpt->title[i].pb_ty.zero_1 == 0);
    CHECK_VALUE(tt_srpt->title[i].nr_of_angles != 0);
    CHECK_VALUE(tt_srpt->title[i].nr_of_angles < 10);
    /* CHECK_VALUE(tt_srpt->title[i].nr_of_ptts != 0); */
    /* XXX: this assertion breaks Ghostbusters: */
    CHECK_VALUE(tt_srpt->title[i].nr_of_ptts < 1000); /* ?? */
    CHECK_VALUE(tt_srpt->title[i].title_set_nr != 0);
    CHECK_VALUE(tt_srpt->title[i].title_set_nr < 100); /* ?? */
    CHECK_VALUE(tt_srpt->title[i].vts_ttn != 0);
    CHECK_VALUE(tt_srpt->title[i].vts_ttn < 100); /* ?? */
    /* CHECK_VALUE(tt_srpt->title[i].title_set_sector != 0); */
  }

  /* Make this a function */
#if 0
  if(memcmp((uint8_t *)tt_srpt->title +
            tt_srpt->nr_of_srpts * sizeof(title_info_t),
            my_friendly_zeros,
            info_length - tt_srpt->nr_of_srpts * sizeof(title_info_t))) {
    fprintf(stderr, "VMG_PTT_SRPT slack is != 0, ");
    hexdump((uint8_t *)tt_srpt->title +
            tt_srpt->nr_of_srpts * sizeof(title_info_t),
            info_length - tt_srpt->nr_of_srpts * sizeof(title_info_t));
  }
#endif

  return 1;
}


void ifoFree_TT_SRPT(ifo_handle_t *ifofile) {
  if(!ifofile)
    return;

  if(ifofile->tt_srpt) {
    free(ifofile->tt_srpt->title);
    free(ifofile->tt_srpt);
    ifofile->tt_srpt = 0;
  }
}


int ifoRead_VTS_PTT_SRPT(ifo_handle_t *ifofile) {
  vts_ptt_srpt_t *vts_ptt_srpt;
  int info_length, i, j;
  uint32_t *data;

  if(!ifofile)
    return 0;

  if(!ifofile->vtsi_mat)
    return 0;

  if(ifofile->vtsi_mat->vts_ptt_srpt == 0) /* mandatory */
    return 0;

  if(!DVDFileSeek_(ifofile->file,
                   ifofile->vtsi_mat->vts_ptt_srpt * DVD_BLOCK_LEN))
    return 0;

  vts_ptt_srpt = (vts_ptt_srpt_t *)malloc(sizeof(vts_ptt_srpt_t));
  if(!vts_ptt_srpt)
    return 0;

  ifofile->vts_ptt_srpt = vts_ptt_srpt;

  if(!(DVDReadBytes(ifofile->file, vts_ptt_srpt, VTS_PTT_SRPT_SIZE))) {
    fprintf(stderr, "libdvdread: Unable to read PTT search table.\n");
    free(vts_ptt_srpt);
    return 0;
  }

  B2N_16(vts_ptt_srpt->nr_of_srpts);
  B2N_32(vts_ptt_srpt->last_byte);

  CHECK_ZERO(vts_ptt_srpt->zero_1);
  CHECK_VALUE(vts_ptt_srpt->nr_of_srpts != 0);
  CHECK_VALUE(vts_ptt_srpt->nr_of_srpts < 100); /* ?? */

  info_length = vts_ptt_srpt->last_byte + 1 - VTS_PTT_SRPT_SIZE;

  data = (uint32_t *)malloc(info_length);
  if(!data) {
    free(vts_ptt_srpt);
    ifofile->vts_ptt_srpt = 0;
    return 0;
  }
  if(!(DVDReadBytes(ifofile->file, data, info_length))) {
    fprintf(stderr, "libdvdread: Unable to read PTT search table.\n");
    free(vts_ptt_srpt);
    free(data);
    ifofile->vts_ptt_srpt = 0;
    return 0;
  }

  for(i = 0; i < vts_ptt_srpt->nr_of_srpts; i++) {
    B2N_32(data[i]);
    /* assert(data[i] + sizeof(ptt_info_t) <= vts_ptt_srpt->last_byte + 1);
       Magic Knight Rayearth Daybreak is mastered very strange and has
       Titles with 0 PTTs. They all have a data[i] offsets beyond the end of
       of the vts_ptt_srpt structure. */
    CHECK_VALUE(data[i] + sizeof(ptt_info_t) <= vts_ptt_srpt->last_byte + 1 + 4);
  }

  vts_ptt_srpt->ttu_offset = data;

  vts_ptt_srpt->title = malloc(vts_ptt_srpt->nr_of_srpts * sizeof(ttu_t));
  if(!vts_ptt_srpt->title) {
    free(vts_ptt_srpt);
    free(data);
    ifofile->vts_ptt_srpt = 0;
    return 0;
  }
  for(i = 0; i < vts_ptt_srpt->nr_of_srpts; i++) {
    int n;
    if(i < vts_ptt_srpt->nr_of_srpts - 1)
      n = (data[i+1] - data[i]);
    else
      n = (vts_ptt_srpt->last_byte + 1 - data[i]);
    /* assert(n > 0 && (n % 4) == 0);
       Magic Knight Rayearth Daybreak is mastered very strange and has
       Titles with 0 PTTs. */
    if(n < 0) n = 0;
    CHECK_VALUE(n % 4 == 0);

    vts_ptt_srpt->title[i].nr_of_ptts = n / 4;
    vts_ptt_srpt->title[i].ptt = malloc(n * sizeof(ptt_info_t));
    if(!vts_ptt_srpt->title[i].ptt) {
      for(n = 0; n < i; n++)
        free(vts_ptt_srpt->title[n].ptt);
      free(vts_ptt_srpt);
      free(data);
      ifofile->vts_ptt_srpt = 0;
      return 0;
    }
    for(j = 0; j < vts_ptt_srpt->title[i].nr_of_ptts; j++) {
      /* The assert placed here because of Magic Knight Rayearth Daybreak */
      CHECK_VALUE(data[i] + sizeof(ptt_info_t) <= vts_ptt_srpt->last_byte + 1);
      vts_ptt_srpt->title[i].ptt[j].pgcn
        = *(uint16_t*)(((char *)data) + data[i] + 4*j - VTS_PTT_SRPT_SIZE);
      vts_ptt_srpt->title[i].ptt[j].pgn
        = *(uint16_t*)(((char *)data) + data[i] + 4*j + 2 - VTS_PTT_SRPT_SIZE);
    }
  }

  for(i = 0; i < vts_ptt_srpt->nr_of_srpts; i++) {
    for(j = 0; j < vts_ptt_srpt->title[i].nr_of_ptts; j++) {
      B2N_16(vts_ptt_srpt->title[i].ptt[j].pgcn);
      B2N_16(vts_ptt_srpt->title[i].ptt[j].pgn);
    }
  }

  for(i = 0; i < vts_ptt_srpt->nr_of_srpts; i++) {
    CHECK_VALUE(vts_ptt_srpt->title[i].nr_of_ptts < 1000); /* ?? */
    for(j = 0; j < vts_ptt_srpt->title[i].nr_of_ptts; j++) {
      CHECK_VALUE(vts_ptt_srpt->title[i].ptt[j].pgcn != 0 );
      CHECK_VALUE(vts_ptt_srpt->title[i].ptt[j].pgcn < 1000); /* ?? */
      CHECK_VALUE(vts_ptt_srpt->title[i].ptt[j].pgn != 0);
      CHECK_VALUE(vts_ptt_srpt->title[i].ptt[j].pgn < 100); /* ?? */
    }
  }

  return 1;
}


void ifoFree_VTS_PTT_SRPT(ifo_handle_t *ifofile) {
  if(!ifofile)
    return;

  if(ifofile->vts_ptt_srpt) {
    int i;
    for(i = 0; i < ifofile->vts_ptt_srpt->nr_of_srpts; i++)
      free(ifofile->vts_ptt_srpt->title[i].ptt);
    free(ifofile->vts_ptt_srpt->ttu_offset);
    free(ifofile->vts_ptt_srpt->title);
    free(ifofile->vts_ptt_srpt);
    ifofile->vts_ptt_srpt = 0;
  }
}


int ifoRead_PTL_MAIT(ifo_handle_t *ifofile) {
  ptl_mait_t *ptl_mait;
  int info_length;
  unsigned int i, j;

  if(!ifofile)
    return 0;

  if(!ifofile->vmgi_mat)
    return 0;

  if(ifofile->vmgi_mat->ptl_mait == 0)
    return 1;

  if(!DVDFileSeek_(ifofile->file, ifofile->vmgi_mat->ptl_mait * DVD_BLOCK_LEN))
    return 0;

  ptl_mait = (ptl_mait_t *)malloc(sizeof(ptl_mait_t));
  if(!ptl_mait)
    return 0;

  ifofile->ptl_mait = ptl_mait;

  if(!(DVDReadBytes(ifofile->file, ptl_mait, PTL_MAIT_SIZE))) {
    free(ptl_mait);
    ifofile->ptl_mait = 0;
    return 0;
  }

  B2N_16(ptl_mait->nr_of_countries);
  B2N_16(ptl_mait->nr_of_vtss);
  B2N_32(ptl_mait->last_byte);

  CHECK_VALUE(ptl_mait->nr_of_countries != 0);
  CHECK_VALUE(ptl_mait->nr_of_countries < 100); /* ?? */
  CHECK_VALUE(ptl_mait->nr_of_vtss != 0);
  CHECK_VALUE(ptl_mait->nr_of_vtss < 100); /* ?? */
  CHECK_VALUE(ptl_mait->nr_of_countries * PTL_MAIT_COUNTRY_SIZE
              <= ptl_mait->last_byte + 1 - PTL_MAIT_SIZE);

  info_length = ptl_mait->nr_of_countries * sizeof(ptl_mait_country_t);
  ptl_mait->countries = (ptl_mait_country_t *)malloc(info_length);
  if(!ptl_mait->countries) {
    free(ptl_mait);
    ifofile->ptl_mait = 0;
    return 0;
  }
  for(i = 0; i < ptl_mait->nr_of_countries; i++) {
    ptl_mait->countries[i].pf_ptl_mai = NULL;
  }

  for(i = 0; i < ptl_mait->nr_of_countries; i++) {
    if(!(DVDReadBytes(ifofile->file, &ptl_mait->countries[i], PTL_MAIT_COUNTRY_SIZE))) {
      fprintf(stderr, "libdvdread: Unable to read PTL_MAIT.\n");
      free(ptl_mait->countries);
      free(ptl_mait);
      ifofile->ptl_mait = 0;
      return 0;
    }
  }

  for(i = 0; i < ptl_mait->nr_of_countries; i++) {
    B2N_16(ptl_mait->countries[i].country_code);
    B2N_16(ptl_mait->countries[i].pf_ptl_mai_start_byte);
  }

  for(i = 0; i < ptl_mait->nr_of_countries; i++) {
    CHECK_ZERO(ptl_mait->countries[i].zero_1);
    CHECK_ZERO(ptl_mait->countries[i].zero_2);
    CHECK_VALUE(ptl_mait->countries[i].pf_ptl_mai_start_byte
                + sizeof(pf_level_t) * (ptl_mait->nr_of_vtss + 1) <= ptl_mait->last_byte + 1);
  }

  for(i = 0; i < ptl_mait->nr_of_countries; i++) {
    uint16_t *pf_temp;

    if(!DVDFileSeek_(ifofile->file,
                     ifofile->vmgi_mat->ptl_mait * DVD_BLOCK_LEN
                     + ptl_mait->countries[i].pf_ptl_mai_start_byte)) {
      fprintf(stderr, "libdvdread: Unable to seek PTL_MAIT table at index %d.\n",i);
      free(ptl_mait->countries);
      free(ptl_mait);
      ifofile->ptl_mait = NULL;
      return 0;
    }
    info_length = (ptl_mait->nr_of_vtss + 1) * sizeof(pf_level_t);
    pf_temp = (uint16_t *)malloc(info_length);
    if(!pf_temp) {
      free_ptl_mait(ptl_mait, i);
      ifofile->ptl_mait = NULL;
      return 0;
    }
    if(!(DVDReadBytes(ifofile->file, pf_temp, info_length))) {
      fprintf(stderr, "libdvdread: Unable to read PTL_MAIT table at index %d.\n",i);
      free(pf_temp);
      free_ptl_mait(ptl_mait, i);
      ifofile->ptl_mait = NULL;
      return 0;
    }
    for (j = 0; j < ((ptl_mait->nr_of_vtss + 1) * 8); j++) {
      B2N_16(pf_temp[j]);
    }
    ptl_mait->countries[i].pf_ptl_mai = (pf_level_t *)malloc(info_length);
    if(!ptl_mait->countries[i].pf_ptl_mai) {
      free(pf_temp);
      free_ptl_mait(ptl_mait, i);
      ifofile->ptl_mait = NULL;
      return 0;
    }
    { /* Transpose the array so we can use C indexing. */
      int level, vts;
      for(level = 0; level < PTL_MAIT_NUM_LEVEL; level++) {
        for(vts = 0; vts <= ptl_mait->nr_of_vtss; vts++) {
          ptl_mait->countries[i].pf_ptl_mai[vts][level] =
            pf_temp[(7-level)*(ptl_mait->nr_of_vtss+1) + vts];
        }
      }
      free(pf_temp);
    }
  }
  return 1;
}

void ifoFree_PTL_MAIT(ifo_handle_t *ifofile) {
  unsigned int i;

  if(!ifofile)
    return;

  if(ifofile->ptl_mait) {
    for(i = 0; i < ifofile->ptl_mait->nr_of_countries; i++) {
      free(ifofile->ptl_mait->countries[i].pf_ptl_mai);
    }
    free(ifofile->ptl_mait->countries);
    free(ifofile->ptl_mait);
    ifofile->ptl_mait = 0;
  }
}

int ifoRead_VTS_TMAPT(ifo_handle_t *ifofile) {
  vts_tmapt_t *vts_tmapt;
  uint32_t *vts_tmap_srp;
  unsigned int offset;
  int info_length;
  unsigned int i, j;

  if(!ifofile)
    return 0;

  if(!ifofile->vtsi_mat)
    return 0;

  if(ifofile->vtsi_mat->vts_tmapt == 0) { /* optional(?) */
    ifofile->vts_tmapt = NULL;
    fprintf(stderr,"Please send bug report - no VTS_TMAPT ?? \n");
    return 1;
  }

  offset = ifofile->vtsi_mat->vts_tmapt * DVD_BLOCK_LEN;

  if(!DVDFileSeek_(ifofile->file, offset))
    return 0;

  vts_tmapt = (vts_tmapt_t *)malloc(sizeof(vts_tmapt_t));
  if(!vts_tmapt)
    return 0;

  ifofile->vts_tmapt = vts_tmapt;

  if(!(DVDReadBytes(ifofile->file, vts_tmapt, VTS_TMAPT_SIZE))) {
    fprintf(stderr, "libdvdread: Unable to read VTS_TMAPT.\n");
    free(vts_tmapt);
    ifofile->vts_tmapt = NULL;
    return 0;
  }

  B2N_16(vts_tmapt->nr_of_tmaps);
  B2N_32(vts_tmapt->last_byte);

  CHECK_ZERO(vts_tmapt->zero_1);

  info_length = vts_tmapt->nr_of_tmaps * 4;

  vts_tmap_srp = (uint32_t *)malloc(info_length);
  if(!vts_tmap_srp) {
    free(vts_tmapt);
    ifofile->vts_tmapt = NULL;
    return 0;
  }

  vts_tmapt->tmap_offset = vts_tmap_srp;

  if(!(DVDReadBytes(ifofile->file, vts_tmap_srp, info_length))) {
    fprintf(stderr, "libdvdread: Unable to read VTS_TMAPT.\n");
    free(vts_tmap_srp);
    free(vts_tmapt);
    ifofile->vts_tmapt = NULL;
    return 0;
  }

  for (i = 0; i < vts_tmapt->nr_of_tmaps; i++) {
    B2N_32(vts_tmap_srp[i]);
  }


  info_length = vts_tmapt->nr_of_tmaps * sizeof(vts_tmap_t);

  vts_tmapt->tmap = (vts_tmap_t *)malloc(info_length);
  if(!vts_tmapt->tmap) {
    free(vts_tmap_srp);
    free(vts_tmapt);
    ifofile->vts_tmapt = NULL;
    return 0;
  }

  memset(vts_tmapt->tmap, 0, info_length); /* So ifoFree_VTS_TMAPT works. */

  for(i = 0; i < vts_tmapt->nr_of_tmaps; i++) {
    if(!DVDFileSeek_(ifofile->file, offset + vts_tmap_srp[i])) {
      ifoFree_VTS_TMAPT(ifofile);
      return 0;
    }

    if(!(DVDReadBytes(ifofile->file, &vts_tmapt->tmap[i], VTS_TMAP_SIZE))) {
      fprintf(stderr, "libdvdread: Unable to read VTS_TMAP.\n");
      ifoFree_VTS_TMAPT(ifofile);
      return 0;
    }

    B2N_16(vts_tmapt->tmap[i].nr_of_entries);
    CHECK_ZERO(vts_tmapt->tmap[i].zero_1);

    if(vts_tmapt->tmap[i].nr_of_entries == 0) { /* Early out if zero entries */
      vts_tmapt->tmap[i].map_ent = NULL;
      continue;
    }

    info_length = vts_tmapt->tmap[i].nr_of_entries * sizeof(map_ent_t);

    vts_tmapt->tmap[i].map_ent = (map_ent_t *)malloc(info_length);
    if(!vts_tmapt->tmap[i].map_ent) {
      ifoFree_VTS_TMAPT(ifofile);
      return 0;
    }

    if(!(DVDReadBytes(ifofile->file, vts_tmapt->tmap[i].map_ent, info_length))) {
      fprintf(stderr, "libdvdread: Unable to read VTS_TMAP_ENT.\n");
      ifoFree_VTS_TMAPT(ifofile);
      return 0;
    }

    for(j = 0; j < vts_tmapt->tmap[i].nr_of_entries; j++)
      B2N_32(vts_tmapt->tmap[i].map_ent[j]);
  }

  return 1;
}

void ifoFree_VTS_TMAPT(ifo_handle_t *ifofile) {
  unsigned int i;

  if(!ifofile)
    return;

  if(ifofile->vts_tmapt) {
    for(i = 0; i < ifofile->vts_tmapt->nr_of_tmaps; i++)
      if(ifofile->vts_tmapt->tmap[i].map_ent)
        free(ifofile->vts_tmapt->tmap[i].map_ent);
    free(ifofile->vts_tmapt->tmap);
    free(ifofile->vts_tmapt->tmap_offset);
    free(ifofile->vts_tmapt);
    ifofile->vts_tmapt = NULL;
  }
}


int ifoRead_TITLE_C_ADT(ifo_handle_t *ifofile) {

  if(!ifofile)
    return 0;

  if(!ifofile->vtsi_mat)
    return 0;

  if(ifofile->vtsi_mat->vts_c_adt == 0) /* mandatory */
    return 0;

  ifofile->vts_c_adt = (c_adt_t *)malloc(sizeof(c_adt_t));
  if(!ifofile->vts_c_adt)
    return 0;

  if(!ifoRead_C_ADT_internal(ifofile, ifofile->vts_c_adt,
                             ifofile->vtsi_mat->vts_c_adt)) {
    free(ifofile->vts_c_adt);
    ifofile->vts_c_adt = 0;
    return 0;
  }

  return 1;
}

int ifoRead_C_ADT(ifo_handle_t *ifofile) {
  unsigned int sector;

  if(!ifofile)
    return 0;

  if(ifofile->vmgi_mat) {
    if(ifofile->vmgi_mat->vmgm_c_adt == 0)
      return 1;
    sector = ifofile->vmgi_mat->vmgm_c_adt;
  } else if(ifofile->vtsi_mat) {
    if(ifofile->vtsi_mat->vtsm_c_adt == 0)
      return 1;
    sector = ifofile->vtsi_mat->vtsm_c_adt;
  } else {
    return 0;
  }

  ifofile->menu_c_adt = (c_adt_t *)malloc(sizeof(c_adt_t));
  if(!ifofile->menu_c_adt)
    return 0;

  if(!ifoRead_C_ADT_internal(ifofile, ifofile->menu_c_adt, sector)) {
    free(ifofile->menu_c_adt);
    ifofile->menu_c_adt = 0;
    return 0;
  }

  return 1;
}

static int ifoRead_C_ADT_internal(ifo_handle_t *ifofile,
                                  c_adt_t *c_adt, unsigned int sector) {
  int i, info_length;

  if(!DVDFileSeek_(ifofile->file, sector * DVD_BLOCK_LEN))
    return 0;

  if(!(DVDReadBytes(ifofile->file, c_adt, C_ADT_SIZE)))
    return 0;

  B2N_16(c_adt->nr_of_vobs);
  B2N_32(c_adt->last_byte);

  info_length = c_adt->last_byte + 1 - C_ADT_SIZE;

  CHECK_ZERO(c_adt->zero_1);
  /* assert(c_adt->nr_of_vobs > 0);
     Magic Knight Rayearth Daybreak is mastered very strange and has
     Titles with a VOBS that has no cells. */
  CHECK_VALUE(info_length % sizeof(cell_adr_t) == 0);

  /* assert(info_length / sizeof(cell_adr_t) >= c_adt->nr_of_vobs);
     Enemy of the State region 2 (de) has Titles where nr_of_vobs field
     is to high, they high ones are never referenced though. */
  if(info_length / sizeof(cell_adr_t) < c_adt->nr_of_vobs) {
    fprintf(stderr, "libdvdread: *C_ADT nr_of_vobs > available info entries\n");
    c_adt->nr_of_vobs = info_length / sizeof(cell_adr_t);
  }

  c_adt->cell_adr_table = (cell_adr_t *)malloc(info_length);
  if(!c_adt->cell_adr_table)
    return 0;

  if(info_length &&
     !(DVDReadBytes(ifofile->file, c_adt->cell_adr_table, info_length))) {
    free(c_adt->cell_adr_table);
    return 0;
  }

  for(i = 0; i < info_length/sizeof(cell_adr_t); i++) {
    B2N_16(c_adt->cell_adr_table[i].vob_id);
    B2N_32(c_adt->cell_adr_table[i].start_sector);
    B2N_32(c_adt->cell_adr_table[i].last_sector);

    CHECK_ZERO(c_adt->cell_adr_table[i].zero_1);
    CHECK_VALUE(c_adt->cell_adr_table[i].vob_id > 0);
    CHECK_VALUE(c_adt->cell_adr_table[i].vob_id <= c_adt->nr_of_vobs);
    CHECK_VALUE(c_adt->cell_adr_table[i].cell_id > 0);
    CHECK_VALUE(c_adt->cell_adr_table[i].start_sector <
                c_adt->cell_adr_table[i].last_sector);
  }

  return 1;
}


static void ifoFree_C_ADT_internal(c_adt_t *c_adt) {
  if(c_adt) {
    free(c_adt->cell_adr_table);
    free(c_adt);
  }
}

void ifoFree_C_ADT(ifo_handle_t *ifofile) {
  if(!ifofile)
    return;

  ifoFree_C_ADT_internal(ifofile->menu_c_adt);
  ifofile->menu_c_adt = 0;
}

void ifoFree_TITLE_C_ADT(ifo_handle_t *ifofile) {
  if(!ifofile)
    return;

  ifoFree_C_ADT_internal(ifofile->vts_c_adt);
  ifofile->vts_c_adt = 0;
}

int ifoRead_TITLE_VOBU_ADMAP(ifo_handle_t *ifofile) {
  if(!ifofile)
    return 0;

  if(!ifofile->vtsi_mat)
    return 0;

  if(ifofile->vtsi_mat->vts_vobu_admap == 0) /* mandatory */
    return 0;

  ifofile->vts_vobu_admap = (vobu_admap_t *)malloc(sizeof(vobu_admap_t));
  if(!ifofile->vts_vobu_admap)
    return 0;

  if(!ifoRead_VOBU_ADMAP_internal(ifofile, ifofile->vts_vobu_admap,
                                  ifofile->vtsi_mat->vts_vobu_admap)) {
    free(ifofile->vts_vobu_admap);
    ifofile->vts_vobu_admap = 0;
    return 0;
  }

  return 1;
}

int ifoRead_VOBU_ADMAP(ifo_handle_t *ifofile) {
  unsigned int sector;

  if(!ifofile)
    return 0;

  if(ifofile->vmgi_mat) {
    if(ifofile->vmgi_mat->vmgm_vobu_admap == 0)
      return 1;
    sector = ifofile->vmgi_mat->vmgm_vobu_admap;
  } else if(ifofile->vtsi_mat) {
    if(ifofile->vtsi_mat->vtsm_vobu_admap == 0)
      return 1;
    sector = ifofile->vtsi_mat->vtsm_vobu_admap;
  } else {
    return 0;
  }

  ifofile->menu_vobu_admap = (vobu_admap_t *)malloc(sizeof(vobu_admap_t));
  if(!ifofile->menu_vobu_admap)
    return 0;

  if(!ifoRead_VOBU_ADMAP_internal(ifofile, ifofile->menu_vobu_admap, sector)) {
    free(ifofile->menu_vobu_admap);
    ifofile->menu_vobu_admap = 0;
    return 0;
  }

  return 1;
}

static int ifoRead_VOBU_ADMAP_internal(ifo_handle_t *ifofile,
                                       vobu_admap_t *vobu_admap,
                                       unsigned int sector) {
  unsigned int i;
  int info_length;

  if(!DVDFileSeekForce_(ifofile->file, sector * DVD_BLOCK_LEN, sector))
    return 0;

  if(!(DVDReadBytes(ifofile->file, vobu_admap, VOBU_ADMAP_SIZE)))
    return 0;

  B2N_32(vobu_admap->last_byte);

  info_length = vobu_admap->last_byte + 1 - VOBU_ADMAP_SIZE;
  /* assert(info_length > 0);
     Magic Knight Rayearth Daybreak is mastered very strange and has
     Titles with a VOBS that has no VOBUs. */
  CHECK_VALUE(info_length % sizeof(uint32_t) == 0);

  vobu_admap->vobu_start_sectors = (uint32_t *)malloc(info_length);
  if(!vobu_admap->vobu_start_sectors) {
    return 0;
  }
  if(info_length &&
     !(DVDReadBytes(ifofile->file,
                    vobu_admap->vobu_start_sectors, info_length))) {
    free(vobu_admap->vobu_start_sectors);
    return 0;
  }

  for(i = 0; i < info_length/sizeof(uint32_t); i++)
    B2N_32(vobu_admap->vobu_start_sectors[i]);

  return 1;
}


static void ifoFree_VOBU_ADMAP_internal(vobu_admap_t *vobu_admap) {
  if(vobu_admap) {
    free(vobu_admap->vobu_start_sectors);
    free(vobu_admap);
  }
}

void ifoFree_VOBU_ADMAP(ifo_handle_t *ifofile) {
  if(!ifofile)
    return;

  ifoFree_VOBU_ADMAP_internal(ifofile->menu_vobu_admap);
  ifofile->menu_vobu_admap = 0;
}

void ifoFree_TITLE_VOBU_ADMAP(ifo_handle_t *ifofile) {
  if(!ifofile)
    return;

  ifoFree_VOBU_ADMAP_internal(ifofile->vts_vobu_admap);
  ifofile->vts_vobu_admap = 0;
}

int ifoRead_PGCIT(ifo_handle_t *ifofile) {

  if(!ifofile)
    return 0;

  if(!ifofile->vtsi_mat)
    return 0;

  if(ifofile->vtsi_mat->vts_pgcit == 0) /* mandatory */
    return 0;

  ifofile->vts_pgcit = (pgcit_t *)malloc(sizeof(pgcit_t));
  if(!ifofile->vts_pgcit)
    return 0;

  if(!ifoRead_PGCIT_internal(ifofile, ifofile->vts_pgcit,
                             ifofile->vtsi_mat->vts_pgcit * DVD_BLOCK_LEN)) {
    free(ifofile->vts_pgcit);
    ifofile->vts_pgcit = 0;
    return 0;
  }

  return 1;
}

static int ifoRead_PGCIT_internal(ifo_handle_t *ifofile, pgcit_t *pgcit,
                                  unsigned int offset) {
  int i, info_length;
  uint8_t *data, *ptr;

  if(!DVDFileSeek_(ifofile->file, offset))
    return 0;

  if(!(DVDReadBytes(ifofile->file, pgcit, PGCIT_SIZE)))
    return 0;

  B2N_16(pgcit->nr_of_pgci_srp);
  B2N_32(pgcit->last_byte);

  CHECK_ZERO(pgcit->zero_1);
  /* assert(pgcit->nr_of_pgci_srp != 0);
     Magic Knight Rayearth Daybreak is mastered very strange and has
     Titles with 0 PTTs. */
  CHECK_VALUE(pgcit->nr_of_pgci_srp < 10000); /* ?? seen max of 1338 */

  info_length = pgcit->nr_of_pgci_srp * PGCI_SRP_SIZE;
  data = malloc(info_length);
  if(!data)
    return 0;

  if(info_length && !(DVDReadBytes(ifofile->file, data, info_length))) {
    free(data);
    return 0;
  }

  pgcit->pgci_srp = malloc(pgcit->nr_of_pgci_srp * sizeof(pgci_srp_t));
  if(!pgcit->pgci_srp) {
    free(data);
    return 0;
  }
  ptr = data;
  for(i = 0; i < pgcit->nr_of_pgci_srp; i++) {
    memcpy(&pgcit->pgci_srp[i], ptr, PGCI_SRP_SIZE);
    ptr += PGCI_SRP_SIZE;
    read_pgci_srp(&pgcit->pgci_srp[i]);
    CHECK_VALUE(pgcit->pgci_srp[i].unknown1 == 0);
  }
  free(data);

  for(i = 0; i < pgcit->nr_of_pgci_srp; i++)
    CHECK_VALUE(pgcit->pgci_srp[i].pgc_start_byte + PGC_SIZE <= pgcit->last_byte+1);

  for(i = 0; i < pgcit->nr_of_pgci_srp; i++) {
    pgcit->pgci_srp[i].pgc = malloc(sizeof(pgc_t));
    if(!pgcit->pgci_srp[i].pgc) {
      int j;
      for(j = 0; j < i; j++) {
        ifoFree_PGC(pgcit->pgci_srp[j].pgc);
        free(pgcit->pgci_srp[j].pgc);
      }
      goto fail;
    }
    if(!ifoRead_PGC(ifofile, pgcit->pgci_srp[i].pgc,
                    offset + pgcit->pgci_srp[i].pgc_start_byte)) {
      int j;
      for(j = 0; j < i; j++) {
        ifoFree_PGC(pgcit->pgci_srp[j].pgc);
        free(pgcit->pgci_srp[j].pgc);
      }
      goto fail;
    }
  }

  return 1;
fail:
  free(pgcit->pgci_srp);
  pgcit->pgci_srp = NULL;
  return 0;
}

static void ifoFree_PGCIT_internal(pgcit_t *pgcit) {
  if(pgcit) {
    int i;
    for(i = 0; i < pgcit->nr_of_pgci_srp; i++)
      ifoFree_PGC(pgcit->pgci_srp[i].pgc);
    free(pgcit->pgci_srp);
  }
}

void ifoFree_PGCIT(ifo_handle_t *ifofile) {
  if(!ifofile)
    return;

  if(ifofile->vts_pgcit) {
    ifoFree_PGCIT_internal(ifofile->vts_pgcit);
    free(ifofile->vts_pgcit);
    ifofile->vts_pgcit = 0;
  }
}


int ifoRead_PGCI_UT(ifo_handle_t *ifofile) {
  pgci_ut_t *pgci_ut;
  unsigned int sector;
  unsigned int i;
  int info_length;
  uint8_t *data, *ptr;

  if(!ifofile)
    return 0;

  if(ifofile->vmgi_mat) {
    if(ifofile->vmgi_mat->vmgm_pgci_ut == 0)
      return 1;
    sector = ifofile->vmgi_mat->vmgm_pgci_ut;
  } else if(ifofile->vtsi_mat) {
    if(ifofile->vtsi_mat->vtsm_pgci_ut == 0)
      return 1;
    sector = ifofile->vtsi_mat->vtsm_pgci_ut;
  } else {
    return 0;
  }

  ifofile->pgci_ut = (pgci_ut_t *)malloc(sizeof(pgci_ut_t));
  if(!ifofile->pgci_ut)
    return 0;

  if(!DVDFileSeek_(ifofile->file, sector * DVD_BLOCK_LEN)) {
    free(ifofile->pgci_ut);
    ifofile->pgci_ut = 0;
    return 0;
  }

  if(!(DVDReadBytes(ifofile->file, ifofile->pgci_ut, PGCI_UT_SIZE))) {
    free(ifofile->pgci_ut);
    ifofile->pgci_ut = 0;
    return 0;
  }

  pgci_ut = ifofile->pgci_ut;

  B2N_16(pgci_ut->nr_of_lus);
  B2N_32(pgci_ut->last_byte);

  CHECK_ZERO(pgci_ut->zero_1);
  CHECK_VALUE(pgci_ut->nr_of_lus != 0);
  CHECK_VALUE(pgci_ut->nr_of_lus < 100); /* ?? 3-4 ? */
  CHECK_VALUE((uint32_t)pgci_ut->nr_of_lus * PGCI_LU_SIZE < pgci_ut->last_byte);

  info_length = pgci_ut->nr_of_lus * PGCI_LU_SIZE;
  data = malloc(info_length);
  if(!data) {
    free(pgci_ut);
    ifofile->pgci_ut = 0;
    return 0;
  }
  if(!(DVDReadBytes(ifofile->file, data, info_length))) {
    free(data);
    free(pgci_ut);
    ifofile->pgci_ut = 0;
    return 0;
  }

  pgci_ut->lu = malloc(pgci_ut->nr_of_lus * sizeof(pgci_lu_t));
  if(!pgci_ut->lu) {
    free(data);
    free(pgci_ut);
    ifofile->pgci_ut = 0;
    return 0;
  }
  ptr = data;
  for(i = 0; i < pgci_ut->nr_of_lus; i++) {
    memcpy(&pgci_ut->lu[i], ptr, PGCI_LU_SIZE);
    ptr += PGCI_LU_SIZE;
    B2N_16(pgci_ut->lu[i].lang_code);
    B2N_32(pgci_ut->lu[i].lang_start_byte);
  }
  free(data);

  for(i = 0; i < pgci_ut->nr_of_lus; i++) {
    /* Maybe this is only defined for v1.1 and later titles? */
    /* If the bits in 'lu[i].exists' are enumerated abcd efgh then:
       VTS_x_yy.IFO        VIDEO_TS.IFO
       a == 0x83 "Root"         0x82 "Title"
       b == 0x84 "Subpicture"
       c == 0x85 "Audio"
       d == 0x86 "Angle"
       e == 0x87 "PTT"
    */
    CHECK_VALUE((pgci_ut->lu[i].exists & 0x07) == 0);
  }

  for(i = 0; i < pgci_ut->nr_of_lus; i++) {
    pgci_ut->lu[i].pgcit = malloc(sizeof(pgcit_t));
    if(!pgci_ut->lu[i].pgcit) {
      unsigned int j;
      for(j = 0; j < i; j++) {
        ifoFree_PGCIT_internal(pgci_ut->lu[j].pgcit);
        free(pgci_ut->lu[j].pgcit);
      }
      free(pgci_ut->lu);
      free(pgci_ut);
      ifofile->pgci_ut = 0;
      return 0;
    }
    if(!ifoRead_PGCIT_internal(ifofile, pgci_ut->lu[i].pgcit,
                               sector * DVD_BLOCK_LEN
                               + pgci_ut->lu[i].lang_start_byte)) {
      unsigned int j;
      for(j = 0; j < i; j++) {
        ifoFree_PGCIT_internal(pgci_ut->lu[j].pgcit);
        free(pgci_ut->lu[j].pgcit);
      }
      free(pgci_ut->lu[i].pgcit);
      free(pgci_ut->lu);
      free(pgci_ut);
      ifofile->pgci_ut = 0;
      return 0;
    }
    /* FIXME: Iterate and verify that all menus that should exists accordingly
     * to pgci_ut->lu[i].exists really do? */
  }

  return 1;
}


void ifoFree_PGCI_UT(ifo_handle_t *ifofile) {
  unsigned int i;

  if(!ifofile)
    return;

  if(ifofile->pgci_ut) {
    for(i = 0; i < ifofile->pgci_ut->nr_of_lus; i++) {
      ifoFree_PGCIT_internal(ifofile->pgci_ut->lu[i].pgcit);
      free(ifofile->pgci_ut->lu[i].pgcit);
    }
    free(ifofile->pgci_ut->lu);
    free(ifofile->pgci_ut);
    ifofile->pgci_ut = 0;
  }
}

static int ifoRead_VTS_ATTRIBUTES(ifo_handle_t *ifofile,
                                  vts_attributes_t *vts_attributes,
                                  unsigned int offset) {
  unsigned int i;

  if(!DVDFileSeek_(ifofile->file, offset))
    return 0;

  if(!(DVDReadBytes(ifofile->file, vts_attributes, sizeof(vts_attributes_t))))
    return 0;

  read_video_attr(&vts_attributes->vtsm_vobs_attr);
  read_video_attr(&vts_attributes->vtstt_vobs_video_attr);
  read_audio_attr(&vts_attributes->vtsm_audio_attr);
  for(i=0; i<8; i++)
    read_audio_attr(&vts_attributes->vtstt_audio_attr[i]);
  read_subp_attr(&vts_attributes->vtsm_subp_attr);
  for(i=0; i<32; i++)
    read_subp_attr(&vts_attributes->vtstt_subp_attr[i]);
  B2N_32(vts_attributes->last_byte);
  B2N_32(vts_attributes->vts_cat);

  CHECK_ZERO(vts_attributes->zero_1);
  CHECK_ZERO(vts_attributes->zero_2);
  CHECK_ZERO(vts_attributes->zero_3);
  CHECK_ZERO(vts_attributes->zero_4);
  CHECK_ZERO(vts_attributes->zero_5);
  CHECK_ZERO(vts_attributes->zero_6);
  CHECK_ZERO(vts_attributes->zero_7);
  CHECK_VALUE(vts_attributes->nr_of_vtsm_audio_streams <= 1);
  CHECK_VALUE(vts_attributes->nr_of_vtsm_subp_streams <= 1);
  CHECK_VALUE(vts_attributes->nr_of_vtstt_audio_streams <= 8);
  for(i = vts_attributes->nr_of_vtstt_audio_streams; i < 8; i++)
    CHECK_ZERO(vts_attributes->vtstt_audio_attr[i]);
  CHECK_VALUE(vts_attributes->nr_of_vtstt_subp_streams <= 32);
  {
    unsigned int nr_coded;
    CHECK_VALUE(vts_attributes->last_byte + 1 >= VTS_ATTRIBUTES_MIN_SIZE);
    nr_coded = (vts_attributes->last_byte + 1 - VTS_ATTRIBUTES_MIN_SIZE)/6;
    /* This is often nr_coded = 70, how do you know how many there really are? */
    if(nr_coded > 32) { /* We haven't read more from disk/file anyway */
      nr_coded = 32;
    }
    CHECK_VALUE(vts_attributes->nr_of_vtstt_subp_streams <= nr_coded);
    for(i = vts_attributes->nr_of_vtstt_subp_streams; i < nr_coded; i++)
      CHECK_ZERO(vts_attributes->vtstt_subp_attr[i]);
  }

  return 1;
}



int ifoRead_VTS_ATRT(ifo_handle_t *ifofile) {
  vts_atrt_t *vts_atrt;
  unsigned int i, info_length, sector;
  uint32_t *data;

  if(!ifofile)
    return 0;

  if(!ifofile->vmgi_mat)
    return 0;

  if(ifofile->vmgi_mat->vts_atrt == 0) /* mandatory */
    return 0;

  sector = ifofile->vmgi_mat->vts_atrt;
  if(!DVDFileSeek_(ifofile->file, sector * DVD_BLOCK_LEN))
    return 0;

  vts_atrt = (vts_atrt_t *)malloc(sizeof(vts_atrt_t));
  if(!vts_atrt)
    return 0;

  ifofile->vts_atrt = vts_atrt;

  if(!(DVDReadBytes(ifofile->file, vts_atrt, VTS_ATRT_SIZE))) {
    free(vts_atrt);
    ifofile->vts_atrt = 0;
    return 0;
  }

  B2N_16(vts_atrt->nr_of_vtss);
  B2N_32(vts_atrt->last_byte);

  CHECK_ZERO(vts_atrt->zero_1);
  CHECK_VALUE(vts_atrt->nr_of_vtss != 0);
  CHECK_VALUE(vts_atrt->nr_of_vtss < 100); /* ?? */
  CHECK_VALUE((uint32_t)vts_atrt->nr_of_vtss * (4 + VTS_ATTRIBUTES_MIN_SIZE) +
              VTS_ATRT_SIZE < vts_atrt->last_byte + 1);

  info_length = vts_atrt->nr_of_vtss * sizeof(uint32_t);
  data = (uint32_t *)malloc(info_length);
  if(!data) {
    free(vts_atrt);
    ifofile->vts_atrt = 0;
    return 0;
  }

  vts_atrt->vts_atrt_offsets = data;

  if(!(DVDReadBytes(ifofile->file, data, info_length))) {
    free(data);
    free(vts_atrt);
    ifofile->vts_atrt = 0;
    return 0;
  }

  for(i = 0; i < vts_atrt->nr_of_vtss; i++) {
    B2N_32(data[i]);
    CHECK_VALUE(data[i] + VTS_ATTRIBUTES_MIN_SIZE < vts_atrt->last_byte + 1);
  }

  info_length = vts_atrt->nr_of_vtss * sizeof(vts_attributes_t);
  vts_atrt->vts = (vts_attributes_t *)malloc(info_length);
  if(!vts_atrt->vts) {
    free(data);
    free(vts_atrt);
    ifofile->vts_atrt = 0;
    return 0;
  }
  for(i = 0; i < vts_atrt->nr_of_vtss; i++) {
    unsigned int offset = data[i];
    if(!ifoRead_VTS_ATTRIBUTES(ifofile, &(vts_atrt->vts[i]),
                               (sector * DVD_BLOCK_LEN) + offset)) {
      free(data);
      free(vts_atrt);
      ifofile->vts_atrt = 0;
      return 0;
    }

    /* This assert cant be in ifoRead_VTS_ATTRIBUTES */
    CHECK_VALUE(offset + vts_atrt->vts[i].last_byte <= vts_atrt->last_byte + 1);
    /* Is this check correct? */
  }

  return 1;
}


void ifoFree_VTS_ATRT(ifo_handle_t *ifofile) {
  if(!ifofile)
    return;

  if(ifofile->vts_atrt) {
    free(ifofile->vts_atrt->vts);
    free(ifofile->vts_atrt->vts_atrt_offsets);
    free(ifofile->vts_atrt);
    ifofile->vts_atrt = 0;
  }
}


int ifoRead_TXTDT_MGI(ifo_handle_t *ifofile) {
  txtdt_mgi_t *txtdt_mgi;

  if(!ifofile)
    return 0;

  if(!ifofile->vmgi_mat)
    return 0;

  /* Return successfully if there is nothing to read. */
  if(ifofile->vmgi_mat->txtdt_mgi == 0)
    return 1;

  if(!DVDFileSeek_(ifofile->file,
                   ifofile->vmgi_mat->txtdt_mgi * DVD_BLOCK_LEN))
    return 0;

  txtdt_mgi = (txtdt_mgi_t *)malloc(sizeof(txtdt_mgi_t));
  if(!txtdt_mgi) {
    return 0;
  }
  ifofile->txtdt_mgi = txtdt_mgi;

  if(!(DVDReadBytes(ifofile->file, txtdt_mgi, TXTDT_MGI_SIZE))) {
    fprintf(stderr, "libdvdread: Unable to read TXTDT_MGI.\n");
    free(txtdt_mgi);
    ifofile->txtdt_mgi = 0;
    return 0;
  }

  /* fprintf(stderr, "-- Not done yet --\n"); */
  return 1;
}

void ifoFree_TXTDT_MGI(ifo_handle_t *ifofile) {
  if(!ifofile)
    return;

  if(ifofile->txtdt_mgi) {
    free(ifofile->txtdt_mgi);
    ifofile->txtdt_mgi = 0;
  }
}
