stdio.c

#include <kernel/console.h>
#include <stdio.h>
#include <string.h>

/*!
Handle the different cases of %-- in printf

@param	format the formatted string to be printed
@param	i	pointer to the index we are at
@param	args	pointer to the arguments printf received
@param	ul	whether the format prints an unsigned/long character
*/
void fmtprintf (const char* format, size_t* i, va_list* args, bool ul) {
	switch (format[*i]) {
	case 's': {
		const char* str = va_arg (*args, const char*);
		putstr (str, strlen (str));
	} break;
	case 'd':
	case 'i': {
		if (ul) {
			char buf[65] = {0};
			ulitos (va_arg (*args, uint64_t), buf, 10);
			putstr (buf, strlen (buf));
		} else {
			char buf[33] = {0};
			itos (va_arg (*args, int32_t), buf, 10);
			putstr (buf, strlen (buf));
		}
	} break;
	case 'x': {
		if (ul) {
			char buf[65] = {0};
			ulitos (va_arg (*args, uint64_t), buf, 16);
			putstr (buf, strlen (buf));
		} else {
			char buf[33] = {0};
			itos (va_arg (*args, int32_t), buf, 16);
			putstr (buf, strlen (buf));
		}
	} break;
	case 'u':
	case 'l': {
		(*i)++;
		fmtprintf (format, i, args, true);
	} break;
	default: {
		putchar ('%');
		putchar (format[*i]);
	}
	}
}

/*!
Print a formatted string to the screen.

@param	format formatted string to print
*/
void printf (const char* format, ...) {
	va_list args;
	va_start (args, format);

	bool buf = get_update_on_putch ();
	set_update_on_putch (false);
	for (size_t i = 0; i < strlen (format); i++) {
		switch (format[i]) {
		case '%': {
			i++;
			fmtprintf (format, &i, &args, false);
		} break;
		case '\t':
			size_t idx = get_idx ();
			idx = (idx / TAB_WIDTH + 1) * TAB_WIDTH;
			set_idx (idx);
			break;
		default:
			putchar (format[i]);
		}
	}
	update ();
	set_update_on_putch (buf);
}