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#include <stdarg.h>
#include <stdbool.h>
#include "uart.h"
static int print_decimal(unsigned long val)
{
char buf[32];
char *p = buf+31;
*p = 0;
if (val == 0)
*--p = '0';
else
{
do
{
unsigned long d, r;
/* Compiling with -Os results in a call to the division routine.
Do what the compiler ought to have done. */
d = __builtin_alpha_umulh(val, 0xcccccccccccccccd);
d >>= 3;
r = val - (d * 10);
*--p = r + '0';
val = d;
}
while (val);
}
uart_puts(COM1, p+1);
return sizeof(buf) - (p - buf);
}
static int print_hex(unsigned long val)
{
char buf[32];
char *p = buf+31;
*p = 0;
if (val == 0)
*--p = '0';
else
{
do
{
int d = val % 16;
*--p = (d < 10 ? '0' : 'a' - 10) + d;
val /= 16;
}
while (val);
}
uart_puts(COM1, p+1);
return sizeof(buf) - (p - buf);
}
int printf(const char *fmt, ...)
{
va_list args;
unsigned long val;
int r = 0;
va_start(args, fmt);
for (; *fmt ; fmt++)
if (*fmt != '%')
{
uart_putchar(COM1, *fmt);
r++;
}
else
{
bool is_long = false;
restart:
switch (*++fmt)
{
case '%':
uart_putchar(COM1, '%');
r++;
break;
case 'l':
is_long = true;
goto restart;
case 'd':
if (is_long)
{
long d = va_arg (args, long);
if (d < 0)
{
uart_putchar(COM1, '-');
d = -d;
}
val = d;
}
else
{
int d = va_arg (args, int);
if (d < 0)
{
uart_putchar(COM1, '-');
d = -d;
r++;
}
val = d;
}
goto do_unsigned;
case 'u':
if (is_long)
val = va_arg (args, unsigned long);
else
val = va_arg (args, unsigned int);
do_unsigned:
r += print_decimal (val);
break;
case 'x':
if (is_long)
val = va_arg (args, unsigned long);
else
val = va_arg (args, unsigned int);
r += print_hex (val);
case 's':
{
const char *s = va_arg (args, const char *);
while (*s)
{
uart_putchar(COM1, *s++);
r++;
}
break;
}
default:
uart_putchar(COM1, '%');
uart_putchar(COM1, *fmt);
r += 2;
break;
}
}
va_end(args);
return r;
}
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