xref: /freebsd/CONTRIBUTING.md (revision 2008043f386721d58158e37e0d7e50df8095942d)
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
11FreeBSD accepts source code contributions using one of several methods:
12- A GitHub [pull request](https://github.com/freebsd/freebsd-src/pulls)
13- A code review in [Phabricator](https://reviews.freebsd.org/differential)
14- An attachment on a [Bugzilla ticket](https://bugs.freebsd.org)
15- Direct access to the [Git repository](https://cgit.freebsd.org/src/)
16
17The preferred method depends on a few factors including the size or scope of
18the change.  GitHub pull requests are preferred for relatively straightforward
19changes where the contributor already has a GitHub account.
20
21## GitHub Pull Requests
22
23Presently, GitHub 'freebsd-src' repository is one of the publish-only services
24for the FreeBSD 'src' repository the project uses to promote collaboration and
25contribution.  Pull requests that need little developer time, are generally
26small, and have limited scope should be submitted. Do not submit pull requests
27that are security-related, problem reports, works in progress, changes that are controversial
28and need discussion, or changes that require specialized review.
29
30A pull request will be considered if:
31
32* 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.
33* It passes all the GitHub CI jobs.
34* You can respond to feedback quickly.
35* 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.
36* 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).
37* All commits have, as the author, your name and valid email address as you would like to see them in the FreeBSD repository. Fake github.com addresses cannot be used.
38* 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.
39* Fixup commits should be squashed with the commit they are fixing. Each commit in your branch should be suitable for FreeBSD's repository.
40* Commits should include one or more `Signed-off-by:` lines with full name and email address certifying [Developer Certificate of Origin](https://developercertificate.org/).
41* The commits follow FreeBSD's style guide. See [Style](#Style).
42* Run tools/build/checkstyle9.pl on your Git branch and eliminate all errors
43* The commits do not introduce trailing white space.
44* If the commmit fixes a bug, please add 'PR: \<bugnumber\>' to the commit message.
45* If there's a code review in Phabricator, please include a link as a 'Differential Revision: ' line.
46
47When updating your pull request, please rebase with a forced push rather than a
48merge commit.
49
50More complex changes may be submitted as pull requests, but they may be closed
51if they are too large, too unwieldy, become inactive, need further discussion in
52the community, or need extensive revision.  Please avoid creating large,
53wide-ranging cleanup patches: they are too large and lack the focus needed for a
54good review.  Misdirected patches may be redirected to a more appropriate forum
55for the patch to be resolved.
56
57Please make sure that your submissions compile and work before submitting. If
58you need feedback, a pull request might not be the right place (it may just be
59summarily closed if there are too many obvious mistakes).
60
61If you want to cleanup style or older coding conventions in preparation for some
62other commit, please go ahead and prepare those patches. However, please avoid just
63cleaning up to make it cleaner, unless there's a clear advantage to doing
64so. While the project strives to have a uniform coding style, our style offers a
65range of choices making some 'cleanups' ambiguous at best. Also, some files have
66their own consistent style that deviates from style(9). Style changes take
67volunteer time to process, but that time can be quite limited, so please be
68respectful.
69
70The current theory for pull requests on GitHub is to facilitate inclusion in the
71project. The guidelines are streamlined for quick decisions about each pull
72request. Unless explicitly stated, rejection here as "not ready" or "too large"
73does not mean the project is uninterested in the work, it just means the
74submission does not meet the limited scope for pull requests accepted
75here. Sometimes it is easier to review a GitHub pull request than to do the
76review in Phabricator, so that's also allowed.
77
78### Author Name and Email
79
80We require that contributions are associated with a unique identity.
81The author email address should not be `<something>@users.noreply.github.com`.
82Do note that your name and email address will become a permanent and immutable
83part of the public Git history of the FreeBSD source tree.
84
85## Style
86
87Avoid adding trailing newlines and whitespace. These slow down the integration
88process and are a distraction. `git diff` will highlight them in red, as will
89the Files Changed tab in the pull request.
90
91For C programs, see [style(9)](https://man.freebsd.org/cgi/man.cgi?query=style&sektion=9)
92for details. You can use [Clang format](https://clang.llvm.org/docs/ClangFormat.html)
93with the top level .clang-format file if you are unsure. The
94[git clang-format](https://github.com/llvm-mirror/clang/blob/master/tools/clang-format/git-clang-format)
95command can help minimize churn by only formatting the areas nearby the changes. While
96not perfect, using these tools will maximize your chances of not having style
97comments on your pull requests.
98
99For Makefiles changes, see
100[style.Makefile(5)](https://man.freebsd.org/cgi/man.cgi?query=style.Makefile&sektion=5)
101for details. FreeBSD's base system uses the in-tree make, not GNU Make, so
102[make(1)](https://man.freebsd.org/cgi/man.cgi?query=make&sektion=1) is another useful
103resource.
104
105The project uses mdoc for all its man pages. Changes should pass `mandoc -Tlint` and igor (install the latter with `pkg install igor`).
106Please 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.
107[style.mdoc(5)](https://man.freebsd.org/cgi/man.cgi?query=style.mdoc&sektion=5) has the all details.
108
109For [Lua](https://www.lua.org), please see
110[style.lua(9)](https://man.freebsd.org/cgi/man.cgi?query=style.lua&sektion=9)
111for details. Lua is used for the boot loader and a few scripts in the base system.
112
113For shell scripts, avoid using bash. The system shell (/bin/sh) is preferred.
114Shell scripts in the base system cannot use bash or bash extensions
115not present in FreeBSD's [shell](https://man.freebsd.org/cgi/man.cgi?query=sh&sektion=1).
116
117## Signed-off-by
118
119Other projects use Signed-off-by to create a paper trail for contributions they
120receive. The Developer Certificate of Origin is an attestation that the person
121making the contribution can do it under the current license of the file. Other
122projects that have 'delegated' hierarchies also use it when maintainers
123integrate these patches and submit them upstream.
124
125Right now, pull requests on GitHub are an experimental feature. We strongly
126suggest that people add this line. It creates a paper trail for infrequent
127contributors. Also, developers that are landing a pull request will use a
128Signed-off-by line to set the author for the commit.
129
130These lines are easy to add with `git commit -s`.
131