printf.c

一个非常优秀的操作系统源代码

/* Gemini Nucleus
 *
 * $Id: printf.c,v 1.2 2000/04/04 09:03:38 verdich Exp $
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA. 
 */

#include <stdarg.h>
#include <types.h>
#include <debug/printf.h>
#include <debug/putchar.h>
#include <debug/puts.h>
#include <debug/putnumber.h>

int
aprintf(int a, const char *fmt, ...)
{
  va_list arg;
  int result;

  va_start(arg, fmt);
  result = avprintf(a, fmt, arg);
  va_end(arg);
  return result;
}

int
avprintf(int a, const char *fmt, va_list arg)
{
  char *str;
  uint32_t num; 

  for(; *fmt; fmt++)
    {
      if (*fmt != '%')
	{
	  aputchar(a, *fmt);
	  continue;
	}
      
      fmt++;
      switch(*fmt)
	{
	case 's':
	  str = va_arg(arg, char *);
	  aputs(a, str);
	  break;
	case 'x':
	  num = va_arg(arg, uint32_t);
	  aputnumber(a, num, 16, 8);
	  break;
	case 'd':
	  num = va_arg(arg, uint32_t);
	  aputnumber(a, num, 10, 0);
	  break;
	default:
	  /* ignore unsupported flags */
	  break;
	}
    }
  return 0;
}