gstreamer/gst/isomp4/qtdemux_tree.c

/* GStreamer
 * Copyright (C) <1999> Erik Walthinsen <omega@cse.ogi.edu>
 * Copyright (C) <2003> David A. Schleef <ds@schleef.org>
 * Copyright (C) <2006> Wim Taymans <wim@fluendo.com>
 * Copyright (C) <2007> Julien Moutte <julien@fluendo.com>
 * Copyright (C) <2009> Tim-Philipp Müller <tim centricular net>
 * Copyright (C) <2009> STEricsson <benjamin.gaignard@stericsson.com>
 * Copyright (C) <2013> Sreerenj Balachandran <sreerenj.balachandran@intel.com>
 * Copyright (C) <2013> Intel Corporation
 * Copyright (C) <2014> Centricular Ltd
 * Copyright (C) <2015> YouView TV Ltd.
 * Copyright (C) <2016> British Broadcasting Corporation
 *
 * 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.
 */

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

#include "qtdemux_tree.h"
#include "qtdemux_types.h"
#include "fourcc.h"

GNode *
qtdemux_tree_get_child_by_type (GNode * node, guint32 fourcc)
{
  GNode *child;
  guint8 *buffer;
  guint32 child_fourcc;

  for (child = g_node_first_child (node); child;
      child = g_node_next_sibling (child)) {
    buffer = (guint8 *) child->data;

    child_fourcc = QT_FOURCC (buffer + 4);

    if (G_UNLIKELY (child_fourcc == fourcc)) {
      return child;
    }
  }
  return NULL;
}

GNode *
qtdemux_tree_get_child_by_type_full (GNode * node, guint32 fourcc,
    GstByteReader * parser)
{
  GNode *child;
  guint8 *buffer;
  guint32 child_fourcc, child_len;

  for (child = g_node_first_child (node); child;
      child = g_node_next_sibling (child)) {
    buffer = (guint8 *) child->data;

    child_len = QT_UINT32 (buffer);
    child_fourcc = QT_FOURCC (buffer + 4);

    if (G_UNLIKELY (child_fourcc == fourcc)) {
      if (G_UNLIKELY (child_len < (4 + 4)))
        return NULL;
      /* FIXME: must verify if atom length < parent atom length */
      gst_byte_reader_init (parser, buffer + (4 + 4), child_len - (4 + 4));
      return child;
    }
  }
  return NULL;
}

GNode *
qtdemux_tree_get_child_by_index (GNode * node, guint index)
{
  return g_node_nth_child (node, index);
}

GNode *
qtdemux_tree_get_sibling_by_type_full (GNode * node, guint32 fourcc,
    GstByteReader * parser)
{
  GNode *child;
  guint8 *buffer;
  guint32 child_fourcc, child_len;

  for (child = g_node_next_sibling (node); child;
      child = g_node_next_sibling (child)) {
    buffer = (guint8 *) child->data;

    child_fourcc = QT_FOURCC (buffer + 4);

    if (child_fourcc == fourcc) {
      if (parser) {
        child_len = QT_UINT32 (buffer);
        if (G_UNLIKELY (child_len < (4 + 4)))
          return NULL;
        /* FIXME: must verify if atom length < parent atom length */
        gst_byte_reader_init (parser, buffer + (4 + 4), child_len - (4 + 4));
      }
      return child;
    }
  }
  return NULL;
}

GNode *
qtdemux_tree_get_sibling_by_type (GNode * node, guint32 fourcc)
{
  return qtdemux_tree_get_sibling_by_type_full (node, fourcc, NULL);
}