xv6-riscv/kernel/printf.c
Robert Morris dd2574bc10 tell gcc to check printf format strings
add %ld %lld %u %lu %llu %lx %llx to kernel and user printf
2023-12-31 12:21:46 -05:00

178 lines
3.3 KiB
C

//
// formatted console output -- printf, panic.
//
#include <stdarg.h>
#include "types.h"
#include "param.h"
#include "spinlock.h"
#include "sleeplock.h"
#include "fs.h"
#include "file.h"
#include "memlayout.h"
#include "riscv.h"
#include "defs.h"
#include "proc.h"
volatile int panicked = 0;
// lock to avoid interleaving concurrent printf's.
static struct {
struct spinlock lock;
int locking;
} pr;
static char digits[] = "0123456789abcdef";
static void
printint(long long xx, int base, int sign)
{
char buf[16];
int i;
unsigned long long 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++] = '-';
while(--i >= 0)
consputc(buf[i]);
}
static void
printptr(uint64 x)
{
int i;
consputc('0');
consputc('x');
for (i = 0; i < (sizeof(uint64) * 2); i++, x <<= 4)
consputc(digits[x >> (sizeof(uint64) * 8 - 4)]);
}
// Print to the console.
int
printf(char *fmt, ...)
{
va_list ap;
int i, cx, c0, c1, c2, locking;
char *s;
locking = pr.locking;
if(locking)
acquire(&pr.lock);
va_start(ap, fmt);
for(i = 0; (cx = fmt[i] & 0xff) != 0; i++){
if(cx != '%'){
consputc(cx);
continue;
}
i++;
c0 = fmt[i+0] & 0xff;
c1 = c2 = 0;
if(c0) c1 = fmt[i+1] & 0xff;
if(c1) c2 = fmt[i+2] & 0xff;
if(c0 == 'd'){
printint(va_arg(ap, int), 10, 1);
} else if(c0 == 'l' && c1 == 'd'){
printint(va_arg(ap, uint64), 10, 1);
i += 1;
} else if(c0 == 'l' && c1 == 'l' && c2 == 'd'){
printint(va_arg(ap, uint64), 10, 1);
i += 2;
} else if(c0 == 'u'){
printint(va_arg(ap, int), 10, 0);
} else if(c0 == 'l' && c1 == 'u'){
printint(va_arg(ap, uint64), 10, 0);
i += 1;
} else if(c0 == 'l' && c1 == 'l' && c2 == 'u'){
printint(va_arg(ap, uint64), 10, 0);
i += 2;
} else if(c0 == 'x'){
printint(va_arg(ap, int), 16, 0);
} else if(c0 == 'l' && c1 == 'x'){
printint(va_arg(ap, uint64), 16, 0);
i += 1;
} else if(c0 == 'l' && c1 == 'l' && c2 == 'x'){
printint(va_arg(ap, uint64), 16, 0);
i += 2;
} else if(c0 == 'p'){
printptr(va_arg(ap, uint64));
} else if(c0 == 's'){
if((s = va_arg(ap, char*)) == 0)
s = "(null)";
for(; *s; s++)
consputc(*s);
} else if(c0 == '%'){
consputc('%');
} else if(c0 == 0){
break;
} else {
// Print unknown % sequence to draw attention.
consputc('%');
consputc(c0);
}
#if 0
switch(c){
case 'd':
printint(va_arg(ap, int), 10, 1);
break;
case 'x':
printint(va_arg(ap, int), 16, 1);
break;
case 'p':
printptr(va_arg(ap, uint64));
break;
case 's':
if((s = va_arg(ap, char*)) == 0)
s = "(null)";
for(; *s; s++)
consputc(*s);
break;
case '%':
consputc('%');
break;
default:
// Print unknown % sequence to draw attention.
consputc('%');
consputc(c);
break;
}
#endif
}
va_end(ap);
if(locking)
release(&pr.lock);
return 0;
}
void
panic(char *s)
{
pr.locking = 0;
printf("panic: ");
printf("%s\n", s);
panicked = 1; // freeze uart output from other CPUs
for(;;)
;
}
void
printfinit(void)
{
initlock(&pr.lock, "pr");
pr.locking = 1;
}