OSError: [Errno 22] Invalid argument when serving files with last modified time before 1969-12-31 12:00 UTC on windows

[EvanLai88]

Bug report

http.server.SimpleHTTPRequestHandler.send_head() does not check if a file's mtime is valid for gmtime() on windows.
An OSError: [Errno 22] Invalid argument exception will be raised which is normal according to the documentation.

cpython/Lib/http/server.py

Line 752 in ef633e5

fs.st_mtime, datetime.timezone.utc)

cpython/Lib/http/server.py

Line 766 in ef633e5

self.date_time_string(fs.st_mtime))

I encounter this error when using windows built-in unzip functionality to unzip a windows WireGuard client exported zip file.
The zip file does not contain any timestamp information. And windows will not auto fill timestamp information when unzipping.
And win32 api GetFileInformationByHandle will report back a timestamp of -11635213907.559603

Your environment

• CPython versions tested on: 3.10.9, 3.11.1, 3.12.0a4+
• Operating system and architecture: windows 11 pro 22h2 OS build 22621.1105 amd64

Linked PRs

• gh-101035: Check fs.st_mtime before use. #101036

[eryksun]

win32 api GetFileInformationByHandle will report back a timestamp of -11635213907.55960

That's a peculiar timestamp value. It corresponds to 1601-04-17 22:17:36.440399 (UTC).

A zero timestamp in Windows is relative to the Windows epoch, 1601-01-01 00:00:00 (UTC). As a Unix timestamp, that's -11644473600.0.