In some cases (such as `ostree-sysroot-cleanup.c`), the surrounding
code would be substantially cleaner if it was also ported to
fd-relative, but I'm going to do that in a separate patch.
That way these patches are easier to review for mechanical
correctness. I used an Emacs keyboard macro as the poor man's
[Coccinelle](http://coccinelle.lip6.fr/).
Since we hard-depend on GLib 2.40, we can start using GSubprocess.
This is part of dropping our dependency on libgsystem, which is
deprecated in favor of libglnx (as well as migrating things to GLib).
I'd like to encourage people to make OSTree-managed systems more
strictly read-only in multiple places. Ideally everywhere is
read-only normally besides `/var/`, `/tmp/`, and `/run`.
`/boot` is a good example of something to make readonly. Particularly
now that there's work on the `admin unlock` verb, we need to protect
the system better against things like `rpm -Uvh kernel.rpm` because
the RPM-packaged kernel won't understand how to do OSTree right.
In order to make this work of course, we *do* need to remount `/boot`
as writable when we're doing an upgrade that changes the kernel
configuration. So the strategy is to detect whether it's read-only,
and if so, temporarily mount read-write, then remount read-only when
the upgrade is done.
We can generalize this in the future to also do `/etc` (and possibly
`/sysroot/ostree/` although that gets tricky).
One detail: In order to detect "is this path a mountpoint" is
nontrivial - I looked at copying the systemd code, but the right place
is to use `libmount` anyways.
It used to be allowed to run something like "ostree remote refs" on
a read-only (e.g. system) repo. However, the summary cache caused that to
break. This commit just makes it not save the cache if we get some kind
of permission error when writing it. It'll still work, even without the
cache.
https://bugzilla.gnome.org/show_bug.cgi?id=763855
It allows an optimization to skip the download of the summary file
if its .sig file is unchanged.
Downloading the .sig file is much cheaper than downloading the summary
file from repositories with many branches.
https://bugzilla.gnome.org/show_bug.cgi?id=762973
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
This will allow daemons like rpm-ostree to detect if there are any new
deployments efficiently, in combination with using inotify. If there
are any changes, rpm-ostree wants publish them on DBus.
While we're here, add some changes to start doing unit C testing of
the sysroot API.
And change the command line to use it. rpm-ostree had a copy
of this code, and thus there's a clear reason to have an API.
While we're moving this into API, ensure the mtime on deploy is bumped
after an osname is created, so that daemons like rpm-ostree can notice
changes. (In reality, creating the directory should do this, but
let's be double sure)
This allows other processes (e.g. rpm-ostreed) to monitor for external
changes (e.g. if someone does `ostree admin undeploy`) in a relatively
sane fashion.
Specifically, I'm trying to fix:
https://github.com/projectatomic/rpm-ostree/issues/220
It accepts a `flags` argument to control its behavior. Differently
from `ostree_repo_list_refs`, the `refspec_prefix` is not removed from
the results.
Signed-off-by: Giuseppe Scrivano <gscrivan@redhat.com>
I plan to use this in rpm-ostree at least for two reasons:
- To find the mtime on the repo
- To use the tmp/ directory to stage content (but we should eventually
add a better API)
As rpm-ostree evolves, it keeps driving API additions to libostree.
This creates a relatively tight coupling.
However, if delivering via e.g. RPM, unless one manually remembers to
increment the `Requires:` in the spec file, it's possible for the two
to become desynchronized.
RPM handles versioned symbols and will ensure a dependency if the
application starts using a newer version.
To implement this, switch to `-fvisibility=hidden`, along with an
annotation in the header, and finally add a `.sym` file.
This matches what other projects like systemd and libvirt do.
Although rather than attempting to retroactively version symbols, glom
them all onto the current one.
I see when analyzing a delta here that due to byteswapping a negative
compression ratio of 540%, 66%, and 28%. Let's arbitrarily pick 20%
as a threshold for detecting byetswapping.
If the average object size is greater than 4GiB, let's assume we're
dealing with opposite endianness. I'm fairly confident no one is
going to be shipping peta- or exa- byte size ostree deltas, period.
Past the gigabyte scale you really want bittorrent or something.
xdg-app passed this a filename directly, and in this case it should be
used as is. This regressed to always look for "superblock" in the same
directory as the passed in filename.
https://bugzilla.gnome.org/show_bug.cgi?id=762617
Some Docker layers are just metadata in the `layer.json`. If one is
mapping Docker layers to OSTree commits, one needs to create a dummy
root directory, because OSTree doesn't support metadata-only commits.
Let's just push that logic down here because it's easier than special
casing it in higher levels.
One of the design goals with deltas was not just wire efficiency,
but also having all the data up front about how much data would
be transferred before starting.
Let's expose that better by adding a `dry-run` option to the pull API.
This requires static deltas to be useful. Basically we simply call
the progress callback once with the data from the superblock.
For a production release repository, most OS vendors would want
to just always use static deltas. Add the ability for the pulls to
require it.
(I think I'll also add a summary key for this actually in addition,
so the repo manager can force it too)
If ostree is run in a test setup where it operates as root in a tmp
directory, it might cause issues to flag the deployments as immutable.
The test harness might simply be doing an `rm -rf` (effectively the case
for gnome-desktop-testing-runner), which will then fail.
We add a new debug option to the ostree_sysroot object using GLib's
GDebugKey functionality to allow our tests to communicate to ostree that
we don't want immutable deployments.
This is a more flexible version of the previous
ostree_repo_write_archive_to_mtree() which took a file reference.
This has an extensible options structure, and in particular
now supports `ignore_unsupported_content`.
I plan to use this for importing Docker images which contain device
nodes. (There's no reason for container images to have those, so
we'll just ignore them).
Also here, just like the export variant, the caller is responsible for
setting up libarchive.
I was going to add new API for importing, and it was really confusing
that what I think of now as import and export both had "write" in the
name. It's just clearer to talk about the direction.
At the same time, include `Export` in the options structure.
This isn't an ABI break as the API isn't in a release.
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.
I don't know why we didn't do this a long time ago. This extends the
pull API to allow grabbing a specific commit, and will set the branch
to it. There's some support for this in the deploy engine, but there
are a lot of reasons to support it for raw pulls (such as subset
mirroring cases).
In fact I'm thinking we should also have the override-version logic
here too.
NOTE: One thing I debated here is inventing a new syntax on the
command line. Git doesn't seem to have this functionality (probably
because it'd be rarely used). The '@' character at least doesn't
conflict with anything.
Anyways, I wanted this for some other test cases. Without this,
writing tests that go between different commits is more awkward as one
must generate the content in one repo, then pull downstream, then
generate more content, then pull again. But now I can just keep track
of commit IDs and do exactly what I want without synchronizing the
tests.
At the moment I'm looking at using rpm-ostree to manage RPM inputs
which can then be converted into Docker images. It's most convenient
if we can stream directly out of libostree rather than doing a
checkout + tar combination.
There are also backup/debugging etc. reasons to implement `export` as
well.
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.
Colin Walters
Alexander Larsson
Giuseppe Scrivano
Jonathan Lebon