Exemplo n.º 1
0
        /// <summary>
        ///    Populates the current instance with the contents of the
        ///    raw ID3v2 frame.
        /// </summary>
        /// <param name="data">
        ///    A <see cref="ByteVector" /> object containing the raw
        ///    extended header structure.
        /// </param>
        /// <param name="version">
        ///    A <see cref="byte" /> value indicating the ID3v2 version.
        /// </param>
        protected void Parse(ByteVector data, byte version)
        {
            if (data == null)
            {
                throw new ArgumentNullException("data");
            }

            size = (version == 3 ? 4u : 0u) + SynchData.ToUInt(data.Mid(0, 4));
        }
Exemplo n.º 2
0
        /// <summary>
        ///    Constructs and initializes a new instance of <see
        ///    cref="Header" /> by reading it from raw header data.
        /// </summary>
        /// <param name="data">
        ///    A <see cref="ByteVector" /> object containing the raw
        ///    data to build the new instance from.
        /// </param>
        /// <exception cref="ArgumentNullException">
        ///    <paramref name="data" /> is <see langword="null" />.
        /// </exception>
        /// <exception cref="CorruptFileException">
        ///    <paramref name="data" /> is smaller than <see
        ///    cref="Size" />, does not begin with <see
        ///    cref="FileIdentifier" />, contains invalid flag data,
        ///    or contains invalid size data.
        /// </exception>
        public Header(ByteVector data)
        {
            if (data == null)
            {
                throw new ArgumentNullException("data");
            }

            if (data.Count < Size)
            {
                throw new CorruptFileException(
                          "Provided data is smaller than object size.");
            }

            if (!data.StartsWith(FileIdentifier))
            {
                throw new CorruptFileException(
                          "Provided data does not start with the file identifier");
            }

            major_version   = data [3];
            revision_number = data [4];
            flags           = (HeaderFlags)data [5];

            if (major_version == 2 && ((int)flags & 127) != 0)
            {
                throw new CorruptFileException(
                          "Invalid flags set on version 2 tag.");
            }

            if (major_version == 3 && ((int)flags & 15) != 0)
            {
                throw new CorruptFileException(
                          "Invalid flags set on version 3 tag.");
            }

            if (major_version == 4 && ((int)flags & 7) != 0)
            {
                throw new CorruptFileException(
                          "Invalid flags set on version 4 tag.");
            }

            for (int i = 6; i < 10; i++)
            {
                if (data [i] >= 128)
                {
                    throw new CorruptFileException(
                              "One of the bytes in the header was greater than the allowed 128.");
                }
            }

            tag_size = SynchData.ToUInt(data.Mid(6, 4));
        }
Exemplo n.º 3
0
        /// <summary>
        ///    Constructs and initializes a new instance of <see
        ///    cref="FrameHeader" /> by reading it from raw header data
        ///    of a specified version.
        /// </summary>
        /// <param name="data">
        ///    A <see cref="ByteVector" /> object containing the raw
        ///    data to build the new instance from.
        /// </param>
        /// <param name="version">
        ///    A <see cref="byte" /> value containing the ID3v2 version
        ///    with which the data in <paramref name="data" /> was
        ///    encoded.
        /// </param>
        /// <remarks>
        ///    If the data size is smaller than the size of a full
        ///    header, the data is just treated as a frame identifier
        ///    and the remaining values are zeroed.
        /// </remarks>
        /// <exception cref="ArgumentNullException">
        ///    <paramref name="data" /> is <see langword="null" />.
        /// </exception>
        /// <exception cref="CorruptFileException">
        ///    <paramref name="data" /> is smaller than the size of a
        ///    frame identifier or <paramref name="version" /> is less
        ///    than 2 or more than 4.
        /// </exception>
        public FrameHeader(ByteVector data, byte version)
        {
            if (data == null)
            {
                throw new ArgumentNullException("data");
            }

            flags      = 0;
            frame_size = 0;

            if (version < 2 || version > 4)
            {
                throw new CorruptFileException(
                          "Unsupported tag version.");
            }

            if (data.Count < (version == 2 ? 3 : 4))
            {
                throw new CorruptFileException(
                          "Data must contain at least a frame ID.");
            }

            switch (version)
            {
            case 2:
                // Set the frame ID -- the first three bytes
                frame_id = ConvertId(data.Mid(0, 3), version,
                                     false);

                // If the full header information was not passed
                // in, do not continue to the steps to parse the
                // frame size and flags.
                if (data.Count < 6)
                {
                    return;
                }

                frame_size = data.Mid(3, 3).ToUInt();
                return;

            case 3:
                // Set the frame ID -- the first four bytes
                frame_id = ConvertId(data.Mid(0, 4), version,
                                     false);

                // If the full header information was not passed
                // in, do not continue to the steps to parse the
                // frame size and flags.
                if (data.Count < 10)
                {
                    return;
                }

                // Store the flags internally as version 2.4.
                frame_size = data.Mid(4, 4).ToUInt();
                flags      = (FrameFlags)(
                    ((data [8] << 7) & 0x7000) |
                    ((data [9] >> 4) & 0x000C) |
                    ((data [9] << 1) & 0x0040));

                return;

            case 4:
                // Set the frame ID -- the first four bytes
                frame_id = new ReadOnlyByteVector(
                    data.Mid(0, 4));

                // If the full header information was not passed
                // in, do not continue to the steps to parse the
                // frame size and flags.
                if (data.Count < 10)
                {
                    return;
                }

                frame_size = SynchData.ToUInt(data.Mid(4, 4));
                flags      = (FrameFlags)data.Mid(8, 2).ToUShort();

                return;

            default:
                throw new CorruptFileException(
                          "Unsupported tag version.");
            }
        }