Rppt: /* Linux Plumbers Conference 2018 */

2017-09-28T07:38:32Z

Rppt:

== Set up working environment ==

Although criu could be run as non-root (see [[Security]]), development is better to be done as root. For example, some tests require root. So, it would be a good idea to set up some recent Linux distro on a virtual machine.

== Get the source code ==

The CRIU sources are tracked by Git. Official CRIU repo is at [https://github.com/checkpoint-restore/criu https://github.com/checkpoint-restore/criu].

The repository may contain multiple branches. Development happens in the '''criu-dev''' branch.

To clone CRIU repo and switch to the proper branch, run:

<pre><nowiki>
git clone https://github.com/checkpoint-restore/criu criu
cd criu
git checkout criu-dev
</nowiki></pre>

== Compile ==

First, you need to install compile-time dependencies. Check [[Installation#Dependencies]] for more info.

To compile CRIU, run:

make

This should create the <code>./criu/criu</code> executable.

== Edit the source code ==

If you use ctags, you can generate the ctags file by running

make tags

When you change the source code, please keep in mind the following code conventions:

* we prefer tabs and indentations to be 8 characters width
* consider reading [https://www.kernel.org/doc/Documentation/CodingStyle Linux kernel coding style].

Other conventions can be learned from the source code itself. In short, make sure your new code
looks similar to what is already there.

== Test your changes ==

CRIU comes with an extensive test suite. To check whether your changes introduce any regressions, run

make test

The command runs [[ZDTM Test Suite]]. Check for any error messages produced by it.

In case you'd rather have someone else run the tests, you can use travis-ci for your
own github fork of CRIU. It will check the compilation for various supported platforms,
as well as run most of the tests from the suite. See https://travis-ci.org/xemul/criu
for more details.

== Make a patch ==

To create a patch, run

git format-patch

You might need to read GIT documentation on how to prepare patches
for mail submission. Take a look at http://book.git-scm.com/ and/or
http://git-scm.com/documentation for details. It should not be hard
at all.

== Sign your work ==

To improve tracking of who did what, we ask you to sign off the patches
that are to be emailed.

The sign-off is a simple line at the end of the explanation for the
patch, which certifies that you wrote it or otherwise have the right to
pass it on as an open-source patch. The rules are pretty simple: if you
can certify the below:

<div class="toccolours mw-collapsible mw-collapsed" style="width: 46em;">
'''Developer's Certificate of Origin 1.1'''
<div class="mw-collapsible-content">
By making a contribution to this project, I certify that:

(a) The contribution was created in whole or in part by me and I
have the right to submit it under the open source license
indicated in the file; or

(b) The contribution is based upon previous work that, to the best
of my knowledge, is covered under an appropriate open source
license and I have the right under that license to submit that
work with modifications, whether created in whole or in part
by me, under the same open source license (unless I am
permitted to submit under a different license), as indicated
in the file; or

(c) The contribution was provided directly to me by some other
person who certified (a), (b) or (c) and I have not modified
it.

(d) I understand and agree that this project and the contribution
are public and that a record of the contribution (including all
personal information I submit with it, including my sign-off) is
maintained indefinitely and may be redistributed consistent with
this project or the open source license(s) involved.
</div></div>
then you just add a line saying

Signed-off-by: Random J Developer <random at developer.example.org>

using your real name (please, no pseudonyms or anonymous contributions if
it possible).

Hint: you can use <code>git commit -s</code> to add Signed-off-by line to your
commit message. To append such line to a commit you already made, use
<code>git commit --amend -s</code>.

<div class="toccolours mw-collapsible mw-collapsed" style="width: 46em;">
'''Example patch message'''
<div class="mw-collapsible-content">

From: Random J Developer <random at developer.example.org>
Subject: [PATCH] Short patch description

Long patch description (could be skipped if patch
is trivial enough)

Signed-off-by: Random J Developer <random at developer.example.org>
---
Patch body here
</div></div>

== Mail patches ==

The patches should be sent to CRIU development mailing list, <code>criu AT openvz.org</code>. Note that you need to be subscribed first in order to post. The list web interface is available at https://openvz.org/mailman/listinfo/criu; you can also use standard mailman aliases to work with it.

Please make sure the email client you're using doesn't screw your patch (line wrapping and so on).

== Wait for response ==

Be patient. Most CRIU developers are pretty busy people so if
there is no immediate response on your patch — don't be surprised,
sometimes a patch may fly around a week before it gets reviewed.

== Continuous integration ==

''Main article: [[Continuous integration]]''

CRIU tests are run for each series sent to the mailing list. If you get a message from our patchwork that patches failed to pass the tests, you have to investigate what is wrong.

We also recommend you to [[Continuous integration#Enable Travis CI for your repo|enable Travis CI for your repo]] to check patches in your git branch, before sending them to the mailing list.

[[Category:Development]]