Disposing TarEntry.DataStream causes TarReader.GetNextEntry to throw ObjectDisposedException #101948
Description
Description
When disposing the stream of a single TarEntry, I cannot advance the TarReader to the next entry.
Consider the following sample:
using (var tarReader = new TarReader(unseekableStream))
{
TarEntry? entry;
while ((entry = tarReader.GetNextEntry()) != null)
{
Stream s = entry.DataStream;
s.CopyTo(someOtherStream);
s.Dispose();
}
}This will throw
System.ObjectDisposedException
HResult=0x80131622
Message=Cannot access a disposed object.
Object name: 'System.Formats.Tar.SubReadStream'.
Source=System.Private.CoreLib
StackTrace:
System.Private.CoreLib.dll!System.ThrowHelper.ThrowObjectDisposedException(object instance) Line 458
at /_/src/libraries/System.Private.CoreLib/src/System/ThrowHelper.cs(458)
System.Private.CoreLib.dll!System.ObjectDisposedException.ThrowIf(bool condition, object instance) Line 61
at /_/src/libraries/System.Private.CoreLib/src/System/ObjectDisposedException.cs(61)
System.Formats.Tar.dll!System.Formats.Tar.SubReadStream.Position.get() Line 52
at /_/src/libraries/System.Formats.Tar/src/System/Formats/Tar/SubReadStream.cs(52)
System.Formats.Tar.dll!System.Formats.Tar.TarReader.AdvanceDataStreamIfNeeded() Line 228
at /_/src/libraries/System.Formats.Tar/src/System/Formats/Tar/TarReader.cs(228)
System.Formats.Tar.dll!System.Formats.Tar.TarReader.GetNextEntry(bool copyData) Line 133
at /_/src/libraries/System.Formats.Tar/src/System/Formats/Tar/TarReader.cs(133)
The suspect code is here:
runtime/src/libraries/System.Formats.Tar/src/System/Formats/Tar/TarReader.cs
Lines 200 to 237 in 84b3339
Reproduction Steps
See above
Expected behavior
No exception thrown
Actual behavior
ObjectDisposedException
Regression?
No
Known Workarounds
Copy the entry to a memory stream. Copy the archive to a memory stream before opening (so it is seek-able). Etc
Configuration
No response
Other information
I noticed when debugging this that the state of the SubReadStream was the following:
Note that _positionInSuperStream is the same as _endInSuperStream. I noticed that the HasReachedEnd property is checked before accessing Position which will throw. It seems like HasReachedEnd checks both the fields mentioned, but will only treat it as true if greater, perhaps it should have been greater or equal?