pgsql: More consistent behavior of GetDataDirectoryCreatePerm on Window

More consistent behavior of GetDataDirectoryCreatePerm on Windows

On Windows, GetDataDirectoryCreatePerm() just did nothing.  The way
the code in some callers is structured, this is the first function
that tries to access the data directory.  So it also ends up the place
that is responsible for reporting that a data directory does not exist
or similar.  Therefore, on Windows, these scenarios end up on
potentially completely different code paths.

To unify this, to make testing more consistent across platforms, have
GetDataDirectoryCreatePerm() run the stat() call on Windows as well,
even though it won't do anything with the result.  That way, file
system errors are reporting to callers in the same way as on
non-Windows.

Reviewed-by: Aleksander Alekseev <aleksander@timescale.com>
Discussion: https://www.postgresql.org/message-id/15a59bca-0383-183c-9383-0446da9b87e1%40eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/2c7c6c417fe655ab3fd4ca7f68ec22c913a2fe80

Modified Files
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src/common/file_perm.c | 14 +++++---------
1 file changed, 5 insertions(+), 9 deletions(-)