From bc53060626ca78bce8fbb6dcbb7ecfc8e53db0ef Mon Sep 17 00:00:00 2001
From: hugogogo <hugogogo@protonmail.com>
Date: Wed, 23 Mar 2022 21:52:04 +0100
Subject: [PATCH] add lstremove_next and lstadd_back now return

---
 Makefile                 |  3 ++-
 includes/libft.h         |  5 +++--
 srcs/ft_lstadd_back.c    | 12 ++++++++----
 srcs/ft_lstnew.c         | 10 ++++------
 srcs/ft_lstremove_next.c | 30 ++++++++++++++++++++++++++++++
 5 files changed, 47 insertions(+), 13 deletions(-)
 create mode 100644 srcs/ft_lstremove_next.c

diff --git a/Makefile b/Makefile
index ce72c00..c3937a8 100644
--- a/Makefile
+++ b/Makefile
@@ -120,7 +120,8 @@ SRCS	=	ft_memset.c \
 			ft_sqrt.c \
 			ft_free_tab.c \
 			\
-			ft_arrintchr.c
+			ft_arrintchr.c \
+			ft_lstremove_next.c
 
 
 ODIR	=	./builds
diff --git a/includes/libft.h b/includes/libft.h
index da6babe..56b1d85 100644
--- a/includes/libft.h
+++ b/includes/libft.h
@@ -6,7 +6,7 @@
 /*   By: hulamy <marvin@42.fr>                      +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2019/11/25 14:45:53 by hulamy            #+#    #+#             */
-/*   Updated: 2022/03/23 14:22:33 by simplonco        ###   ########.fr       */
+/*   Updated: 2022/03/23 21:51:14 by simplonco        ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
@@ -65,9 +65,9 @@ typedef struct		s_list
 
 t_list				*ft_lstnew(void *content);
 void				ft_lstadd_front(t_list **alst, t_list *n);
+void				*ft_lstadd_back(t_list **alst, t_list *n);
 int					ft_lstsize(t_list *lst);
 t_list				*ft_lstlast(t_list *lst);
-void				ft_lstadd_back(t_list **alst, t_list *n);
 void				ft_lstdelone(t_list *lst, void (*del)(void *));
 void				ft_lstclear(t_list **lst, void (*del)(void *));
 void				ft_lstiter(t_list *lst, void (*f)(void *));
@@ -114,5 +114,6 @@ int					ft_sqrt(int i);
 void				ft_free_tab(char **tab);
 
 int					ft_arrintchr(int * intarr, int comp, size_t size);
+void				ft_lstremove_next(t_list *lst, void (*del)(void *));
 
 #endif
diff --git a/srcs/ft_lstadd_back.c b/srcs/ft_lstadd_back.c
index 315119b..dceb7e0 100644
--- a/srcs/ft_lstadd_back.c
+++ b/srcs/ft_lstadd_back.c
@@ -6,13 +6,14 @@
 /*   By: hulamy <marvin@42.fr>                      +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2019/11/25 14:11:53 by hulamy            #+#    #+#             */
-/*   Updated: 2019/11/25 14:36:12 by hulamy           ###   ########.fr       */
+/*   Updated: 2022/03/23 21:50:42 by simplonco        ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
 /*
-**	add an element to the end of a list
-**	or first if list has no element so far
+**	add an element to the end of a list, or first if list has no element yet
+**  return NULL if element is NULL (eg, it returned from ft_lstnew and failed)
+**         or else address to the element added
 */
 
 /*
@@ -71,10 +72,12 @@
 
 #include "libft.h"
 
-void	ft_lstadd_back(t_list **alst, t_list *new)
+void	*ft_lstadd_back(t_list **alst, t_list *new)
 {
 	t_list	*tmp;
 
+	if (!new)
+		return (NULL);
 	if (alst)
 	{
 		tmp = *alst;
@@ -87,4 +90,5 @@ void	ft_lstadd_back(t_list **alst, t_list *new)
 			tmp->next = new;
 		}
 	}
+	return (tmp);
 }
diff --git a/srcs/ft_lstnew.c b/srcs/ft_lstnew.c
index 401f6c9..0c64f4e 100644
--- a/srcs/ft_lstnew.c
+++ b/srcs/ft_lstnew.c
@@ -6,7 +6,7 @@
 /*   By: hulamy <marvin@42.fr>                      +#+  +:+       +#+        */
 /*                                                +#+#+#+#+#+   +#+           */
 /*   Created: 2019/11/25 14:16:20 by hulamy            #+#    #+#             */
-/*   Updated: 2019/11/25 14:29:46 by hulamy           ###   ########.fr       */
+/*   Updated: 2022/03/23 20:24:40 by simplonco        ###   ########.fr       */
 /*                                                                            */
 /* ************************************************************************** */
 
@@ -48,12 +48,10 @@ t_list	*ft_lstnew(void *content)
 {
 	t_list		*lst;
 
-	if (!(lst = (t_list *)malloc(sizeof(*lst))))
+	lst = (t_list *)malloc(sizeof(*lst));
+	if (!lst)
 		return (NULL);
-	if (!content)
-		lst->content = NULL;
-	else
-		lst->content = content;
+	lst->content = content;
 	lst->next = NULL;
 	return (lst);
 }
diff --git a/srcs/ft_lstremove_next.c b/srcs/ft_lstremove_next.c
new file mode 100644
index 0000000..926f5d5
--- /dev/null
+++ b/srcs/ft_lstremove_next.c
@@ -0,0 +1,30 @@
+/* ************************************************************************** */
+/*                                                                            */
+/*                                                        :::      ::::::::   */
+/*   ft_lstremove_next.c                                :+:      :+:    :+:   */
+/*                                                    +:+ +:+         +:+     */
+/*   By: simplonco <marvin@42.fr>                   +#+  +:+       +#+        */
+/*                                                +#+#+#+#+#+   +#+           */
+/*   Created: 2022/03/23 21:42:05 by simplonco         #+#    #+#             */
+/*   Updated: 2022/03/23 21:42:55 by simplonco        ###   ########.fr       */
+/*                                                                            */
+/* ************************************************************************** */
+
+/*
+ * remove the next element of the list, delete its content, and free it
+ * then rejoin the list without this element
+ */
+
+#include "libft.h"
+
+void	ft_lstremove_next(t_list *lst, void (*del)(void *))
+{
+	t_list	*next_tmp;
+
+	if (!lst || !lst->next || !del)
+		return ;
+	next_tmp = lst->next->next;
+	del(lst->next->content);
+	free(lst->next);
+	lst->next = next_tmp;
+}