lib/stdio/printf.c


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#include <stdarg.h>
#include <stdio.h>

#include <devices/uart_16550.h>

int
printf(const char *restrict format, ...)
{
  int written = 0;
  va_list params;
  va_start(params, format);

  int s = 0;
  int l = 0;
  for (int i = 0; format[i] != '\0'; ++i) {
    if (format[i] == '%') {
      written += uart_puts(COM1, &format[s], l);
      s = i + 2;
      ++i;

      switch (format[i]) {
      case 's':
        written += uart_puts(COM1, va_arg(params, const char *), -1);
        break;
      }

      l = 0;
    }

    else
      ++l;
  }

  if (l > 0) written += uart_puts(COM1, &format[s], l);

  va_end(params);
  return written;
}