ft_printf

A recreation of the standard C library's printf function.

Function prototypes:

int     ft_printf(const char *format, ...)

int     ft_dprintf(int fd, const char *format, ...)

Usage:

Like libc printf

Syntax for format specifiers:

%[flags][width][.precision][length]type

This implementation of printf supports the following:

Flags field #   (hash) 0   (zero)   (space) +   (plus) -   (minus)

Width field <number> *

Precision field .<number> .*

Length field hh h l ll j z

Type field d or i D o O u U x X p c C s S % b r

The format specifiers %b and %r are custom. They print unsigned int in binary and control characters, respectively.

Example:

#include "ft_printf.h"
#include <locale.h>

int    main(void)
{
    int i;

    setlocale(LC_ALL, "");
    ft_printf("Hello World!\n");
    ft_printf("%s", "This is ");
    ft_printf("%.*s\n", 9, "ft_printf and ft_dprintf");
    ft_printf("%d\n", 123);
    ft_printf("%05d\n", 42);
    ft_printf("%+09d\n", 42);
    ft_printf("%u\n", UINT_MAX);
    ft_printf("%#b\n", 256);
    ft_printf("%#o\n", 1039);
    ft_printf("%#X\n", 16417188);
    ft_printf("%p\n", &i);
    ft_printf("%C %C %C\n", L'ä', L'ö', L'ü');
    ft_printf("%S\n", L"🤗 💯 🌍 🚀 🔴 ");
    return (0);
}

Output:

Hello World!
This is ft_printf
123
00042
+00000042
4294967295
0b100000000
02017
0XFA81A4
0x7fff5c7159e8
ä ö ü
🤗 💯 🌍 🚀 🔴

Code snippet:

void    ft_process_string(const char *format, t_struct *f, va_list ap)
{
    while (format[f->i] != '\0')
    {
        if (format[f->i] == '%')
        {
            f->i++;
            if (ft_strchr("#-+ .*0123456789hljz", format[f->i]))
                ft_parse_modifiers(format, f, ap);
            if (ft_strchr("sSpdDioOuUxXcCbr%", format[f->i]))
            {
                ft_print(format, f, ap);
                if (f->len == -1)
                    return ;
                ft_reset_struct(f);
            }
        }
        else
            f->len += write(f->fd, &format[f->i], 1);
        f->i++;
    }
}

Subject