xv6-cs450/console.c
rsc 856e1fc1ad Attempt to clean up newproc somewhat.
Also remove all calls to memcpy in favor of
memmove, which has defined semantics when
the ranges overlap.  The fact that memcpy was
working in console.c to scroll the screen is not
guaranteed by all implementations.
2006-07-16 01:47:40 +00:00

159 lines
2.6 KiB
C

#include <types.h>
#include <x86.h>
#include "defs.h"
#include "spinlock.h"
struct spinlock console_lock;
int paniced = 0;
int use_console_lock = 0;
/*
* copy console output to parallel port, which you can tell
* .bochsrc to copy to the stdout:
* parport1: enabled=1, file="/dev/stdout"
*/
static void
lpt_putc(int c)
{
int i;
for (i = 0; !(inb(0x378+1) & 0x80) && i < 12800; i++)
;
outb(0x378+0, c);
outb(0x378+2, 0x08|0x04|0x01);
outb(0x378+2, 0x08);
}
static void
real_cons_putc(int c)
{
int crtport = 0x3d4; // io port of CGA
unsigned short *crt = (unsigned short *) 0xB8000; // base of CGA memory
int ind;
if(paniced){
cli();
while(1)
;
}
lpt_putc(c);
// cursor position, 16 bits, col + 80*row
outb(crtport, 14);
ind = inb(crtport + 1) << 8;
outb(crtport, 15);
ind |= inb(crtport + 1);
c &= 0xff;
if(c == '\n'){
ind -= (ind % 80);
ind += 80;
} else {
c |= 0x0700; // black on white
crt[ind] = c;
ind += 1;
}
if((ind / 80) >= 24){
// scroll up
memmove(crt, crt + 80, sizeof(crt[0]) * (23 * 80));
ind -= 80;
memset(crt + ind, 0, sizeof(crt[0]) * ((24 * 80) - ind));
}
outb(crtport, 14);
outb(crtport + 1, ind >> 8);
outb(crtport, 15);
outb(crtport + 1, ind);
}
void
cons_putc(int c)
{
if(use_console_lock)
acquire(&console_lock);
real_cons_putc(c);
if(use_console_lock)
release(&console_lock);
}
void
printint(int xx, int base, int sgn)
{
char buf[16];
char digits[] = "0123456789ABCDEF";
int i = 0, neg = 0;
unsigned int 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){
i -= 1;
real_cons_putc(buf[i]);
}
}
/*
* print to the console. only understands %d and %x.
*/
void
cprintf(char *fmt, ...)
{
int i, state = 0, c;
unsigned int *ap = (unsigned int *)(void*)&fmt + 1;
if(use_console_lock)
acquire(&console_lock);
for(i = 0; fmt[i]; i++){
c = fmt[i] & 0xff;
if(state == 0){
if(c == '%'){
state = '%';
} else {
real_cons_putc(c);
}
} else if(state == '%'){
if(c == 'd'){
printint(*ap, 10, 1);
ap++;
} else if(c == 'x' || c == 'p'){
printint(*ap, 16, 0);
ap++;
} else if(c == '%'){
real_cons_putc(c);
}
state = 0;
}
}
if(use_console_lock)
release(&console_lock);
}
void
panic(char *s)
{
__asm __volatile("cli");
use_console_lock = 0;
cprintf("panic: ");
cprintf(s, 0);
cprintf("\n", 0);
paniced = 1; // freeze other CPU
while(1)
;
}