ft_printf

[42 Cursus] This project involves reprogramming the printf function in C. The goal is to understand variadic functions and string formatting while creating a lightweight version of the standard printf function. Key features include handling various format specifiers and managing memory efficiently.

Keywords

• Variadic Functions
• String Formatting
• Memory Management
• Unix Logic
• Rigor
• Algorithms

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Overview

The ft_printf project is a recreation of the standard C library function printf. It was created to deepen understanding of variadic functions, string manipulation, and memory management. The project focuses on implementing core functionalities of printf, such as handling format specifiers like %c, %s, %p, %d, %i, %u, %x, %X, and %%. The unique aspect of this project is its emphasis on creating a well-structured and extensible codebase that can be integrated into future projects.

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Mandatory Features

• %c: Prints a single character.
• %s: Prints a string.
• %p: Prints a pointer address in hexadecimal format.
• %d: Prints a decimal (base 10) number.
• %i: Prints an integer in base 10.
• %u: Prints an unsigned decimal (base 10) number.
• %x: Prints a hexadecimal number (base 16) in lowercase.
• %X: Prints a hexadecimal number (base 16) in uppercase.
• %%: Prints a percent sign.

Bonus Features (not implemented)

The following bonus features were not implemented in this project but are part of the extended requirements for ft_printf:

• Flag Management: Handling flags like -, 0, ., and minimum field width for all conversions.
• Additional Flags: Support for #, +, and space flags to modify the output format (e.g., #x for hexadecimal with 0x prefix).
• Precision and Padding: Managing precision for numbers and strings, as well as padding with spaces or zeros.

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How to Use

Requirements

• CC compiler
• Make

1. Clone this repository:

   git clone [repository-url]  
   cd ft_printf  

2. Compile the project:

   make  

3. Use the ft_printf function in your code by including the header file at the top of the C File:

   #include "ft_printf.h"  

4. Make a program (with a main) to test the C Function ft_printf

Example Usage

Input Command	Description	Expected Output
ft_printf("Hello, %s!", "world")	Prints a string.	Hello, world!
ft_printf("Pointer: %p", &variable)	Prints a pointer address.	Pointer: 0x7ffee4b5c8d0
ft_printf("Number: %d", 42)	Prints a decimal number.	Number: 42
ft_printf("Hex: %x", 255)	Prints a hexadecimal number in lowercase.	Hex: ff
ft_printf("Percent sign: %%")	Prints a percent sign.	Percent sign: %

Error Handling

Input Command	Description	Expected Output
ft_printf("%z", 42)	Invalid format specifier.	No output or undefined behavior (depends on implementation).
ft_printf(NULL)	Passing a NULL format string.	Should handle without crashing.
ft_printf("%")	Incomplete format specifier.	Should return an error or handle gracefully.
ft_printf("%d", 2147483648)	Width or precision overflow (integer limit exceeded).	Should handle overflow or return an error.
ft_printf("%s", NULL)	NULL string passed as argument.	Should print (null) or handle it properly.
ft_printf("%p", NULL)	NULL pointer passed as argument.	Should print (nill) or handle it properly.
ft_printf("%c", 300)	Out-of-range character value for %c.	Should handle non-ASCII or return error.
ft_printf("%d", "string")	Incorrect argument type for %d.	Undefined behavior or possible crash.
ft_printf("%10$d", 42)	Incorrect position specifier.	Undefined behavior or controlled output (look at bonus)
ft_printf("%-010d", 42)	Conflicting flags (0 and - used together).	Should prioritize one or handle conflicts (look at bonus
ft_printf("%.*d", -5, 42)	Precision as a negative value.	Undefined behavior or handle negative precision (look at bonus)

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What I Learned

• Variadic Functions: Learned how to handle a variable number of arguments using va_start, va_arg, and va_end.
• String Formatting: Gained a deeper understanding of how format specifiers work and how to implement them.
• Memory Management: Improved skills in managing dynamic memory allocation and avoiding leaks.
• Rigor: Developed a disciplined approach to coding, ensuring adherence to strict standards and error-free execution.

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Author

• Name: Oliver King Zamora
• GitHub: oliverkingz
• 42 Login: ozamora-

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Acknowledgments

This project is part of the 42 Cursus, a rigorous programming curriculum that emphasizes hands-on learning and problem-solving. Special thanks to the 42 team for providing this challenging and rewarding project!

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