Refresh cached directory listing only after timeout.

[fangfufu]

Currently the LinkTable is pulled in regardless if it is timed out:

httpdirfs/src/link.c

Lines 603 to 633 in 9e383ad

	disk_linktbl = LinkTable_disk_open(unescaped_path);
	if (disk_linktbl) {
	/*
	* Check if the LinkTable needs to be refreshed based on timeout.
	*/
	time_t time_now = time(NULL);
	if (time_now - disk_linktbl->index_time > CONFIG.refresh_timeout) {
	lprintf(info, "time_now: %d, index_time: %d\n", time_now,
	disk_linktbl->index_time);
	lprintf(info, "diff: %d, limit: %d\n",
	time_now - disk_linktbl->index_time,
	CONFIG.refresh_timeout);
	LinkTable_free(disk_linktbl);
	}
	/*
	* Check if there are inconsistencies for the on-disk LinkTable
	*/
	if (disk_linktbl->num == linktbl->num) {
	LinkTable_free(linktbl);
	linktbl = disk_linktbl;
	skip_fill = 1;
	} else {
	lprintf(info,
	"disk_linktbl->num: %d, linktbl->num: %d\n",
	disk_linktbl->num, linktbl->num);
	lprintf(info, "Refreshing LinkTable for %s\n",
	url + ROOT_LINK_OFFSET);
	LinkTable_free(disk_linktbl);
	}
	}

This should be modified so the LinkTable is pulled in only after timeout.

[fangfufu]

The LinkTable's cache invalidation is fixed by f5ed128

I need to consider the invalidation of the files, and whether or not to incorporate the previous smart invalidation strategy.