1 # LTTng-UST contributor's guide
3 Being an open source project, the LTTng-UST project welcomes
4 contributions from anyone. This guide walks you through the process
5 of contributing a patch to LTTng-UST.
8 ## Getting the source code
10 The LTTng-UST project uses [Git](https://git-scm.com/) for version
11 control. The upstream Git repository URL is:
13 git://git.lttng.org/lttng-ust.git
19 [Linux kernel coding style](http://www.kernel.org/doc/Documentation/CodingStyle).
21 Although the LTTng-UST code base is primarily written in C, it does
22 contain shell, Perl, and Python code as well. There is no official coding
23 standard for these languages. However, using a style consistent with the
24 rest of the code written in that language is strongly encouraged.
27 ## Creating and sending a patch
29 LTTng-UST's development flow is primarily email-based, although we
30 also accept pull requests on our
31 [GitHub mirror](https://github.com/lttng/lttng-ust). If you're going
32 to create GitHub pull requests, make sure you still follow the
35 Like a lot of open source projects, patches are submitted and reviewed
36 on its development mailing list,
37 [`lttng-dev`](http://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev)
38 (`lttng-dev@lists.lttng.org`). The mailing list is also used to share
39 and comment on <abbr title="Request for Comments">RFC</abbr>s and answer
42 Once your changes have been committed to your local branch, you may use
43 Git's [`format-patch`](https://git-scm.com/docs/git-format-patch) command
44 to generate a patch file. The following command line generates a
45 patch from the latest commit:
47 git format-patch -N1 -s --subject-prefix="PATCH lttng-ust"
49 The custom `PATCH lttng-ust` subject prefix is mandatory when
50 submitting patches that apply to the LTTng-UST project.
52 The patch's subject (the commit message's first line) should:
54 * begin with an uppercase letter
55 * be written in the present tense
56 * _not_ exceed 72 characters in length
57 * _not_ end with a period
58 * be prefixed with `Fix:` if the commit fixes a bug
60 The commit message's body should be as detailed as possible and explain
61 the reasons behind the proposed change. Any related
62 [bug report(s)](https://bugs.lttng.org/projects/lttng-ust/issues)
63 should be mentioned at the end of the message using the `#123` format,
64 where `123` is the bug number:
66 * Use `Refs: #123` if the patch is related to bug 123, but does not
68 * Use `Fixes: #123` to signify that this patch fixes the bug.
70 Make sure to **sign-off** your submitted patches (the `-s` argument to
71 Git's `commit` and `format-patch` commands).
73 Here's a complete example:
76 Fix: use this instead of that in some context
78 Ball tip jowl beef ribs shankle, leberkas venison turducken tail pork
79 chop t-bone meatball tri-tip. Tongue beef ribs corned beef ball tip
80 kevin ground round sausage rump meatloaf pig meatball prosciutto
81 landjaeger strip steak. Pork pork belly beef.
83 Biltong turkey porchetta filet mignon corned beef. T-bone bresaola
84 shoulder meatloaf tongue kielbasa.
90 Signed-off-by: Jeanne Mance <jmeance@lttng.org>
93 Please note that patches should be **as focused as possible**. Do not,
94 for instance, fix a bug and correct the indentation of an unrelated
95 block of code as part of the same patch.
97 Once you are confident your patch meets the required guidelines,
98 you may use Git's [`send-email`](https://git-scm.com/docs/git-send-email)
99 command to send your patch to the mailing list:
101 git send-email --suppress-cc=self --to lttng-dev@lists.lttng.org *.patch
104 [subscribed](http://lists.lttng.org/cgi-bin/mailman/listinfo/lttng-dev)
105 to the mailing list to follow and take part in discussions about your
106 changes. You may join the file to an email as an attachment if you can't
107 send the patch directly using <code>git send‑email</code>.
112 Once your patch has been posted to the mailing list or as a GitHub
113 pull request, other contributors may propose modifications.
114 This is completely normal. This collaborative code review is an integral
115 part of the open source development process in general and LTTng-UST
118 Keep in mind that reviewing patches is a time-consuming process and,
119 as such, may not be done right away. The delays may be affected by the
120 current release cycle phase and the complexity of the proposed changes.
121 If you think your patch might have been forgotten, please mention it on
122 the [`#lttng`](irc://irc.oftc.net/lttng) IRC channel rather than
128 The LTTng-UST project follows a release cycle that alternates between
129 development and release candidate (RC) phases. The master branch is
130 feature-frozen during RC phases: only bug fixes are accepted during
131 this period. However, patches adding new functionality may still be
132 submitted and reviewed during the RC. The upcoming features and release
133 dates are posted in a monthly digest on the mailing list.