Function robust_rename

util1.c:547–586

Returns 0 on successful rename, 1 if we successfully copied the file * across filesystems, -2 if copy_file() failed, and -1 on other errors. * If partialptr is not NULL and we need to do a copy, copy the file into * the active partial-dir instead of over the destination file. */

 * If partialptr is not NULL and we need to do a copy, copy the file into
 * the active partial-dir instead of over the destination file. */
int robust_rename(const char *from, const char *to, const char *partialptr,
		  int mode)
{
	int tries = 4;

	/* A resumed in-place partial-dir transfer might call us with from and
	 * to pointing to the same buf if the transfer failed yet again. */
	if (from == to)
		return 0;

	while (tries--) {
		if (do_rename_at(from, to) == 0)
			return 0;

		switch (errno) {
#ifdef ETXTBSY
		case ETXTBSY:
			if (robust_unlink(to) != 0) {
				errno = ETXTBSY;
				return -1;
			}
			errno = ETXTBSY;
			break;
#endif
		case EXDEV:
			if (partialptr) {
				if (!handle_partial_dir(partialptr,PDIR_CREATE))
					return -2;
				to = partialptr;
			}
			if (copy_file(from, to, -1, mode) != 0)
				return -2;
			do_unlink_at(from);
			return 1;
		default:
			return -1;
		}
	}
	return -1;
}

static pid_t all_pids[10];
static int num_pids;