add EOF handling to console_read - works with cat

This commit is contained in:
rsc 2007-08-08 08:04:02 +00:00
parent ca3d577671
commit 07018064bb

View file

@ -316,7 +316,7 @@ static uchar *charcode[4] = {
};
#define KBD_BUF 64
char kbd_buf[KBD_BUF];
uchar kbd_buf[KBD_BUF];
int kbd_r;
int kbd_w;
struct spinlock kbd_lock;
@ -389,24 +389,29 @@ out:
int
console_read(int minor, char *dst, int n)
{
uint target = n;
uint target;
int c;
target = n;
acquire(&kbd_lock);
while(kbd_w == kbd_r) {
while(n > 0){
while(kbd_r == kbd_w)
sleep(&kbd_r, &kbd_lock);
c = kbd_buf[kbd_r++];
if(c == C('D')){ // EOF
if(n < target){
// Save ^D for next time, to make sure
// caller gets a 0-byte result.
kbd_r--;
}
while(n > 0 && kbd_w != kbd_r){
*dst = (kbd_buf[kbd_r]) & 0xff;
cons_putc(*dst & 0xff);
dst++;
break;
}
*dst++ = c;
cons_putc(c);
--n;
kbd_r++;
if(kbd_r >= KBD_BUF)
kbd_r = 0;
}
release(&kbd_lock);
return target - n;