kprintf.c File Reference

Implementation of formatted print functions for kernel debugging. More...

#include "utils/kprintf.h"
#include <stdarg.h>
#include <stddef.h>

Include dependency graph for kprintf.c:

Functions
static void	itoa (unsigned long num, int base, char *buf)
	Convert an unsigned integer to a string using the given base.
int	vprintf (const char *format, va_list args)
	Variadic print function.
void	set_kprintf_console (serial_t con)
	Configures the global serial console used by kprintf.
int	kprintf (const char *format,...)
	Standard formatted print to the serial console.

Variables
static serial_t	serial_console
	Global serial console.

Detailed Description

Implementation of formatted print functions for kernel debugging.

Implements variadic print helpers and serial output wiring for the in-kernel diagnostic console.

Author

Abhin Parekadan Jose

Date

2026-05-16

Function Documentation

itoa()

static void itoa ( unsigned long  num, int  base, char *  buf  )

static

Convert an unsigned integer to a string using the given base.

This helper writes the string representation of num into buf. The resulting string is always null-terminated.

Parameters

num	Number to convert.
base	Numerical base for conversion (e.g. 10 for decimal, 16 for hex).
buf	Buffer to receive the converted string. Must be large enough to hold the result.

kprintf()

int kprintf	(	const char *	format,
			...
	)

Standard formatted print to the serial console.

A wrapper around vprintf that handles variadic argument initialization and cleanup.

Parameters

format	Formatting string containing plain text and specifiers.
...	Variable arguments matching the specifiers in the format string.

Returns

The total number of characters successfully printed.

set_kprintf_console()

void set_kprintf_console

(

serial_t

console

)

Configures the global serial console used by kprintf.

Sets the function pointers that kprintf will use to output characters.

Parameters

console

A serial_t structure containing initialized function pointers.

vprintf()

int vprintf	(	const char *	format,
		va_list	args
	)

Variadic print function.

Processes the format string and arguments, outputting characters via the configured serial console.

Supports: %c, %s, %d, %u, %x, %p. A leading 'l' length modifier (e.g. lx) is accepted, but the character after 'l' is consumed and ignored — any l followed by any character is always printed as unsigned hex, regardless of what that character actually is.

Parameters

format	Formatting string containing plain text and specifiers.
args	An initialized va_list containing the arguments to be formatted.

Returns

The total number of characters successfully printed.