public static void OverwriteSequenceNumbers(File file,
long position,
IDictionary <uint, int> shiftTable)
{
bool done = true;
foreach (KeyValuePair <uint, int> pair in shiftTable)
{
if (pair.Value != 0)
{
done = false;
break;
}
}
if (done)
{
return;
}
while (position < file.Length)
{
PageHeader header = new PageHeader(file, position);
int size = (int)(header.Size + header.DataSize);
if (shiftTable.ContainsKey(header.StreamSerialNumber) &&
shiftTable [header.StreamSerialNumber] != 0)
{
file.Seek(position);
ByteVector page_data = file.ReadBlock(size);
ByteVector new_data = ByteVector.FromUInt(
(uint)(header.PageSequenceNumber +
shiftTable [header.StreamSerialNumber]),
false);
for (int i = 18; i < 22; i++)
{
page_data [i] = new_data [i - 18];
}
for (int i = 22; i < 26; i++)
{
page_data [i] = 0;
}
new_data.Add(ByteVector.FromUInt(
page_data.Checksum, false));
file.Seek(position + 18);
file.WriteBlock(new_data);
}
position += size;
}
}
/// <summary>
/// Constructs and initializes a new instance of <see
/// cref="Page" /> by reading a raw Ogg page from a specified
/// position in a specified file.
/// </summary>
/// <param name="file">
/// A <see cref="File" /> object containing the file from
/// which the contents of the new instance are to be read.
/// </param>
/// <param name="position">
/// A <see cref="long" /> value specify at what position to
/// read.
/// </param>
/// <exception cref="ArgumentNullException">
/// <paramref name="file" /> is <see langword="null" />.
/// </exception>
/// <exception cref="ArgumentOutOfRangeException">
/// <paramref name="position" /> is less than zero or greater
/// than the size of the file.
/// </exception>
/// <exception cref="CorruptFileException">
/// The Ogg identifier could not be found at the correct
/// location.
/// </exception>
public Page(File file, long position)
: this(new PageHeader (file, position))
{
file.Seek (position + header.Size);
foreach (int packet_size in header.PacketSizes)
packets.Add (file.ReadBlock (packet_size));
}
public PageHeader(File file, long position)
{
file.Seek(position);
// An Ogg page header is at least 27 bytes, so we'll go ahead and read that
// much and then get the rest when we're ready for it.
ByteVector data = file.ReadBlock(27);
if (data.Count < 27 || !data.StartsWith("OggS"))
{
throw new CorruptFileException("Error reading page header");
}
_version = data [4];
_flags = (PageFlags)data [5];
_absolute_granular_position = data.Mid(6, 8).ToULong(false);
_stream_serial_number = data.Mid(14, 4).ToUInt(false);
_page_sequence_number = data.Mid(18, 4).ToUInt(false);
// Byte number 27 is the number of page segments, which is the only variable
// length portion of the page header. After reading the number of page
// segments we'll then read in the coresponding data for this count.
int page_segment_count = data [26];
ByteVector page_segments = file.ReadBlock(page_segment_count);
// Another sanity check.
if (page_segment_count < 1 || page_segments.Count != page_segment_count)
{
throw new CorruptFileException("Incorrect number of page segments");
}
// The base size of an Ogg page 27 bytes plus the number of lacing values.
_size = (uint)(27 + page_segment_count);
_packet_sizes = new List <int> ();
int packet_size = 0;
_data_size = 0;
for (int i = 0; i < page_segment_count; i++)
{
_data_size += page_segments [i];
packet_size += page_segments [i];
if (page_segments [i] < 255)
{
_packet_sizes.Add(packet_size);
packet_size = 0;
}
}
if (packet_size > 0)
{
_packet_sizes.Add(packet_size);
}
}
public Page(File file, long position) :
this(new PageHeader(file, position))
{
file.Seek(position + header.Size);
foreach (int packet_size in header.PacketSizes)
{
packets.Add(file.ReadBlock(packet_size));
}
}
public Page (File file, long position) : this (new PageHeader (file, position))
{
if (file == null)
throw new ArgumentNullException ("file");
file.Seek (position + header.Size);
foreach (int packet_size in header.PacketSizes)
packets.Add (file.ReadBlock (packet_size));
}
public Page(File file, long position) : this(new PageHeader(file, position))
{
if (file == null)
{
throw new ArgumentNullException("file");
}
file.Seek(position + header.Size);
foreach (int packet_size in header.PacketSizes)
{
packets.Add(file.ReadBlock(packet_size));
}
}
public PageHeader(File file, long position)
{
if (file == null)
{
throw new ArgumentNullException("file");
}
if (position < 0 || position > file.Length - 27)
{
throw new ArgumentOutOfRangeException("position");
}
file.Seek(position);
ByteVector data = file.ReadBlock(27);
if (data.Count < 27 || !data.StartsWith("OggS"))
{
throw new CorruptFileException("Error reading page header");
}
version = data[4];
this.flags = (PageFlags)data[5];
absolute_granular_position = data.Mid(6, 8).ToULong(false);
stream_serial_number = data.Mid(14, 4).ToUInt(false);
page_sequence_number = data.Mid(18, 4).ToUInt(false);
int page_segment_count = data[26];
ByteVector page_segments = file.ReadBlock(page_segment_count);
if (page_segment_count < 1 || page_segments.Count != page_segment_count)
{
throw new CorruptFileException("Incorrect number of page segments");
}
size = (uint)(27 + page_segment_count);
packet_sizes = new List <int>();
int packet_size = 0;
data_size = 0;
for (int i = 0; i < page_segment_count; i++)
{
data_size += page_segments[i];
packet_size += page_segments[i];
if (page_segments[i] < 255)
{
packet_sizes.Add(packet_size);
packet_size = 0;
}
}
if (packet_size > 0)
{
packet_sizes.Add(packet_size);
}
}
public static void OverwriteSequenceNumbers (File file,
long position,
IDictionary<uint, int> shiftTable)
{
bool done = true;
foreach (KeyValuePair<uint, int> pair in shiftTable)
if (pair.Value != 0) {
done = false;
break;
}
if (done)
return;
while (position < file.Length) {
PageHeader header = new PageHeader (file, position);
int size = (int) (header.Size + header.DataSize);
if (shiftTable.ContainsKey (header.StreamSerialNumber)
&& shiftTable [header.StreamSerialNumber] != 0) {
file.Seek (position);
ByteVector page_data = file.ReadBlock (size);
ByteVector new_data = ByteVector.FromUInt (
(uint)(header.PageSequenceNumber +
shiftTable [header.StreamSerialNumber]),
false);
for (int i = 18; i < 22; i ++)
page_data [i] = new_data [i - 18];
for (int i = 22; i < 26; i++)
page_data [i] = 0;
new_data.Add (ByteVector.FromUInt (
page_data.Checksum, false));
file.Seek (position + 18);
file.WriteBlock (new_data);
}
position += size;
}
}
/// <summary>
/// Constructs and initializes a new instance of <see
/// cref="PageHeader" /> by reading a raw Ogg page header
/// from a specified position in a specified file.
/// </summary>
/// <param name="file">
/// A <see cref="File" /> object containing the file from
/// which the contents of the new instance are to be read.
/// </param>
/// <param name="position">
/// A <see cref="long" /> value specify at what position to
/// read.
/// </param>
/// <exception cref="ArgumentNullException">
/// <paramref name="file" /> is <see langword="null" />.
/// </exception>
/// <exception cref="ArgumentOutOfRangeException">
/// <paramref name="position" /> is less than zero or greater
/// than the size of the file.
/// </exception>
/// <exception cref="CorruptFileException">
/// The Ogg identifier could not be found at the correct
/// location.
/// </exception>
public PageHeader(File file, long position)
{
if (file == null)
throw new ArgumentNullException ("file");
if (position < 0 || position > file.Length - 27)
throw new ArgumentOutOfRangeException (
"position");
file.Seek (position);
// An Ogg page header is at least 27 bytes, so we'll go
// ahead and read that much and then get the rest when
// we're ready for it.
ByteVector data = file.ReadBlock (27);
if (data.Count < 27 || !data.StartsWith ("OggS"))
System.Console.WriteLine(
"Error reading page header");
version = data [4];
this.flags = (PageFlags) data [5];
absolute_granular_position = data.Mid(6, 8).ToULong (
false);
stream_serial_number = data.Mid(14, 4).ToUInt (false);
page_sequence_number = data.Mid(18, 4).ToUInt (false);
// Byte number 27 is the number of page segments, which
// is the only variable length portion of the page
// header. After reading the number of page segments
// we'll then read in the coresponding data for this
// count.
int page_segment_count = data [26];
ByteVector page_segments =
file.ReadBlock (page_segment_count);
// Another sanity check.
if (page_segment_count < 1 ||
page_segments.Count != page_segment_count)
System.Console.WriteLine(
"Incorrect number of page segments");
// The base size of an Ogg page 27 bytes plus the number
// of lacing values.
size = (uint)(27 + page_segment_count);
packet_sizes = new List<int> ();
int packet_size = 0;
data_size = 0;
for (int i = 0; i < page_segment_count; i++) {
data_size += page_segments [i];
packet_size += page_segments [i];
if (page_segments [i] < 255) {
packet_sizes.Add (packet_size);
packet_size = 0;
}
}
if (packet_size > 0)
packet_sizes.Add (packet_size);
}
/// <summary>
/// Constructs and initializes a new instance of <see
/// cref="PageHeader" /> by reading a raw Ogg page header
/// from a specified position in a specified file.
/// </summary>
/// <param name="file">
/// A <see cref="File" /> object containing the file from
/// which the contents of the new instance are to be read.
/// </param>
/// <param name="position">
/// A <see cref="long" /> value specify at what position to
/// read.
/// </param>
/// <exception cref="ArgumentNullException">
/// <paramref name="file" /> is <see langword="null" />.
/// </exception>
/// <exception cref="ArgumentOutOfRangeException">
/// <paramref name="position" /> is less than zero or greater
/// than the size of the file.
/// </exception>
/// <exception cref="CorruptFileException">
/// The Ogg identifier could not be found at the correct
/// location.
/// </exception>
public PageHeader(File file, long position)
{
if (file == null)
{
throw new ArgumentNullException(nameof(file));
}
if (position < 0 || position > file.Length - 27)
{
throw new ArgumentOutOfRangeException(nameof(position));
}
file.Seek(position);
// An Ogg page header is at least 27 bytes, so we'll go
// ahead and read that much and then get the rest when
// we're ready for it.
ByteVector data = file.ReadBlock(27);
if (data.Count < 27 || !data.StartsWith("OggS"))
{
throw new CorruptFileException("Error reading page header");
}
version = data[4];
Flags = (PageFlags)data[5];
absolute_granular_position = data.Mid(6, 8).ToULong(false);
StreamSerialNumber = data.Mid(14, 4).ToUInt(false);
PageSequenceNumber = data.Mid(18, 4).ToUInt(false);
// Byte number 27 is the number of page segments, which
// is the only variable length portion of the page
// header. After reading the number of page segments
// we'll then read in the coresponding data for this
// count.
int page_segment_count = data[26];
ByteVector page_segments = file.ReadBlock(page_segment_count);
// Another sanity check.
if (page_segment_count < 1 || page_segments.Count != page_segment_count)
{
throw new CorruptFileException("Incorrect number of page segments");
}
// The base size of an Ogg page 27 bytes plus the number
// of lacing values.
Size = (uint)(27 + page_segment_count);
packet_sizes = new List <int> ();
int packet_size = 0;
DataSize = 0;
for (int i = 0; i < page_segment_count; i++)
{
DataSize += page_segments[i];
packet_size += page_segments[i];
if (page_segments[i] < 255)
{
packet_sizes.Add(packet_size);
packet_size = 0;
}
}
if (packet_size > 0)
{
packet_sizes.Add(packet_size);
}
}
/// <summary>
/// Overwrites all page headers in a file starting at a
/// specified position, shifting the page sequence numbers
/// a set amount.
/// </summary>
/// <param name="file">
/// A <see cref="File" /> object containing the file to
/// update.
/// </param>
/// <param name="position">
/// A <see cref="long" /> value specify at what position to
/// start updating.
/// </param>
/// <param name="shiftTable">
/// A <see cref="T:System.Collections.Generic.IDictionary`2"
/// /> object where the key is the serial number of the
/// stream to update and the value is the amount to offset
/// the page sequence numbers in the stream.
/// </param>
/// <exception cref="ArgumentNullException">
/// <paramref name="file" /> or <paramref name="shiftTable"
/// /> is <see langword="null" />.
/// </exception>
/// <remarks>
/// When the number of pages in a stream changes, all
/// subsequent pages in the stream need to have their page
/// sequence number update in order to remain valid.
/// Additionally, when the page sequence number changes, the
/// page needs to have its checksum recomputed. This makes
/// for a costly recalculation if large comment data is
/// added.
/// </remarks>
public static void OverwriteSequenceNumbers(File file,
long position,
IDictionary <uint, int> shiftTable)
{
if (file == null)
{
throw new ArgumentNullException("file");
}
if (shiftTable == null)
{
throw new ArgumentNullException("shiftTable");
}
// Check to see if there are no changes to be made.
bool done = true;
foreach (KeyValuePair <uint, int> pair in shiftTable)
{
if (pair.Value != 0)
{
done = false;
break;
}
}
// If the file is fine, quit.
if (done)
{
return;
}
while (position < file.Length - 27)
{
PageHeader header = new PageHeader(file, position);
int size = (int)(header.Size + header.DataSize);
if (shiftTable.ContainsKey(header.StreamSerialNumber) &&
shiftTable [header.StreamSerialNumber] != 0)
{
file.Seek(position);
ByteVector page_data = file.ReadBlock(size);
ByteVector new_data = ByteVector.FromUInt(
(uint)(header.PageSequenceNumber +
shiftTable [header.StreamSerialNumber]),
false);
for (int i = 18; i < 22; i++)
{
page_data [i] = new_data [i - 18];
}
for (int i = 22; i < 26; i++)
{
page_data [i] = 0;
}
new_data.Add(ByteVector.FromUInt(
page_data.Checksum, false));
file.Seek(position + 18);
file.WriteBlock(new_data);
}
position += size;
}
}
/// <summary>
/// Overwrites all page headers in a file starting at a
/// specified position, shifting the page sequence numbers
/// a set amount.
/// </summary>
/// <param name="file">
/// A <see cref="File" /> object containing the file to
/// update.
/// </param>
/// <param name="position">
/// A <see cref="long" /> value specify at what position to
/// start updating.
/// </param>
/// <param name="shiftTable">
/// A <see cref="T:System.Collections.Generic.IDictionary`2"
/// /> object where the key is the serial number of the
/// stream to update and the value is the amount to offset
/// the page sequence numbers in the stream.
/// </param>
/// <exception cref="ArgumentNullException">
/// <paramref name="file" /> or <paramref name="shiftTable"
/// /> is <see langword="null" />.
/// </exception>
/// <remarks>
/// When the number of pages in a stream changes, all
/// subsequent pages in the stream need to have their page
/// sequence number update in order to remain valid.
/// Additionally, when the page sequence number changes, the
/// page needs to have its checksum recomputed. This makes
/// for a costly recalculation if large comment data is
/// added.
/// </remarks>
public static void OverwriteSequenceNumbers (File file,
long position,
IDictionary<uint, int> shiftTable)
{
if (file == null)
throw new ArgumentNullException ("file");
if (shiftTable == null)
throw new ArgumentNullException ("shiftTable");
// Check to see if there are no changes to be made.
bool done = true;
foreach (KeyValuePair<uint, int> pair in shiftTable)
if (pair.Value != 0) {
done = false;
break;
}
// If the file is fine, quit.
if (done)
return;
while (position < file.Length - 27) {
PageHeader header = new PageHeader (file, position);
int size = (int) (header.Size + header.DataSize);
if (shiftTable.ContainsKey (header.StreamSerialNumber)
&& shiftTable [header.StreamSerialNumber] != 0) {
file.Seek (position);
ByteVector page_data = file.ReadBlock (size);
ByteVector new_data = ByteVector.FromUInt (
(uint)(header.PageSequenceNumber +
shiftTable [header.StreamSerialNumber]),
false);
for (int i = 18; i < 22; i ++)
page_data [i] = new_data [i - 18];
for (int i = 22; i < 26; i++)
page_data [i] = 0;
new_data.Add (ByteVector.FromUInt (
page_data.Checksum, false));
file.Seek (position + 18);
file.WriteBlock (new_data);
}
position += size;
}
}
