/* GStreamer EBML I/O

 * (c) 2003 Ronald Bultje <rbultje@ronald.bitfreak.net>

 *

 * ebml-read.c: read EBML data from file/stream

 *

 * 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., 51 Franklin St, Fifth Floor,

 * Boston, MA 02110-1301, USA.

 */

#ifndef __GST_EBML_READ_H__

#define __GST_EBML_READ_H__

#include <gst/gst.h>

#include <gst/base/gstbytereader.h>

G_BEGIN_DECLS

#define GST_TYPE_EBML_READ \

  (gst_ebml_read_get_type ())

#define GST_EBML_READ(obj) \

  (G_TYPE_CHECK_INSTANCE_CAST ((obj), GST_TYPE_EBML_READ, GstEbmlRead))

#define GST_EBML_READ_CLASS(klass) \

  (G_TYPE_CHECK_CLASS_CAST ((klass), GST_TYPE_EBML_READ, GstEbmlReadClass))

#define GST_IS_EBML_READ(obj) \

  (G_TYPE_CHECK_INSTANCE_TYPE ((obj), GST_TYPE_EBML_READ))

#define GST_IS_EBML_READ_CLASS(klass) \

  (G_TYPE_CHECK_CLASS_TYPE ((klass), GST_TYPE_EBML_READ))

#define GST_EBML_READ_GET_CLASS(obj) \

  (G_TYPE_INSTANCE_GET_CLASS ((obj), GST_TYPE_EBML_READ, GstEbmlReadClass))

GST_DEBUG_CATEGORY_EXTERN (ebmlread_debug);

/* custom flow return code */

#define  GST_FLOW_PARSE  GST_FLOW_CUSTOM_ERROR

typedef struct _GstEbmlMaster {

  guint64       offset;

  GstByteReader br;

} GstEbmlMaster;

typedef struct _GstEbmlRead {

  GstElement *el;

  GstBuffer *buf;

  guint64 offset;

  GstMapInfo map;

  GArray *readers;

} GstEbmlRead;

typedef GstFlowReturn (*GstPeekData) (gpointer * context, guint peek, const guint8 ** data);

/* returns UNEXPECTED if not enough data */

GstFlowReturn gst_ebml_peek_id_length    (guint32 * _id, guint64 * _length,

                                          guint * _needed,

                                          GstPeekData peek, gpointer * ctx,

                                          GstElement * el, guint64 offset);

void          gst_ebml_read_init         (GstEbmlRead * ebml,

                                          GstElement * el, GstBuffer * buf,

                                          guint64 offset);

void          gst_ebml_read_clear        (GstEbmlRead * ebml);

GstFlowReturn gst_ebml_peek_id           (GstEbmlRead * ebml, guint32 * id);

/* return _PARSE if not enough data to read what is needed, _ERROR or _OK */

GstFlowReturn gst_ebml_read_skip         (GstEbmlRead *ebml);

GstFlowReturn gst_ebml_read_buffer       (GstEbmlRead *ebml,

                                          guint32     *id,

                                          GstBuffer  **buf);

GstFlowReturn gst_ebml_read_uint         (GstEbmlRead *ebml,

                                          guint32     *id,

                                          guint64     *num);

GstFlowReturn gst_ebml_read_sint         (GstEbmlRead *ebml,

                                          guint32     *id,

                                          gint64      *num);

GstFlowReturn gst_ebml_read_float        (GstEbmlRead *ebml,

                                          guint32     *id,

                                          gdouble     *num);

GstFlowReturn gst_ebml_read_ascii        (GstEbmlRead *ebml,

                                          guint32     *id,

                                          gchar      **str);

GstFlowReturn gst_ebml_read_utf8         (GstEbmlRead *ebml,

                                          guint32     *id,

                                          gchar      **str);

GstFlowReturn gst_ebml_read_date         (GstEbmlRead *ebml,

                                          guint32     *id,

                                          gint64      *date);

GstFlowReturn gst_ebml_read_master       (GstEbmlRead *ebml,

                                          guint32     *id);

GstFlowReturn gst_ebml_read_pop_master   (GstEbmlRead *ebml);

GstFlowReturn gst_ebml_read_binary       (GstEbmlRead *ebml,

                                          guint32     *id,

                                          guint8     **binary,

                                          guint64     *length);

GstFlowReturn gst_ebml_read_header       (GstEbmlRead *read,

                                          gchar      **doctype,

                                          guint       *version);

/* Returns current (absolute) position of Ebml parser,

 * i.e. taking into account offset provided at init */

static inline guint64

gst_ebml_read_get_pos (GstEbmlRead * ebml)

{

  GstEbmlMaster *m;

  g_return_val_if_fail (ebml->readers, 0);

  g_return_val_if_fail (ebml->readers->len, 0);

  m = &(g_array_index (ebml->readers, GstEbmlMaster, ebml->readers->len - 1));

  return m->offset + gst_byte_reader_get_pos (&m->br);

}

/* Returns starting offset of Ebml parser */

static inline guint64

gst_ebml_read_get_offset (GstEbmlRead * ebml)

{

  return ebml->offset;

}

static inline GstByteReader *

gst_ebml_read_br (GstEbmlRead * ebml)

{

  g_return_val_if_fail (ebml->readers, NULL);

  g_return_val_if_fail (ebml->readers->len, NULL);

  return &(g_array_index (ebml->readers,

          GstEbmlMaster, ebml->readers->len - 1).br);

}

static inline gboolean

gst_ebml_read_has_remaining (GstEbmlRead * ebml, guint64 bytes_needed,

    gboolean auto_pop)

{

  gboolean res;

  res = (gst_byte_reader_get_remaining (gst_ebml_read_br (ebml)) >= bytes_needed);

  if (G_LIKELY (!res && auto_pop)) {

    gst_ebml_read_pop_master (ebml);

  }

  return G_LIKELY (res);

}

G_END_DECLS

#endif /* __GST_EBML_READ_H__ */