printf/_printf.c at master · UK-83/printf · GitHub

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#include "main.h"

/**
 * _printf - Produces output according to a format.
 * @format: Character string containing directives.
 *
 * Return: Number of characters printed.
 */
int _printf(const char *format, ...)
{
	va_list args;
	int printed_chars = 0;
	int num, temp, len;
	char buffer[11];
	int i;
	char ch;
	char *str;

	va_start(args, format);

	while (*format)
	{
		if (*format == '%')
		{
			format++;

			switch (*format)
			{
				case 'c':
					ch = (char) va_arg(args, int);
					write(1, &ch, 1);
					printed_chars++;
					break;

				case 's':
					str = va_arg(args, char *);
					while (*str)
					{
						write(1, str, 1);
						str++;
						printed_chars++;
					}
					break;

				case 'd':
				case 'i':
					num = va_arg(args, int);
					len = 0;
					if (num < 0)
					{
						write(1, "-", 1);
						printed_chars++;
						num *= -1;
					}
					temp = num;
					do {
						temp /= 10;
						len++;
					} while (temp != 0);
					for (i = len - 1; i >= 0; i--)
					{
						buffer[i] = (num % 10) + '0';
						num /= 10;
					}
					write(1, buffer, len);
					printed_chars += len;
					break;

				case '%':
					write(1, "%", 1);
					printed_chars++;
					break;

				default:
					write(1, "%", 1);
					write(1, format, 1);
					printed_chars += 2;
					break;
			}
		}
		else
		{
			write(1, format, 1);
			printed_chars++;
		}

		format++;
	}

	va_end(args);

	return (printed_chars);
}