# Contributing to GNSS-SDR

:+1::tada: Thanks for taking the time to contribute! :tada::+1:

Third-party contributions are essential for keeping GNSS-SDR
continuously improving. We simply cannot access the huge number of
platforms and myriad configurations for running GNSS-SDR. We want to
keep it as easy as possible to contribute changes that get things
working in your environment. There are a few guidelines that we need
contributors to follow so that we can have a chance of keeping on top of
things.

The following is a set of guidelines for contributing to GNSS-SDR, which
is hosted in the [GNSS-SDR Organization](https://github.com/gnss-sdr) on
GitHub. These are just guidelines, not rules. Use your best judgment,
and feel free to propose changes to this document in a [pull
request](#how-to-submit-a-pull-request).

## Code of Conduct

This project adheres to the Contributor Covenant [code of
conduct](CODE_OF_CONDUCT.md). By participating, you are expected to
uphold this code. Please report unacceptable behavior.

## Reporting an issue

Have you found a bug in the code which is not in the [list of known
bugs](https://github.com/gnss-sdr/gnss-sdr/issues)? Do you have a
suggestion for improvement? Then by all means please [submit a new
issue](https://github.com/gnss-sdr/gnss-sdr/issues/new), and do not
hesitate to comment on existing [open
issues](https://github.com/gnss-sdr/gnss-sdr/issues).

When filling a new issue, please remember to:

 * **Use a clear and descriptive title** for the issue to identify the
problem.

 * **Describe the exact steps which reproduce the problem** in as many
details as possible. For example, start by describing your computing
platform (Operating System and version, how did you installed GNSS-SDR
and its dependencies, what file or front-end are you using as a signal
source, etc.). You can also include the configuration file you are
using, or a dump of the terminal output you are getting. The more
information you provide, the more chances to get useful answers.

 * **Please be patient**. This organization is run on a volunteer basis,
so it can take some time to the Developer Team to reach your issue.
They will do their best to fix it as soon as possible.

 * If you opened an issue that is now solved, it is a good practice to
**close it**.

The list of [open issues](https://github.com/gnss-sdr/gnss-sdr/issues)
can be a good starting point and a source of ideas if you are looking to
contribute to the source code.


## Contributing to the source code

### Preliminaries

   1. If you still have not done so, [create your personal account on
GitHub](https://github.com/join).

   2. [Fork GNSS-SDR from
GitHub](https://github.com/gnss-sdr/gnss-sdr/fork). This will copy the
whole gnss-sdr repository to your personal account.

   3. Then, go to your favorite working folder in your computer and
clone your forked repository by typing (replacing ```YOUR_USERNAME``` by
the actual username of your GitHub account):

          $ git clone https://github.com/YOUR_USERNAME/gnss-sdr

   4. Your forked repository https://github.com/YOUR_USERNAME/gnss-sdr
will receive the default name of `origin`. You can also add the original
gnss-sdr repository, which is usually called `upstream`:

          $ cd gnss-sdr
          $ git remote add upstream https://github.com/gnss-sdr/gnss-sdr.git

To verify the new upstream repository you have specified for your fork,
type `git remote -v`. You should see the URL for your fork as `origin`,
and the URL for the original repository as `upstream`:

```
$ git remote -v
origin    https://github.com/YOUR_USERNAME/gnss-sdr.git (fetch)
origin    https://github.com/YOUR_USERNAME/gnss-sdr.git (push)
upstream  https://github.com/gnss-sdr/gnss-sdr.git (fetch)
upstream  https://github.com/gnss-sdr/gnss-sdr.git (push)
```

### Start working on your contribution

Checkout the `next` branch of the git repository in order to get
synchronized with the latest development code:

```
$ git checkout next
$ git pull upstream next
```

When start working in a new improvement, please **always** branch off
from `next`. Open a new branch and start working on it:

```
$ git checkout -b my_feature
```

Now you can do changes, add files, do commits (please take a look at
[how to write good commit
messages](https://chris.beams.io/posts/git-commit/)!) and push them to
your repository:

```
$ git push origin my_feature
```

If there have been new pushes to the `next` branch of the `upstream`
repository since the last time you pulled from it, you might want to put
your commits on top of them (this is mandatory for pull requests):

```
$ git pull --rebase upstream next
```

### How to submit a pull request

Before submitting your code, please be sure to [apply clang-format](http://gnss-sdr.org/coding-style/#use-tools-for-automated-code-formatting).

When the contribution is ready, you can [submit a pull
request](https://github.com/gnss-sdr/gnss-sdr/compare/). Head to your
GitHub repository, switch to your `my_feature` branch, and click the
_**Pull Request**_ button, which will do all the work for you. Code
comparison must be always to the `next` branch.

Once a pull request is sent, the Developer Team can review the set of
changes, discuss potential modifications, and even push follow-up
commits if necessary.

Some things that will increase the chance that your pull request is
accepted:

 * Avoid platform-dependent code. If your code require external
 dependencies, they must be available as packages in [Debian OldStable](https://wiki.debian.org/DebianOldStable).
 * Write tests.
 * Follow our [coding style guide](http://gnss-sdr.org/coding-style/).
 * Write a descriptive and detailed summary. Please consider that
reviewing pull requests is hard, so include as much information as
possible to make your pull request's intent clear.

For more details about Git usage, please check out [our
tutorial](http://gnss-sdr.org/docs/tutorials/using-git/).


## Contributing to the website

The content of http://gnss-sdr.org lives in a GitHub repository at
https://github.com/gnss-sdr/geniuss-place

You can fork that repository, reproduce the entire website on your
computer using [Jekyll](https://jekyllrb.com/), do changes and submit
pull requests, just as explained above. For more details, please check
out [how to contribute](http://gnss-sdr.org/contribute/).

Last but not the least, you can leave your comments on the website.


------



![GeNiuSS
contributes](http://gnss-sdr.org/assets/images/geniuss-contribute.png)

Thanks for your contribution to GNSS-SDR!
