ft_strnstr.c

/* ************************************************************************** */
/*                                                                            */
/*                                                        :::      ::::::::   */
/*   ft_strnstr.c                                       :+:      :+:    :+:   */
/*                                                    +:+ +:+         +:+     */
/*   By: kmoutaou <marvin@42.fr>                    +#+  +:+       +#+        */
/*                                                +#+#+#+#+#+   +#+           */
/*   Created: 2021/11/07 18:15:30 by kmoutaou          #+#    #+#             */
/*   Updated: 2021/11/19 15:16:49 by kmoutaou         ###   ########.fr       */
/*                                                                            */
/* ************************************************************************** */

/*
	ft_strnstr is a re-coded -strstr- function from <bsd/string.h> that locates
	a substring in a string.
*/

#include "libft.h"

char	*ft_strnstr(const char *str0, const char *str1, size_t n)
{
	const char		*str0_temp;
	const char		*str1_temp;
	unsigned int	i;
	unsigned int	j;

	str0_temp = (char *)str0;
	str1_temp = (char *)str1;
	i = 0;
	if (*str1 == '\0')
		return ((char *)str0_temp);
	while (str0_temp[i] && i < n)
	{
		j = 0;
		while (str1_temp[j] && str0_temp[i + j] == str1_temp[j] && i + j < n)
		{
			if (str1_temp[j + 1] == '\0')
				return ((char *)&str0_temp[i]);
			j++;
		}
		i++;
	}
	if (j == ft_strlen(str1))
		return ((char *)str0);
	return (NULL);
}