/* * The contents of this file are subject to the Mozilla Public License * Version 1.1 (the "License"); you may not use this file except in * compliance with the License. You may obtain a copy of the License at * http://www.mozilla.org/MPL/. * * Software distributed under the License is distributed on an "AS IS" * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See the * License for the specific language governing rights and limitations * under the License. * * The Original Code is Fluendo MPEG Demuxer plugin. * * The Initial Developer of the Original Code is Fluendo, S.L. * Portions created by Fluendo, S.L. are Copyright (C) 2005 * Fluendo, S.L. All Rights Reserved. * * Contributor(s): Wim Taymans <wim@fluendo.com> * Jan Schmidt <thaytan@noraisin.net> */ #include <string.h> #include <gst/gst.h> #include "gstmpegdesc.h" void gst_mpeg_descriptor_free (GstMPEGDescriptor * desc) { g_return_if_fail (desc != NULL); g_free (desc); } static guint gst_mpeg_descriptor_parse_1 (guint8 * data, guint size) { guint8 tag; guint8 length; /* need at least 2 bytes for tag and length */ if (size < 2) return 0; tag = *data++; length = *data++; size -= 2; GST_DEBUG ("tag: 0x%02x, length: %d", tag, length); if (length > size) return 0; return length + 2;; } GstMPEGDescriptor * gst_mpeg_descriptor_parse (guint8 * data, guint size) { guint8 *current; guint consumed, total, n_desc; GstMPEGDescriptor *result; g_return_val_if_fail (data != NULL, NULL); current = data; total = 0; n_desc = 0; do { consumed = gst_mpeg_descriptor_parse_1 (current, size); if (consumed > 0) { current += consumed; total += consumed; size -= consumed; n_desc++; } } while (consumed > 0); GST_DEBUG ("parsed %d descriptors", n_desc); if (total == 0) return NULL; result = g_malloc (sizeof (GstMPEGDescriptor) + total); result->n_desc = n_desc; result->data_length = total; result->data = ((guint8 *) result) + sizeof (GstMPEGDescriptor); memcpy (result->data, data, total); return result; } guint gst_mpeg_descriptor_n_desc (GstMPEGDescriptor * desc) { g_return_val_if_fail (desc != NULL, 0); return desc->n_desc; } guint8 * gst_mpeg_descriptor_find (GstMPEGDescriptor * desc, gint tag) { gint length; guint8 *current; guint size; g_return_val_if_fail (desc != NULL, NULL); current = desc->data; length = desc->data_length; while (length > 0) { if (DESC_TAG (current) == tag) return current; size = DESC_LENGTH (current) + 2; current += size; length -= size; } return NULL; } guint8 * gst_mpeg_descriptor_nth (GstMPEGDescriptor * desc, guint i) { gint length; guint8 *current; guint size; g_return_val_if_fail (desc != NULL, NULL); if (i > desc->n_desc) return NULL; current = desc->data; length = desc->data_length; while (length > 0) { if (i == 0) return current; size = DESC_LENGTH (current) + 2; current += size; length -= size; i--; } return NULL; }