This project has been created as part of the 42 curriculum by dchernyk.

Description

Libft is a library for the C programming language. The goal is to practice Makefile, header files, and function linking in order to create a static library. It also helps in learning how linked lists work.

Instructions

To use the Makefile commands, you need to be in the project directory and run:

Command	Description
make	compiles every .c file into .o files and links them into libft.a
all	default behavior
clean	removes all .o files
fclean	removes all .o and .a files
re	removes all .o and .a files and runs make again

Resources

Tester

https://github.com/xicodomingues/francinette

It has been abandoned for a long time, but the tests still cover most topics. It is made for the old libft subject, when the bonus part was not mandatory. In order to run it, all linked files need to be added to the BONUS variable in the Makefile. Then create .o files from them.

BOFILES = $(BCFILES:.c=.o)

Create a bonus rule to build the archive.

bonus: $(NAME) $(BOFILES)
	ar rcs $(NAME) $(BOFILES)

If https://github.com/Tripouille/libftTester is installed:

so:
	$(CC) -fPIC $(CFLAGS) -shared -o libft.so $(CFILES)

AI Usage

AI was used as an assistant tool (Claude, ChatGPT, and Gemini). Created AI agents do not provide direct answers and behave according to the 42 AI approach. The main behavior is to encourage me to explain my code and provide information so that, in the end, I have a full understanding of the situation.

Functions description

Function	Description
isalpha	Checks if a character is an alphabetic letter (A–Z or a–z).
isdigit	Checks if a character is a decimal digit (0–9).
isalnum	Checks if a character is alphanumeric (A–Z, a–z, or 0–9).
isascii	Checks if a character is within the ASCII range (0–127).
isprint	Checks if a character is printable, including space.
strlen	Returns the length of a string excluding the null terminator.
memset	Fills a block of memory with a specified byte value.
bzero	Sets a block of memory to zero.
memcpy	Copies memory from source to destination (no overlap handling).
memmove	Copies memory safely, handling overlapping regions.
strlcpy	Copies a string into a buffer with size limitation and guarantees null-termination.
strlcat	Appends a string to another with size limitation and null-termination.
toupper	Converts a lowercase letter to uppercase if possible.
tolower	Converts an uppercase letter to lowercase if possible.
strchr	Finds the first occurrence of a character in a string.
strrchr	Finds the last occurrence of a character in a string.
strncmp	Compares two strings up to a given number of characters.
memchr	Searches for a byte in a memory block.
memcmp	Compares two memory blocks byte by byte.
strnstr	Searches for a substring in a string within a limited length.
atoi	Converts a string to an integer.
calloc	Allocates memory for an array and initializes it to zero.
strdup	Allocates memory and returns a duplicate of a string.
ft_substr	Allocates and returns a substring from string s, starting at index start and with a maximum length of len. Returns NULL if allocation fails.
ft_strjoin	Allocates and returns a new string which is the result of concatenating s1 and s2. Returns NULL if allocation fails.
ft_strtrim	Allocates and returns a copy of s1 with all characters in set removed from the beginning and the end of the string. Returns NULL if allocation fails.
ft_split	Allocates and returns an array of strings obtained by splitting s using the character c as a delimiter. The array is NULL-terminated. Returns NULL if allocation fails.
ft_itoa	Allocates and returns a string representing the integer n, handling negative numbers. Returns NULL if allocation fails.
ft_strmapi	Applies function f to each character of string s, using its index and character, and returns a new allocated string with the results. Returns NULL if allocation fails.
ft_striteri	Applies function f to each character of string s, passing its index and a pointer to the character, allowing in-place modification. No return value.
ft_putchar_fd	Outputs character c to file descriptor fd using write.
ft_putstr_fd	Outputs string s to file descriptor fd using write.
ft_putendl_fd	Outputs string s followed by a newline to file descriptor fd using write.
ft_putnbr_fd	Outputs integer n to file descriptor fd using write, handling negative numbers.
ft_lstnew	Allocates and returns a new list node. The content field is initialized with the given parameter and next is set to NULL.
ft_lstadd_front	Adds the node new at the beginning of the list pointed to by lst.
ft_lstsize	Returns the number of nodes in the linked list.
ft_lstlast	Returns the last node of the linked list.
ft_lstadd_back	Adds the node new at the end of the list pointed to by lst.
ft_lstdelone	Frees the memory of a single node using del to free its content, then frees the node itself (does not affect other nodes).
ft_lstclear	Deletes and frees the entire list, applying del to each node's content, and sets the list pointer to NULL.
ft_lstiter	Iterates through the list and applies function f to the content of each node.
ft_lstmap	Creates a new list by applying function f to each node's content. Uses del to free content if allocation fails, and returns the new list or NULL on failure.