according to spec tag 0x00000000 is not valid

[fsulima]

I have encountered crash in lfs_dir_fetchmatch when retrieved tag was 0x00000000 and callback was 0x0. This is the suggested fix.

[geky]

Hi @fsulima, thanks for creating a PR. This actually looks like it is a duplicate of #337 (discussion here #184).

Let me know if I'm incorrect.

[fsulima]

Hello @geky , you are correct, but it looks like the fix I suggest is little more general.

[geky]

That's true, though I'm not sure it's needed. As of #337, littlefs does not rely on tag 0x00000000 being invalid.

It isn't a valid tag in the sense that littlefs should never emit it (as a side-effect of the tag encoding), but this is just intended as a convenience for external tools and future filesystem development.

[geky]

Closing as resolved by #337, feel free to reopen if I've made a mistake.