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TarInputStream.cs
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TarInputStream.cs
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using System;
using System.Buffers;
using System.IO;
using System.Text;
using System.Threading;
using System.Threading.Tasks;
using ICSharpCode.SharpZipLib.Core;
namespace ICSharpCode.SharpZipLib.Tar
{
/// <summary>
/// The TarInputStream reads a UNIX tar archive as an InputStream.
/// methods are provided to position at each successive entry in
/// the archive, and the read each entry as a normal input stream
/// using read().
/// </summary>
public class TarInputStream : Stream
{
#region Constructors
/// <summary>
/// Construct a TarInputStream with default block factor
/// </summary>
/// <param name="inputStream">stream to source data from</param>
[Obsolete("No Encoding for Name field is specified, any non-ASCII bytes will be discarded")]
public TarInputStream(Stream inputStream)
: this(inputStream, TarBuffer.DefaultBlockFactor, null)
{
}
/// <summary>
/// Construct a TarInputStream with default block factor
/// </summary>
/// <param name="inputStream">stream to source data from</param>
/// <param name="nameEncoding">The <see cref="Encoding"/> used for the Name fields, or null for ASCII only</param>
public TarInputStream(Stream inputStream, Encoding nameEncoding)
: this(inputStream, TarBuffer.DefaultBlockFactor, nameEncoding)
{
}
/// <summary>
/// Construct a TarInputStream with user specified block factor
/// </summary>
/// <param name="inputStream">stream to source data from</param>
/// <param name="blockFactor">block factor to apply to archive</param>
[Obsolete("No Encoding for Name field is specified, any non-ASCII bytes will be discarded")]
public TarInputStream(Stream inputStream, int blockFactor)
{
this.inputStream = inputStream;
tarBuffer = TarBuffer.CreateInputTarBuffer(inputStream, blockFactor);
encoding = null;
}
/// <summary>
/// Construct a TarInputStream with user specified block factor
/// </summary>
/// <param name="inputStream">stream to source data from</param>
/// <param name="blockFactor">block factor to apply to archive</param>
/// <param name="nameEncoding">The <see cref="Encoding"/> used for the Name fields, or null for ASCII only</param>
public TarInputStream(Stream inputStream, int blockFactor, Encoding nameEncoding)
{
this.inputStream = inputStream;
tarBuffer = TarBuffer.CreateInputTarBuffer(inputStream, blockFactor);
encoding = nameEncoding;
}
#endregion Constructors
/// <summary>
/// Gets or sets a flag indicating ownership of underlying stream.
/// When the flag is true <see cref="Stream.Dispose()" /> will close the underlying stream also.
/// </summary>
/// <remarks>The default value is true.</remarks>
public bool IsStreamOwner
{
get { return tarBuffer.IsStreamOwner; }
set { tarBuffer.IsStreamOwner = value; }
}
#region Stream Overrides
/// <summary>
/// Gets a value indicating whether the current stream supports reading
/// </summary>
public override bool CanRead
{
get { return inputStream.CanRead; }
}
/// <summary>
/// Gets a value indicating whether the current stream supports seeking
/// This property always returns false.
/// </summary>
public override bool CanSeek
{
get { return false; }
}
/// <summary>
/// Gets a value indicating if the stream supports writing.
/// This property always returns false.
/// </summary>
public override bool CanWrite
{
get { return false; }
}
/// <summary>
/// The length in bytes of the stream
/// </summary>
public override long Length
{
get { return inputStream.Length; }
}
/// <summary>
/// Gets or sets the position within the stream.
/// Setting the Position is not supported and throws a NotSupportedExceptionNotSupportedException
/// </summary>
/// <exception cref="NotSupportedException">Any attempt to set position</exception>
public override long Position
{
get { return inputStream.Position; }
set { throw new NotSupportedException("TarInputStream Seek not supported"); }
}
/// <summary>
/// Flushes the baseInputStream
/// </summary>
public override void Flush()
{
inputStream.Flush();
}
/// <summary>
/// Flushes the baseInputStream
/// </summary>
/// <param name="cancellationToken"></param>
public override async Task FlushAsync(CancellationToken cancellationToken)
{
await inputStream.FlushAsync(cancellationToken).ConfigureAwait(false);
}
/// <summary>
/// Set the streams position. This operation is not supported and will throw a NotSupportedException
/// </summary>
/// <param name="offset">The offset relative to the origin to seek to.</param>
/// <param name="origin">The <see cref="SeekOrigin"/> to start seeking from.</param>
/// <returns>The new position in the stream.</returns>
/// <exception cref="NotSupportedException">Any access</exception>
public override long Seek(long offset, SeekOrigin origin)
{
throw new NotSupportedException("TarInputStream Seek not supported");
}
/// <summary>
/// Sets the length of the stream
/// This operation is not supported and will throw a NotSupportedException
/// </summary>
/// <param name="value">The new stream length.</param>
/// <exception cref="NotSupportedException">Any access</exception>
public override void SetLength(long value)
{
throw new NotSupportedException("TarInputStream SetLength not supported");
}
/// <summary>
/// Writes a block of bytes to this stream using data from a buffer.
/// This operation is not supported and will throw a NotSupportedException
/// </summary>
/// <param name="buffer">The buffer containing bytes to write.</param>
/// <param name="offset">The offset in the buffer of the frist byte to write.</param>
/// <param name="count">The number of bytes to write.</param>
/// <exception cref="NotSupportedException">Any access</exception>
public override void Write(byte[] buffer, int offset, int count)
{
throw new NotSupportedException("TarInputStream Write not supported");
}
/// <summary>
/// Writes a byte to the current position in the file stream.
/// This operation is not supported and will throw a NotSupportedException
/// </summary>
/// <param name="value">The byte value to write.</param>
/// <exception cref="NotSupportedException">Any access</exception>
public override void WriteByte(byte value)
{
throw new NotSupportedException("TarInputStream WriteByte not supported");
}
/// <summary>
/// Reads a byte from the current tar archive entry.
/// </summary>
/// <returns>A byte cast to an int; -1 if the at the end of the stream.</returns>
public override int ReadByte()
{
var oneByteBuffer = ArrayPool<byte>.Shared.Rent(1);
var num = Read(oneByteBuffer, 0, 1);
if (num <= 0)
{
// return -1 to indicate that no byte was read.
return -1;
}
var result = oneByteBuffer[0];
ArrayPool<byte>.Shared.Return(oneByteBuffer);
return result;
}
/// <summary>
/// Reads bytes from the current tar archive entry.
///
/// This method is aware of the boundaries of the current
/// entry in the archive and will deal with them appropriately
/// </summary>
/// <param name="buffer">
/// The buffer into which to place bytes read.
/// </param>
/// <param name="offset">
/// The offset at which to place bytes read.
/// </param>
/// <param name="count">
/// The number of bytes to read.
/// </param>
/// <param name="cancellationToken"></param>
/// <returns>
/// The number of bytes read, or 0 at end of stream/EOF.
/// </returns>
public override Task<int> ReadAsync(byte[] buffer, int offset, int count, CancellationToken cancellationToken)
{
return ReadAsync(buffer.AsMemory().Slice(offset, count), cancellationToken, true).AsTask();
}
#if NETSTANDARD2_1_OR_GREATER
/// <summary>
/// Reads bytes from the current tar archive entry.
///
/// This method is aware of the boundaries of the current
/// entry in the archive and will deal with them appropriately
/// </summary>
/// <param name="buffer">
/// The buffer into which to place bytes read.
/// </param>
/// <param name="cancellationToken"></param>
/// <returns>
/// The number of bytes read, or 0 at end of stream/EOF.
/// </returns>
public override ValueTask<int> ReadAsync(Memory<byte> buffer, CancellationToken cancellationToken =
new CancellationToken())
{
return ReadAsync(buffer, cancellationToken, true);
}
#endif
/// <summary>
/// Reads bytes from the current tar archive entry.
///
/// This method is aware of the boundaries of the current
/// entry in the archive and will deal with them appropriately
/// </summary>
/// <param name="buffer">
/// The buffer into which to place bytes read.
/// </param>
/// <param name="offset">
/// The offset at which to place bytes read.
/// </param>
/// <param name="count">
/// The number of bytes to read.
/// </param>
/// <returns>
/// The number of bytes read, or 0 at end of stream/EOF.
/// </returns>
public override int Read(byte[] buffer, int offset, int count)
{
if (buffer == null)
{
throw new ArgumentNullException(nameof(buffer));
}
return ReadAsync(buffer.AsMemory().Slice(offset, count), CancellationToken.None, false).GetAwaiter()
.GetResult();
}
private async ValueTask<int> ReadAsync(Memory<byte> buffer, CancellationToken ct, bool isAsync)
{
int offset = 0;
int totalRead = 0;
if (entryOffset >= entrySize)
{
return 0;
}
long numToRead = buffer.Length;
if ((numToRead + entryOffset) > entrySize)
{
numToRead = entrySize - entryOffset;
}
if (readBuffer != null)
{
int sz = (numToRead > readBuffer.Memory.Length) ? readBuffer.Memory.Length : (int)numToRead;
readBuffer.Memory.Slice(0, sz).CopyTo(buffer.Slice(offset, sz));
if (sz >= readBuffer.Memory.Length)
{
readBuffer.Dispose();
readBuffer = null;
}
else
{
int newLen = readBuffer.Memory.Length - sz;
var newBuf = ExactMemoryPool<byte>.Shared.Rent(newLen);
readBuffer.Memory.Slice(sz, newLen).CopyTo(newBuf.Memory);
readBuffer.Dispose();
readBuffer = newBuf;
}
totalRead += sz;
numToRead -= sz;
offset += sz;
}
var recLen = TarBuffer.BlockSize;
var recBuf = ArrayPool<byte>.Shared.Rent(recLen);
while (numToRead > 0)
{
await tarBuffer.ReadBlockIntAsync(recBuf, ct, isAsync).ConfigureAwait(false);
var sz = (int)numToRead;
if (recLen > sz)
{
recBuf.AsSpan().Slice(0, sz).CopyTo(buffer.Slice(offset, sz).Span);
readBuffer?.Dispose();
readBuffer = ExactMemoryPool<byte>.Shared.Rent(recLen - sz);
recBuf.AsSpan().Slice(sz, recLen - sz).CopyTo(readBuffer.Memory.Span);
}
else
{
sz = recLen;
recBuf.AsSpan().CopyTo(buffer.Slice(offset, recLen).Span);
}
totalRead += sz;
numToRead -= sz;
offset += sz;
}
ArrayPool<byte>.Shared.Return(recBuf);
entryOffset += totalRead;
return totalRead;
}
/// <summary>
/// Closes this stream. Calls the TarBuffer's close() method.
/// The underlying stream is closed by the TarBuffer.
/// </summary>
protected override void Dispose(bool disposing)
{
if (disposing)
{
tarBuffer.Close();
}
}
#if NETSTANDARD2_1_OR_GREATER
/// <summary>
/// Closes this stream. Calls the TarBuffer's close() method.
/// The underlying stream is closed by the TarBuffer.
/// </summary>
public override async ValueTask DisposeAsync()
{
await tarBuffer.CloseAsync(CancellationToken.None).ConfigureAwait(false);
}
#endif
#endregion Stream Overrides
/// <summary>
/// Set the entry factory for this instance.
/// </summary>
/// <param name="factory">The factory for creating new entries</param>
public void SetEntryFactory(IEntryFactory factory)
{
entryFactory = factory;
}
/// <summary>
/// Get the record size being used by this stream's TarBuffer.
/// </summary>
public int RecordSize
{
get { return tarBuffer.RecordSize; }
}
/// <summary>
/// Get the record size being used by this stream's TarBuffer.
/// </summary>
/// <returns>
/// TarBuffer record size.
/// </returns>
[Obsolete("Use RecordSize property instead")]
public int GetRecordSize()
{
return tarBuffer.RecordSize;
}
/// <summary>
/// Get the available data that can be read from the current
/// entry in the archive. This does not indicate how much data
/// is left in the entire archive, only in the current entry.
/// This value is determined from the entry's size header field
/// and the amount of data already read from the current entry.
/// </summary>
/// <returns>
/// The number of available bytes for the current entry.
/// </returns>
public long Available
{
get { return entrySize - entryOffset; }
}
/// <summary>
/// Skip bytes in the input buffer. This skips bytes in the
/// current entry's data, not the entire archive, and will
/// stop at the end of the current entry's data if the number
/// to skip extends beyond that point.
/// </summary>
/// <param name="skipCount">
/// The number of bytes to skip.
/// </param>
/// <param name="ct"></param>
private Task SkipAsync(long skipCount, CancellationToken ct) => SkipAsync(skipCount, ct, true).AsTask();
/// <summary>
/// Skip bytes in the input buffer. This skips bytes in the
/// current entry's data, not the entire archive, and will
/// stop at the end of the current entry's data if the number
/// to skip extends beyond that point.
/// </summary>
/// <param name="skipCount">
/// The number of bytes to skip.
/// </param>
private void Skip(long skipCount) =>
SkipAsync(skipCount, CancellationToken.None, false).GetAwaiter().GetResult();
private async ValueTask SkipAsync(long skipCount, CancellationToken ct, bool isAsync)
{
// TODO: REVIEW efficiency of TarInputStream.Skip
// This is horribly inefficient, but it ensures that we
// properly skip over bytes via the TarBuffer...
//
var length = 8 * 1024;
using (var skipBuf = ExactMemoryPool<byte>.Shared.Rent(length))
{
for (long num = skipCount; num > 0;)
{
int toRead = num > length ? length : (int)num;
int numRead = await ReadAsync(skipBuf.Memory.Slice(0, toRead), ct, isAsync).ConfigureAwait(false);
if (numRead == -1)
{
break;
}
num -= numRead;
}
}
}
/// <summary>
/// Return a value of true if marking is supported; false otherwise.
/// </summary>
/// <remarks>Currently marking is not supported, the return value is always false.</remarks>
public bool IsMarkSupported
{
get { return false; }
}
/// <summary>
/// Since we do not support marking just yet, we do nothing.
/// </summary>
/// <param name ="markLimit">
/// The limit to mark.
/// </param>
public void Mark(int markLimit)
{
}
/// <summary>
/// Since we do not support marking just yet, we do nothing.
/// </summary>
public void Reset()
{
}
/// <summary>
/// Get the next entry in this tar archive. This will skip
/// over any remaining data in the current entry, if there
/// is one, and place the input stream at the header of the
/// next entry, and read the header and instantiate a new
/// TarEntry from the header bytes and return that entry.
/// If there are no more entries in the archive, null will
/// be returned to indicate that the end of the archive has
/// been reached.
/// </summary>
/// <returns>
/// The next TarEntry in the archive, or null.
/// </returns>
public Task<TarEntry> GetNextEntryAsync(CancellationToken ct) => GetNextEntryAsync(ct, true).AsTask();
/// <summary>
/// Get the next entry in this tar archive. This will skip
/// over any remaining data in the current entry, if there
/// is one, and place the input stream at the header of the
/// next entry, and read the header and instantiate a new
/// TarEntry from the header bytes and return that entry.
/// If there are no more entries in the archive, null will
/// be returned to indicate that the end of the archive has
/// been reached.
/// </summary>
/// <returns>
/// The next TarEntry in the archive, or null.
/// </returns>
public TarEntry GetNextEntry() => GetNextEntryAsync(CancellationToken.None, false).GetAwaiter().GetResult();
private async ValueTask<TarEntry> GetNextEntryAsync(CancellationToken ct, bool isAsync)
{
if (hasHitEOF)
{
return null;
}
if (currentEntry != null)
{
await SkipToNextEntryAsync(ct, isAsync).ConfigureAwait(false);
}
byte[] headerBuf = ArrayPool<byte>.Shared.Rent(TarBuffer.BlockSize);
await tarBuffer.ReadBlockIntAsync(headerBuf, ct, isAsync).ConfigureAwait(false);
if (TarBuffer.IsEndOfArchiveBlock(headerBuf))
{
hasHitEOF = true;
// Read the second zero-filled block
await tarBuffer.ReadBlockIntAsync(headerBuf, ct, isAsync).ConfigureAwait(false);
}
else
{
hasHitEOF = false;
}
if (hasHitEOF)
{
currentEntry = null;
readBuffer?.Dispose();
}
else
{
try
{
var header = new TarHeader();
header.ParseBuffer(headerBuf, encoding);
if (!header.IsChecksumValid)
{
throw new TarException("Header checksum is invalid");
}
this.entryOffset = 0;
this.entrySize = header.Size;
string longName = null;
if (header.TypeFlag == TarHeader.LF_GNU_LONGNAME)
{
using (var nameBuffer = ExactMemoryPool<byte>.Shared.Rent(TarBuffer.BlockSize))
{
long numToRead = this.entrySize;
var longNameBuilder = StringBuilderPool.Instance.Rent();
while (numToRead > 0)
{
var length = (numToRead > TarBuffer.BlockSize ? TarBuffer.BlockSize : (int)numToRead);
int numRead = await ReadAsync(nameBuffer.Memory.Slice(0, length), ct, isAsync).ConfigureAwait(false);
if (numRead == -1)
{
throw new InvalidHeaderException("Failed to read long name entry");
}
longNameBuilder.Append(TarHeader.ParseName(nameBuffer.Memory.Slice(0, numRead).Span,
encoding));
numToRead -= numRead;
}
longName = longNameBuilder.ToString();
StringBuilderPool.Instance.Return(longNameBuilder);
await SkipToNextEntryAsync(ct, isAsync).ConfigureAwait(false);
await this.tarBuffer.ReadBlockIntAsync(headerBuf, ct, isAsync).ConfigureAwait(false);
}
}
else if (header.TypeFlag == TarHeader.LF_GHDR)
{
// POSIX global extended header
// Ignore things we dont understand completely for now
await SkipToNextEntryAsync(ct, isAsync).ConfigureAwait(false);
await this.tarBuffer.ReadBlockIntAsync(headerBuf, ct, isAsync).ConfigureAwait(false);
}
else if (header.TypeFlag == TarHeader.LF_XHDR)
{
// POSIX extended header
byte[] nameBuffer = ArrayPool<byte>.Shared.Rent(TarBuffer.BlockSize);
long numToRead = this.entrySize;
var xhr = new TarExtendedHeaderReader();
while (numToRead > 0)
{
var length = (numToRead > nameBuffer.Length ? nameBuffer.Length : (int)numToRead);
int numRead = await ReadAsync(nameBuffer.AsMemory().Slice(0, length), ct, isAsync).ConfigureAwait(false);
if (numRead == -1)
{
throw new InvalidHeaderException("Failed to read long name entry");
}
xhr.Read(nameBuffer, numRead);
numToRead -= numRead;
}
ArrayPool<byte>.Shared.Return(nameBuffer);
if (xhr.Headers.TryGetValue("path", out string name))
{
longName = name;
}
await SkipToNextEntryAsync(ct, isAsync).ConfigureAwait(false);
await this.tarBuffer.ReadBlockIntAsync(headerBuf, ct, isAsync).ConfigureAwait(false);
}
else if (header.TypeFlag == TarHeader.LF_GNU_VOLHDR)
{
// TODO: could show volume name when verbose
await SkipToNextEntryAsync(ct, isAsync).ConfigureAwait(false);
await this.tarBuffer.ReadBlockIntAsync(headerBuf, ct, isAsync).ConfigureAwait(false);
}
else if (header.TypeFlag != TarHeader.LF_NORMAL &&
header.TypeFlag != TarHeader.LF_OLDNORM &&
header.TypeFlag != TarHeader.LF_LINK &&
header.TypeFlag != TarHeader.LF_SYMLINK &&
header.TypeFlag != TarHeader.LF_DIR)
{
// Ignore things we dont understand completely for now
await SkipToNextEntryAsync(ct, isAsync).ConfigureAwait(false);
await tarBuffer.ReadBlockIntAsync(headerBuf, ct, isAsync).ConfigureAwait(false);
}
if (entryFactory == null)
{
currentEntry = new TarEntry(headerBuf, encoding);
readBuffer?.Dispose();
if (longName != null)
{
currentEntry.Name = longName;
}
}
else
{
currentEntry = entryFactory.CreateEntry(headerBuf);
readBuffer?.Dispose();
}
// Magic was checked here for 'ustar' but there are multiple valid possibilities
// so this is not done anymore.
entryOffset = 0;
// TODO: Review How do we resolve this discrepancy?!
entrySize = this.currentEntry.Size;
}
catch (InvalidHeaderException ex)
{
entrySize = 0;
entryOffset = 0;
currentEntry = null;
readBuffer?.Dispose();
string errorText = string.Format("Bad header in record {0} block {1} {2}",
tarBuffer.CurrentRecord, tarBuffer.CurrentBlock, ex.Message);
throw new InvalidHeaderException(errorText);
}
}
ArrayPool<byte>.Shared.Return(headerBuf);
return currentEntry;
}
/// <summary>
/// Copies the contents of the current tar archive entry directly into
/// an output stream.
/// </summary>
/// <param name="outputStream">
/// The OutputStream into which to write the entry's data.
/// </param>
/// <param name="ct"></param>
public Task CopyEntryContentsAsync(Stream outputStream, CancellationToken ct) =>
CopyEntryContentsAsync(outputStream, ct, true).AsTask();
/// <summary>
/// Copies the contents of the current tar archive entry directly into
/// an output stream.
/// </summary>
/// <param name="outputStream">
/// The OutputStream into which to write the entry's data.
/// </param>
public void CopyEntryContents(Stream outputStream) =>
CopyEntryContentsAsync(outputStream, CancellationToken.None, false).GetAwaiter().GetResult();
private async ValueTask CopyEntryContentsAsync(Stream outputStream, CancellationToken ct, bool isAsync)
{
byte[] tempBuffer = ArrayPool<byte>.Shared.Rent(32 * 1024);
while (true)
{
int numRead = await ReadAsync(tempBuffer, ct, isAsync).ConfigureAwait(false);
if (numRead <= 0)
{
break;
}
if (isAsync)
{
await outputStream.WriteAsync(tempBuffer, 0, numRead, ct).ConfigureAwait(false);
}
else
{
outputStream.Write(tempBuffer, 0, numRead);
}
}
ArrayPool<byte>.Shared.Return(tempBuffer);
}
private async ValueTask SkipToNextEntryAsync(CancellationToken ct, bool isAsync)
{
long numToSkip = entrySize - entryOffset;
if (numToSkip > 0)
{
await SkipAsync(numToSkip, ct, isAsync).ConfigureAwait(false);
}
readBuffer?.Dispose();
readBuffer = null;
}
/// <summary>
/// This interface is provided, along with the method <see cref="SetEntryFactory"/>, to allow
/// the programmer to have their own <see cref="TarEntry"/> subclass instantiated for the
/// entries return from <see cref="GetNextEntry"/>.
/// </summary>
public interface IEntryFactory
{
// This interface does not considering name encoding.
// How this interface should be?
/// <summary>
/// Create an entry based on name alone
/// </summary>
/// <param name="name">
/// Name of the new EntryPointNotFoundException to create
/// </param>
/// <returns>created TarEntry or descendant class</returns>
TarEntry CreateEntry(string name);
/// <summary>
/// Create an instance based on an actual file
/// </summary>
/// <param name="fileName">
/// Name of file to represent in the entry
/// </param>
/// <returns>
/// Created TarEntry or descendant class
/// </returns>
TarEntry CreateEntryFromFile(string fileName);
/// <summary>
/// Create a tar entry based on the header information passed
/// </summary>
/// <param name="headerBuffer">
/// Buffer containing header information to create an entry from.
/// </param>
/// <returns>
/// Created TarEntry or descendant class
/// </returns>
TarEntry CreateEntry(byte[] headerBuffer);
}
/// <summary>
/// Standard entry factory class creating instances of the class TarEntry
/// </summary>
public class EntryFactoryAdapter : IEntryFactory
{
Encoding nameEncoding;
/// <summary>
/// Construct standard entry factory class with ASCII name encoding
/// </summary>
[Obsolete("No Encoding for Name field is specified, any non-ASCII bytes will be discarded")]
public EntryFactoryAdapter()
{
}
/// <summary>
/// Construct standard entry factory with name encoding
/// </summary>
/// <param name="nameEncoding">The <see cref="Encoding"/> used for the Name fields, or null for ASCII only</param>
public EntryFactoryAdapter(Encoding nameEncoding)
{
this.nameEncoding = nameEncoding;
}
/// <summary>
/// Create a <see cref="TarEntry"/> based on named
/// </summary>
/// <param name="name">The name to use for the entry</param>
/// <returns>A new <see cref="TarEntry"/></returns>
public TarEntry CreateEntry(string name)
{
return TarEntry.CreateTarEntry(name);
}
/// <summary>
/// Create a tar entry with details obtained from <paramref name="fileName">file</paramref>
/// </summary>
/// <param name="fileName">The name of the file to retrieve details from.</param>
/// <returns>A new <see cref="TarEntry"/></returns>
public TarEntry CreateEntryFromFile(string fileName)
{
return TarEntry.CreateEntryFromFile(fileName);
}
/// <summary>
/// Create an entry based on details in <paramref name="headerBuffer">header</paramref>
/// </summary>
/// <param name="headerBuffer">The buffer containing entry details.</param>
/// <returns>A new <see cref="TarEntry"/></returns>
public TarEntry CreateEntry(byte[] headerBuffer)
{
return new TarEntry(headerBuffer, nameEncoding);
}
}
#region Instance Fields
/// <summary>
/// Flag set when last block has been read
/// </summary>
protected bool hasHitEOF;
/// <summary>
/// Size of this entry as recorded in header
/// </summary>
protected long entrySize;
/// <summary>
/// Number of bytes read for this entry so far
/// </summary>
protected long entryOffset;
/// <summary>
/// Buffer used with calls to <code>Read()</code>
/// </summary>
protected IMemoryOwner<byte> readBuffer;
/// <summary>
/// Working buffer
/// </summary>
protected TarBuffer tarBuffer;
/// <summary>
/// Current entry being read
/// </summary>
private TarEntry currentEntry;
/// <summary>
/// Factory used to create TarEntry or descendant class instance
/// </summary>
protected IEntryFactory entryFactory;
/// <summary>
/// Stream used as the source of input data.
/// </summary>
private readonly Stream inputStream;
private readonly Encoding encoding;
#endregion Instance Fields
}
}