Vhex-kernel/src/lib/libc/stdio/internal/printf_actions.c

#include <stdio.h>

// Define all actions
static void action_str(struct printf_opt *op, char n);
static void action_ptr(struct printf_opt *op, char n);
static void action_int(struct printf_opt *op, char n);
static void action_uint(struct printf_opt *op, char n);
static void action_char(struct printf_opt *op, char n);

// Define all actions which can be used
void (*action[26])(struct printf_opt *opt, char n) = {
	NULL,		NULL,		action_char,	action_int,
	NULL,		NULL,		NULL,		NULL,
	action_int,	NULL,		NULL,		NULL,
	NULL,		NULL,		action_uint,	action_ptr,
	NULL,		NULL,		action_str,	NULL,
	action_uint,	NULL,		NULL,		action_uint,
	NULL,		NULL,
};


//---
//	Disp part
//---
static void base_to_str(struct printf_opt *opt, uint64_t num, int base, int digits)
{
	char *hexa = (opt->uppercase == 1) ? "0123456789ABCDEF" : "0123456789abcdef";
	
	opt->digits = 0;
	while (num != 0 || opt->digits < digits)
	{
		opt->format[opt->digits++] = hexa[num % base];
		num = num / base;
	}
}

static void disp_format(struct printf_opt *opt)
{
	int total;

	// display pre symbols
	if (opt->sign != '\0')
		(*opt->disp_char)(opt, opt->sign);
	if (opt->base[0] != '\0')
		(*opt->disp_char)(opt, opt->base[0]);
	if (opt->base[1] != '\0')
		(*opt->disp_char)(opt, opt->base[1]);

	// padding (left)
	if ((opt->flags.minus == 1 || opt->flags.zero == 1) && opt->width > opt->digits)
	{
		total = opt->digits + (opt->sign != '\0') + (opt->base[0] != '\0') + (opt->base[1] != '\0');
		total = opt->width - (total + opt->precision);
		while (--total >= 0)
			(*opt->disp_char)(opt, (opt->flags.minus == 1) ? ' ' : '0');
	}

	// Precision
	if (opt->precision > opt->digits)
	{
		total = opt->precision - opt->digits;
		while (--total >= 0)
			(*opt->disp_char)(opt, '0');
	}

	// Display number
	int saved_digits = opt->digits;
	while (--opt->digits >= 0)
		(*opt->disp_char)(opt, opt->format[opt->digits]);

	// padding (right)
	if (opt->flags.minus == 0  && opt->flags.zero == 0 && opt->width > saved_digits)
	{
		int total = saved_digits + (opt->sign != '\0') +
			(opt->base[0] != '\0') + (opt->base[1] != '\0');
		total = opt->width - total;
		while (--total >= 0)
			(*opt->disp_char)(opt, ' ');
	}
}


//---
//	Args part
//---
static uint64_t get_arg_i(struct printf_opt *opt)
{
	switch (opt->lenght)
	{
	case 0: return ((signed char)va_arg(opt->ap, int));
	case 1: return ((short int)va_arg(opt->ap, int));
	case 2: return (va_arg(opt->ap, long int));
	case 3: return (va_arg(opt->ap, long long int));
	case 4: return (va_arg(opt->ap, intmax_t));
	case 5: return (va_arg(opt->ap, size_t));
	case 6: return (va_arg(opt->ap, ptrdiff_t));
	}
	return (va_arg(opt->ap, int));
}

static uint64_t get_arg_u(struct printf_opt *opt)
{
	switch (opt->lenght)
	{
	case 0: return ((unsigned char)va_arg(opt->ap, int));
	case 1: return ((unsigned short int)va_arg(opt->ap, int));
	case 2: return (va_arg(opt->ap, unsigned long int));
	case 3: return (va_arg(opt->ap, unsigned long long int));
	case 4: return (va_arg(opt->ap, intmax_t));
	case 5: return (va_arg(opt->ap, size_t));
	case 6: return (va_arg(opt->ap, ptrdiff_t));
	}
	return (va_arg(opt->ap, unsigned int));
}


//---
//	Actions part.
//---
static void action_str(struct printf_opt *opt, char n)
{
	const char *str;

	(void)n;
	str = va_arg(opt->ap, const char *);
	while (*str != '\0')
		(*opt->disp_char)(opt, *(str++));
}

static void action_char(struct printf_opt *opt, char n)
{
	n = (char)va_arg(opt->ap, int);
	(*opt->disp_char)(opt, n);
}

static void action_ptr(struct printf_opt *opt, char n)
{
	(void)n;
	opt->sign = '@';
	opt->base[0] = '0';
	opt->base[1] = 'x';
	base_to_str(opt, (uint32_t)va_arg(opt->ap, void*), 16, 8);
	disp_format(opt);
}

static void action_int(struct printf_opt *opt, char n)
{
	int64_t num;

	// Get data and check negative value
	// FIXME: max negative value can not be reversed
	(void)n;
	num = get_arg_i(opt);
	if (num < 0) {
		opt->sign = '-';
		num = -num;
	} else if (opt->flags.space == 1 || opt->flags.plus == 1) {
		opt->sign = (opt->flags.plus == 1) ? '+' : ' ';
	}

	// Generate / display number 
	base_to_str(opt, num, 10, 1);
	disp_format(opt);
}

static void action_uint(struct printf_opt *opt, char n)
{
	uint64_t num;
	int base;

	// Get appropriate base
	switch (n)
	{
	case 'o': base = 8; break;
	case 'x': base = 16; break;
	default:  base = 10; break;
	}

	// Display extra symbols if needed
	if (opt->flags.diez == 1)
	{
		if (n == 'o') {
			opt->base[0] = '0';
		} else if (n == 'x') {
			opt->base[0] =  '0';
			opt->base[1] = (opt->uppercase == 1) ? 'X' : 'x';
		}
	}

	// Get number
	num = get_arg_u(opt);

	// Generate / display number
	base_to_str(opt, num, base, 1);
	disp_format(opt);
}