42_ft_printf/ft_vsprintf.c

/* ************************************************************************** */
/*                                                                            */
/*                                                        :::      ::::::::   */
/*   ft_vsprintf.c                                      :+:      :+:    :+:   */
/*                                                    +:+ +:+         +:+     */
/*   By: cchauvet <cchauvet@student.42angoulem      +#+  +:+       +#+        */
/*                                                +#+#+#+#+#+   +#+           */
/*   Created: 2022/10/06 10:44:36 by cchauvet          #+#    #+#             */
/*   Updated: 2022/10/10 19:32:04 by cchauvet         ###   ########.fr       */
/*                                                                            */
/* ************************************************************************** */

#include "printf.h"

static size_t	ft_seglen(const char *str)
{
	size_t	i;

	i = 0;
	while ((str[i] != 0 && str[i] != '%') || (str[i] == '%' && i == 0))
		i++;
	return (i);
}

static char	*ft_strfjoin(char *s1, char *s2)
{
	size_t	i;
	size_t	j;
	char	*out;

	out = malloc((ft_strlen(s1) + ft_seglen(s2) + 1) * sizeof(char));
	if (out == NULL)
		return (NULL);
	i = 0;
	while (s1[i] != 0)
	{
		out[i] = s1[i];
		i++;
	}
	free(s1);
	j = 0;
	while ((s2[j] != 0 && s2[j] != '%') || (s2[j] == '%' && j == 0))
	{
		out[i + j] = s2[j];
		j++;
	}
	free(s2);
	out[i + j] = 0;
	return (out);
}

static char	*ft_argtoa(int c, va_list args)
{
	char	*out;

	if (c == 'c')
		return (ft_ctoa(va_arg(args, int)));
	if (c == 's')
		return (ft_strdup(va_arg(args, char *)));
	if (c == 'd' || c == 'i')
		return (ft_itoa(va_arg(args, long int)));
	if (c == 'p')
		return (ft_ptoa(va_arg(args, void *)));
	if (c == 'x')
		return (ft_ltoabase(va_arg(args, long int), "0123456789abcdef"));
	if (c == 'X')
		return (ft_ltoabase(va_arg(args, long int), "0123456789ABCDEF"));
	if (c == 'u')
		return (ft_ultoabase(va_arg(args, unsigned long int), "0123456789"));
	if (c == '%')
		return (ft_strdup("%"));
	out = ft_strdup("% ");
	if (out == NULL)
		return (NULL);
	out[1] = c;
	return (out);
}

char	*ft_vsprintf(char *str, const char *format, va_list va)
{
	char	*cformat;
	char	*ccformat;
	char	*mid;

	cformat = ft_strdup(format);
	ccformat = cformat;
	if (str == NULL || cformat == NULL)
		return (0);
	while (cformat != NULL)
	{
		if (cformat[0] != '%')
			str = ft_strfjoin(str, ft_strdup(cformat));
		cformat = ft_strchr(cformat, '%');
		if (cformat == NULL)
			break ;
		cformat += 1;
		mid = ft_argtoa(cformat[0], va);
		while (mid == NULL)
			mid = ft_strdup("(null)");
		str = ft_strfjoin(str, mid);
		cformat += 1;
	}
	free(ccformat);
	return (str);
}