Use make_tempname file descriptor in smart_rename
This patch makes use of the temp file descriptor in smart_rename
rather than reopening the file. I don't believe there is a security
issue in reopening the file, but this way is one less directory
operation. The patch also attempts to preserve S_ISUID and S_ISGID.
PR 27456
* bucomm.h (smart_rename): Update prototype.
* rename.c (smart_rename): Add fromfd and preserve_dates params.
Pass fromfd and target_stat to simple_copy. Call set_times
when preserve_dates.
(simple_copy): Accept fromfd rather than from filename. Add
target_stat param. Rewind fromfd rather than opening. Open
"to" file without O_CREAT. Try to preserve S_ISUID and S_ISGID.
* ar.c (write_archive): Rename ofd to tmpfd. Dup tmpfd before
closing output temp file, and pass tmpfd to smart_rename.
* arsup.c (temp_fd): Rename from real_fd.
(ar_save): Dup temp_fd and pass to smart_rename.
* objcopy.c (strip_main, copy_main): Likewise, and pass
preserve_dates.
(cherry picked from commit
c42c71a1527dd70417d3966dce7ba9edbcf4bdb4)