# Contributing to Yosys SymbiFlow Plugins

There are a couple of guidelines when contributing to Yosys SymbiFlow Plugins
which are listed here.

### Sending

All contributions should be sent as
[GitHub Pull requests](https://help.github.com/articles/creating-a-pull-request-from-a-fork/).

### License

All software (code, associated documentation, support files, etc) in the
Yosys SymbiFlow Plugins repository are licensed under the very permissive
[ISC Licence](COPYING). A copy can be found in the [`COPYING`](COPYING) file.

All new contributions must also be released under this license.

### Code of Conduct

By contributing you agree to the [code of conduct](CODE_OF_CONDUCT.md). We
follow the open source best practice of using the [Contributor
Covenant](https://www.contributor-covenant.org/) for our Code of Conduct.

### Sign your work

To improve tracking of who did what, we follow the Linux Kernel's
["sign your work" system](https://github.com/wking/signed-off-by).
This is also called a
["DCO" or "Developer's Certificate of Origin"](https://developercertificate.org/).

**All** commits are required to include this sign off and we use the
[Probot DCO App](https://github.com/probot/dco) to check pull requests for
this.

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>

using your real name (sorry, no pseudonyms or anonymous contributions.)

You can add the signoff as part of your commit statement. For example:

    git commit --signoff -a -m "Fixed some errors."

*Hint:* If you've forgotten to add a signoff to one or more commits, you can use the
following command to add signoffs to all commits between you and the upstream
master:

    git rebase --signoff upstream/master