mirror of
				https://gitlab.freedesktop.org/wlroots/wlroots.git
				synced 2025-11-03 09:01:40 -05:00 
			
		
		
		
	Merge pull request #116 from ascent12/contributing
Updated CONTRIBUTING.md
This commit is contained in:
		
						commit
						0c48ef5ad8
					
				
					 2 changed files with 146 additions and 152 deletions
				
			
		
							
								
								
									
										312
									
								
								CONTRIBUTING.md
									
										
									
									
									
								
							
							
						
						
									
										312
									
								
								CONTRIBUTING.md
									
										
									
									
									
								
							| 
						 | 
				
			
			@ -1,9 +1,9 @@
 | 
			
		|||
# Contributing to wlroots
 | 
			
		||||
 | 
			
		||||
Contributing just involves sending a pull request. You will probably be more
 | 
			
		||||
successful with your contribution if you visit the [IRC
 | 
			
		||||
channel](http://webchat.freenode.net/?channels=sway-devel&uio=d4) upfront and discuss
 | 
			
		||||
your plans.
 | 
			
		||||
successful with your contribution if you visit
 | 
			
		||||
[#sway-devel](https://webchat.freenode.net/?channels=sway-devel) on
 | 
			
		||||
irc.freenode.net upfront and discuss your plans.
 | 
			
		||||
 | 
			
		||||
## Pull Requests
 | 
			
		||||
 | 
			
		||||
| 
						 | 
				
			
			@ -11,35 +11,36 @@ If you already have your own pull request habits, feel free to use them. If you
 | 
			
		|||
don't, however, allow me to make a suggestion: feature branches pulled from
 | 
			
		||||
upstream. Try this:
 | 
			
		||||
 | 
			
		||||
1. Fork sway
 | 
			
		||||
2. Clone your fork
 | 
			
		||||
3. git remote add upstream https://github.com/SirCmpwn/wlroots
 | 
			
		||||
1. Fork wlroots
 | 
			
		||||
2. `git clone https://github.com/username/wlroots && cd wlroots`
 | 
			
		||||
3. `git remote add upstream https://github.com/SirCmpwn/wlroots`
 | 
			
		||||
 | 
			
		||||
You only need to do this once. You're never going to use your fork's master
 | 
			
		||||
branch. Instead, when you start working on a feature, do this:
 | 
			
		||||
 | 
			
		||||
1. git fetch upstream
 | 
			
		||||
2. git checkout -b add-so-and-so-feature upstream/master
 | 
			
		||||
3. work
 | 
			
		||||
4. git push -u origin add-so-and-so-feature
 | 
			
		||||
5. Make pull request from your feature branch
 | 
			
		||||
1. `git fetch upstream`
 | 
			
		||||
2. `git checkout -b add-so-and-so-feature upstream/master`
 | 
			
		||||
3. Add and commit your changes
 | 
			
		||||
4. `git push -u origin add-so-and-so-feature`
 | 
			
		||||
5. Make a pull request from your feature branch
 | 
			
		||||
 | 
			
		||||
## Commit Messages
 | 
			
		||||
 | 
			
		||||
Please strive to write good commit messages. Here's some guidelines to follow:
 | 
			
		||||
 | 
			
		||||
The first line should be limited to 50 characters and should be a sentence that
 | 
			
		||||
completes the thought [When applied, this commit will...] "Implement cmd_move"
 | 
			
		||||
or "Fix #742" or "Improve performance of arrange_windows on ARM" or similar.
 | 
			
		||||
completes the thought [When applied, this commit will...] *"Implement
 | 
			
		||||
cmd_move"* or *"Fix #742"* or *"Improve performance of arrange_windows on ARM"*
 | 
			
		||||
or similar.
 | 
			
		||||
 | 
			
		||||
The subsequent lines should be seperated from the subject line by a single
 | 
			
		||||
The subsequent lines should be separated from the subject line by a single
 | 
			
		||||
blank line, and include optional details. In this you can give justification
 | 
			
		||||
for the change, [reference Github
 | 
			
		||||
issues](https://help.github.com/articles/closing-issues-via-commit-messages/),
 | 
			
		||||
or explain some of the subtler details of your patch. This is important because
 | 
			
		||||
when someone finds a line of code they don't understand later, they can use the
 | 
			
		||||
`git blame` command to find out what the author was thinking when they wrote
 | 
			
		||||
it. It's also easier to review your pull requests if they're seperated into
 | 
			
		||||
it. It's also easier to review your pull requests if they're separated into
 | 
			
		||||
logical commits that have good commit messages and justify themselves in the
 | 
			
		||||
extended commit description.
 | 
			
		||||
 | 
			
		||||
| 
						 | 
				
			
			@ -47,158 +48,153 @@ As a good rule of thumb, anything you might put into the pull request
 | 
			
		|||
description on Github is probably fair game for going into the extended commit
 | 
			
		||||
message as well.
 | 
			
		||||
 | 
			
		||||
See [here](https://chris.beams.io/posts/git-commit/) for more details.
 | 
			
		||||
 | 
			
		||||
## Coding Style
 | 
			
		||||
 | 
			
		||||
wlroots is written in C with the same style as Sway. The style guidelines is
 | 
			
		||||
[kernel
 | 
			
		||||
wlroots is written in C with a style similar to the [kernel
 | 
			
		||||
style](https://www.kernel.org/doc/Documentation/process/coding-style.rst), but
 | 
			
		||||
all braces go on the same line (*"but K&R says so!" is a silly way of justifying
 | 
			
		||||
something*). Some points to note:
 | 
			
		||||
with a few notable differences.
 | 
			
		||||
 | 
			
		||||
* Do not use typedefs unless you have a good reason
 | 
			
		||||
* Do not use macros unless you have a *really* good reason
 | 
			
		||||
* Align `case` with `switch`
 | 
			
		||||
* Tabs, not spaces
 | 
			
		||||
* `char *pointer` - note position of `*`
 | 
			
		||||
* Use logging with reckless abandon
 | 
			
		||||
* Always include braces for if/for/while/etc, even for one-liners
 | 
			
		||||
Try to keep your code conforming to C11 and POSIX as much as possible, and do
 | 
			
		||||
not use GNU extensions.
 | 
			
		||||
 | 
			
		||||
An example of well formatted code:
 | 
			
		||||
### Brackets
 | 
			
		||||
 | 
			
		||||
```C
 | 
			
		||||
#include <stdio.h>
 | 
			
		||||
#include <stdlib.h>
 | 
			
		||||
#include "log.h"
 | 
			
		||||
#include "example.h"
 | 
			
		||||
 | 
			
		||||
struct foobar {
 | 
			
		||||
	char *foo;
 | 
			
		||||
	int bar;
 | 
			
		||||
	long baz;
 | 
			
		||||
}; // Do not typedef without a good reason
 | 
			
		||||
 | 
			
		||||
int main(int argc, const char **argv) {
 | 
			
		||||
	if (argc != 4) {
 | 
			
		||||
		sway_abort("Do not run this program manually. See man 5 sway and look for output options.");
 | 
			
		||||
Brackets always go on the same line, including in functions.  
 | 
			
		||||
Always include brackets for if/while/for, even if it's a single statement.
 | 
			
		||||
```c
 | 
			
		||||
void function() {
 | 
			
		||||
	if (condition1) {
 | 
			
		||||
		do_thing1();
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	if (!registry->desktop_shell) {
 | 
			
		||||
		sway_abort("swaybg requires the compositor to support the desktop-shell extension.");
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	int desired_output = atoi(argv[1]);
 | 
			
		||||
	sway_log(L_INFO, "Using output %d of %d", desired_output, registry->outputs->length);
 | 
			
		||||
	int i;
 | 
			
		||||
	struct output_state *output = registry->outputs->items[desired_output];
 | 
			
		||||
	struct window *window = window_setup(registry, 100, 100, false);
 | 
			
		||||
	if (!window) {
 | 
			
		||||
		sway_abort("Failed to create surfaces.");
 | 
			
		||||
	}
 | 
			
		||||
	window->width = output->width;
 | 
			
		||||
	window->height = output->height;
 | 
			
		||||
	desktop_shell_set_background(registry->desktop_shell, output->output, window->surface);
 | 
			
		||||
	list_add(surfaces, window);
 | 
			
		||||
 | 
			
		||||
	cairo_surface_t *image = cairo_image_surface_create_from_png(argv[2]);
 | 
			
		||||
	double width = cairo_image_surface_get_width(image);
 | 
			
		||||
	double height = cairo_image_surface_get_height(image);
 | 
			
		||||
 | 
			
		||||
	const char *scaling_mode_str = argv[3];
 | 
			
		||||
	enum scaling_mode scaling_mode;
 | 
			
		||||
	if (strcmp(scaling_mode_str, "stretch") == 0) {
 | 
			
		||||
		scaling_mode = SCALING_MODE_STRETCH;
 | 
			
		||||
	} else if (strcmp(scaling_mode_str, "fill") == 0) {
 | 
			
		||||
		scaling_mode = SCALING_MODE_FILL;
 | 
			
		||||
	} else if (strcmp(scaling_mode_str, "fit") == 0) {
 | 
			
		||||
		scaling_mode = SCALING_MODE_FIT;
 | 
			
		||||
	} else if (strcmp(scaling_mode_str, "center") == 0) {
 | 
			
		||||
		scaling_mode = SCALING_MODE_CENTER;
 | 
			
		||||
	} else if (strcmp(scaling_mode_str, "tile") == 0) {
 | 
			
		||||
		scaling_mode = SCALING_MODE_TILE;
 | 
			
		||||
	if (condition2) {
 | 
			
		||||
		do_thing2();
 | 
			
		||||
	} else {
 | 
			
		||||
		sway_abort("Unsupported scaling mode: %s", scaling_mode_str);
 | 
			
		||||
		do_thing3();
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	for (i = 0; i < surfaces->length; ++i) {
 | 
			
		||||
		struct window *window = surfaces->items[i];
 | 
			
		||||
		if (window_prerender(window) && window->cairo) {
 | 
			
		||||
			switch (scaling_mode) {
 | 
			
		||||
			case SCALING_MODE_STRETCH:
 | 
			
		||||
				cairo_scale(window->cairo,
 | 
			
		||||
						(double) window->width / width,
 | 
			
		||||
						(double) window->height / height);
 | 
			
		||||
				cairo_set_source_surface(window->cairo, image, 0, 0);
 | 
			
		||||
				break;
 | 
			
		||||
			case SCALING_MODE_FILL:
 | 
			
		||||
			{
 | 
			
		||||
				double window_ratio = (double) window->width / window->height;
 | 
			
		||||
				double bg_ratio = width / height;
 | 
			
		||||
 | 
			
		||||
				if (window_ratio > bg_ratio) {
 | 
			
		||||
					double scale = (double) window->width / width;
 | 
			
		||||
					cairo_scale(window->cairo, scale, scale);
 | 
			
		||||
					cairo_set_source_surface(window->cairo, image,
 | 
			
		||||
							0,
 | 
			
		||||
							(double) window->height/2 / scale - height/2);
 | 
			
		||||
				} else {
 | 
			
		||||
					double scale = (double) window->height / height;
 | 
			
		||||
					cairo_scale(window->cairo, scale, scale);
 | 
			
		||||
					cairo_set_source_surface(window->cairo, image,
 | 
			
		||||
							(double) window->width/2 / scale - width/2,
 | 
			
		||||
							0);
 | 
			
		||||
				}
 | 
			
		||||
				break;
 | 
			
		||||
			}
 | 
			
		||||
			case SCALING_MODE_FIT:
 | 
			
		||||
			{
 | 
			
		||||
				double window_ratio = (double) window->width / window->height;
 | 
			
		||||
				double bg_ratio = width / height;
 | 
			
		||||
 | 
			
		||||
				if (window_ratio > bg_ratio) {
 | 
			
		||||
					double scale = (double) window->height / height;
 | 
			
		||||
					cairo_scale(window->cairo, scale, scale);
 | 
			
		||||
					cairo_set_source_surface(window->cairo, image,
 | 
			
		||||
							(double) window->width/2 / scale - width/2,
 | 
			
		||||
							0);
 | 
			
		||||
				} else {
 | 
			
		||||
					double scale = (double) window->width / width;
 | 
			
		||||
					cairo_scale(window->cairo, scale, scale);
 | 
			
		||||
					cairo_set_source_surface(window->cairo, image,
 | 
			
		||||
							0,
 | 
			
		||||
							(double) window->height/2 / scale - height/2);
 | 
			
		||||
				}
 | 
			
		||||
				break;
 | 
			
		||||
			}
 | 
			
		||||
			case SCALING_MODE_CENTER:
 | 
			
		||||
				cairo_set_source_surface(window->cairo, image,
 | 
			
		||||
						(double) window->width/2 - width/2,
 | 
			
		||||
						(double) window->height/2 - height/2);
 | 
			
		||||
				break;
 | 
			
		||||
			case SCALING_MODE_TILE:
 | 
			
		||||
			{
 | 
			
		||||
				cairo_pattern_t *pattern = cairo_pattern_create_for_surface(image);
 | 
			
		||||
				cairo_pattern_set_extend(pattern, CAIRO_EXTEND_REPEAT);
 | 
			
		||||
				cairo_set_source(window->cairo, pattern);
 | 
			
		||||
				break;
 | 
			
		||||
			}
 | 
			
		||||
			default:
 | 
			
		||||
				sway_abort("Scaling mode '%s' not implemented yet!", scaling_mode_str);
 | 
			
		||||
			}
 | 
			
		||||
 | 
			
		||||
			cairo_paint(window->cairo);
 | 
			
		||||
 | 
			
		||||
			window_render(window);
 | 
			
		||||
		}
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	while (wl_display_dispatch(registry->display) != -1);
 | 
			
		||||
 | 
			
		||||
	for (i = 0; i < surfaces->length; ++i) {
 | 
			
		||||
		struct window *window = surfaces->items[i];
 | 
			
		||||
		window_teardown(window);
 | 
			
		||||
	}
 | 
			
		||||
	list_free(surfaces);
 | 
			
		||||
	registry_teardown(registry);
 | 
			
		||||
	return 0;
 | 
			
		||||
}
 | 
			
		||||
```
 | 
			
		||||
 | 
			
		||||
### Indentation
 | 
			
		||||
 | 
			
		||||
Indentations are a single tab.
 | 
			
		||||
 | 
			
		||||
For long lines that need to be broken, the continuation line should be indented
 | 
			
		||||
with an additional tab.  
 | 
			
		||||
If the line being broken is opening a new block (functions, if, while, etc.),
 | 
			
		||||
the continuation line should be indented with two tabs, so they can't be
 | 
			
		||||
misread as being part of the block.
 | 
			
		||||
```c
 | 
			
		||||
really_long_function(argument1, argument2, ...,
 | 
			
		||||
	argument3, argument4);
 | 
			
		||||
 | 
			
		||||
if (condition1 && condition2 && ...
 | 
			
		||||
		condition3 && condition4) {
 | 
			
		||||
	do_thing();
 | 
			
		||||
}
 | 
			
		||||
```
 | 
			
		||||
 | 
			
		||||
Try to break the line in the place which you think is the most appropriate.
 | 
			
		||||
 | 
			
		||||
 | 
			
		||||
### Line Length
 | 
			
		||||
 | 
			
		||||
Try to keep your lines under 80 columns, but you can go up to 100 if it
 | 
			
		||||
improves readability.
 | 
			
		||||
 | 
			
		||||
### Names
 | 
			
		||||
 | 
			
		||||
Function and type names should be prefixed with `wlr_submodule_` (e.g. `struct
 | 
			
		||||
wlr_drm_plane`, `wlr_output_set_cursor`).  For static functions and types local
 | 
			
		||||
to a file, the names chosen aren't as important.
 | 
			
		||||
 | 
			
		||||
For include guards, use the header's filename relative to include.  Uppercase
 | 
			
		||||
all of the characters, and replace any invalid characters with an underscore.
 | 
			
		||||
 | 
			
		||||
### Construction/Destruction Functions
 | 
			
		||||
 | 
			
		||||
For functions that are responsible for constructing and destructing an object,
 | 
			
		||||
they should be written as a pair of one of two forms:
 | 
			
		||||
* `init`/`finish`: These initialize/deinitialize a type, but are **NOT**
 | 
			
		||||
responsible for allocating it. They should accept a pointer to some
 | 
			
		||||
pre-allocated memory (e.g. a member of a struct).
 | 
			
		||||
* `create`/`destroy`: These also initialize/deinitialize, but will return a
 | 
			
		||||
pointer to a `malloc`ed chunk of memory, and will `free` it in `destroy`.
 | 
			
		||||
 | 
			
		||||
A destruction function should always be able to accept a NULL pointer or a
 | 
			
		||||
zeroed value and exit cleanly; this simplifies error handling a lot.
 | 
			
		||||
 | 
			
		||||
### Error Codes
 | 
			
		||||
 | 
			
		||||
For functions not returning a value, they should return a (stdbool.h) bool to
 | 
			
		||||
indicated if they succeeded or not.
 | 
			
		||||
 | 
			
		||||
### Macros
 | 
			
		||||
 | 
			
		||||
Try to keep the use of macros to a minimum, especially if a function can do the
 | 
			
		||||
job.  If you do need to use them, try to keep them close to where they're being
 | 
			
		||||
used and `#undef` them after.
 | 
			
		||||
 | 
			
		||||
## Example
 | 
			
		||||
 | 
			
		||||
```c
 | 
			
		||||
struct wlr_backend *wlr_backend_autocreate(struct wl_display *display) {
 | 
			
		||||
	struct wlr_backend *backend;
 | 
			
		||||
	if (getenv("WAYLAND_DISPLAY") || getenv("_WAYLAND_DISPLAY")) {
 | 
			
		||||
		backend = attempt_wl_backend(display);
 | 
			
		||||
		if (backend) {
 | 
			
		||||
			return backend;
 | 
			
		||||
		}
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	const char *x11_display = getenv("DISPLAY");
 | 
			
		||||
	if (x11_display) {
 | 
			
		||||
		return wlr_x11_backend_create(display, x11_display);
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	// Attempt DRM+libinput
 | 
			
		||||
 | 
			
		||||
	struct wlr_session *session = wlr_session_create(display);
 | 
			
		||||
	if (!session) {
 | 
			
		||||
		wlr_log(L_ERROR, "Failed to start a DRM session");
 | 
			
		||||
		return NULL;
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	int gpu = wlr_session_find_gpu(session);
 | 
			
		||||
	if (gpu == -1) {
 | 
			
		||||
		wlr_log(L_ERROR, "Failed to open DRM device");
 | 
			
		||||
		goto error_session;
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	backend = wlr_multi_backend_create(session);
 | 
			
		||||
	if (!backend) {
 | 
			
		||||
		goto error_gpu;
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	struct wlr_backend *libinput = wlr_libinput_backend_create(display, session);
 | 
			
		||||
	if (!libinput) {
 | 
			
		||||
		goto error_multi;
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	struct wlr_backend *drm = wlr_drm_backend_create(display, session, gpu);
 | 
			
		||||
	if (!drm) {
 | 
			
		||||
		goto error_libinput;
 | 
			
		||||
	}
 | 
			
		||||
 | 
			
		||||
	wlr_multi_backend_add(backend, libinput);
 | 
			
		||||
	wlr_multi_backend_add(backend, drm);
 | 
			
		||||
	return backend;
 | 
			
		||||
 | 
			
		||||
error_libinput:
 | 
			
		||||
	wlr_backend_destroy(libinput);
 | 
			
		||||
error_multi:
 | 
			
		||||
	wlr_backend_destroy(backend);
 | 
			
		||||
error_gpu:
 | 
			
		||||
	wlr_session_close_file(session, gpu);
 | 
			
		||||
error_session:
 | 
			
		||||
	wlr_session_destroy(session);
 | 
			
		||||
	return NULL;
 | 
			
		||||
}
 | 
			
		||||
```
 | 
			
		||||
| 
						 | 
				
			
			
 | 
			
		|||
| 
						 | 
				
			
			@ -7,9 +7,7 @@ This is a WIP: [status](https://github.com/SirCmpwn/wlroots/issues/9)
 | 
			
		|||
 | 
			
		||||
## Contributing
 | 
			
		||||
 | 
			
		||||
Development is organized in our [IRC
 | 
			
		||||
channel](http://webchat.freenode.net/?channels=sway-devel&uio=d4), #sway-devel on
 | 
			
		||||
irc.freenode.net. Join us and ask how you can help!
 | 
			
		||||
See [CONTRIBUTING.md](https://github.com/SirCmpwn/wlroots/blob/master/CONTRIBUTING.md)
 | 
			
		||||
 | 
			
		||||
## Building
 | 
			
		||||
 | 
			
		||||
| 
						 | 
				
			
			
 | 
			
		|||
		Loading…
	
	Add table
		Add a link
		
	
		Reference in a new issue