xref: /freebsd/CONTRIBUTING.md (revision 3c4ba5f55438f7afd4f4b0b56f88f2bb505fd6a6)
1# Contribution Guidelines for GitHub
2
3## General Contributions to FreeBSD
4
5Please read the guidelines in [Contributing to FreeBSD](https://docs.freebsd.org/en/articles/contributing/)
6for all the ways you can contribute to the project, how the project is organized,
7how to build different parts of the project, etc. The
8[developer's handbook](https://docs.freebsd.org/en/books/developers-handbook/)
9is another useful resource.
10
11## GitHub Pull Requests
12
13Presently, GitHub 'freebsd-src' repository is one of the publish-only services
14for the FreeBSD 'src' repository the project uses to promote collaboration and
15contribution.  Pull requests that need little developer time, are generally
16small, and have limited scope should be submitted. Do not submit pull request
17that are a problem reports, works in progress, changes that are controversial
18and need discussion, changes require specialize review, or are security related.
19
20A pull request will be considered if:
21
22* It is ready or nearly ready to be committed. A committer should be able to land the pull request with less than 10 minutes of additional work.
23* It passes all the GitHub CI jobs.
24* You can respond to feedback quickly.
25* It touches fewer than about 10 files and the changes are less than about 200 lines. Changes larger than this may be OK, or you may be asked to submit multiple pull requests of a more manageable size.
26* Each logical change is a separate commit within the pull request. Commit messages for each change should follow the [commit log message guide](https://docs.freebsd.org/en/articles/committers-guide/#commit-log-message).
27* All commits have your name and valid email address as you would like to see them in the FreeBSD repository as the author. Fake github.com addresses cannot be used.
28* The scope of the pull request should not change during review. If the review suggests changes that expand the scope, please create an independent pull request.
29* Fixup commits should be squashed with the commit they are fixing. Each commit in your branch should be suitable for FreeBSD's repository.
30* Commits should include one or more `Signed-off-by:` lines with full name and email address certifying [Developer Certificate of Origin](https://developercertificate.org/).
31* The commits follow FreeBSD's style guide. See [Style](#Style).
32* Run tools/build/checkstyle9.pl on your git branch and eliminate all errors
33* The commits should not introduce trailing white space.
34* If the commmit fixes a bug, please add 'PR: <bugnumber>' to the comment message.
35* If there's a code review in phabricator, please include a link as a 'Differential Revision: ' line.
36
37When updating your pull request, please rebase with a forced push rather than a
38merge commit.
39
40More complex changes may be submitted as pull requests, but they may be closed
41if they are too large, too unwieldy, become inactive, need further discussion in
42the community, or need extensive revision.  Please avoid creating large,
43wide-ranging cleanup patches: they are too large and lack the focus needed for a
44good review.  Misdirected patches may be redirected to a more appropriate forum
45for the patch to be resolved.
46
47Please make sure that your submissions compile and work before submitting. If
48you need feedback, a pull request might not be the right place (it may just be
49summarily closed if there are too many obvious mistakes).
50
51If you want to cleanup style or older coding conventions in preparation for some
52other commit, please go ahead and prepare those patches. However, please avoid just
53cleaning up to make it cleaner, unless there's a clear advantage to doing
54so. While the project strives to have a uniform coding style, our style offers a
55range of choices making some 'cleanups' ambiguous at best. Also, some files have
56their own consistent style that deviates from style(9). Style changes take
57volunteer time to process, but that time can be quite limited, so please be
58respectful.
59
60The current theory for pull requests on GitHub is to facilitate inclusion in the
61project. The guidelines are streamlined for quick decisions about each pull
62request. Unless explicitly stated, rejection here as "not ready" or "too large"
63does not mean the project is uninterested in the work, it just means the
64submission does not meet the limited scope for pull requests accepted
65here. Sometimes it is easier to review a GihHub pull request than to do the
66review in Phabricator, so that's also allowed.
67
68## Style
69
70Avoid adding trailing newlines and whitespace. These slow down the integration
71process and are a distraction. `git diff` will highlight them in red, as will
72the Files Changed tab in the pull request.
73
74For C programs, see [style(9)](https://man.freebsd.org/cgi/man.cgi?query=style&sektion=9)
75for details. You can use [Clang format](https://clang.llvm.org/docs/ClangFormat.html)
76with the top level .clang-format file if you are unsure. The
77[git clang-format](https://github.com/llvm-mirror/clang/blob/master/tools/clang-format/git-clang-format)
78command can help minimize churn by only formatting the areas nearby the changes. While
79not perfect, using these tools will maximize your chances of not having style
80comments on your pull requests.
81
82For Makefiles changes, see
83[style.Makefile(5)](https://man.freebsd.org/cgi/man.cgi?query=style.Makefile&sektion=5)
84for details. FreeBSD's base system uses the in-tree make, not GNU Make, so
85[make(1)](https://man.freebsd.org/cgi/man.cgi?query=make&sektion=1) is another useful
86resource.
87
88The project uses mdoc for all its man pages. Changes should pass `mandoc -Tlint` and igor (install the latter with `pkg install igor`).
89Please be sure to observe the one-sentence-per-line rule so manual pages properly render. Any semantic changes to the manual pages should bump the date.
90[style.mdoc(5)](https://man.freebsd.org/cgi/man.cgi?query=style.mdoc&sektion=5) has the all details.
91
92For [Lua](https://www.lua.org), please see
93[style.lua(9)](https://man.freebsd.org/cgi/man.cgi?query=style.lua&sektion=9)
94for details. Lua is used for the boot loader and a few scripts in the base system.
95
96For shell scripts, avoid using bash. The system shell (/bin/sh) is preferred.
97Shell scripts in the base system cannot use bash or bash extensions
98not present in FreeBSD's [shell](https://man.freebsd.org/cgi/man.cgi?query=sh&sektion=1).
99
100## Signed-off-by
101
102Other projects use Signed-off-by to create a paper trail for contributions they
103receive. The Developer Certificate of Origin is an attestation that the person
104making the contribution can do it under the current license of the file. Other
105projects that have 'delegated' hierarchies also use it when maintainers
106integrate these patches and submit them upstream.
107
108Right now, pull requests on GitHub are an experimental feature. We strongly
109suggest that people add this line. It creates a paper trail for infrequent
110contributors. Also, developers that are landing a pull request will use a
111Signed-off-by line to set the author for the commit.
112
113These lines are easy to add with `git commit -s`.
114