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/*
* Copyright (c) 2013 Kevin Wolf <kwolf@redhat.com>
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "libc.h"
static void print_char(char c)
{
outb(0xe9, c);
}
static void print_str(char *s)
{
while (*s) {
print_char(*s++);
}
}
static void print_num(uint64_t value, int base)
{
char digits[] = "0123456789abcdef";
char buf[32] = { 0 };
int i = sizeof(buf) - 2;
do {
buf[i--] = digits[value % base];
value /= base;
} while (value);
print_str(&buf[i + 1]);
}
void printf(const char *fmt, ...)
{
va_list ap;
uint64_t val;
char *str;
int base;
int has_long;
int alt_form;
va_start(ap, fmt);
for (; *fmt; fmt++) {
if (*fmt != '%') {
print_char(*fmt);
continue;
}
fmt++;
if (*fmt == '#') {
fmt++;
alt_form = 1;
} else {
alt_form = 0;
}
if (*fmt == 'l') {
fmt++;
if (*fmt == 'l') {
fmt++;
has_long = 2;
} else {
has_long = 1;
}
} else {
has_long = 0;
}
switch (*fmt) {
case 'x':
case 'p':
base = 16;
goto convert_number;
case 'd':
case 'i':
case 'u':
base = 10;
goto convert_number;
case 'o':
base = 8;
goto convert_number;
convert_number:
switch (has_long) {
case 0:
val = va_arg(ap, unsigned int);
break;
case 1:
val = va_arg(ap, unsigned long);
break;
case 2:
val = va_arg(ap, unsigned long long);
break;
}
if (alt_form && base == 16) {
print_str("0x");
}
print_num(val, base);
break;
case 's':
str = va_arg(ap, char*);
print_str(str);
break;
case '%':
print_char(*fmt);
break;
default:
print_char('%');
print_char(*fmt);
break;
}
}
va_end(ap);
}
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