mirror of
https://gitee.com/openharmony/third_party_mesa3d
synced 2024-11-23 07:19:50 +00:00
74a1f103b6
Reviewed-by: Dave Airlie <airlied@redhat.com> Reviewed-by: Pierre-Eric Pelloux-Prayer <pierre-eric.pelloux-prayer@amd.com> Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/14066>
133 lines
4.7 KiB
ReStructuredText
133 lines
4.7 KiB
ReStructuredText
Coding Style
|
|
============
|
|
|
|
Mesa is over 20 years old and the coding style has evolved over time.
|
|
Some old parts use a style that's a bit out of date. Different sections
|
|
of mesa can use different coding style as set in the local EditorConfig
|
|
(.editorconfig) and/or Emacs (.dir-locals.el) file. Alternatively the
|
|
following is applicable. If the guidelines below don't cover something,
|
|
try following the format of existing, neighboring code.
|
|
|
|
Basic formatting guidelines
|
|
|
|
- 3-space indentation, no tabs.
|
|
- Limit lines to 78 or fewer characters. The idea is to prevent line
|
|
wrapping in 80-column editors and terminals. There are exceptions,
|
|
such as if you're defining a large, static table of information.
|
|
- Opening braces go on the same line as the if/for/while statement. For
|
|
example:
|
|
|
|
.. code-block:: c
|
|
|
|
if (condition) {
|
|
foo;
|
|
} else {
|
|
bar;
|
|
}
|
|
|
|
- Put a space before/after operators. For example, ``a = b + c;`` and
|
|
not ``a=b+c;``
|
|
- This GNU indent command generally does the right thing for
|
|
formatting:
|
|
|
|
.. code-block:: console
|
|
|
|
indent -br -i3 -npcs --no-tabs infile.c -o outfile.c
|
|
|
|
- Use comments wherever you think it would be helpful for other
|
|
developers. Several specific cases and style examples follow. Note
|
|
that we roughly follow `Doxygen <http://www.doxygen.nl>`__
|
|
conventions.
|
|
|
|
Single-line comments:
|
|
|
|
.. code-block:: c
|
|
|
|
/* null-out pointer to prevent dangling reference below */
|
|
bufferObj = NULL;
|
|
|
|
Or,
|
|
|
|
.. code-block:: c
|
|
|
|
bufferObj = NULL; /* prevent dangling reference below */
|
|
|
|
Multi-line comment:
|
|
|
|
.. code-block:: c
|
|
|
|
/* If this is a new buffer object id, or one which was generated but
|
|
* never used before, allocate a buffer object now.
|
|
*/
|
|
|
|
We try to quote the OpenGL specification where prudent:
|
|
|
|
.. code-block:: c
|
|
|
|
/* Page 38 of the PDF of the OpenGL ES 3.0 spec says:
|
|
*
|
|
* "An INVALID_OPERATION error is generated for any of the following
|
|
* conditions:
|
|
*
|
|
* * <length> is zero."
|
|
*
|
|
* Additionally, page 94 of the PDF of the OpenGL 4.5 core spec
|
|
* (30.10.2014) also says this, so it's no longer allowed for desktop GL,
|
|
* either.
|
|
*/
|
|
|
|
Function comment example:
|
|
|
|
.. code-block:: c
|
|
|
|
/**
|
|
* Create and initialize a new buffer object. Called via the
|
|
* ctx->Driver.CreateObject() driver callback function.
|
|
* \param name integer name of the object
|
|
* \param type one of GL_FOO, GL_BAR, etc.
|
|
* \return pointer to new object or NULL if error
|
|
*/
|
|
struct gl_object *
|
|
_mesa_create_object(GLuint name, GLenum type)
|
|
{
|
|
/* function body */
|
|
}
|
|
|
|
- Put the function return type and qualifiers on one line and the
|
|
function name and parameters on the next, as seen above. This makes
|
|
it easy to use ``grep ^function_name dir/*`` to find function
|
|
definitions. Also, the opening brace goes on the next line by itself
|
|
(see above.)
|
|
- Function names follow various conventions depending on the type of
|
|
function:
|
|
|
|
+---------------------+------------------------------------------+
|
|
| Convention | Explanation |
|
|
+=====================+==========================================+
|
|
| ``glFooBar()`` | a public GL entry point (in |
|
|
| | :file:`glapi_dispatch.c`) |
|
|
+---------------------+------------------------------------------+
|
|
| ``_mesa_FooBar()`` | the internal immediate mode function |
|
|
+---------------------+------------------------------------------+
|
|
| ``save_FooBar()`` | retained mode (display list) function in |
|
|
| | :file:`dlist.c` |
|
|
+---------------------+------------------------------------------+
|
|
| ``foo_bar()`` | a static (private) function |
|
|
+---------------------+------------------------------------------+
|
|
| ``_mesa_foo_bar()`` | an internal non-static Mesa function |
|
|
+---------------------+------------------------------------------+
|
|
|
|
- Constants, macros and enum names are ``ALL_UPPERCASE``, with \_
|
|
between words.
|
|
- Mesa usually uses camel case for local variables (Ex:
|
|
``localVarname``) while Gallium typically uses underscores (Ex:
|
|
``local_var_name``).
|
|
- Global variables are almost never used because Mesa should be
|
|
thread-safe.
|
|
- Booleans. Places that are not directly visible to the GL API should
|
|
prefer the use of ``bool``, ``true``, and ``false`` over
|
|
``GLboolean``, ``GL_TRUE``, and ``GL_FALSE``. In C code, this may
|
|
mean that ``#include <stdbool.h>`` needs to be added. The
|
|
``try_emit_*`` method ``src/mesa/state_tracker/st_glsl_to_tgsi.cpp``
|
|
can serve as an example.
|