A pure CLS-compliant C# implementation of the Named Binary Tag (NBT) format specification commonly used with Minecraft applications, allowing easy reading/writing streams and serialization to other formats.
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BaseStream.Read reads less bytes than expected due to breaking change in .NET 6 #3
There was a breaking change in .NET 6 in DeflateStream and GZipStream. These streams can now read less bytes than requested by the Read methods count parameter. You now have to call the Read method multiple times until your buffer is filled or 0 is returned (end of base stream).
In TagReader there are a few instances where BaseStream.Read is used but the return value is ignored. For example: When reading Minecraft chunk files the NBT data is compressed by GZipStream or ZLibStream(uses DeflateStream). Chunk files can contain really long LongArrayTags that are read in a single Read call. Due to the .NET 6 change it is possible that not all bytes are read in a single call. This will mess up the read data, the stream position and the Crc in ZLibStream that will throw an InvalidDataException.
If required I can upload a region file and an example code to reproduce the problem.
Possible solutions:
Create an extension method e.g. ReadFixedLength with the same signature as Stream.Read but without return value. This will call Stream.Read in a loop until all count bytes are read. This should throw an EndOfStreamException if it couldn't read the required number of bytes from the base steam.
There was a breaking change in .NET 6 in
DeflateStreamandGZipStream. These streams can now read less bytes than requested by theReadmethodscountparameter. You now have to call theReadmethod multiple times until your buffer is filled or 0 is returned (end of base stream).In
TagReaderthere are a few instances whereBaseStream.Readis used but the return value is ignored. For example: When reading Minecraft chunk files the NBT data is compressed byGZipStreamorZLibStream(usesDeflateStream). Chunk files can contain really longLongArrayTags that are read in a singleReadcall. Due to the .NET 6 change it is possible that not all bytes are read in a single call. This will mess up the read data, the stream position and the Crc inZLibStreamthat will throw anInvalidDataException.If required I can upload a region file and an example code to reproduce the problem.
Possible solutions: Create an extension method e.g.
ReadFixedLengthwith the same signature asStream.Readbut without return value. This will callStream.Readin a loop until allcountbytes are read. This should throw anEndOfStreamExceptionif it couldn't read the required number of bytes from the base steam.