This project has been created as part of the 42 curriculum

Description

This repository contains pre-selected functions from the standard C library as an attempt to create our own usable library in the future. It contains functions -namely described under- regarding character classification, string and memory manipulation, duplication and comparison, simple characters terminal printing as well as basic through advanced linked list handling.

Instructions

Every file is situated in the project's root, meaning no directory or hierarchy needs to be handled other than keeping the library together. A Makefile is included along a header file making compilation as simple as make or make all. Other necessary make rules namely $(NAME) clean fclean and re are included. This libft can be added and used in its own directory in other projects by calling its Makefile within a libft.a rule such as below :

$(NAME): $(OBJ) libft.a
    $(CC) $(CFLAGS) $(OBJ) -LLibft -lft -o $(NAME)

libft.a:
    cd libft && make

Detailed list

This library consists of 43 functions that you can find a description of below, classed by purpose and notions.

Functions name	Description and return type
	Classification functions
ft_isalpha	check if argument is an alphabetic character and returns a boolean value.
ft_isdigit	check if argument is a digit and returns a boolean value.
ft_isalnum	check if argument is an alphanumeric character and returns a boolean value.
ft_isascii	check if argument is an ASCII character (0 to 127) and returns a boolean value.
ft_isprint	check if argument is any printable character (32 to 126) and returns a boolean value.
	Variable conversion and modification
ft_itoa	return a string created from an int value literally transcribed to ASCII characters, covers all possible int values.
ft_ltoa	return a string created from a long int value literally transcribed to ASCII characters, covers all possible long int values.
ft_lltoa	return a string created from a long long int value literally transcribed to ASCII characters, covers all possible long long int values.
ft_atoi	return an int equivalent of an input string of characters by following set rules, covers all possible int values.
ft_atol	return a long int equivalent of an input string of characters by following set rules, covers all possible long int values.
ft_atoll	return a long long int equivalent of an input string of characters by following set rules, covers all possible long long int values.
ft_toupper	return argument as uppercase if possible, otherwise argument doesn't change.
ft_tolower	return argument as lowercase if possible, otherwise argument doesn't change.
	String and memory iteration and comparison
ft_memcmp	compare two memory areas on an input length until bytes differ, returning the difference of value of byte1 - byte2, otherwise 0.
ft_memchr	locate and return a pointer to the first occurence of a character in a memory area, otherwise NULL.
ft_strlen	count and return input string length.
ft_strcmp	compare two strings until characters differ, returning the difference of value of char1 - char2, otherwise 0.
ft_strncmp	compare two strings on an input length until characters differ, returning the difference of value of char1 - char2, otherwise 0.
ft_strchr	locate and return a pointer to the first occurence of a character in a string, otherwise NULL.
ft_strrchr	locate and return a pointer to the last occurence of a character in a string, otherwise NULL.
ft_strnstr	locate a substring in a string and return its pointer within the source, otherwise NULL.
ft_striteri	apply an input function on every character of a source string, no return value.
	String and memory copy and concatenation
ft_bzero	replace input amount of bytes by zeroes, no return value.
ft_memset	replace input amount of bytes by argument and returns pointer to result.
ft_memcpy	copy an input length of memory from a source to a destination, regardless of memory overlap, returns pointer to destination.
ft_memmove	copy an input length of memory from a source to a destination, making sure memory overlap doesn't duplicate or erase data, returns pointer to destination.
ft_strlcpy	copy on an input maximum length a string of characters from a source to a destination and returns the amount of concerned bytes.
ft_strlcat	concatenate a source at the end of a destination, only covering an input maximum length, returns the amount of concerned bytes.
	String and memory allocationm duplication and manipulation
ft_calloc	allocate an input length of memory and set all its bytes to 0, returning its pointer.
ft_strdup	creates a string of characters by duplicating an input source, returning an allocated pointer to the destination.
ft_substr	return a string of characters copied from a source from an index start and on a maximum input length.
ft_strtrim	create and return a string consisting of a source trimmed of a set of characters from its beginning and its end.
ft_split	split a source string into an array of smaller string based on a separator added as argument.
ft_strjoin	return a string of characters created from the concatenation of two input sources.
ft_strmapi	create and return a string of characters from the result of an input function applied to every characters of a source string.
	Content reading and printing in given file descriptor
ft_putchar_fd	output using write function a single character to a file descriptor.
ft_putstr_fd	output using write function a string of characters to a file descriptor.
ft_putendl_fd	output using write function a tring of characters to a file descriptor, followed by a new line.
ft_putnbr_fd	output using write function an int value with its possible negative sign to a file descriptor.
get_next_line	read and returns a single line from a fiLe descriptor, either ending with a \n or the last character of the file.
	Linked list creation, manipulation and deletion
ft_lstnew	create and return the pointer of a new structure usable as a chained list element.
ft_lstsize	count the number of elements in a pointed chained list, returning the result.
ft_lstlast	find and return the pointer of the last element of a pointed chained list.
ft_lstadd_front	add a chained list element to the front of a pointed source list.
ft_lstadd_back	add a chained list element to the back of a pointed source list.
ft_lstjoin	create a table of pointers regrouping all given list's content in an allocated memory area, if second argument is different from 0, also delete list.
ft_lstiter	apply an input function on every content of a pointed chained list, no return value.
ft_lstmap	return a chained list created from the result of an input function applied to every content of a source list.
ft_lstdelone	delete a single pointed to structure's content using a function added as argument and free the node itself.
ft_lstclear	delete a chained list elements' content and free their allocated memory, no return value.
	Printf lib functions
ft_printf	output in STDOUT channel formatted arguments following printf behavior as declared in stdio.h, does not support error throwing nor numeral or string justifying.
ft_put_char	output in STDOUT channel the character passed in argument.
ft_put_str	output in STDOUT channel the string of characters passed in argument.
ft_put_ptr	output in STDOUT channel the pointer passed in argument, in format "0xhexadecimal".
ft_put_signed	output in STDOUT channel the signed int passed in argument based on entered digits.
ft_put_unsigned	output in STDOUT channel the unsigned int passed in argument based on entered digits.
ft_put_lsigned	output in STDOUT channel the signed long int passed in argument based on entered digits.
ft_put_lunsigned	output in STDOUT channel the unsigned long int passed in argument based on entered digits.
ft_put_llsigned	output in STDOUT channel the signed long long int passed in argument based on entered digits.
ft_put_llunsigned	output in STDOUT channel the unsigned long long int passed in argument based on entered digits.

Ressources

No AI was used in the making of this project. Instructions on functions' behavior came from the project's subject, linux' manual and peer-learning. Programs used to test functions can be found below :

• libftTester by Tripouille
• Libftest by jtoty
• libfterator by Blaeste