gh-133998: Fix gzip file creation when time is out of range

[adang1345]

If the system clock is set so that time.time() falls outside of the range 0 through 2**32-1, then creation of a GZIP-compressed file using gzip.GzipFile() would fail with the exception struct.error: 'L' format requires 0 <= number <= 4294967295. Fix this error.

If the mtime argument to gzip.GzipFile() is explicitly set to an out-of-range value, then the behavior is unchanged, and we continue raising the exception.

• Issue: gzip: cannot create file if mtime > 2106-02-07T06:28:15 #133998

---

📚 Documentation preview 📚: https://cpython-previews--134278.org.readthedocs.build/

[huwcbjones]

The docs are slightly wrong now that GzipFile.__init__ will raise a ValueError if the specified value is out of range.
I know you've documented it in the docstring for __init__, but I think it's worth clarifying here since we're already in the area.

[huwcbjones]

Ditto, see previous comment

[huwcbjones]

I think this should also be tweaked since the behaviour of providing an out-of-range mtime has changed

[serhiy-storchaka]

Test also for 2**32-0.1.

I do not think that raising ValueError in the GzipFile constructor is right. This does not solve the problem of the user passing stat().st_mtime or time.time().

There is other occurrence of this problem in compress().

[github-actions]

This PR is stale because it has been open for 30 days with no activity.

[read-the-docs-community]

Documentation build overview

📚 cpython-previews | 🛠️ Build #32800180 | 📁 Comparing e4e7d53 against main (65f9932)

  🔍 Preview build  

2 files changed

± library/gzip.html
± whatsnew/changelog.html

[miss-islington-app]

Thanks @adang1345 for the PR, and @serhiy-storchaka for merging it 🌮🎉.. I'm working now to backport this PR to: 3.15.
🐍🍒⛏🤖

[bedevere-app]

GH-150221 is a backport of this pull request to the 3.15 branch.

[bedevere-bot]

⚠️⚠️⚠️ Buildbot failure ⚠️⚠️⚠️

Hi! The buildbot AMD64 Debian root 3.x (tier-1) has failed when building commit 1daad8a.

What do you need to do:

1. Don't panic.
2. Check the buildbot page in the devguide if you don't know what the buildbots are or how they work.
3. Go to the page of the buildbot that failed (https://buildbot.python.org/#/builders/345/builds/14303) and take a look at the build logs.
4. Check if the failure is related to this commit (1daad8a) or if it is a false positive.
5. If the failure is related to this commit, please, reflect that on the issue and make a new Pull Request with a fix.

You can take a look at the buildbot page here:

https://buildbot.python.org/#/builders/345/builds/14303

Summary of the results of the build (if available):

==

Click to see traceback logs

Traceback (most recent call last):
  File "/root/buildarea/3.x.angelico-debian-amd64/build/Lib/test/support/__init__.py", line 948, in gc_collect
    gc.collect()
    ~~~~~~~~~~^^
ResourceWarning: unclosed file <_io.FileIO name=13 mode='wb' closefd=True>


Traceback (most recent call last):
  File "/root/buildarea/3.x.angelico-debian-amd64/build/Lib/test/support/__init__.py", line 948, in gc_collect
    gc.collect()
    ~~~~~~~~~~^^
ResourceWarning: unclosed file <_io.FileIO name=11 mode='wb' closefd=True>

[huwcbjones]

Thanks for getting the fix over the line @serhiy-storchaka! 😊