tiagochicoo/ft_printf

printf

Because putnbr and putstr aren’t enough

Summary: This project is pretty straight forward. You will recode printf. Hopefully you will be able to reuse it in future project without the fear of being flagged as a cheater. You will mainly learn how to use variadic arguments.

Contents

• I Introduction
• II Common Instructions
• III Mandatory part
• IV Bonus part

Chapter I

Introduction

The versatility of theprintffunction inCrepresents a great exercise in programming for us. This project is of moderate difficulty. It will enable you to discover variadic functions inC. The key to a successfulft_printfis a well-structured and good extensible code.

Chapter II

Common Instructions

• Your project must be written in accordance with the Norm. If you have bonus files/functions, they are included in the norm check and you will receive a 0 if there is a norm error inside.
• Your functions should not quit unexpectedly (segmentation fault, bus error, double free, etc) apart from undefined behaviors. If this happens, your project will be considered non functional and will receive a 0 during the evaluation.
• All heap allocated memory space must be properly freed when necessary. No leaks will be tolerated.
• If the subject requires it, you must submit a Makefilewhich will compile your source files to the required output with the flags-Wall,-Wextraand-Werror, and your Makefile must not relink.
• YourMakefilemust at least contain the rules$(NAME),all,clean,fcleanand re.
• To turn in bonuses to your project, you must include a rulebonusto your Makefile, which will add all the various headers, librairies or functions that are forbidden on the main part of the project. Bonuses must be in a different file_bonus.{c/h}. Mandatory and bonus part evaluation is done separately.
• If your project allows you to use your libft, you must copy its sources and its associatedMakefilein alibftfolder with its associated Makefile. Your project’s Makefilemust compile the library by using itsMakefile, then compile the project.
• We encourage you to create test programs for your project even though this work won’t have to be submitted and won’t be graded. It will give you a chance to easily test your work and your peers’ work. You will find those tests especially useful during your defence. Indeed, during defence, you are free to use your tests and/or the tests of the peer you are evaluating.
• Submit your work to your assigned git repository. Only the work in the git reposi- tory will be graded. If Deepthought is assigned to grade your work, it will be done after your peer-evaluations. If an error happens in any section of your work during Deepthought’s grading, the evaluation will stop.

Chapter III

Mandatory part

Program name libftprintf.a
Turn in files *.c, */*.c, *.h, */*.h, Makefile
Makefile all, clean, fclean, re, bonus
External functs. malloc, free, write, va_start, va_arg, va_copy,
va_end
Libft authorized yes
Description Write a library that contains ft_printf, a function
that will mimic the real printf

• The prototype of ft_printf should beint ft_printf(const char *, ...);
• You have to recode thelibc’sprintffunction
• It must not do the buffer management like the realprintf
• It will manage the following conversions: cspdiuxX%
• It will manage any combination of the following flags: ’-0.*’ and minimum field width with all conversions
• It will be compared with the real printf
• You must use the commandarto create your librairy, using the commandlibtool is forbidden.

man 3 printf / man 3 stdarg

Chapter IV

Bonus part

• If the Mandatory part is not perfect don’t even think about bonuses
• You don’t need to do all the bonuses
• Manage one or more of the following conversions:nfge
• Manage one or more of the following flags:l ll h hh
• Manage all the following flags: ’# +’ (yes, one of them is a space)

ft_printf's Issues

pointer being freed was not allocated

On test main, I have this issue:

this is my ft_printf: Helloa.out(50308,0x100604580) malloc: *** error for object 0x1004c3348: pointer being freed was not allocated
a.out(50308,0x100604580) malloc: *** set a breakpoint in malloc_error_break to debug
/bin/sh: line 1: 50308 Abort trap: 6 ./a.out
make: *** [cc] Error 134

`#include "./includes/ft_printf.h"

int main(void)
{
char *str;

str = (char *)malloc(sizeof(char) * 6);
if (str == NULL)
	return (0);
str = "Hello";

ft_printf("this is my ft_printf: %s\n", str);
printf("this is my string: %s\n", str);
return (0);

}`