zip seems to decode dos time incorrectly? or not ...

[ruslandoga]

👋

I have a Zip with a file dated (according to zipdetails) 'Tue Mar 4 13:20:00 2025', but zip thinks it's {{2025, 3, 4}, {13, 19, 60}} which results in zip:unzip/1 returning {error, badarg}.

I think this might be the offending function:

zip:dos_date_time_to_datetime(23140, 27262) -> {{2025, 3, 4}, {13, 19, 60}}

After #8537 it multiplies Seconds by two. Should it roll over to the next minute if the result is 60 or maybe just cap it at 59?

otp/lib/stdlib/src/zip.erl

Lines 2463 to 2472 in e8473e6

	%% convert between erlang datetime and the MSDOS date and time
	%% that's stored in the zip archive
	%% MSDOS Time MSDOS Date
	%% bit 0 - 4 5 - 10 11 - 15 16 - 20 21 - 24 25 - 31
	%% value second minute hour day (1 - 31) month (1 - 12) years from 1980
	dos_date_time_to_datetime(DosDate, DosTime) ->
	<<Hour:5, Min:6, Sec:5>> = <<DosTime:16>>,
	<<YearFrom1980:7, Month:4, Day:5>> = <<DosDate:16>>,
	{{YearFrom1980+1980, Month, Day},
	{Hour, Min, Sec * 2}}.

Or is my Zip just malformed?