Programs like `useradd` try to `open(/etc/passwd, O_RDWR)` to append,
which didn't work with rofiles-fuse. Thinking about this, I realized
that there's a simpler algorithm for "can we write to this file" which
is "does it have a hardlink count <= 1"?
Switching to this both drops complexity (we no longer need to keep a
hash table of files we created), and also lets useradd work.
Closes: #462
Approved by: jlebon
The program is called ro*files* and ostree creates physical
copies of directories, so changing them is fine.
I hit this when trying to do a copy checkout onto an rofiles-fuse
mount.
Closes: #368
Approved by: jlebon
I was getting a compilation error with the GCC hardening flags which
look for a missing mode with `O_CREAT`. The right fix here is to drop
`O_CREAT`, as truncate() should throw `ENOENT` if the file doesn't
exist.
While it's not strictly tied to OSTree, let's move
https://github.com/cgwalters/rofiles-fuse in here because:
- It's *very* useful in concert with OSTree
- It's tiny
- We can reuse OSTree's test, documentation, etc. infrastructure
One thing to consider also is that at some point we could experiment
with writing a FUSE filesystem for OSTree. This could internalize a
better equivalent of `--link-checkout-speedup`, but on the other hand,
the cost of walking filesystem trees for these types of operations is
really quite small.
But if we did decide to do more FUSE things in OSTree, this is a step
towards that too.
Simon McVittie
Colin Walters
Alexander Larsson
Giuseppe Scrivano