printf/_printf.c at master · Kurume98/printf · GitHub

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#include "main.h"

int _printf(const char *format, ...)
{
    va_list list;
    int len;
    int printed_chars = 0;
    va_start(list, format);

    if (format == NULL)
        return -1;

    while (*format)
    {
        if (*format == '%' && *(format + 1) != '\0')
        {
            format++;

            switch (*format)
           {
                case 'c':
                {
                    char c = va_arg(list, int);
                    write(1, &c, 1);
                    printed_chars++;
                    break;
                }
                case 's':
                {
                    char *str = va_arg(list, char *);
                    if (str == NULL)
                        str = "(null)";
                    len = 0; /* Initialize len here */
                    while (str[len])
                        len++;
                    write(1, str, len);
                    printed_chars += len;
                    break;
                }
                case '%':
                    write(1, "%", 1);
                    printed_chars++;
                    break;
            }
        }
        else
        {
            write(1, format, 1);
            printed_chars++;
        }

        format++;
    }

    va_end(list);
    return printed_chars;
}