gstreamer/ext/dvdread/dvdreadsrc.c

/* GStreamer
 * Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

/**
 * Copyright (C) 2001 Billy Biggs <vektor@dumbterm.net>.
 *
 * This program 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.
 *
 * This program 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 this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/ioctl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <dirent.h>
#include <errno.h>
//#include <linux/cdrom.h>
#include <assert.h>

#include <dvdreadsrc.h>

#include <dvdread/dvd_reader.h>
#include <dvdread/ifo_types.h>
#include <dvdread/ifo_read.h>
#include <dvdread/nav_read.h>
#include <dvdread/nav_print.h>

struct _DVDReadSrcPrivate
{
  GstElement element;
  /* pads */
  GstPad *srcpad;

  /* location */
  gchar *location;

  gboolean new_seek;

  int title, chapter, angle;
  int pgc_id, start_cell, cur_cell, cur_pack;
  int ttn, pgn, next_cell;
  dvd_reader_t *dvd;
  dvd_file_t *dvd_title;
  ifo_handle_t *vmg_file;
  tt_srpt_t *tt_srpt;
  ifo_handle_t *vts_file;
  vts_ptt_srpt_t *vts_ptt_srpt;
  pgc_t *cur_pgc;
};


GstElementDetails dvdreadsrc_details = {
  "DVD Source",
  "Source/File/DVD",
  "Access a DVD title/chapter/angle using libdvdread",
  "Erik Walthinsen <omega@cse.ogi.edu>",
};


/* DVDReadSrc signals and args */
enum
{
  /* FILL ME */
  LAST_SIGNAL
};

enum
{
  ARG_0,
  ARG_LOCATION,
  ARG_TITLE,
  ARG_CHAPTER,
  ARG_ANGLE
};

static void dvdreadsrc_base_init (gpointer g_class);
static void dvdreadsrc_class_init (DVDReadSrcClass * klass);
static void dvdreadsrc_init (DVDReadSrc * dvdreadsrc);

static void dvdreadsrc_set_property (GObject * object, guint prop_id,
    const GValue * value, GParamSpec * pspec);
static void dvdreadsrc_get_property (GObject * object, guint prop_id,
    GValue * value, GParamSpec * pspec);

/*static GstData *	dvdreadsrc_get		(GstPad *pad); */
static void dvdreadsrc_loop (GstElement * element);

/*static GstBuffer *	dvdreadsrc_get_region	(GstPad *pad,gulong offset,gulong size); */

static GstElementStateReturn dvdreadsrc_change_state (GstElement * element);


static GstElementClass *parent_class = NULL;

/*static guint dvdreadsrc_signals[LAST_SIGNAL] = { 0 }; */

GType
dvdreadsrc_get_type (void)
{
  static GType dvdreadsrc_type = 0;

  if (!dvdreadsrc_type) {
    static const GTypeInfo dvdreadsrc_info = {
      sizeof (DVDReadSrcClass),
      dvdreadsrc_base_init,
      NULL,
      (GClassInitFunc) dvdreadsrc_class_init,
      NULL,
      NULL,
      sizeof (DVDReadSrc),
      0,
      (GInstanceInitFunc) dvdreadsrc_init,
    };

    dvdreadsrc_type =
        g_type_register_static (GST_TYPE_ELEMENT, "DVDReadSrc",
        &dvdreadsrc_info, 0);
  }
  return dvdreadsrc_type;
}

static void
dvdreadsrc_base_init (gpointer g_class)
{
  GstElementClass *element_class = GST_ELEMENT_CLASS (g_class);

  gst_element_class_set_details (element_class, &dvdreadsrc_details);
}

static void
dvdreadsrc_class_init (DVDReadSrcClass * klass)
{
  GObjectClass *gobject_class;
  GstElementClass *gstelement_class;

  gobject_class = (GObjectClass *) klass;
  gstelement_class = (GstElementClass *) klass;

  parent_class = g_type_class_ref (GST_TYPE_ELEMENT);

  g_object_class_install_property (G_OBJECT_CLASS (klass), ARG_LOCATION,
      g_param_spec_string ("location", "location", "location",
          NULL, G_PARAM_READWRITE));
  g_object_class_install_property (G_OBJECT_CLASS (klass), ARG_TITLE,
      g_param_spec_int ("title", "title", "title",
          0, G_MAXINT, 0, G_PARAM_READWRITE));
  g_object_class_install_property (G_OBJECT_CLASS (klass), ARG_CHAPTER,
      g_param_spec_int ("chapter", "chapter", "chapter",
          0, G_MAXINT, 0, G_PARAM_READWRITE));
  g_object_class_install_property (G_OBJECT_CLASS (klass), ARG_ANGLE,
      g_param_spec_int ("angle", "angle", "angle",
          0, G_MAXINT, 0, G_PARAM_READWRITE));

  gobject_class->set_property = GST_DEBUG_FUNCPTR (dvdreadsrc_set_property);
  gobject_class->get_property = GST_DEBUG_FUNCPTR (dvdreadsrc_get_property);

  gstelement_class->change_state = dvdreadsrc_change_state;
}

static void
dvdreadsrc_init (DVDReadSrc * dvdreadsrc)
{
  dvdreadsrc->priv = g_new (DVDReadSrcPrivate, 1);
  dvdreadsrc->priv->srcpad = gst_pad_new ("src", GST_PAD_SRC);
  gst_element_add_pad (GST_ELEMENT (dvdreadsrc), dvdreadsrc->priv->srcpad);
  gst_element_set_loop_function (GST_ELEMENT (dvdreadsrc),
      GST_DEBUG_FUNCPTR (dvdreadsrc_loop));

  dvdreadsrc->priv->location = g_strdup ("/dev/dvd");
  dvdreadsrc->priv->new_seek = FALSE;
  dvdreadsrc->priv->title = 1;
  dvdreadsrc->priv->chapter = 1;
  dvdreadsrc->priv->angle = 1;
}

/* FIXME: this code is not being used */
#ifdef PLEASEFIXTHISCODE
static void
dvdreadsrc_destroy (DVDReadSrc * dvdreadsrc)
{
  /* FIXME */
  g_print ("FIXME\n");
  g_free (dvdreadsrc->priv);
}
#endif

static void
dvdreadsrc_set_property (GObject * object, guint prop_id, const GValue * value,
    GParamSpec * pspec)
{
  DVDReadSrc *src;
  DVDReadSrcPrivate *priv;

  /* it's not null if we got it, but it might not be ours */
  g_return_if_fail (GST_IS_DVDREADSRC (object));

  src = DVDREADSRC (object);
  priv = src->priv;

  switch (prop_id) {
    case ARG_LOCATION:
      /* the element must be stopped in order to do this */
      /*g_return_if_fail(!GST_FLAG_IS_SET(src,GST_STATE_RUNNING)); */

      if (priv->location)
        g_free (priv->location);
      /* clear the filename if we get a NULL (is that possible?) */
      if (g_value_get_string (value) == NULL)
        priv->location = g_strdup ("/dev/dvd");
      /* otherwise set the new filename */
      else
        priv->location = g_strdup (g_value_get_string (value));
      break;
    case ARG_TITLE:
      priv->title = g_value_get_int (value) - 1;
      priv->new_seek = TRUE;
      break;
    case ARG_CHAPTER:
      priv->chapter = g_value_get_int (value) - 1;
      priv->new_seek = TRUE;
      break;
    case ARG_ANGLE:
      priv->angle = g_value_get_int (value) - 1;
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }

}

static void
dvdreadsrc_get_property (GObject * object, guint prop_id, GValue * value,
    GParamSpec * pspec)
{
  DVDReadSrc *src;
  DVDReadSrcPrivate *priv;

  /* it's not null if we got it, but it might not be ours */
  g_return_if_fail (GST_IS_DVDREADSRC (object));

  src = DVDREADSRC (object);
  priv = src->priv;

  switch (prop_id) {
    case ARG_LOCATION:
      g_value_set_string (value, priv->location);
      break;
    case ARG_TITLE:
      g_value_set_int (value, priv->title + 1);
      break;
    case ARG_CHAPTER:
      g_value_set_int (value, priv->chapter + 1);
      break;
    case ARG_ANGLE:
      g_value_set_int (value, priv->angle + 1);
      break;
    default:
      G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
      break;
  }
}

/**
 * Returns true if the pack is a NAV pack.  This check is clearly insufficient,
 * and sometimes we incorrectly think that valid other packs are NAV packs.  I
 * need to make this stronger.
 */
static int
is_nav_pack (unsigned char *buffer)
{
  return (buffer[41] == 0xbf && buffer[1027] == 0xbf);
}

static int
_open (DVDReadSrcPrivate * priv, const gchar * location)
{
  g_return_val_if_fail (priv != NULL, -1);
  g_return_val_if_fail (location != NULL, -1);

  /**
   * Open the disc.
   */
  priv->dvd = DVDOpen (location);
  if (!priv->dvd) {
    fprintf (stderr, "Couldn't open DVD: %s\n", location);
    return -1;
  }


  /**
   * Load the video manager to find out the information about the titles on
   * this disc.
   */
  priv->vmg_file = ifoOpen (priv->dvd, 0);
  if (!priv->vmg_file) {
    fprintf (stderr, "Can't open VMG info.\n");
    DVDClose (priv->dvd);
    return -1;
  }
  priv->tt_srpt = priv->vmg_file->tt_srpt;

  return 0;
}

static int
_close (DVDReadSrcPrivate * priv)
{
  ifoClose (priv->vts_file);
  ifoClose (priv->vmg_file);
  DVDCloseFile (priv->dvd_title);
  DVDClose (priv->dvd);
  return 0;
}

static int
_seek (DVDReadSrcPrivate * priv, int title, int chapter, int angle)
{
    /**
     * Make sure our title number is valid.
     */
  fprintf (stderr, "There are %d titles on this DVD.\n",
      priv->tt_srpt->nr_of_srpts);
  if (title < 0 || title >= priv->tt_srpt->nr_of_srpts) {
    fprintf (stderr, "Invalid title %d.\n", title + 1);
    ifoClose (priv->vmg_file);
    DVDClose (priv->dvd);
    return -1;
  }


    /**
     * Make sure the chapter number is valid for this title.
     */
  fprintf (stderr, "There are %d chapters in this title.\n",
      priv->tt_srpt->title[title].nr_of_ptts);

  if (chapter < 0 || chapter >= priv->tt_srpt->title[title].nr_of_ptts) {
    fprintf (stderr, "Invalid chapter %d\n", chapter + 1);
    ifoClose (priv->vmg_file);
    DVDClose (priv->dvd);
    return -1;
  }


    /**
     * Make sure the angle number is valid for this title.
     */
  fprintf (stderr, "There are %d angles in this title.\n",
      priv->tt_srpt->title[title].nr_of_angles);
  if (angle < 0 || angle >= priv->tt_srpt->title[title].nr_of_angles) {
    fprintf (stderr, "Invalid angle %d\n", angle + 1);
    ifoClose (priv->vmg_file);
    DVDClose (priv->dvd);
    return -1;
  }


    /**
     * Load the VTS information for the title set our title is in.
     */
  priv->vts_file =
      ifoOpen (priv->dvd, priv->tt_srpt->title[title].title_set_nr);
  if (!priv->vts_file) {
    fprintf (stderr, "Can't open the title %d info file.\n",
        priv->tt_srpt->title[title].title_set_nr);
    ifoClose (priv->vmg_file);
    DVDClose (priv->dvd);
    return -1;
  }


    /**
     * Determine which program chain we want to watch.  This is based on the
     * chapter number.
     */
  priv->ttn = priv->tt_srpt->title[title].vts_ttn;
  priv->vts_ptt_srpt = priv->vts_file->vts_ptt_srpt;
  priv->pgc_id = priv->vts_ptt_srpt->title[priv->ttn - 1].ptt[chapter].pgcn;
  priv->pgn = priv->vts_ptt_srpt->title[priv->ttn - 1].ptt[chapter].pgn;
  priv->cur_pgc = priv->vts_file->vts_pgcit->pgci_srp[priv->pgc_id - 1].pgc;
  priv->start_cell = priv->cur_pgc->program_map[priv->pgn - 1] - 1;


    /**
     * We've got enough info, time to open the title set data.
     */
  priv->dvd_title =
      DVDOpenFile (priv->dvd, priv->tt_srpt->title[title].title_set_nr,
      DVD_READ_TITLE_VOBS);
  if (!priv->dvd_title) {
    fprintf (stderr, "Can't open title VOBS (VTS_%02d_1.VOB).\n",
        priv->tt_srpt->title[title].title_set_nr);
    ifoClose (priv->vts_file);
    ifoClose (priv->vmg_file);
    DVDClose (priv->dvd);
    return -1;
  }

  return 0;
}

static void
dvdreadsrc_loop (GstElement * element)
{
  DVDReadSrc *dvdreadsrc;
  DVDReadSrcPrivate *priv;

  g_return_if_fail (element != NULL);
  g_return_if_fail (GST_IS_DVDREADSRC (element));

  dvdreadsrc = DVDREADSRC (element);
  priv = dvdreadsrc->priv;
  g_return_if_fail (GST_FLAG_IS_SET (dvdreadsrc, DVDREADSRC_OPEN));

  /**
   * Playback by cell in this pgc, starting at the cell for our chapter.
   */
  priv->next_cell = priv->start_cell;
  for (priv->cur_cell = priv->start_cell;
      priv->next_cell < priv->cur_pgc->nr_of_cells;) {

    priv->cur_cell = priv->next_cell;

    /* Check if we're entering an angle block. */
    if (priv->cur_pgc->cell_playback[priv->cur_cell].block_type
        == BLOCK_TYPE_ANGLE_BLOCK) {
      int i;

      priv->cur_cell += priv->angle;
      for (i = 0;; ++i) {
        if (priv->cur_pgc->cell_playback[priv->cur_cell + i].block_mode
            == BLOCK_MODE_LAST_CELL) {
          priv->next_cell = priv->cur_cell + i + 1;
          break;
        }
      }
    } else {
      priv->next_cell = priv->cur_cell + 1;
    }


      /**
       * We loop until we're out of this cell.
       */
    for (priv->cur_pack =
        priv->cur_pgc->cell_playback[priv->cur_cell].first_sector;
        priv->cur_pack <
        priv->cur_pgc->cell_playback[priv->cur_cell].last_sector;) {

      dsi_t dsi_pack;
      unsigned int next_vobu, next_ilvu_start, cur_output_size;
      GstBuffer *buf;
      unsigned char *data;
      int len;

      /* create the buffer */
      /* FIXME: should eventually use a bufferpool for this */
      buf = gst_buffer_new ();
      g_return_if_fail (buf);

      /* allocate the space for the buffer data */
      data = g_malloc (1024 * DVD_VIDEO_LB_LEN);
      GST_BUFFER_DATA (buf) = data;

      g_return_if_fail (GST_BUFFER_DATA (buf) != NULL);

          /**
           * Read NAV packet.
           */
      len = DVDReadBlocks (priv->dvd_title, priv->cur_pack, 1, data);
      if (len == 0) {
        fprintf (stderr, "Read failed for block %d\n", priv->cur_pack);
        _close (priv);
        gst_element_set_eos (GST_ELEMENT (dvdreadsrc));
        return;
      }
      assert (is_nav_pack (data));


          /**
           * Parse the contained dsi packet.
           */
      navRead_DSI (&dsi_pack, &(data[DSI_START_BYTE]));
      assert (priv->cur_pack == dsi_pack.dsi_gi.nv_pck_lbn);
      /*navPrint_DSI(&dsi_pack); */


          /**
           * Determine where we go next.  These values are the ones we mostly
           * care about.
           */
      next_ilvu_start = priv->cur_pack
          + dsi_pack.sml_agli.data[priv->angle].address;
      cur_output_size = dsi_pack.dsi_gi.vobu_ea;


          /**
           * If we're not at the end of this cell, we can determine the next
           * VOBU to display using the VOBU_SRI information section of the
           * DSI.  Using this value correctly follows the current angle,
           * avoiding the doubled scenes in The Matrix, and makes our life
           * really happy.
           *
           * Otherwise, we set our next address past the end of this cell to
           * force the code above to go to the next cell in the program.
           */
      if (dsi_pack.vobu_sri.next_vobu != SRI_END_OF_CELL) {
        next_vobu = priv->cur_pack + (dsi_pack.vobu_sri.next_vobu & 0x7fffffff);
      } else {
        next_vobu = priv->cur_pack + cur_output_size + 1;
      }

      assert (cur_output_size < 1024);
      priv->cur_pack++;

          /**
           * Read in and output cursize packs.
           */
      len = DVDReadBlocks (priv->dvd_title, priv->cur_pack,
          cur_output_size, data);
      if (len != cur_output_size) {
        fprintf (stderr, "Read failed for %d blocks at %d\n",
            cur_output_size, priv->cur_pack);
        _close (priv);
        gst_element_set_eos (GST_ELEMENT (dvdreadsrc));
        return;
      }

      GST_BUFFER_SIZE (buf) = cur_output_size * DVD_VIDEO_LB_LEN;
      gst_pad_push (priv->srcpad, GST_DATA (buf));
      priv->cur_pack = next_vobu;
    }
  }
}

#if 0
static int
_read (DVDReadSrcPrivate * priv, int angle, int new_seek, GstBuffer * buf)
{
  unsigned char *data;

  data = GST_BUFFER_DATA (buf);

    /**
     * Playback by cell in this pgc, starting at the cell for our chapter.
     */
  if (new_seek) {
    priv->next_cell = priv->start_cell;
    priv->cur_cell = priv->start_cell;
  }
  if (priv->next_cell < priv->cur_pgc->nr_of_cells) {

    priv->cur_cell = priv->next_cell;

    /* Check if we're entering an angle block. */
    if (priv->cur_pgc->cell_playback[priv->cur_cell].block_type
        == BLOCK_TYPE_ANGLE_BLOCK) {
      int i;

      priv->cur_cell += angle;
      for (i = 0;; ++i) {
        if (priv->cur_pgc->cell_playback[priv->cur_cell + i].block_mode
            == BLOCK_MODE_LAST_CELL) {
          priv->next_cell = priv->cur_cell + i + 1;
          break;
        }
      }
    } else {
      priv->next_cell = priv->cur_cell + 1;
    }


        /**
         * We loop until we're out of this cell.
         */
    if (priv->new_cell) {
      priv->cur_pack =
          priv->cur_pgc->cell_playback[priv->cur_cell].first_sector;
      priv->new_cell = FALSE;
    }

    if (priv->cur_pack <
        priv->cur_pgc->cell_playback[priv->cur_cell].last_sector;) {

      dsi_t dsi_pack;
      unsigned int next_vobu, next_ilvu_start, cur_output_size;
      int len;


            /**
             * Read NAV packet.
             */
      len = DVDReadBlocks (priv->title, priv->cur_pack, 1, data);
      if (len == 0) {
        fprintf (stderr, "Read failed for block %d\n", priv->cur_pack);
        _close (priv);
        return -1;
      }
      assert (is_nav_pack (data));


            /**
             * Parse the contained dsi packet.
             */
      navRead_DSI (&dsi_pack, &(data[DSI_START_BYTE]), sizeof (dsi_t));
      assert (priv->cur_pack == dsi_pack.dsi_gi.nv_pck_lbn);


            /**
             * Determine where we go next.  These values are the ones we mostly
             * care about.
             */
      next_ilvu_start = priv->cur_pack + dsi_pack.sml_agli.data[angle].address;
      cur_output_size = dsi_pack.dsi_gi.vobu_ea;


            /**
             * If we're not at the end of this cell, we can determine the next
             * VOBU to display using the VOBU_SRI information section of the
             * DSI.  Using this value correctly follows the current angle,
             * avoiding the doubled scenes in The Matrix, and makes our life
             * really happy.
             *
             * Otherwise, we set our next address past the end of this cell to
             * force the code above to go to the next cell in the program.
             */
      if (dsi_pack.vobu_sri.next_vobu != SRI_END_OF_CELL) {
        next_vobu = priv->cur_pack + (dsi_pack.vobu_sri.next_vobu & 0x7fffffff);
      } else {
        next_vobu = priv->cur_pack + cur_output_size + 1;
      }

      assert (cur_output_size < 1024);
      priv->cur_pack++;

            /**
             * Read in and output cursize packs.
             */
      len = DVDReadBlocks (priv->title, priv->cur_pack, cur_output_size, data);
      if (len != cur_output_size) {
        fprintf (stderr, "Read failed for %d blocks at %d\n",
            cur_output_size, priv->cur_pack);
        _close (priv);
        return -1;
      }

      GST_BUFFER_SIZE (buf) = cur_output_size * DVD_VIDEO_LB_LEN;
      priv->cur_pack = next_vobu;
    }
  } else {
    return -1;
  }

  return 0;
}

static GstData *
dvdreadsrc_get (GstPad * pad)
{
  DVDReadSrc *dvdreadsrc;
  DVDReadSrcPrivate *priv;
  GstBuffer *buf;

  g_return_val_if_fail (pad != NULL, NULL);
  g_return_val_if_fail (GST_IS_PAD (pad), NULL);

  dvdreadsrc = DVDREADSRC (gst_pad_get_parent (pad));
  priv = dvdreadsrc->priv;
  g_return_val_if_fail (GST_FLAG_IS_SET (dvdreadsrc, DVDREADSRC_OPEN), NULL);

  /* create the buffer */
  /* FIXME: should eventually use a bufferpool for this */
  buf = gst_buffer_new ();
  g_return_val_if_fail (buf, NULL);

  /* allocate the space for the buffer data */
  GST_BUFFER_DATA (buf) = g_malloc (1024 * DVD_VIDEO_LB_LEN);
  g_return_val_if_fail (GST_BUFFER_DATA (buf) != NULL, NULL);

  if (priv->new_seek) {
    _seek (priv, priv->titleid, priv->chapid, priv->angle);
  }

  /* read it in from the file */
  if (_read (priv, priv->angle, priv->new_seek, buf)) {
    gst_element_signal_eos (GST_ELEMENT (dvdreadsrc));
    return NULL;
  }

  if (priv->new_seek) {
    priv->new_seek = FALSE;
  }

  return buf;
}
#endif

/* open the file, necessary to go to RUNNING state */
static gboolean
dvdreadsrc_open_file (DVDReadSrc * src)
{
  g_return_val_if_fail (src != NULL, FALSE);
  g_return_val_if_fail (GST_IS_DVDREADSRC (src), FALSE);
  g_return_val_if_fail (!GST_FLAG_IS_SET (src, DVDREADSRC_OPEN), FALSE);

  if (_open (src->priv, src->priv->location))
    return FALSE;
  if (_seek (src->priv, src->priv->title, src->priv->chapter, src->priv->angle))
    return FALSE;

  GST_FLAG_SET (src, DVDREADSRC_OPEN);

  return TRUE;
}

/* close the file */
static void
dvdreadsrc_close_file (DVDReadSrc * src)
{
  g_return_if_fail (GST_FLAG_IS_SET (src, DVDREADSRC_OPEN));

  _close (src->priv);

  GST_FLAG_UNSET (src, DVDREADSRC_OPEN);
}

static GstElementStateReturn
dvdreadsrc_change_state (GstElement * element)
{
  g_return_val_if_fail (GST_IS_DVDREADSRC (element), GST_STATE_FAILURE);

  GST_DEBUG ("gstdvdreadsrc: state pending %d", GST_STATE_PENDING (element));

  /* if going down into NULL state, close the file if it's open */
  if (GST_STATE_PENDING (element) == GST_STATE_NULL) {
    if (GST_FLAG_IS_SET (element, DVDREADSRC_OPEN))
      dvdreadsrc_close_file (DVDREADSRC (element));
    /* otherwise (READY or higher) we need to open the file */
  } else {
    if (!GST_FLAG_IS_SET (element, DVDREADSRC_OPEN)) {
      if (!dvdreadsrc_open_file (DVDREADSRC (element)))
        return GST_STATE_FAILURE;
    }
  }

  /* if we haven't failed already, give the parent class a chance to ;-) */
  if (GST_ELEMENT_CLASS (parent_class)->change_state)
    return GST_ELEMENT_CLASS (parent_class)->change_state (element);

  return GST_STATE_SUCCESS;
}

static gboolean
plugin_init (GstPlugin * plugin)
{
  if (!gst_element_register (plugin, "dvdreadsrc", GST_RANK_NONE,
          GST_TYPE_DVDREADSRC))
    return FALSE;

  return TRUE;
}

GST_PLUGIN_DEFINE (GST_VERSION_MAJOR,
    GST_VERSION_MINOR,
    "dvdreadsrc",
    "Access a DVD with dvdread",
    plugin_init, VERSION, "GPL", GST_PACKAGE, GST_ORIGIN)