coding_style.md

Coding style guidelines

This page provides a brief summary of the coding style used in the OpenRTX repository and is meant to provide a reference to the contributors.

General guidelines

• Code width must not exceed the limit of 80 columns.
• Variables' must be explicative of their role and written in camel case (i.e. aVarInCamelCase) when necessary.
• Integer variables must be declared using the following data types, clearly specifying their width: uint64_t, uint32_t, uint16_t, uint8_t, int64_t, int32_t, int16_t, int8_t. Use of char and unsigned char for signed and unsigned 8 bit variables is not allowed. These datatypes are defined in stdint.h and cstdint C and C++ headers, respectively.
• When multiple conditions connected by logical operators are inside if and while body, each condition must be surrounded by round brackets

if((a == 0) && (b == 1))
{
    [...]

• A space must be put between angle brackets and template argument in C++ code

std::vector< int > aVector;

• When a line of code contains more than one mathematical operation between one or more variables, the order of operations must be clearly indicated by using round brackets.

int something = (a * b) + c;

Code spacing and inlining

• Only spaces are allowed for code indentation and the indentation with amounts to four spaces.
• When multiple variables are defined and/or initialised at subsequent lines, their names and the assignment operators must be aligned.

int  aVar      = 0;
char secondVar = 'c';

• Spaces must be put between variables and mathematical, bitwise, logical and assignment operators.

int c = a + b;
if((a == 0) || (c != 0))

• Is preferable to break condition statements inside if and while body exceeding the 80 columns limit over multiple lines, dedicating each line to one condition

if((foo == 0) &&
   (goo != 0) &&
   (zoo == 3))

Brackets

• The Allmann code style must be used. The space between the end of the function name or operator and the open round bracket is optional.

void foo (int d)
{
    if ((d + 3) != 0)
    {
        bar();
    }
}

or, alternatively

void foo(int d)
{
    if((d + 3) != 0)
    {
        bar();
    }
}

Comments and documentation

• All the function prototypes defined in header files must be documented using the following Doxygen syntax

/**
 * Description...
 *
 * \param ptr: ...
 * \return ...
 */
 int func(void *ptr);