Fix CSV.Chunks crashing due to finalized buffer #763
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Fixes #734. The issue here is that on windows, we aggressively finalize the file source buffer as a way to "close" the file, since windows is much more picky when trying to modify an mmapped file after parsing. i.e. windows complains if you try to modify a file and there's still an mmap reference to it somewhere, so at the end of CSV.File, we call `finalize(buf)` to ensure it gets unmapped. The problem, however, is that `CSV.Chunks` calls `CSV.File` multiple times on the same `buf`, providing different starting/ending byte positions to read in chunks. So naturally, after the first chunk was read, the buffer was getting finalized and then the 2nd chunk immediately crashed trying to read its chunk from a finalized buffer.
Codecov Report
@@ Coverage Diff @@
## master #763 +/- ##
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Coverage 85.57% 85.57%
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Files 10 10
Lines 1948 1948
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Hits 1667 1667
Misses 281 281
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Fixes #734. The issue here is that on windows, we aggressively finalize
the file source buffer as a way to "close" the file, since windows is
much more picky when trying to modify an mmapped file after parsing.
i.e. windows complains if you try to modify a file and there's still an
mmap reference to it somewhere, so at the end of CSV.File, we call
finalize(buf)to ensure it gets unmapped. The problem, however, isthat
CSV.ChunkscallsCSV.Filemultiple times on the samebuf,providing different starting/ending byte positions to read in chunks.
So naturally, after the first chunk was read, the buffer was getting
finalized and then the 2nd chunk immediately crashed trying to read its
chunk from a finalized buffer.