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#include "types.h"
#include "stat.h"
#include "user.h"
static void
putc(int fd, char c)
{
write(fd, &c, 1);
}
static void
printint(int fd, int xx, int base, int sgn)
{
char buf[16];
char digits[] = "0123456789ABCDEF";
int i = 0, neg = 0;
uint x;
if(sgn && xx < 0){
neg = 1;
x = 0 - xx;
} else {
x = xx;
}
do {
buf[i++] = digits[x % base];
} while((x /= base) != 0);
if(neg)
buf[i++] = '-';
while(--i >= 0)
putc(fd, buf[i]);
}
// Print to the given fd. Only understands %d, %x, %p, %s.
void
printf(int fd, char *fmt, ...)
{
int i, state = 0, c;
uint *ap = (uint*)(void*)&fmt + 1;
for(i = 0; fmt[i]; i++){
c = fmt[i] & 0xff;
if(state == 0){
if(c == '%'){
state = '%';
} else {
putc(fd, c);
}
} else if(state == '%'){
if(c == 'd'){
printint(fd, *ap, 10, 1);
ap++;
} else if(c == 'x' || c == 'p'){
printint(fd, *ap, 16, 0);
ap++;
} else if(c == 's'){
char *s = (char*)*ap;
ap++;
while(*s != 0){
putc(fd, *s);
s++;
}
} else if(c == 'c'){
putc(fd, *ap);
ap++;
} else if(c == '%'){
putc(fd, c);
} else {
// Unknown % sequence. Print it to draw attention.
putc(fd, '%');
putc(fd, c);
}
state = 0;
}
}
}
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