Support: Work around missing SetFileInformationByHandle on Wine

[hans]

Summary

In r315079, fs::rename was reimplemented in terms of CreateFile and SetFileInformationByHandle. Unfortunately, the latter isn't supported by Wine. This adds a fallback to MoveFileEx for that case.

[pcc]

lib/Support/Windows/Path.inc

426

Wine returns ERROR_CALL_NOT_IMPLEMENTED if it does not support the call to SetFileInformationByHandle. Would it be simpler to detect that here and try the MoveFileEx if it fails in that way?

[hans]

lib/Support/Windows/Path.inc

426

Yes, that seems much nicer. Thanks!

[hans]

Check for ERROR_CALL_NOT_IMPLEMENTED instead.

[pcc]

LGTM

lib/Support/Windows/Path.inc

417

Perhaps more precise to compare EC against std::error_code(ERROR_CALL_NOT_IMPLEMENTED, std::system_category()) here.

[hans]

lib/Support/Windows/Path.inc

417

Will do.

Hmm actually, this means Wine will print to stderr complaining about the unimplementedness of the function. But maybe that's ok..

lib/Support/Windows/Path.inc

std::error_code rename(const Twine &From, const Twine &To) {
   if (!FromHandle)
     return mapWindowsError(GetLastError());
 
   // We normally expect this loop to succeed after a few iterations. If it
   // requires more than 200 tries, it's more likely that the failures are due to
   // a true error, so stop trying.
   for (unsigned Retry = 0; Retry != 200; ++Retry) {
     auto EC = rename_internal(FromHandle, To, true);
+
+    if (EC.value() == ERROR_CALL_NOT_IMPLEMENTED) {
+      // Wine doesn't support SetFileInformationByHandle in rename_internal.
+      // Fall back to MoveFileEx.
+      if (::MoveFileExW(WideFrom.begin(), WideTo.begin(),
+            MOVEFILE_REPLACE_EXISTING))
+        return std::error_code();
+      return mapWindowsError(GetLastError());
+    }
+
     if (!EC || EC != errc::permission_denied)
       return EC;
 
     // The destination file probably exists and is currently open in another
     // process, either because the file was opened without FILE_SHARE_DELETE or
     // it is mapped into memory (e.g. using MemoryBuffer). Rename it in order to
     // move it out of the way of the source file. Use FILE_FLAG_DELETE_ON_CLOSE
     // to arrange for the destination file to be deleted when the other process
     // closes it.