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diff --git a/Documentation/SubmittingPatches b/Documentation/SubmittingPatches new file mode 100644 index 0000000000..0e155c936c --- /dev/null +++ b/Documentation/SubmittingPatches @@ -0,0 +1,453 @@ +Checklist (and a short version for the impatient): + + Commits: + + - make commits of logical units + - check for unnecessary whitespace with "git diff --check" + before committing + - do not check in commented out code or unneeded files + - provide a meaningful commit message + - the first line of the commit message should be a short + description and should skip the full stop + - if you want your work included in git.git, add a + "Signed-off-by: Your Name <you@example.com>" line to the + commit message (or just use the option "-s" when + committing) to confirm that you agree to the Developer's + Certificate of Origin + - make sure that you have tests for the bug you are fixing + - make sure that the test suite passes after your commit + + Patch: + + - use "git format-patch -M" to create the patch + - do not PGP sign your patch + - do not attach your patch, but read in the mail + body, unless you cannot teach your mailer to + leave the formatting of the patch alone. + - be careful doing cut & paste into your mailer, not to + corrupt whitespaces. + - provide additional information (which is unsuitable for + the commit message) between the "---" and the diffstat + - if you change, add, or remove a command line option or + make some other user interface change, the associated + documentation should be updated as well. + - if your name is not writable in ASCII, make sure that + you send off a message in the correct encoding. + - send the patch to the list (git@vger.kernel.org) and the + maintainer (gitster@pobox.com) if (and only if) the patch + is ready for inclusion. If you use git-send-email(1), + please test it first by sending email to yourself. + +Long version: + +I started reading over the SubmittingPatches document for Linux +kernel, primarily because I wanted to have a document similar to +it for the core GIT to make sure people understand what they are +doing when they write "Signed-off-by" line. + +But the patch submission requirements are a lot more relaxed +here on the technical/contents front, because the core GIT is +thousand times smaller ;-). So here is only the relevant bits. + + +(1) Make separate commits for logically separate changes. + +Unless your patch is really trivial, you should not be sending +out a patch that was generated between your working tree and +your commit head. Instead, always make a commit with complete +commit message and generate a series of patches from your +repository. It is a good discipline. + +Describe the technical detail of the change(s). + +If your description starts to get too long, that's a sign that you +probably need to split up your commit to finer grained pieces. + +Oh, another thing. I am picky about whitespaces. Make sure your +changes do not trigger errors with the sample pre-commit hook shipped +in templates/hooks--pre-commit. To help ensure this does not happen, +run git diff --check on your changes before you commit. + + +(1a) Try to be nice to older C compilers + +We try to support wide range of C compilers to compile +git with. That means that you should not use C99 initializers, even +if a lot of compilers grok it. + +Also, variables have to be declared at the beginning of the block +(you can check this with gcc, using the -Wdeclaration-after-statement +option). + +Another thing: NULL pointers shall be written as NULL, not as 0. + + +(2) Generate your patch using git tools out of your commits. + +git based diff tools (git, Cogito, and StGIT included) generate +unidiff which is the preferred format. + +You do not have to be afraid to use -M option to "git diff" or +"git format-patch", if your patch involves file renames. The +receiving end can handle them just fine. + +Please make sure your patch does not include any extra files +which do not belong in a patch submission. Make sure to review +your patch after generating it, to ensure accuracy. Before +sending out, please make sure it cleanly applies to the "master" +branch head. If you are preparing a work based on "next" branch, +that is fine, but please mark it as such. + + +(3) Sending your patches. + +People on the git mailing list need to be able to read and +comment on the changes you are submitting. It is important for +a developer to be able to "quote" your changes, using standard +e-mail tools, so that they may comment on specific portions of +your code. For this reason, all patches should be submitted +"inline". WARNING: Be wary of your MUAs word-wrap +corrupting your patch. Do not cut-n-paste your patch; you can +lose tabs that way if you are not careful. + +It is a common convention to prefix your subject line with +[PATCH]. This lets people easily distinguish patches from other +e-mail discussions. Use of additional markers after PATCH and +the closing bracket to mark the nature of the patch is also +encouraged. E.g. [PATCH/RFC] is often used when the patch is +not ready to be applied but it is for discussion, [PATCH v2], +[PATCH v3] etc. are often seen when you are sending an update to +what you have previously sent. + +"git format-patch" command follows the best current practice to +format the body of an e-mail message. At the beginning of the +patch should come your commit message, ending with the +Signed-off-by: lines, and a line that consists of three dashes, +followed by the diffstat information and the patch itself. If +you are forwarding a patch from somebody else, optionally, at +the beginning of the e-mail message just before the commit +message starts, you can put a "From: " line to name that person. + +You often want to add additional explanation about the patch, +other than the commit message itself. Place such "cover letter" +material between the three dash lines and the diffstat. + +Do not attach the patch as a MIME attachment, compressed or not. +Do not let your e-mail client send quoted-printable. Do not let +your e-mail client send format=flowed which would destroy +whitespaces in your patches. Many +popular e-mail applications will not always transmit a MIME +attachment as plain text, making it impossible to comment on +your code. A MIME attachment also takes a bit more time to +process. This does not decrease the likelihood of your +MIME-attached change being accepted, but it makes it more likely +that it will be postponed. + +Exception: If your mailer is mangling patches then someone may ask +you to re-send them using MIME, that is OK. + +Do not PGP sign your patch, at least for now. Most likely, your +maintainer or other people on the list would not have your PGP +key and would not bother obtaining it anyway. Your patch is not +judged by who you are; a good patch from an unknown origin has a +far better chance of being accepted than a patch from a known, +respected origin that is done poorly or does incorrect things. + +If you really really really really want to do a PGP signed +patch, format it as "multipart/signed", not a text/plain message +that starts with '-----BEGIN PGP SIGNED MESSAGE-----'. That is +not a text/plain, it's something else. + +Note that your maintainer does not necessarily read everything +on the git mailing list. If your patch is for discussion first, +send it "To:" the mailing list, and optionally "cc:" him. If it +is trivially correct or after the list reached a consensus, send +it "To:" the maintainer and optionally "cc:" the list for +inclusion. + +Also note that your maintainer does not actively involve himself in +maintaining what are in contrib/ hierarchy. When you send fixes and +enhancements to them, do not forget to "cc: " the person who primarily +worked on that hierarchy in contrib/. + + +(4) Sign your work + +To improve tracking of who did what, we've borrowed the +"sign-off" procedure from the Linux kernel project on patches +that are being emailed around. Although core GIT is a lot +smaller project it is a good discipline to follow it. + +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 a open-source patch. The rules are +pretty simple: if you can certify the below: + + Developer's Certificate of Origin 1.1 + + 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. + +then you just add a line saying + + Signed-off-by: Random J Developer <random@developer.example.org> + +This line can be automatically added by git if you run the git-commit +command with the -s option. + +Notice that you can place your own Signed-off-by: line when +forwarding somebody else's patch with the above rules for +D-C-O. Indeed you are encouraged to do so. Do not forget to +place an in-body "From: " line at the beginning to properly attribute +the change to its true author (see (2) above). + +Some people also put extra tags at the end. + +"Acked-by:" says that the patch was reviewed by the person who +is more familiar with the issues and the area the patch attempts +to modify. "Tested-by:" says the patch was tested by the person +and found to have the desired effect. + +------------------------------------------------ +An ideal patch flow + +Here is an ideal patch flow for this project the current maintainer +suggests to the contributors: + + (0) You come up with an itch. You code it up. + + (1) Send it to the list and cc people who may need to know about + the change. + + The people who may need to know are the ones whose code you + are butchering. These people happen to be the ones who are + most likely to be knowledgeable enough to help you, but + they have no obligation to help you (i.e. you ask for help, + don't demand). "git log -p -- $area_you_are_modifying" would + help you find out who they are. + + (2) You get comments and suggestions for improvements. You may + even get them in a "on top of your change" patch form. + + (3) Polish, refine, and re-send to the list and the people who + spend their time to improve your patch. Go back to step (2). + + (4) The list forms consensus that the last round of your patch is + good. Send it to the list and cc the maintainer. + + (5) A topic branch is created with the patch and is merged to 'next', + and cooked further and eventually graduates to 'master'. + +In any time between the (2)-(3) cycle, the maintainer may pick it up +from the list and queue it to 'pu', in order to make it easier for +people play with it without having to pick up and apply the patch to +their trees themselves. + +------------------------------------------------ +MUA specific hints + +Some of patches I receive or pick up from the list share common +patterns of breakage. Please make sure your MUA is set up +properly not to corrupt whitespaces. Here are two common ones +I have seen: + +* Empty context lines that do not have _any_ whitespace. + +* Non empty context lines that have one extra whitespace at the + beginning. + +One test you could do yourself if your MUA is set up correctly is: + +* Send the patch to yourself, exactly the way you would, except + To: and Cc: lines, which would not contain the list and + maintainer address. + +* Save that patch to a file in UNIX mailbox format. Call it say + a.patch. + +* Try to apply to the tip of the "master" branch from the + git.git public repository: + + $ git fetch http://kernel.org/pub/scm/git/git.git master:test-apply + $ git checkout test-apply + $ git reset --hard + $ git am a.patch + +If it does not apply correctly, there can be various reasons. + +* Your patch itself does not apply cleanly. That is _bad_ but + does not have much to do with your MUA. Please rebase the + patch appropriately. + +* Your MUA corrupted your patch; "am" would complain that + the patch does not apply. Look at .dotest/ subdirectory and + see what 'patch' file contains and check for the common + corruption patterns mentioned above. + +* While you are at it, check what are in 'info' and + 'final-commit' files as well. If what is in 'final-commit' is + not exactly what you would want to see in the commit log + message, it is very likely that your maintainer would end up + hand editing the log message when he applies your patch. + Things like "Hi, this is my first patch.\n", if you really + want to put in the patch e-mail, should come after the + three-dash line that signals the end of the commit message. + + +Pine +---- + +(Johannes Schindelin) + +I don't know how many people still use pine, but for those poor +souls it may be good to mention that the quell-flowed-text is +needed for recent versions. + +... the "no-strip-whitespace-before-send" option, too. AFAIK it +was introduced in 4.60. + +(Linus Torvalds) + +And 4.58 needs at least this. + +--- +diff-tree 8326dd8350be64ac7fc805f6563a1d61ad10d32c (from e886a61f76edf5410573e92e38ce22974f9c40f1) +Author: Linus Torvalds <torvalds@g5.osdl.org> +Date: Mon Aug 15 17:23:51 2005 -0700 + + Fix pine whitespace-corruption bug + + There's no excuse for unconditionally removing whitespace from + the pico buffers on close. + +diff --git a/pico/pico.c b/pico/pico.c +--- a/pico/pico.c ++++ b/pico/pico.c +@@ -219,7 +219,9 @@ PICO *pm; + switch(pico_all_done){ /* prepare for/handle final events */ + case COMP_EXIT : /* already confirmed */ + packheader(); ++#if 0 + stripwhitespace(); ++#endif + c |= COMP_EXIT; + break; + + +(Daniel Barkalow) + +> A patch to SubmittingPatches, MUA specific help section for +> users of Pine 4.63 would be very much appreciated. + +Ah, it looks like a recent version changed the default behavior to do the +right thing, and inverted the sense of the configuration option. (Either +that or Gentoo did it.) So you need to set the +"no-strip-whitespace-before-send" option, unless the option you have is +"strip-whitespace-before-send", in which case you should avoid checking +it. + + +Thunderbird +----------- + +(A Large Angry SCM) + +Here are some hints on how to successfully submit patches inline using +Thunderbird. + +This recipe appears to work with the current [*1*] Thunderbird from Suse. + +The following Thunderbird extensions are needed: + AboutConfig 0.5 + http://aboutconfig.mozdev.org/ + External Editor 0.7.2 + http://globs.org/articles.php?lng=en&pg=8 + +1) Prepare the patch as a text file using your method of choice. + +2) Before opening a compose window, use Edit->Account Settings to +uncheck the "Compose messages in HTML format" setting in the +"Composition & Addressing" panel of the account to be used to send the +patch. [*2*] + +3) In the main Thunderbird window, _before_ you open the compose window +for the patch, use Tools->about:config to set the following to the +indicated values: + mailnews.send_plaintext_flowed => false + mailnews.wraplength => 0 + +4) Open a compose window and click the external editor icon. + +5) In the external editor window, read in the patch file and exit the +editor normally. + +6) Back in the compose window: Add whatever other text you wish to the +message, complete the addressing and subject fields, and press send. + +7) Optionally, undo the about:config/account settings changes made in +steps 2 & 3. + + +[Footnotes] +*1* Version 1.0 (20041207) from the MozillaThunderbird-1.0-5 rpm of Suse +9.3 professional updates. + +*2* It may be possible to do this with about:config and the following +settings but I haven't tried, yet. + mail.html_compose => false + mail.identity.default.compose_html => false + mail.identity.id?.compose_html => false + + +Gnus +---- + +'|' in the *Summary* buffer can be used to pipe the current +message to an external program, and this is a handy way to drive +"git am". However, if the message is MIME encoded, what is +piped into the program is the representation you see in your +*Article* buffer after unwrapping MIME. This is often not what +you would want for two reasons. It tends to screw up non ASCII +characters (most notably in people's names), and also +whitespaces (fatal in patches). Running 'C-u g' to display the +message in raw form before using '|' to run the pipe can work +this problem around. + + +KMail +----- + +This should help you to submit patches inline using KMail. + +1) Prepare the patch as a text file. + +2) Click on New Mail. + +3) Go under "Options" in the Composer window and be sure that +"Word wrap" is not set. + +4) Use Message -> Insert file... and insert the patch. + +5) Back in the compose window: add whatever other text you wish to the +message, complete the addressing and subject fields, and press send. |