Luna/libluna/include/luna/Format.h

#pragma once
#include <luna/Attributes.h>
#include <luna/Result.h>
#include <stdarg.h>

typedef Result<void> (*callback_t)(char, void*);
typedef void (*pure_callback_t)(char, void*);

// Used to format anything that can fail (writing to C FILEs, etc...)
Result<usize> cstyle_format(const char* format, callback_t callback, void* arg, va_list ap);

// Used to format anything that cannot fail (formatting to a string, writing to the serial port (kernel-only))
usize pure_cstyle_format(const char* format, pure_callback_t callback, void* arg, va_list ap);

// Convenience function which outputs into a fixed-size buffer (not unlike vsnprintf)
usize vstring_format(char* buf, usize max, const char* format, va_list ap);

// Convenience function which outputs into a fixed-size buffer (not unlike snprintf)
usize string_format(char* buf, usize max, const char* format, ...) _format(3, 4);