TarReader stops enumerating entries when stream is unseekable #74728
Description
Description
When enumerating a tar file using TarReader and GetNextEntryAsync, once ExtractToFileAsync is called on one entry then the enumerating stops.
However, if the source tar stream is copied into a MemoryStream then it works as expected.
Reproduction Steps
using System.Formats.Tar;
using static System.Console;
using System.IO.Compression;
// 🎸 Tar Issue that I wish you saw... 🎶
await using var s = File.OpenRead("./my-file.tar.gz");
await using var gz = new GZipStream(s, CompressionMode.Decompress, true);
// Change to true to see what should happen
var copyToMemoryStream = false;
var tarStream = copyToMemoryStream ? await CopyToMemoryStream(gz) : gz;
await using var tarReader = new TarReader(tarStream, true);
var temp = Directory.CreateDirectory("temp").FullName;
var entriesCount = 0;
while (await tarReader.GetNextEntryAsync() is { } entry)
{
WriteLine(entry.Name);
entriesCount++;
var destination = Path.Combine(temp, entry.Name);
if (entry.EntryType is TarEntryType.Directory)
{
Directory.CreateDirectory(destination);
}
else
{
await entry.ExtractToFileAsync(destination, true);
}
}
WriteLine();
WriteLine("Should have encountered 140 tar entries");
WriteLine($"Actual: {entriesCount}");
async Task<Stream> CopyToMemoryStream(Stream source)
{
var destination = new MemoryStream();
await source.CopyToAsync(destination);
destination.Seek(0, SeekOrigin.Begin);
return destination;
}
Repro hereExpected behavior
In the code example provided, we should see the entries count being 140, and it indeed is when we copy the source to a MemoryStream.
Actual behavior
The TarReader stops returning entries after the first one has been extracted, resulting in an entries count of 7 (we called ExtractToFileAsync on the 7th entry).
Regression?
No response
Known Workarounds
Copy tar stream into a MemoryStream before using TarReader
Configuration
No response