[all-commits] [llvm/llvm-project] 177176: [Support] [Windows] Manually clean up temp files i...

[Martin Storsjö via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: 177176f75c6fa3f624d6d964b9d340ce39511565
      https://github.com/llvm/llvm-project/commit/177176f75c6fa3f624d6d964b9d340ce39511565
  Author: Martin Storsjö <martin at martin.st>
  Date:   2021-10-28 (Thu, 28 Oct 2021)

  Changed paths:
    M llvm/include/llvm/Support/FileSystem.h
    M llvm/lib/Support/Path.cpp
    M llvm/lib/Support/Windows/Path.inc

  Log Message:
  -----------
  [Support] [Windows] Manually clean up temp files if not setting delete disposition

Since D81803 / 79657e2339b58bc01fe1b85a448bb073d57d90bb, temp files
created on network shares don't set "Disposition.DeleteFile = true".
This flag normally takes care of removing the temp file both if the
process exits abnormally (either crashing or killed externally), and
when the file is closed cleanly.

For network shares, we voluntarily choose to not set the flag, and
if the operation to inspect the file handle (as a prerequisite to
setting the flag since 79657e2339b58bc01fe1b85a448bb073d57d90bb)
fails we also error out. In both of these cases, we can at least make
sure to remove the temp files when they are closed cleanly.

Adjust the semantics of "OF_Delete" to not set the delete
disposition, but only set the access mode for allowing deletion.
Move the call to setDeleteDisposition into TempFile::create,
where we can check if it failed, and if it did, set a flag noting
that the file should be removed manually at the end.

This does leak files on crash, but at least doesn't leak files
in regular successful runs. (Technically, the alternative codepath
could use the RemoveFileOnSignal function, but that might complicate
the TempFile implementation further.)

This fixes https://github.com/mstorsjo/llvm-mingw/issues/233 and
https://bugs.llvm.org/show_bug.cgi?id=52080.

Differential Revision: https://reviews.llvm.org/D111875