less_retarded_wiki

Programming Style

Here we discuss a good programming style (formatting, conventions etc.). Remember that nothing is set in stone, the most important thing is to be consistent and actually think about why you're doing things the way you're doing them. Think from the point of view of a programmer who gets just your source code without any way to communicate with you, make his life as easy as possible.

Recommended C Programming Style

This is our recommendation or perhaps just a suggestion/guide on the C programming style.

• Respect the LRS principles.
• Use two spaces for indentation. Do not use tabs! Tabs are ugly, tricky non-standard behaving characters.
• Format to 80 columns or a similar width. Keep in mind the source may be edited on computers with small screens (like old thinkpads) with a screen split vertically.
• Write opening and closing curly brackets on its own line, in the same columns, e.g.:

if (a == b)
{
  doSomething();
  doSomethingElse();
}

• Prefer not writing curly brackets if you don't have to (e.g. with a single command in the block). You may still do it in tricky cases like nested branches.
• naming:
  • camelCase for variables and functions (like myVariable). Global and big-scope variables should have a descriptive, self-documenting name (e.g. getTicksSinceStart), local/short-scope ones can be just one letter.
  • CapitalCamelCase for data types (like ImaginaryNumber).
  • ALL_CAPS_SNAKE_CASE for macros and constants (like PI or MY_MACRO).
  • It is advised that for your project you come up with a three letter namespace prefix that will come in front of your global identifiers. (E.g. small3dlib uses the prefix S3L_, SDL uses SDL etc.). If you choose a prefix XYZ_, prepend it to all global identifiers, it will prevent name clashes and help readability.
  • Prefix private global identifiers with _, e.g. _myInternalVar.
• Use spaces to make code more readable, so e.g. int x = 10, y = 20; instead of int x=10,y=20;, write space between if and its condition etc.
• Use blank lines to logically group relevant lines of code. E.g.:

int a = x;
char b = y;

c += 3 * a;
d -= b;

if (c < d)
a = b;

• Each file shall have a global comment with at least: short description of the file's purpose (this is almost always missing), license, the author(s) and year of creation.
• Use comments to make your code better readable and searchable (add keywords to relevant parts of code etc.).
• Don't use enums, use #defines.
• Global variables are great, use them. Long functions are fine.
• Adhere to C99 or C89 standard.
• Try to not create many source files, many times your project can very well be in a single file which is the ideal case. Create header only libraries If you have multiple files, keep them in the same directory and try to have just a single compilation unit (only one .c file with several .h files). Try to make files no longer than 10k lines.
• Use the LRS version numbering system.
• Do not use non-ASCII characters in the source code.

All content available under CC0 1.0 (public domain). Send comments and corrections to drummyfish at disroot dot org.