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#include <stdarg.h>
#include "types.h"
#include "param.h"
#include "spinlock.h"
#include "sleeplock.h"
#include "fs.h"
#include "file.h"
#include "riscv.h"
#include "defs.h"
static char digits[] = "0123456789abcdef";
static int
sputc(char *s, char c)
{
*s = c;
return 1;
}
static int
sprintint(char *s, int xx, int base, int sign)
{
char buf[16];
int i, n;
uint x;
if(sign && (sign = xx < 0))
x = -xx;
else
x = xx;
i = 0;
do {
buf[i++] = digits[x % base];
} while((x /= base) != 0);
if(sign)
buf[i++] = '-';
n = 0;
while(--i >= 0)
n += sputc(s+n, buf[i]);
return n;
}
int
snprintf(char *buf, int sz, char *fmt, ...)
{
va_list ap;
int i, c;
int off = 0;
char *s;
if (fmt == 0)
panic("null fmt");
va_start(ap, fmt);
for(i = 0; off < sz && (c = fmt[i] & 0xff) != 0; i++){
if(c != '%'){
off += sputc(buf+off, c);
continue;
}
c = fmt[++i] & 0xff;
if(c == 0)
break;
switch(c){
case 'd':
off += sprintint(buf+off, va_arg(ap, int), 10, 1);
break;
case 'x':
off += sprintint(buf+off, va_arg(ap, int), 16, 1);
break;
case 's':
if((s = va_arg(ap, char*)) == 0)
s = "(null)";
for(; *s && off < sz; s++)
off += sputc(buf+off, *s);
break;
case '%':
off += sputc(buf+off, '%');
break;
default:
// Print unknown % sequence to draw attention.
off += sputc(buf+off, '%');
off += sputc(buf+off, c);
break;
}
}
return off;
}
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