xref: /openbmc/u-boot/tools/patman/README (revision c68c03f5)
1# Copyright (c) 2011 The Chromium OS Authors.
2#
3# SPDX-License-Identifier:	GPL-2.0+
4#
5
6What is this?
7=============
8
9This tool is a Python script which:
10- Creates patch directly from your branch
11- Cleans them up by removing unwanted tags
12- Inserts a cover letter with change lists
13- Runs the patches through checkpatch.pl and its own checks
14- Optionally emails them out to selected people
15
16It is intended to automate patch creation and make it a less
17error-prone process. It is useful for U-Boot and Linux work so far,
18since it uses the checkpatch.pl script.
19
20It is configured almost entirely by tags it finds in your commits.
21This means that you can work on a number of different branches at
22once, and keep the settings with each branch rather than having to
23git format-patch, git send-email, etc. with the correct parameters
24each time. So for example if you put:
25
26Series-to: fred.blogs@napier.co.nz
27
28in one of your commits, the series will be sent there.
29
30In Linux and U-Boot this will also call get_maintainer.pl on each of your
31patches automatically (unless you use -m to disable this).
32
33
34How to use this tool
35====================
36
37This tool requires a certain way of working:
38
39- Maintain a number of branches, one for each patch series you are
40working on
41- Add tags into the commits within each branch to indicate where the
42series should be sent, cover letter, version, etc. Most of these are
43normally in the top commit so it is easy to change them with 'git
44commit --amend'
45- Each branch tracks the upstream branch, so that this script can
46automatically determine the number of commits in it (optional)
47- Check out a branch, and run this script to create and send out your
48patches. Weeks later, change the patches and repeat, knowing that you
49will get a consistent result each time.
50
51
52How to configure it
53===================
54
55For most cases of using patman for U-Boot development, patman can use the
56file 'doc/git-mailrc' in your U-Boot directory to supply the email aliases
57you need. To make this work, tell git where to find the file by typing
58this once:
59
60    git config sendemail.aliasesfile doc/git-mailrc
61
62For both Linux and U-Boot the 'scripts/get_maintainer.pl' handles figuring
63out where to send patches pretty well.
64
65During the first run patman creates a config file for you by taking the default
66user name and email address from the global .gitconfig file.
67
68To add your own, create a file ~/.patman like this:
69
70>>>>
71# patman alias file
72
73[alias]
74me: Simon Glass <sjg@chromium.org>
75
76u-boot: U-Boot Mailing List <u-boot@lists.denx.de>
77wolfgang: Wolfgang Denk <wd@denx.de>
78others: Mike Frysinger <vapier@gentoo.org>, Fred Bloggs <f.bloggs@napier.net>
79
80<<<<
81
82Aliases are recursive.
83
84The checkpatch.pl in the U-Boot tools/ subdirectory will be located and
85used. Failing that you can put it into your path or ~/bin/checkpatch.pl
86
87If you want to avoid sending patches to email addresses that are picked up
88by patman but are known to bounce you can add a [bounces] section to your
89.patman file. Unlike the [alias] section these are simple key: value pairs
90that are not recursive.
91
92>>>
93
94[bounces]
95gonefishing: Fred Bloggs <f.bloggs@napier.net>
96
97<<<
98
99
100If you want to change the defaults for patman's command-line arguments,
101you can add a [settings] section to your .patman file.  This can be used
102for any command line option by referring to the "dest" for the option in
103patman.py.  For reference, the useful ones (at the moment) shown below
104(all with the non-default setting):
105
106>>>
107
108[settings]
109ignore_errors: True
110process_tags: False
111verbose: True
112
113<<<
114
115
116If you want to adjust settings (or aliases) that affect just a single
117project you can add a section that looks like [project_settings] or
118[project_alias].  If you want to use tags for your linux work, you could
119do:
120
121>>>
122
123[linux_settings]
124process_tags: True
125
126<<<
127
128
129How to run it
130=============
131
132First do a dry run:
133
134$ ./tools/patman/patman -n
135
136If it can't detect the upstream branch, try telling it how many patches
137there are in your series:
138
139$ ./tools/patman/patman -n -c5
140
141This will create patch files in your current directory and tell you who
142it is thinking of sending them to. Take a look at the patch files.
143
144$ ./tools/patman/patman -n -c5 -s1
145
146Similar to the above, but skip the first commit and take the next 5. This
147is useful if your top commit is for setting up testing.
148
149
150How to install it
151=================
152
153The most up to date version of patman can be found in the U-Boot sources.
154However to use it on other projects it may be more convenient to install it as
155a standalone application. A distutils installer is included, this can be used
156to install patman:
157
158$ cd tools/patman && python setup.py install
159
160
161How to add tags
162===============
163
164To make this script useful you must add tags like the following into any
165commit. Most can only appear once in the whole series.
166
167Series-to: email / alias
168	Email address / alias to send patch series to (you can add this
169	multiple times)
170
171Series-cc: email / alias, ...
172	Email address / alias to Cc patch series to (you can add this
173	multiple times)
174
175Series-version: n
176	Sets the version number of this patch series
177
178Series-prefix: prefix
179	Sets the subject prefix. Normally empty but it can be RFC for
180	RFC patches, or RESEND if you are being ignored. The patch subject
181	is like [RFC PATCH] or [RESEND PATCH].
182	In the meantime, git format.subjectprefix option will be added as
183	well. If your format.subjectprefix is set to InternalProject, then
184	the patch shows like: [InternalProject][RFC/RESEND PATCH]
185
186Series-name: name
187	Sets the name of the series. You don't need to have a name, and
188	patman does not yet use it, but it is convenient to put the branch
189	name here to help you keep track of multiple upstreaming efforts.
190
191Cover-letter:
192This is the patch set title
193blah blah
194more blah blah
195END
196	Sets the cover letter contents for the series. The first line
197	will become the subject of the cover letter
198
199Cover-letter-cc: email / alias
200	Additional email addresses / aliases to send cover letter to (you
201	can add this multiple times)
202
203Series-notes:
204blah blah
205blah blah
206more blah blah
207END
208	Sets some notes for the patch series, which you don't want in
209	the commit messages, but do want to send, The notes are joined
210	together and put after the cover letter. Can appear multiple
211	times.
212
213Commit-notes:
214blah blah
215blah blah
216more blah blah
217END
218	Similar, but for a single commit (patch). These notes will appear
219	immediately below the --- cut in the patch file.
220
221 Signed-off-by: Their Name <email>
222	A sign-off is added automatically to your patches (this is
223	probably a bug). If you put this tag in your patches, it will
224	override the default signoff that patman automatically adds.
225	Multiple duplicate signoffs will be removed.
226
227 Tested-by: Their Name <email>
228 Reviewed-by: Their Name <email>
229 Acked-by: Their Name <email>
230	These indicate that someone has tested/reviewed/acked your patch.
231	When you get this reply on the mailing list, you can add this
232	tag to the relevant commit and the script will include it when
233	you send out the next version. If 'Tested-by:' is set to
234	yourself, it will be removed. No one will believe you.
235
236Series-changes: n
237- Guinea pig moved into its cage
238- Other changes ending with a blank line
239<blank line>
240	This can appear in any commit. It lists the changes for a
241	particular version n of that commit. The change list is
242	created based on this information. Each commit gets its own
243	change list and also the whole thing is repeated in the cover
244	letter (where duplicate change lines are merged).
245
246	By adding your change lists into your commits it is easier to
247	keep track of what happened. When you amend a commit, remember
248	to update the log there and then, knowing that the script will
249	do the rest.
250
251Patch-cc: Their Name <email>
252	This copies a single patch to another email address. Note that the
253	Cc: used by git send-email is ignored by patman, but will be
254	interpreted by git send-email if you use it.
255
256Series-process-log: sort, uniq
257	This tells patman to sort and/or uniq the change logs. It is
258	assumed that each change log entry is only a single line long.
259	Use 'sort' to sort the entries, and 'uniq' to include only
260	unique entries. If omitted, no change log processing is done.
261	Separate each tag with a comma.
262
263Various other tags are silently removed, like these Chrome OS and
264Gerrit tags:
265
266BUG=...
267TEST=...
268Change-Id:
269Review URL:
270Reviewed-on:
271Commit-xxxx: (except Commit-notes)
272
273Exercise for the reader: Try adding some tags to one of your current
274patch series and see how the patches turn out.
275
276
277Where Patches Are Sent
278======================
279
280Once the patches are created, patman sends them using git send-email. The
281whole series is sent to the recipients in Series-to: and Series-cc.
282You can Cc individual patches to other people with the Patch-cc: tag. Tags
283in the subject are also picked up to Cc patches. For example, a commit like
284this:
285
286>>>>
287commit 10212537b85ff9b6e09c82045127522c0f0db981
288Author: Mike Frysinger <vapier@gentoo.org>
289Date:	Mon Nov 7 23:18:44 2011 -0500
290
291    x86: arm: add a git mailrc file for maintainers
292
293    This should make sending out e-mails to the right people easier.
294
295    Patch-cc: sandbox, mikef, ag
296    Patch-cc: afleming
297<<<<
298
299will create a patch which is copied to x86, arm, sandbox, mikef, ag and
300afleming.
301
302If you have a cover letter it will get sent to the union of the Patch-cc
303lists of all of the other patches. If you want to sent it to additional
304people you can add a tag:
305
306Cover-letter-cc: <list of addresses>
307
308These people will get the cover letter even if they are not on the To/Cc
309list for any of the patches.
310
311
312Example Work Flow
313=================
314
315The basic workflow is to create your commits, add some tags to the top
316commit, and type 'patman' to check and send them.
317
318Here is an example workflow for a series of 4 patches. Let's say you have
319these rather contrived patches in the following order in branch us-cmd in
320your tree where 'us' means your upstreaming activity (newest to oldest as
321output by git log --oneline):
322
323    7c7909c wip
324    89234f5 Don't include standard parser if hush is used
325    8d640a7 mmc: sparc: Stop using builtin_run_command()
326    0c859a9 Rename run_command2() to run_command()
327    a74443f sandbox: Rename run_command() to builtin_run_command()
328
329The first patch is some test things that enable your code to be compiled,
330but that you don't want to submit because there is an existing patch for it
331on the list. So you can tell patman to create and check some patches
332(skipping the first patch) with:
333
334    patman -s1 -n
335
336If you want to do all of them including the work-in-progress one, then
337(if you are tracking an upstream branch):
338
339    patman -n
340
341Let's say that patman reports an error in the second patch. Then:
342
343    git rebase -i HEAD~6
344    <change 'pick' to 'edit' in 89234f5>
345    <use editor to make code changes>
346    git add -u
347    git rebase --continue
348
349Now you have an updated patch series. To check it:
350
351    patman -s1 -n
352
353Let's say it is now clean and you want to send it. Now you need to set up
354the destination. So amend the top commit with:
355
356    git commit --amend
357
358Use your editor to add some tags, so that the whole commit message is:
359
360    The current run_command() is really only one of the options, with
361    hush providing the other. It really shouldn't be called directly
362    in case the hush parser is bring used, so rename this function to
363    better explain its purpose.
364
365    Series-to: u-boot
366    Series-cc: bfin, marex
367    Series-prefix: RFC
368    Cover-letter:
369    Unified command execution in one place
370
371    At present two parsers have similar code to execute commands. Also
372    cmd_usage() is called all over the place. This series adds a single
373    function which processes commands called cmd_process().
374    END
375
376    Change-Id: Ica71a14c1f0ecb5650f771a32fecb8d2eb9d8a17
377
378
379You want this to be an RFC and Cc the whole series to the bfin alias and
380to Marek. Two of the patches have tags (those are the bits at the front of
381the subject that say mmc: sparc: and sandbox:), so 8d640a7 will be Cc'd to
382mmc and sparc, and the last one to sandbox.
383
384Now to send the patches, take off the -n flag:
385
386   patman -s1
387
388The patches will be created, shown in your editor, and then sent along with
389the cover letter. Note that patman's tags are automatically removed so that
390people on the list don't see your secret info.
391
392Of course patches often attract comments and you need to make some updates.
393Let's say one person sent comments and you get an Acked-by: on one patch.
394Also, the patch on the list that you were waiting for has been merged,
395so you can drop your wip commit. So you resync with upstream:
396
397    git fetch origin		(or whatever upstream is called)
398    git rebase origin/master
399
400and use git rebase -i to edit the commits, dropping the wip one. You add
401the ack tag to one commit:
402
403    Acked-by: Heiko Schocher <hs@denx.de>
404
405update the Series-cc: in the top commit:
406
407    Series-cc: bfin, marex, Heiko Schocher <hs@denx.de>
408
409and remove the Series-prefix: tag since it it isn't an RFC any more. The
410series is now version two, so the series info in the top commit looks like
411this:
412
413    Series-to: u-boot
414    Series-cc: bfin, marex, Heiko Schocher <hs@denx.de>
415    Series-version: 2
416    Cover-letter:
417    ...
418
419Finally, you need to add a change log to the two commits you changed. You
420add change logs to each individual commit where the changes happened, like
421this:
422
423    Series-changes: 2
424    - Updated the command decoder to reduce code size
425    - Wound the torque propounder up a little more
426
427(note the blank line at the end of the list)
428
429When you run patman it will collect all the change logs from the different
430commits and combine them into the cover letter, if you have one. So finally
431you have a new series of commits:
432
433    faeb973 Don't include standard parser if hush is used
434    1b2f2fe mmc: sparc: Stop using builtin_run_command()
435    cfbe330 Rename run_command2() to run_command()
436    0682677 sandbox: Rename run_command() to builtin_run_command()
437
438so to send them:
439
440    patman
441
442and it will create and send the version 2 series.
443
444General points:
445
4461. When you change back to the us-cmd branch days or weeks later all your
447information is still there, safely stored in the commits. You don't need
448to remember what version you are up to, who you sent the last lot of patches
449to, or anything about the change logs.
450
4512. If you put tags in the subject, patman will Cc the maintainers
452automatically in many cases.
453
4543. If you want to keep the commits from each series you sent so that you can
455compare change and see what you did, you can either create a new branch for
456each version, or just tag the branch before you start changing it:
457
458    git tag sent/us-cmd-rfc
459    ...later...
460    git tag sent/us-cmd-v2
461
4624. If you want to modify the patches a little before sending, you can do
463this in your editor, but be careful!
464
4655. If you want to run git send-email yourself, use the -n flag which will
466print out the command line patman would have used.
467
4686. It is a good idea to add the change log info as you change the commit,
469not later when you can't remember which patch you changed. You can always
470go back and change or remove logs from commits.
471
472
473Other thoughts
474==============
475
476This script has been split into sensible files but still needs work.
477Most of these are indicated by a TODO in the code.
478
479It would be nice if this could handle the In-reply-to side of things.
480
481The tests are incomplete, as is customary. Use the --test flag to run them,
482and make sure you are in the tools/patman directory first:
483
484    $ cd /path/to/u-boot
485    $ cd tools/patman
486    $ ./patman --test
487
488Error handling doesn't always produce friendly error messages - e.g.
489putting an incorrect tag in a commit may provide a confusing message.
490
491There might be a few other features not mentioned in this README. They
492might be bugs. In particular, tags are case sensitive which is probably
493a bad thing.
494
495
496Simon Glass <sjg@chromium.org>
497v1, v2, 19-Oct-11
498revised v3 24-Nov-11
499