Norminette Checker Skill

Purpose

Automatically check and fix C code according to 42 School's Norminette standards.

When to Use

• •Before committing code
• •When user mentions "norm", "norminette", or "42 style"
• •When creating or modifying .c or .h files
• •During code review

Key Rules

File Structure

• •Header: Must include standard 42 header with filename, author, dates
• •Guards: Header files must have #ifndef, #define, #endif guards
• •Line Length: Maximum 80 characters per line (including newline)
• •Function Length: Maximum 25 lines per function
• •Lines per File: Maximum 5 functions per file (excluding static helpers)

Formatting

• •Indentation: Tabs only (no spaces for indentation)
• •Braces: Opening brace on same line for control structures
  c

  if (condition)
  {
      // code
  }
  

• •Function Braces: Opening brace on new line
  c

  int function(void)
  {
      // code
  }
  

• •Spaces:
  • •After keywords: if (, while (, return
  • •Around operators: a + b, i = 0
  • •No space before semicolon: foo(); not foo() ;
• •Line Breaks:
  • •Empty line between functions
  • •No multiple empty lines

Naming

• •Functions: lowercase with underscores: ft_strlen, init_data
• •Variables: lowercase with underscores: last_meal_time, philo_count
• •Defines: UPPERCASE with underscores: #define MAX_PHILOS 200
• •Structs: lowercase with s_ prefix: struct s_philo, typedef struct s_data
• •Typedefs: lowercase with t_ prefix: typedef struct s_philo t_philo

Declarations

• •Variables: Declare at beginning of function/block
• •One per Line: Each variable on separate line
  c

  int     i;
  int     count;
  char    *str;
  

• •Alignment: Align variable names when declaring multiple variables
• •Initialization: Allowed: int i = 0; on declaration line

Functions

• •Max Parameters: 4 parameters maximum
• •Max Lines: 25 lines per function
• •Prototype: All non-static functions must have prototype in header
• •Return: Must return value or void
• •Empty Line: Between function definition and first statement

Forbidden

• •for loops (must use while)
• •Multiple assignments in one line: a = b = 0;
• •Nested ternary operators
• •switch, case, goto
• •Variable-length arrays (VLA)
• •Implicit type conversions
• •Function calls in conditions without proper checks

Common Issues and Fixes

Issue: Line too long

// BAD (>80 chars)
printf("Philosopher %d has taken a fork and is eating delicious spaghetti\n", id);

// GOOD
printf("Philosopher %d has taken a fork\n", id);

Issue: Incorrect brace placement

// BAD
if (condition) {
    code();
}

// GOOD
if (condition)
{
    code();
}

Issue: Multiple declarations

// BAD
int i, j, k;

// GOOD
int     i;
int     j;
int     k;

Issue: Forbidden for loop

// BAD
for (int i = 0; i < n; i++)
    do_something(i);

// GOOD
int     i;

i = 0;
while (i < n)
{
    do_something(i);
    i++;
}

Checking Process

1. •Run norminette: norminette -R CheckForbiddenSourceHeader
2. •Check each error and warning
3. •Fix systematically from top to bottom
4. •Re-run until no errors

Auto-Fix Patterns

When fixing code:

• •Preserve logic and functionality
• •Maintain readability
• •Split long lines intelligently
• •Break long functions into smaller helper functions
• •Add static keyword to helper functions
• •Ensure proper alignment and spacing