Fix error in decompressing RDS files that decompress to more than UINT_MAX bytes #49
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…T_MAX bytes This was caused by truncating assignment of an 8 byte ssize_t to a 4 byte uInt. Fixed by doing saturating assignment instead. The surrounding decompression loop ensures that larger files can be decompressed (in chunks).
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When decompressing RDS files that decompress to more than
UINT_MAXbytes (~4 GB), librdata incorrectly returns an errorCould not open file.This is caused by truncating assignment of an 8 byte
ssize_tto a 4 byteuInt. I fixed this by doing saturating assignment instead. The surrounding decompression loop ensures that larger files can be decompressed (in chunks).C.f https://github.com/madler/zlib/blob/develop/uncompr.c#L58 for a reference implementation that works this way.
I only fixed the bug that I could personally confirm fixed with my changes, the analogous functions using gzip or lzma decompression likely still have similar bugs.
Please consider turning on the
-Wconversionflag for gcc, as this correctly warns about the assignment that caused this bug. When briefly turning on-Wconversion, I got a large number of warnings about other lines in the codebase.