Prevent PHP request to get killed when using fclose callback

[PVince81]

Description

When cancelling a download or closing the connection too quickly after a download, the PHP process might get killed. In these cases the fclose code does not run any more and the locks are not released.
This workaround adds ignore_user_abort(true) to tell PHP to continue working even when the connection was closed. This makes sure that resources get freed properly and no weird GC-induced bugs will appear as reported in #22370

Related Issue

Partial fix for #22370

Motivation and Context

How Has This Been Tested?

See #22370 (comment).
Need to abort download connections.
Also tested with smashbox: owncloud/smashbox#151

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist:

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have read the CONTRIBUTING document.
• I have added tests to cover my changes.
• All new and existing tests passed.

Backports

• stable9.1 (note: the fix was tested on that version on the reporter's envs)
• stable9

Please review @jvillafanez @DeepDiver1975 @VicDeo @PhilippSchaffrath @butonic

[mention-bot]

@PVince81, thanks for your PR! By analyzing the history of the files in this pull request, we identified @DeepDiver1975, @tanghus and @karakayasemi to be potential reviewers.

[DeepDiver1975]

should we put this call to all entrypoints where we set the execution time to 0?

[PVince81]

Hmm good point. If we set execution time to 0 in these entry points it means we already expect the call to never be killed.

[PVince81]

apps/dav/appinfo/v1/webdav.php|26| set_time_limit(0);
apps/dav/appinfo/v2/remote.php|23| set_time_limit(0);
lib/private/legacy/files.php|149| set_time_limit(0);
lib/private/legacy/files.php|167| set_time_limit($executionTime);
lib/base.php|546| @set_time_limit(3600);

[PVince81]

@DeepDiver1975 2a4dffc

[PVince81]

Raised #26790 to look into detecting aborted connections and making shortcuts for faster cleanup

[PVince81]

Rebased, please review.

@jvillafanez has voiced some objections here #26790 (comment)
Would be good to clarify in this PR here

[PVince81]

Please re-review @butonic @jvillafanez @DeepDiver1975.

[jvillafanez]

No better alternatives, so let's move with this 👍

[PVince81]

stable9.1: #26939

[PVince81]

stable9: #26962

[lock]

This thread has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.