Changes to metadata ignored when multiple modifications are performed under time limit

[LHLaurini]

$ mkdir version-dir
$ mkdir mountpoint
$ copyfs-mount $PWD/version-dir mountpoint
/home/user/test/version-dir
$ cd mountpoint/
$ echo content > file; chmod 777 file
$ ls -lh
total 4,0K
-rw-r--r-- 1 user user 8 jan 28 19:37 file
$ chmod 777 file
$ ls -lh
total 4,0K
-rwxrwxrwx 1 user user 8 jan 28 19:37 file

As you can see, creating a file and then immediately changing its mode, will cause the mode change to be ignored. This is a problem when running scripts.

The problem seems to be caused by trying to avoid creating unnecessary versions:

fuse-copyfs/create.c

Lines 148 to 150 in 66b8df2

	/* Check timestamp in order not to create bogus new versions */
	if (time(NULL) - metadata->md_timestamp < TIME_LIMIT)
	return 0;

If I set TIME_LIMIT to 0, the problem disappears.

[cognusion]

Yes, this is a known issue. It results in the best experience for 99.9999% of operations but unfortunately does create an eyesore for the odd case.

I will gladly accept a PR that allows dynamic changes to temporarily adjust the value, but am resistant to changes that are either hard-coded or require remounting.

One solution, if you're looking for brain food, is to externalize TIME_LIMIT so in the event you want to run a script that needs to make microchanges to the file, you could do e.g. TIME_LIMIT=0 ./my script.sh.