make_feg.c

#include "ft_printf.h"

static char					*make_f(long double num, t_options *opt)
{
	uint64_t	tail;
	int			tmp;
	char		*s;
	char		*t1;
	char		*t2;

	tail = rounder(&num, num, opt->prec);
	t1 = add_apo(ft_itoa_base_u((uint64_t)num, 10, 0), opt);
	t2 = ft_strnew(opt->prec);
	tmp = opt->prec;
	while (--tmp >= 0)
	{
		t2[tmp] = tail % 10 + '0';
		tail /= 10;
	}
	t2 = prune(t2, opt);
	s = ft_strjoin(t1, t2);
	free(t1);
	free(t2);
	return (s);
}

static char					*make_e(long double num, t_options *opt)
{
	char	*s;
	char	*t1;
	char	t2[5];
	int		mov;

	mov = dotmover(num);
	num = (mov >= 0) ? num * ft_pow_pos(10, mov) : num / ft_pow_pos(10, -mov);
	t1 = make_f(num, opt);
	t1[opt->prec + 1] = '\0';
	t2[0] = 'e';
	t2[1] = (mov > 0) ? '-' : '+';
	mov = mov < 0 ? -mov : mov;
	t2[2] = mov / 10 + '0';
	t2[3] = mov % 10 + '0';
	t2[4] = '\0';
	s = ft_strjoin(t1, t2);
	free(t1);
	return (s);
}

static char					*make_g(long double num, t_options *opt)
{
	int		mov;
	char	*s;

	mov = dotmover(num);
	if (-mov < opt->prec && -mov >= -4)
	{
		opt->prec = (opt->prec == 0) ? 0 : opt->prec + mov - 1;
		opt->spec = 'f';
		s = make_f(num, opt);
	}
	else
	{
		opt->prec = (opt->prec == 0) ? 0 : opt->prec - 1;
		opt->spec = 'e';
		s = make_e(num, opt);
	}
	return (s);
}

char						*make_feg(va_list ap, t_options *opt)
{
	long double	num;
	char		*s;

	num = (opt->len == 5) ? va_arg(ap, long double) : va_arg(ap, double);
	if (num < 0)
	{
		opt->sign = '-';
		num *= -1;
	}
	opt->prec = (opt->prec < 0) ? 6 : opt->prec;
	if (opt->spec == 'f')
		s = make_f(num, opt);
	else if (opt->spec == 'e')
		s = make_e(num, opt);
	else
		s = make_g(num, opt);
	return (s);
}