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#include "printf.h"
#include "types.h"
#include "portio.h"
void putchar(char c) {
if(c == '\n') {
outb(0x3f8, '\r');
}
outb(0x3f8, c);
}
int printf(const char* format, ...) {
int32_t* argp = (int32_t*)&format;
int num;
while(*format) {
if(*format != '%') {
putchar(*format++);
num++;
continue;
}
format++;
bool is_signed = false;
bool zero_pad = false;
int radix = 16;
int min_len = 0;
if(*format == '0') {
zero_pad = true;
}
while(*format >= '0' && *format <= '9') {
min_len = min_len * 10 + *format++ - '0';
}
switch(*format++) {
case '%':
putchar('%');
num++;
break;
case 'c':
putchar((char)*++argp);
num++;
break;
case 's':
;
char* str = (char*)*++argp;
while(*str) {
putchar(*str++);
num++;
}
break;
case 'd':
is_signed = true;
case 'u':
radix = 10;
case 'x':
;
uint32_t x = (uint32_t)*(++argp);
if(is_signed && (int32_t)x < 0) {
x = -x;
putchar('-');
min_len--;
}
char buf[11];
char* bufp = &buf[sizeof(buf)];
*--bufp = 0;
do {
int d = x % radix;
*--bufp = d < 10 ? '0' + d : 'a' - 10 + d;
x /= radix;
min_len--;
} while(x);
while(min_len > 0) {
putchar(zero_pad ? '0' : ' ');
num++;
min_len--;
}
while(*bufp) {
putchar(*bufp++);
num++;
}
break;
}
}
return num;
}
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