Purism-Calls/HACKING.md

3.6 KiB

Building

For build instructions see the README.md

Pull requests

Before filing a pull request run the tests:

ninja -C _build test

Use descriptive commit messages, see

https://wiki.gnome.org/Git/CommitMessages

and check

https://wiki.openstack.org/wiki/GitCommitMessages

for good examples.

Coding Style

While much of the original codebase was written using [GNU's Coding Style][1], please try to follow this document for newly written code. For existing code you should probably try to not mix different code styles too much. This coding style is heavily inspired/copied from [phosh's Coding Style][2] which itself is mostly using [libhandy's Coding Style][3].

These are the differences:

  • We're not picky about GTK+ style function argument indentation, that is having multiple arguments on one line is also o.k when there are only two arguments.
  • For callbacks we prefer the on_<action> pattern e.g. on_feedback_ended () since this helps to keep the namespace clean.
  • Since we're not a library we usually use G_DEFINE_TYPE instead of G_DEFINE_TYPE_WITH_PRIVATE (except when we need a deriveable type) since it makes the rest of the code more compact.

Source file layout

We use one file per GObject. It should be named like the GObject with the calls prefix, lowercase and '_' replaced by '-'. So a hypothetical CallsThing would go to src/calls-thing.c. The individual C files should be structured as (top to bottom of file):

  • License boilerplate

    /*
     * Copyright (C) year copyright holder
     *
     * SPDX-License-Identifier: GPL-3-or-later
     * Author: you <youremail@example.com>
     */
    
  • A log domain

    #define G_LOG_DOMAIN "CallsThing"
    

    Usually just the GObject.

  • #includes: Calls configuration (if needed) goes first, then Calls includes, then glib/gtk, then generic C headers. These blocks are separated by newline and each sorted alphabetically:

    #define G_LOG_DOMAIN "CallsThing"
    
    #include "calls-config.h"
    
    #include "calls-things.h"
    #include "calls-other-things.h"
    
    #include <gio/gdesktopappinfo.h>
    #include <glib/glib.h>
    
    #include <math.h>
    

    This helps to detect missing headers in includes.

  • docstring

  • property enum

    enum {
      PROP_0,
      PROP_FOO,
      PROP_BAR,,
      LAST_PROP
    };
    static GParamSpec *props[LAST_PROP];
    
  • signal enum

    enum {
      FOO_HAPPENED,
      BAR_TRIGGERED,
      N_SIGNALS
    };
    static guint signals[N_SIGNALS];
    
  • type definitions

    typedef struct _CallsThing {
      GObject parent;
    
      ...
    } CallsThing;
    
    G_DEFINE_TYPE (CallsThing, calls_thing, G_TYPE_OBJECT)
    
  • private methods and callbacks (these can also go at convenient places above calls_thing_constructed ()

  • calls_thing_set_properties ()

  • calls_thing_get_properties ()

  • calls_thing_constructed ()

  • calls_thing_dispose ()

  • calls_thing_finalize ()

  • calls_thing_class_init ()

  • calls_thing_init ()

  • calls_thing_new ()

  • Public methods, all starting with the object name(i.e. calls_thing_)

The reason public methods go at the bottom is that they have declarations in the header file and can thus be referenced from anywhere else in the source file.

Try to avoid forward declarations where possible. [1]: https://www.gnu.org/prep/standards/standards.html#Formatting [2]: https://gitlab.gnome.org/World/Phosh/phosh/-/blob/main/HACKING.md#coding-style [3]: https://gitlab.gnome.org/GNOME/libhandy/-/blob/main/HACKING.md#coding-style