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#include <u.h>
#include <libc.h>
#include <thread.h>
#include "dat.h"
#include "fns.h"
Channel *telnetrxch, *telnettxch;
extern Channel *uartrxch, *uarttxch;
int teldebug;
enum {
SE = 240,
NOP = 241,
BRK = 243,
IP = 244,
AO = 245,
AYT = 246,
EC = 247,
EL = 248,
GA = 249,
SB = 250,
WILL = 251,
WONT = 252,
DO = 253,
DONT = 254,
IAC = 255,
XMITBIN = 0,
ECHO = 1,
SUPRGA = 3,
LINEEDIT = 34,
};
int telfd;
static void
netrproc(void *)
{
static uchar buf[512];
int n, c;
uchar *p;
for(;;){
n = read(telfd, buf, sizeof(buf));
if(n < 0) sysfatal("read: %r");
for(p = buf; p < buf + n; p++){
c = *p;
send(telnetrxch, &c);
}
}
}
static void
netwproc(void *)
{
static uchar buf[512];
int c;
uchar *p;
for(;;){
recv(telnettxch, &c);
p = buf;
do
*p++ = c;
while(nbrecv(telnettxch, &c) > 0);
if(write(telfd, buf, p - buf) < p - buf)
sysfatal("write: %r");
}
}
static void
telnetrthread(void *)
{
int c;
for(;;){
recv(telnetrxch, &c);
if(c != IAC){
send(uartrxch, &c);
continue;
}
recv(telnetrxch, &c);
switch(c){
case NOP: break;
case WILL:
recv(telnetrxch, &c);
if(teldebug) fprint(2, "WILL %d\n", c);
break;
case WONT:
recv(telnetrxch, &c);
if(teldebug) fprint(2, "WONT %d\n", c);
break;
case DO:
recv(telnetrxch, &c);
if(teldebug) fprint(2, "DO %d\n", c);
break;
case DONT:
recv(telnetrxch, &c);
if(teldebug) fprint(2, "DONT %d\n", c);
break;
case IAC:
send(uartrxch, &c);
break;
default:
fprint(2, "unknown telnet command %d\n", c);
}
}
}
static void
cmd(int a, int b)
{
send(telnettxch, &a);
if(b >= 0) send(telnettxch, &b);
}
static void
telnetwthread(void *)
{
int c;
for(;;){
recv(uarttxch, &c);
send(telnettxch, &c);
if(c == 0xff)
send(telnettxch, &c);
}
}
void
telnetinit(char *dialstr)
{
telfd = dial(netmkaddr(dialstr, nil, "telnet"), nil, nil, nil);
if(telfd < 0) sysfatal("dial: %r");
telnetrxch = chancreate(sizeof(int), 128);
telnettxch = chancreate(sizeof(int), 128);
cmd(WILL, XMITBIN);
cmd(DO, XMITBIN);
cmd(DONT, ECHO);
cmd(DO, SUPRGA);
cmd(WILL, SUPRGA);
cmd(WONT, LINEEDIT);
cmd(DONT, LINEEDIT);
proccreate(netrproc, nil, mainstacksize);
proccreate(netwproc, nil, mainstacksize);
threadcreate(telnetrthread, nil, mainstacksize);
threadcreate(telnetwthread, nil, mainstacksize);
}
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