Source to kern/tty.c
/*-
* Copyright (c) 1982, 1986, 1990 The Regents of the University of California.
* Copyright (c) 1991 The Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the University of
* California, Berkeley and its contributors.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* @(#)tty.c 7.44 (Berkeley) 5/28/91
*/
static char rcsid[] = "$Header: /usr/bill/working/sys/kern/RCS/tty.c,v 1.3 92/01/21 21:31:11 william Exp $";
#include "param.h"
#include "systm.h"
#include "ioctl.h"
#define TTYDEFCHARS
#include "tty.h"
#undef TTYDEFCHARS
#include "proc.h"
#include "file.h"
#include "conf.h"
#include "dkstat.h"
#include "uio.h"
#include "kernel.h"
#include "vnode.h"
#include "syslog.h"
#include "vm/vm.h"
static int proc_compare __P((struct proc *p1, struct proc *p2));
/* symbolic sleep message strings */
char ttyin[] = "ttyin";
char ttyout[] = "ttyout";
char ttopen[] = "ttyopn";
char ttclos[] = "ttycls";
char ttybg[] = "ttybg";
char ttybuf[] = "ttybuf";
/*
* Table giving parity for characters and indicating
* character classes to tty driver. The 8th bit
* indicates parity, the 7th bit indicates the character
* is an alphameric or underscore (for ALTWERASE), and the
* low 6 bits indicate delay type. If the low 6 bits are 0
* then the character needs no special processing on output;
* classes other than 0 might be translated or (not currently)
* require delays.
*/
#define PARITY(c) (partab[c] & 0x80)
#define ISALPHA(c) (partab[(c)&TTY_CHARMASK] & 0x40)
#define CCLASSMASK 0x3f
#define CCLASS(c) (partab[c] & CCLASSMASK)
#define E 0x00 /* even parity */
#define O 0x80 /* odd parity */
#define ALPHA 0x40 /* alpha or underscore */
#define NO ORDINARY
#define NA ORDINARY|ALPHA
#define CC CONTROL
#define BS BACKSPACE
#define NL NEWLINE
#define TB TAB
#define VT VTAB
#define CR RETURN
char partab[] = {
E|CC, O|CC, O|CC, E|CC, O|CC, E|CC, E|CC, O|CC, /* nul - bel */
O|BS, E|TB, E|NL, O|CC, E|VT, O|CR, O|CC, E|CC, /* bs - si */
O|CC, E|CC, E|CC, O|CC, E|CC, O|CC, O|CC, E|CC, /* dle - etb */
E|CC, O|CC, O|CC, E|CC, O|CC, E|CC, E|CC, O|CC, /* can - us */
O|NO, E|NO, E|NO, O|NO, E|NO, O|NO, O|NO, E|NO, /* sp - ' */
E|NO, O|NO, O|NO, E|NO, O|NO, E|NO, E|NO, O|NO, /* ( - / */
E|NA, O|NA, O|NA, E|NA, O|NA, E|NA, E|NA, O|NA, /* 0 - 7 */
O|NA, E|NA, E|NO, O|NO, E|NO, O|NO, O|NO, E|NO, /* 8 - ? */
O|NO, E|NA, E|NA, O|NA, E|NA, O|NA, O|NA, E|NA, /* @ - G */
E|NA, O|NA, O|NA, E|NA, O|NA, E|NA, E|NA, O|NA, /* H - O */
E|NA, O|NA, O|NA, E|NA, O|NA, E|NA, E|NA, O|NA, /* P - W */
O|NA, E|NA, E|NA, O|NO, E|NO, O|NO, O|NO, O|NA, /* X - _ */
E|NO, O|NA, O|NA, E|NA, O|NA, E|NA, E|NA, O|NA, /* ` - g */
O|NA, E|NA, E|NA, O|NA, E|NA, O|NA, O|NA, E|NA, /* h - o */
O|NA, E|NA, E|NA, O|NA, E|NA, O|NA, O|NA, E|NA, /* p - w */
E|NA, O|NA, O|NA, E|NO, O|NO, E|NO, E|NO, O|CC, /* x - del */
/*
* "meta" chars; should be settable per charset.
* For now, treat all as normal characters.
*/
NA, NA, NA, NA, NA, NA, NA, NA,
NA, NA, NA, NA, NA, NA, NA, NA,
NA, NA, NA, NA, NA, NA, NA, NA,
NA, NA, NA, NA, NA, NA, NA, NA,
NA, NA, NA, NA, NA, NA, NA, NA,
NA, NA, NA, NA, NA, NA, NA, NA,
NA, NA, NA, NA, NA, NA, NA, NA,
NA, NA, NA, NA, NA, NA, NA, NA,
NA, NA, NA, NA, NA, NA, NA, NA,
NA, NA, NA, NA, NA, NA, NA, NA,
NA, NA, NA, NA, NA, NA, NA, NA,
NA, NA, NA, NA, NA, NA, NA, NA,
NA, NA, NA, NA, NA, NA, NA, NA,
NA, NA, NA, NA, NA, NA, NA, NA,
NA, NA, NA, NA, NA, NA, NA, NA,
NA, NA, NA, NA, NA, NA, NA, NA,
};
#undef NO
#undef NA
#undef CC
#undef BS
#undef NL
#undef TB
#undef VT
#undef CR
extern struct tty *constty; /* temporary virtual console */
/*
* Is 'c' a line delimiter ("break" character)?
*/
#define ttbreakc(c) ((c) == '\n' || ((c) == cc[VEOF] || \
(c) == cc[VEOL] || (c) == cc[VEOL2]) && (c) != _POSIX_VDISABLE)
ttychars(tp)
struct tty *tp;
{
bcopy(ttydefchars, tp->t_cc, sizeof(ttydefchars));
}
/*
* Flush tty after output has drained.
*/
ttywflush(tp)
struct tty *tp;
{
int error;
if ((error = ttywait(tp)) == 0)
ttyflush(tp, FREAD);
return (error);
}
/*
* Wait for output to drain.
*/
ttywait(tp)
register struct tty *tp;
{
int error = 0, s = spltty();
while ((RB_LEN(&tp->t_out) || tp->t_state&TS_BUSY) &&
(tp->t_state&TS_CARR_ON || tp->t_cflag&CLOCAL) &&
tp->t_oproc) {
(*tp->t_oproc)(tp);
tp->t_state |= TS_ASLEEP;
if (error = ttysleep(tp, (caddr_t)&tp->t_out,
TTOPRI | PCATCH, ttyout, 0))
break;
}
splx(s);
return (error);
}
#define flushq(qq) { \
register struct ringb *r = qq; \
r->rb_hd = r->rb_tl; \
}
/*
* Flush TTY read and/or write queues,
* notifying anyone waiting.
*/
ttyflush(tp, rw)
register struct tty *tp;
{
register s;
s = spltty();
if (rw & FREAD) {
flushq(&tp->t_can);
flushq(&tp->t_raw);
tp->t_rocount = 0;
tp->t_rocol = 0;
tp->t_state &= ~TS_LOCAL;
ttwakeup(tp);
}
if (rw & FWRITE) {
tp->t_state &= ~TS_TTSTOP;
(*cdevsw[major(tp->t_dev)].d_stop)(tp, rw);
flushq(&tp->t_out);
wakeup((caddr_t)&tp->t_out);
if (tp->t_wsel) {
selwakeup(tp->t_wsel, tp->t_state & TS_WCOLL);
tp->t_wsel = 0;
tp->t_state &= ~TS_WCOLL;
}
}
splx(s);
}
/*
* Send stop character on input overflow.
*/
ttyblock(tp)
register struct tty *tp;
{
register x;
int rawcc, cancc;
rawcc = RB_LEN(&tp->t_raw);
cancc = RB_LEN(&tp->t_can);
x = rawcc + cancc;
if (rawcc > TTYHOG) {
ttyflush(tp, FREAD|FWRITE);
tp->t_state &= ~TS_TBLOCK;
}
/*
* Block further input iff:
* Current input > threshold AND input is available to user program
*/
if (x >= TTYHOG/2 && (tp->t_state & TS_TBLOCK) == 0 &&
((tp->t_lflag&ICANON) == 0) || (cancc > 0) &&
tp->t_cc[VSTOP] != _POSIX_VDISABLE) {
if (putc(tp->t_cc[VSTOP], &tp->t_out) == 0) {
tp->t_state |= TS_TBLOCK;
ttstart(tp);
}
}
}
ttstart(tp)
struct tty *tp;
{
if (tp->t_oproc) /* kludge for pty */
(*tp->t_oproc)(tp);
}
ttrstrt(tp) /* XXX */
struct tty *tp;
{
#ifdef DIAGNOSTIC
if (tp == 0)
panic("ttrstrt");
#endif
tp->t_state &= ~TS_TIMEOUT;
ttstart(tp);
}
/*
* Common code for ioctls on tty devices.
* Called after line-discipline-specific ioctl
* has been called to do discipline-specific functions
* and/or reject any of these ioctl commands.
*/
/*ARGSUSED*/
ttioctl(tp, com, data, flag)
register struct tty *tp;
caddr_t data;
{
register struct proc *p = curproc; /* XXX */
extern int nldisp;
int s, error;
/*
* If the ioctl involves modification,
* hang if in the background.
*/
switch (com) {
case TIOCSETD:
case TIOCFLUSH:
/*case TIOCSPGRP:*/
case TIOCSTI:
case TIOCSWINSZ:
case TIOCSETA:
case TIOCSETAW:
case TIOCSETAF:
#ifdef COMPAT_43
case TIOCSETP:
case TIOCSETN:
case TIOCSETC:
case TIOCSLTC:
case TIOCLBIS:
case TIOCLBIC:
case TIOCLSET:
case OTIOCSETD:
#endif
while (isbackground(curproc, tp) &&
p->p_pgrp->pg_jobc && (p->p_flag&SPPWAIT) == 0 &&
(p->p_sigignore & sigmask(SIGTTOU)) == 0 &&
(p->p_sigmask & sigmask(SIGTTOU)) == 0) {
pgsignal(p->p_pgrp, SIGTTOU, 1);
if (error = ttysleep(tp, (caddr_t)&lbolt,
TTOPRI | PCATCH, ttybg, 0))
return (error);
}
break;
}
/*
* Process the ioctl.
*/
switch (com) {
/* get discipline number */
case TIOCGETD:
*(int *)data = tp->t_line;
break;
/* set line discipline */
case TIOCSETD: {
register int t = *(int *)data;
dev_t dev = tp->t_dev;
if ((unsigned)t >= nldisp)
return (ENXIO);
if (t != tp->t_line) {
s = spltty();
(*linesw[tp->t_line].l_close)(tp, flag);
error = (*linesw[t].l_open)(dev, tp);
if (error) {
(void)(*linesw[tp->t_line].l_open)(dev, tp);
splx(s);
return (error);
}
tp->t_line = t;
splx(s);
}
break;
}
/* prevent more opens on channel */
case TIOCEXCL:
tp->t_state |= TS_XCLUDE;
break;
case TIOCNXCL:
tp->t_state &= ~TS_XCLUDE;
break;
case TIOCHPCL:
tp->t_cflag |= HUPCL;
break;
case TIOCFLUSH: {
register int flags = *(int *)data;
if (flags == 0)
flags = FREAD|FWRITE;
else
flags &= FREAD|FWRITE;
ttyflush(tp, flags);
break;
}
case FIOASYNC:
if (*(int *)data)
tp->t_state |= TS_ASYNC;
else
tp->t_state &= ~TS_ASYNC;
break;
case FIONBIO:
break; /* XXX remove */
/* return number of characters immediately available */
case FIONREAD:
*(off_t *)data = ttnread(tp);
break;
case TIOCOUTQ:
*(int *)data = RB_LEN(&tp->t_out);
break;
case TIOCSTOP:
s = spltty();
if ((tp->t_state&TS_TTSTOP) == 0) {
tp->t_state |= TS_TTSTOP;
(*cdevsw[major(tp->t_dev)].d_stop)(tp, 0);
}
splx(s);
break;
case TIOCSTART:
s = spltty();
if ((tp->t_state&TS_TTSTOP) || (tp->t_lflag&FLUSHO)) {
tp->t_state &= ~TS_TTSTOP;
tp->t_lflag &= ~FLUSHO;
ttstart(tp);
}
splx(s);
break;
/*
* Simulate typing of a character at the terminal.
*/
case TIOCSTI:
if (p->p_ucred->cr_uid && (flag & FREAD) == 0)
return (EPERM);
if (p->p_ucred->cr_uid && !isctty(p, tp))
return (EACCES);
(*linesw[tp->t_line].l_rint)(*(char *)data, tp);
break;
case TIOCGETA: {
struct termios *t = (struct termios *)data;
bcopy(&tp->t_termios, t, sizeof(struct termios));
break;
}
case TIOCSETA:
case TIOCSETAW:
case TIOCSETAF: {
register struct termios *t = (struct termios *)data;
s = spltty();
if (com == TIOCSETAW || com == TIOCSETAF) {
if (error = ttywait(tp)) {
splx(s);
return (error);
}
if (com == TIOCSETAF)
ttyflush(tp, FREAD);
}
if ((t->c_cflag&CIGNORE) == 0) {
/*
* set device hardware
*/
if (tp->t_param && (error = (*tp->t_param)(tp, t))) {
splx(s);
return (error);
} else {
if ((tp->t_state&TS_CARR_ON) == 0 &&
(tp->t_cflag&CLOCAL) &&
(t->c_cflag&CLOCAL) == 0) {
tp->t_state &= ~TS_ISOPEN;
tp->t_state |= TS_WOPEN;
ttwakeup(tp);
}
tp->t_cflag = t->c_cflag;
tp->t_ispeed = t->c_ispeed;
tp->t_ospeed = t->c_ospeed;
}
ttsetwater(tp);
}
if (com != TIOCSETAF) {
if ((t->c_lflag&ICANON) != (tp->t_lflag&ICANON))
if (t->c_lflag&ICANON) {
tp->t_lflag |= PENDIN;
ttwakeup(tp);
}
else {
/*struct ringb tb;*/
catb(&tp->t_raw, &tp->t_can);
catb(&tp->t_can, &tp->t_raw);
/*tb = tp->t_raw;
tp->t_raw = tp->t_can;
tp->t_can = tb;*/
}
}
tp->t_iflag = t->c_iflag;
tp->t_oflag = t->c_oflag;
/*
* Make the EXTPROC bit read only.
*/
if (tp->t_lflag&EXTPROC)
t->c_lflag |= EXTPROC;
else
t->c_lflag &= ~EXTPROC;
tp->t_lflag = t->c_lflag;
bcopy(t->c_cc, tp->t_cc, sizeof(t->c_cc));
splx(s);
break;
}
/*
* Set controlling terminal.
* Session ctty vnode pointer set in vnode layer.
*/
case TIOCSCTTY:
if (!SESS_LEADER(p) ||
(p->p_session->s_ttyvp || tp->t_session) &&
(tp->t_session != p->p_session))
return (EPERM);
tp->t_session = p->p_session;
tp->t_pgrp = p->p_pgrp;
p->p_session->s_ttyp = tp;
p->p_flag |= SCTTY;
break;
/*
* Set terminal process group.
*/
case TIOCSPGRP: {
register struct pgrp *pgrp = pgfind(*(int *)data);
if (!isctty(p, tp))
return (ENOTTY);
else if (pgrp == NULL || pgrp->pg_session != p->p_session)
return (EPERM);
tp->t_pgrp = pgrp;
break;
}
case TIOCGPGRP:
if (!isctty(p, tp))
return (ENOTTY);
*(int *)data = tp->t_pgrp ? tp->t_pgrp->pg_id : NO_PID;
break;
case TIOCSWINSZ:
if (bcmp((caddr_t)&tp->t_winsize, data,
sizeof (struct winsize))) {
tp->t_winsize = *(struct winsize *)data;
pgsignal(tp->t_pgrp, SIGWINCH, 1);
}
break;
case TIOCGWINSZ:
*(struct winsize *)data = tp->t_winsize;
break;
case TIOCCONS:
if (*(int *)data) {
if (constty && constty != tp &&
(constty->t_state & (TS_CARR_ON|TS_ISOPEN)) ==
(TS_CARR_ON|TS_ISOPEN))
return (EBUSY);
#ifndef UCONSOLE
if (error = suser(p->p_ucred, &p->p_acflag))
return (error);
#endif
constty = tp;
} else if (tp == constty)
constty = NULL;
break;
case TIOCDRAIN:
if (error = ttywait(tp))
return (error);
break;
default:
#ifdef COMPAT_43
return (ttcompat(tp, com, data, flag));
#else
return (-1);
#endif
}
return (0);
}
ttnread(tp)
struct tty *tp;
{
int nread = 0;
if (tp->t_lflag & PENDIN)
ttypend(tp);
nread = RB_LEN(&tp->t_can);
if ((tp->t_lflag & ICANON) == 0)
nread += RB_LEN(&tp->t_raw);
return (nread);
}
ttselect(dev, rw, p)
dev_t dev;
int rw;
struct proc *p;
{
register struct tty *tp = &cdevsw[major(dev)].d_ttys[minor(dev)];
int nread;
int s = spltty();
switch (rw) {
case FREAD:
nread = ttnread(tp);
if (nread > 0 ||
((tp->t_cflag&CLOCAL) == 0 && (tp->t_state&TS_CARR_ON) == 0))
goto win;
if (tp->t_rsel && tp->t_rsel->p_wchan == (caddr_t)&selwait)
tp->t_state |= TS_RCOLL;
else
tp->t_rsel = p;
break;
case FWRITE:
if (RB_LEN(&tp->t_out) <= tp->t_lowat)
goto win;
if (tp->t_wsel && tp->t_wsel->p_wchan == (caddr_t)&selwait)
tp->t_state |= TS_WCOLL;
else
tp->t_wsel = p;
break;
}
splx(s);
return (0);
win:
splx(s);
return (1);
}
/*
* Initial open of tty, or (re)entry to standard tty line discipline.
*/
ttyopen(dev, tp)
dev_t dev;
register struct tty *tp;
{
tp->t_dev = dev;
tp->t_state &= ~TS_WOPEN;
if ((tp->t_state & TS_ISOPEN) == 0) {
tp->t_state |= TS_ISOPEN;
initrb(&tp->t_raw);
initrb(&tp->t_can);
initrb(&tp->t_out);
bzero((caddr_t)&tp->t_winsize, sizeof(tp->t_winsize));
}
return (0);
}
/*
* "close" a line discipline
*/
ttylclose(tp, flag)
struct tty *tp;
int flag;
{
if (flag&IO_NDELAY)
ttyflush(tp, FREAD|FWRITE);
else
ttywflush(tp);
}
/*
* Handle close() on a tty line: flush and set to initial state,
* bumping generation number so that pending read/write calls
* can detect recycling of the tty.
*/
ttyclose(tp)
register struct tty *tp;
{
if (constty == tp)
constty = NULL;
ttyflush(tp, FREAD|FWRITE);
tp->t_session = NULL;
tp->t_pgrp = NULL;
tp->t_state = 0;
tp->t_gen++;
return (0);
}
/*
* Handle modem control transition on a tty.
* Flag indicates new state of carrier.
* Returns 0 if the line should be turned off, otherwise 1.
*/
ttymodem(tp, flag)
register struct tty *tp;
{
if ((tp->t_state&TS_WOPEN) == 0 && (tp->t_lflag&MDMBUF)) {
/*
* MDMBUF: do flow control according to carrier flag
*/
if (flag) {
tp->t_state &= ~TS_TTSTOP;
ttstart(tp);
} else if ((tp->t_state&TS_TTSTOP) == 0) {
tp->t_state |= TS_TTSTOP;
(*cdevsw[major(tp->t_dev)].d_stop)(tp, 0);
}
} else if (flag == 0) {
/*
* Lost carrier.
*/
tp->t_state &= ~TS_CARR_ON;
if (tp->t_state&TS_ISOPEN && (tp->t_cflag&CLOCAL) == 0) {
if (tp->t_session && tp->t_session->s_leader)
psignal(tp->t_session->s_leader, SIGHUP);
ttyflush(tp, FREAD|FWRITE);
return (0);
}
} else {
/*
* Carrier now on.
*/
tp->t_state |= TS_CARR_ON;
ttwakeup(tp);
}
return (1);
}
/*
* Default modem control routine (for other line disciplines).
* Return argument flag, to turn off device on carrier drop.
*/
nullmodem(tp, flag)
register struct tty *tp;
int flag;
{
if (flag)
tp->t_state |= TS_CARR_ON;
else {
tp->t_state &= ~TS_CARR_ON;
if ((tp->t_cflag&CLOCAL) == 0) {
if (tp->t_session && tp->t_session->s_leader)
psignal(tp->t_session->s_leader, SIGHUP);
return (0);
}
}
return (1);
}
/*
* reinput pending characters after state switch
* call at spltty().
*/
ttypend(tp)
register struct tty *tp;
{
register c;
char *hd, *tl;
tp->t_lflag &= ~PENDIN;
tp->t_state |= TS_TYPEN;
hd = tp->t_raw.rb_hd;
tl = tp->t_raw.rb_tl;
flushq(&tp->t_raw);
while (hd != tl) {
ttyinput(*hd, tp);
hd = RB_SUCC(&tp->t_raw, hd);
}
tp->t_state &= ~TS_TYPEN;
}
/*
* Process input of a single character received on a tty.
*/
ttyinput(c, tp)
register c;
register struct tty *tp;
{
register int iflag = tp->t_iflag;
register int lflag = tp->t_lflag;
register u_char *cc = tp->t_cc;
int i, err;
/*
* If input is pending take it first.
*/
if (lflag&PENDIN)
ttypend(tp);
/*
* Gather stats.
*/
tk_nin++;
if (lflag&ICANON) {
tk_cancc++;
tp->t_cancc++;
} else {
tk_rawcc++;
tp->t_rawcc++;
}
/*
* Handle exceptional conditions (break, parity, framing).
*/
if (err = (c&TTY_ERRORMASK)) {
c &= ~TTY_ERRORMASK;
if (err&TTY_FE && !c) { /* break */
if (iflag&IGNBRK)
goto endcase;
else if (iflag&BRKINT && lflag&ISIG &&
(cc[VINTR] != _POSIX_VDISABLE))
c = cc[VINTR];
else if (iflag&PARMRK)
goto parmrk;
} else if ((err&TTY_PE && iflag&INPCK) || err&TTY_FE) {
if (iflag&IGNPAR)
goto endcase;
else if (iflag&PARMRK) {
parmrk:
putc(0377|TTY_QUOTE, &tp->t_raw);
putc(0|TTY_QUOTE, &tp->t_raw);
putc(c|TTY_QUOTE, &tp->t_raw);
goto endcase;
} else
c = 0;
}
}
/*
* In tandem mode, check high water mark.
*/
if (iflag&IXOFF)
ttyblock(tp);
if ((tp->t_state&TS_TYPEN) == 0 && (iflag&ISTRIP))
c &= ~0x80;
if ((tp->t_lflag&EXTPROC) == 0) {
/*
* Check for literal nexting very first
*/
if (tp->t_state&TS_LNCH) {
c |= TTY_QUOTE;
tp->t_state &= ~TS_LNCH;
}
/*
* Scan for special characters. This code
* is really just a big case statement with
* non-constant cases. The bottom of the
* case statement is labeled ``endcase'', so goto
* it after a case match, or similar.
*/
/*
* Control chars which aren't controlled
* by ICANON, ISIG, or IXON.
*/
if (lflag&IEXTEN) {
if (CCEQ(cc[VLNEXT], c)) {
if (lflag&ECHO) {
if (lflag&ECHOE)
ttyoutstr("^\b", tp);
else
ttyecho(c, tp);
}
tp->t_state |= TS_LNCH;
goto endcase;
}
if (CCEQ(cc[VDISCARD], c)) {
if (lflag&FLUSHO)
tp->t_lflag &= ~FLUSHO;
else {
ttyflush(tp, FWRITE);
ttyecho(c, tp);
if (RB_LEN(&tp->t_raw) + RB_LEN(&tp->t_can))
ttyretype(tp);
tp->t_lflag |= FLUSHO;
}
goto startoutput;
}
}
/*
* Signals.
*/
if (lflag&ISIG) {
if (CCEQ(cc[VINTR], c) || CCEQ(cc[VQUIT], c)) {
if ((lflag&NOFLSH) == 0)
ttyflush(tp, FREAD|FWRITE);
ttyecho(c, tp);
pgsignal(tp->t_pgrp,
CCEQ(cc[VINTR], c) ? SIGINT : SIGQUIT, 1);
goto endcase;
}
if (CCEQ(cc[VSUSP], c)) {
if ((lflag&NOFLSH) == 0)
ttyflush(tp, FREAD);
ttyecho(c, tp);
pgsignal(tp->t_pgrp, SIGTSTP, 1);
goto endcase;
}
}
/*
* Handle start/stop characters.
*/
if (iflag&IXON) {
if (CCEQ(cc[VSTOP], c)) {
if ((tp->t_state&TS_TTSTOP) == 0) {
tp->t_state |= TS_TTSTOP;
(*cdevsw[major(tp->t_dev)].d_stop)(tp,
0);
return;
}
if (!CCEQ(cc[VSTART], c))
return;
/*
* if VSTART == VSTOP then toggle
*/
goto endcase;
}
if (CCEQ(cc[VSTART], c))
goto restartoutput;
}
/*
* IGNCR, ICRNL, & INLCR
*/
if (c == '\r') {
if (iflag&IGNCR)
goto endcase;
else if (iflag&ICRNL)
c = '\n';
} else if (c == '\n' && iflag&INLCR)
c = '\r';
}
if ((tp->t_lflag&EXTPROC) == 0 && lflag&ICANON) {
/*
* From here on down canonical mode character
* processing takes place.
*/
/*
* erase (^H / ^?)
*/
if (CCEQ(cc[VERASE], c)) {
if (RB_LEN(&tp->t_raw))
ttyrub(unputc(&tp->t_raw), tp);
goto endcase;
}
/*
* kill (^U)
*/
if (CCEQ(cc[VKILL], c)) {
if (lflag&ECHOKE && RB_LEN(&tp->t_raw) == tp->t_rocount &&
(lflag&ECHOPRT) == 0) {
while (RB_LEN(&tp->t_raw))
ttyrub(unputc(&tp->t_raw), tp);
} else {
ttyecho(c, tp);
if (lflag&ECHOK || lflag&ECHOKE)
ttyecho('\n', tp);
while (getc(&tp->t_raw) > 0)
;
tp->t_rocount = 0;
}
tp->t_state &= ~TS_LOCAL;
goto endcase;
}
/*
* word erase (^W)
*/
if (CCEQ(cc[VWERASE], c)) {
int ctype;
int alt = lflag&ALTWERASE;
/*
* erase whitespace
*/
while ((c = unputc(&tp->t_raw)) == ' ' || c == '\t')
ttyrub(c, tp);
if (c == -1)
goto endcase;
/*
* erase last char of word and remember the
* next chars type (for ALTWERASE)
*/
ttyrub(c, tp);
c = unputc(&tp->t_raw);
if (c == -1)
goto endcase;
ctype = ISALPHA(c);
/*
* erase rest of word
*/
do {
ttyrub(c, tp);
c = unputc(&tp->t_raw);
if (c == -1)
goto endcase;
} while (c != ' ' && c != '\t' &&
(alt == 0 || ISALPHA(c) == ctype));
(void) putc(c, &tp->t_raw);
goto endcase;
}
/*
* reprint line (^R)
*/
if (CCEQ(cc[VREPRINT], c)) {
ttyretype(tp);
goto endcase;
}
/*
* ^T - kernel info and generate SIGINFO
*/
if (CCEQ(cc[VSTATUS], c)) {
pgsignal(tp->t_pgrp, SIGINFO, 1);
if ((lflag&NOKERNINFO) == 0)
ttyinfo(tp);
goto endcase;
}
}
/*
* Check for input buffer overflow
*/
if (RB_LEN(&tp->t_raw)+RB_LEN(&tp->t_can) >= TTYHOG) {
if (iflag&IMAXBEL) {
if (RB_LEN(&tp->t_out) < tp->t_hiwat)
(void) ttyoutput(CTRL('g'), tp);
} else
ttyflush(tp, FREAD | FWRITE);
goto endcase;
}
/*
* Put data char in q for user and
* wakeup on seeing a line delimiter.
*/
if (putc(c, &tp->t_raw) >= 0) {
if ((lflag&ICANON) == 0) {
ttwakeup(tp);
ttyecho(c, tp);
goto endcase;
}
if (ttbreakc(c)) {
tp->t_rocount = 0;
catb(&tp->t_raw, &tp->t_can);
ttwakeup(tp);
} else if (tp->t_rocount++ == 0)
tp->t_rocol = tp->t_col;
if (tp->t_state&TS_ERASE) {
/*
* end of prterase \.../
*/
tp->t_state &= ~TS_ERASE;
(void) ttyoutput('/', tp);
}
i = tp->t_col;
ttyecho(c, tp);
if (CCEQ(cc[VEOF], c) && lflag&ECHO) {
/*
* Place the cursor over the '^' of the ^D.
*/
i = MIN(2, tp->t_col - i);
while (i > 0) {
(void) ttyoutput('\b', tp);
i--;
}
}
}
endcase:
/*
* IXANY means allow any character to restart output.
*/
if ((tp->t_state&TS_TTSTOP) && (iflag&IXANY) == 0 &&
cc[VSTART] != cc[VSTOP])
return;
restartoutput:
tp->t_state &= ~TS_TTSTOP;
tp->t_lflag &= ~FLUSHO;
startoutput:
ttstart(tp);
}
/*
* Output a single character on a tty, doing output processing
* as needed (expanding tabs, newline processing, etc.).
* Returns < 0 if putc succeeds, otherwise returns char to resend.
* Must be recursive.
*/
ttyoutput(c, tp)
register c;
register struct tty *tp;
{
register int col;
register long oflag = tp->t_oflag;
if ((oflag&OPOST) == 0) {
if (tp->t_lflag&FLUSHO)
return (-1);
if (putc(c, &tp->t_out))
return (c);
tk_nout++;
tp->t_outcc++;
return (-1);
}
c &= TTY_CHARMASK;
/*
* Do tab expansion if OXTABS is set.
* Special case if we have external processing, we don't
* do the tab expansion because we'll probably get it
* wrong. If tab expansion needs to be done, let it
* happen externally.
*/
if (c == '\t' && oflag&OXTABS && (tp->t_lflag&EXTPROC) == 0) {
register int s;
c = 8 - (tp->t_col&7);
if ((tp->t_lflag&FLUSHO) == 0) {
int i;
s = spltty(); /* don't interrupt tabs */
#ifdef was
c -= b_to_q(" ", c, &tp->t_outq);
#else
i = min (c, RB_CONTIGPUT(&tp->t_out));
bcopy(" ", tp->t_out.rb_tl, i);
tp->t_out.rb_tl =
RB_ROLLOVER(&tp->t_out, tp->t_out.rb_tl+i);
i = min (c-i, RB_CONTIGPUT(&tp->t_out));
/* off end and still have space? */
if (i) {
bcopy(" ", tp->t_out.rb_tl, i);
tp->t_out.rb_tl =
RB_ROLLOVER(&tp->t_out, tp->t_out.rb_tl+i);
}
#endif
tk_nout += c;
tp->t_outcc += c;
splx(s);
}
tp->t_col += c;
return (c ? -1 : '\t');
}
if (c == CEOT && oflag&ONOEOT)
return (-1);
tk_nout++;
tp->t_outcc++;
/*
* Newline translation: if ONLCR is set,
* translate newline into "\r\n".
*/
if (c == '\n' && (tp->t_oflag&ONLCR) && ttyoutput('\r', tp) >= 0)
return (c);
if ((tp->t_lflag&FLUSHO) == 0 && putc(c, &tp->t_out))
return (c);
col = tp->t_col;
switch (CCLASS(c)) {
case ORDINARY:
col++;
case CONTROL:
break;
case BACKSPACE:
if (col > 0)
col--;
break;
case NEWLINE:
col = 0;
break;
case TAB:
col = (col + 8) &~ 0x7;
break;
case RETURN:
col = 0;
}
tp->t_col = col;
return (-1);
}
/*
* Process a read call on a tty device.
*/
ttread(tp, uio, flag)
register struct tty *tp;
struct uio *uio;
{
register struct ringb *qp;
register int c;
register long lflag;
register u_char *cc = tp->t_cc;
register struct proc *p = curproc;
int s, first, error = 0;
loop:
lflag = tp->t_lflag;
s = spltty();
/*
* take pending input first
*/
if (lflag&PENDIN)
ttypend(tp);
splx(s);
/*
* Hang process if it's in the background.
*/
if (isbackground(p, tp)) {
if ((p->p_sigignore & sigmask(SIGTTIN)) ||
(p->p_sigmask & sigmask(SIGTTIN)) ||
p->p_flag&SPPWAIT || p->p_pgrp->pg_jobc == 0)
return (EIO);
pgsignal(p->p_pgrp, SIGTTIN, 1);
if (error = ttysleep(tp, (caddr_t)&lbolt, TTIPRI | PCATCH,
ttybg, 0))
return (error);
goto loop;
}
/*
* If canonical, use the canonical queue,
* else use the raw queue.
*/
qp = lflag&ICANON ? &tp->t_can : &tp->t_raw;
/*
* If there is no input, sleep on rawq
* awaiting hardware receipt and notification.
* If we have data, we don't need to check for carrier.
*/
s = spltty();
if (RB_LEN(qp) <= 0) {
int carrier;
carrier = (tp->t_state&TS_CARR_ON) || (tp->t_cflag&CLOCAL);
if (!carrier && tp->t_state&TS_ISOPEN) {
splx(s);
return (0); /* EOF */
}
if (flag & IO_NDELAY) {
splx(s);
return (EWOULDBLOCK);
}
error = ttysleep(tp, (caddr_t)&tp->t_raw, TTIPRI | PCATCH,
carrier ? ttyin : ttopen, 0);
splx(s);
if (error)
return (error);
goto loop;
}
splx(s);
/*
* Input present, check for input mapping and processing.
*/
first = 1;
while ((c = getc(qp)) >= 0) {
/*
* delayed suspend (^Y)
*/
if (CCEQ(cc[VDSUSP], c) && lflag&ISIG) {
pgsignal(tp->t_pgrp, SIGTSTP, 1);
if (first) {
if (error = ttysleep(tp, (caddr_t)&lbolt,
TTIPRI | PCATCH, ttybg, 0))
break;
goto loop;
}
break;
}
/*
* Interpret EOF only in canonical mode.
*/
if (CCEQ(cc[VEOF], c) && lflag&ICANON)
break;
/*
* Give user character.
*/
error = ureadc(c, uio);
if (error)
break;
if (uio->uio_resid == 0)
break;
/*
* In canonical mode check for a "break character"
* marking the end of a "line of input".
*/
if (lflag&ICANON && ttbreakc(c))
break;
first = 0;
}
/*
* Look to unblock output now that (presumably)
* the input queue has gone down.
*/
if (tp->t_state&TS_TBLOCK && RB_LEN(&tp->t_raw) < TTYHOG/5) {
if (cc[VSTART] != _POSIX_VDISABLE &&
putc(cc[VSTART], &tp->t_out) == 0) {
tp->t_state &= ~TS_TBLOCK;
ttstart(tp);
}
}
return (error);
}
/*
* Check the output queue on tp for space for a kernel message
* (from uprintf/tprintf). Allow some space over the normal
* hiwater mark so we don't lose messages due to normal flow
* control, but don't let the tty run amok.
* Sleeps here are not interruptible, but we return prematurely
* if new signals come in.
*/
ttycheckoutq(tp, wait)
register struct tty *tp;
int wait;
{
int hiwat, s, oldsig;
extern int wakeup();
hiwat = tp->t_hiwat;
s = spltty();
if (curproc)
oldsig = curproc->p_sig;
else
oldsig = 0;
if (RB_LEN(&tp->t_out) > hiwat + 200)
while (RB_LEN(&tp->t_out) > hiwat) {
ttstart(tp);
if (wait == 0 || (curproc && curproc->p_sig != oldsig)) {
splx(s);
return (0);
}
timeout(wakeup, (caddr_t)&tp->t_out, hz);
tp->t_state |= TS_ASLEEP;
sleep((caddr_t)&tp->t_out, PZERO - 1);
}
splx(s);
return (1);
}
/*
* Process a write call on a tty device.
*/
ttwrite(tp, uio, flag)
register struct tty *tp;
register struct uio *uio;
{
register char *cp;
register int cc = 0, ce;
register struct proc *p = curproc;
int i, hiwat, cnt, error, s;
char obuf[OBUFSIZ];
hiwat = tp->t_hiwat;
cnt = uio->uio_resid;
error = 0;
loop:
s = spltty();
if ((tp->t_state&TS_CARR_ON) == 0 && (tp->t_cflag&CLOCAL) == 0) {
if (tp->t_state&TS_ISOPEN) {
splx(s);
return (EIO);
} else if (flag & IO_NDELAY) {
splx(s);
error = EWOULDBLOCK;
goto out;
} else {
/*
* sleep awaiting carrier
*/
error = ttysleep(tp, (caddr_t)&tp->t_raw,
TTIPRI | PCATCH,ttopen, 0);
splx(s);
if (error)
goto out;
goto loop;
}
}
splx(s);
/*
* Hang the process if it's in the background.
*/
if (isbackground(p, tp) &&
tp->t_lflag&TOSTOP && (p->p_flag&SPPWAIT) == 0 &&
(p->p_sigignore & sigmask(SIGTTOU)) == 0 &&
(p->p_sigmask & sigmask(SIGTTOU)) == 0 &&
p->p_pgrp->pg_jobc) {
pgsignal(p->p_pgrp, SIGTTOU, 1);
if (error = ttysleep(tp, (caddr_t)&lbolt, TTIPRI | PCATCH,
ttybg, 0))
goto out;
goto loop;
}
/*
* Process the user's data in at most OBUFSIZ
* chunks. Perform any output translation.
* Keep track of high water mark, sleep on overflow
* awaiting device aid in acquiring new space.
*/
while (uio->uio_resid > 0 || cc > 0) {
if (tp->t_lflag&FLUSHO) {
uio->uio_resid = 0;
return (0);
}
if (RB_LEN(&tp->t_out) > hiwat)
goto ovhiwat;
/*
* Grab a hunk of data from the user,
* unless we have some leftover from last time.
*/
if (cc == 0) {
cc = min(uio->uio_resid, OBUFSIZ);
cp = obuf;
error = uiomove(cp, cc, uio);
if (error) {
cc = 0;
break;
}
}
/*
* If nothing fancy need be done, grab those characters we
* can handle without any of ttyoutput's processing and
* just transfer them to the output q. For those chars
* which require special processing (as indicated by the
* bits in partab), call ttyoutput. After processing
* a hunk of data, look for FLUSHO so ^O's will take effect
* immediately.
*/
while (cc > 0) {
if ((tp->t_oflag&OPOST) == 0)
ce = cc;
else {
ce = cc - scanc((unsigned)cc, (u_char *)cp,
(u_char *)partab, CCLASSMASK);
/*
* If ce is zero, then we're processing
* a special character through ttyoutput.
*/
if (ce == 0) {
tp->t_rocount = 0;
if (ttyoutput(*cp, tp) >= 0) {
/* no c-lists, wait a bit */
ttstart(tp);
if (error = ttysleep(tp,
(caddr_t)&lbolt,
TTOPRI | PCATCH, ttybuf, 0))
break;
goto loop;
}
cp++, cc--;
if ((tp->t_lflag&FLUSHO) ||
RB_LEN(&tp->t_out) > hiwat)
goto ovhiwat;
continue;
}
}
/*
* A bunch of normal characters have been found,
* transfer them en masse to the output queue and
* continue processing at the top of the loop.
* If there are any further characters in this
* <= OBUFSIZ chunk, the first should be a character
* requiring special handling by ttyoutput.
*/
tp->t_rocount = 0;
#ifdef was
i = b_to_q(cp, ce, &tp->t_outq);
ce -= i;
#else
i = ce;
ce = min (ce, RB_CONTIGPUT(&tp->t_out));
bcopy(cp, tp->t_out.rb_tl, ce);
tp->t_out.rb_tl = RB_ROLLOVER(&tp->t_out,
tp->t_out.rb_tl + ce);
i -= ce;
if (i > 0) {
int ii;
ii = min (i, RB_CONTIGPUT(&tp->t_out));
bcopy(cp + ce, tp->t_out.rb_tl, ii);
tp->t_out.rb_tl = RB_ROLLOVER(&tp->t_out,
tp->t_out.rb_tl + ii);
i -= ii;
ce += ii;
}
#endif
tp->t_col += ce;
cp += ce, cc -= ce, tk_nout += ce;
tp->t_outcc += ce;
if (i > 0) {
/* out of space, wait a bit */
ttstart(tp);
if (error = ttysleep(tp, (caddr_t)&lbolt,
TTOPRI | PCATCH, ttybuf, 0))
break;
goto loop;
}
if (tp->t_lflag&FLUSHO || RB_LEN(&tp->t_out) > hiwat)
break;
}
ttstart(tp);
}
out:
/*
* If cc is nonzero, we leave the uio structure inconsistent,
* as the offset and iov pointers have moved forward,
* but it doesn't matter (the call will either return short
* or restart with a new uio).
*/
uio->uio_resid += cc;
return (error);
ovhiwat:
ttstart(tp);
s = spltty();
/*
* This can only occur if FLUSHO is set in t_lflag,
* or if ttstart/oproc is synchronous (or very fast).
*/
if (RB_LEN(&tp->t_out) <= hiwat) {
splx(s);
goto loop;
}
if (flag & IO_NDELAY) {
splx(s);
uio->uio_resid += cc;
if (uio->uio_resid == cnt)
return (EWOULDBLOCK);
return (0);
}
tp->t_state |= TS_ASLEEP;
error = ttysleep(tp, (caddr_t)&tp->t_out, TTOPRI | PCATCH, ttyout, 0);
splx(s);
if (error)
goto out;
goto loop;
}
/*
* Rubout one character from the rawq of tp
* as cleanly as possible.
*/
ttyrub(c, tp)
register c;
register struct tty *tp;
{
char *cp;
register int savecol;
int s;
if ((tp->t_lflag&ECHO) == 0 || (tp->t_lflag&EXTPROC))
return;
tp->t_lflag &= ~FLUSHO;
if (tp->t_lflag&ECHOE) {
if (tp->t_rocount == 0) {
/*
* Screwed by ttwrite; retype
*/
ttyretype(tp);
return;
}
if (c == ('\t'|TTY_QUOTE) || c == ('\n'|TTY_QUOTE))
ttyrubo(tp, 2);
else switch (CCLASS(c &= TTY_CHARMASK)) {
case ORDINARY:
ttyrubo(tp, 1);
break;
case VTAB:
case BACKSPACE:
case CONTROL:
case RETURN:
case NEWLINE:
if (tp->t_lflag&ECHOCTL)
ttyrubo(tp, 2);
break;
case TAB: {
int c;
if (tp->t_rocount < RB_LEN(&tp->t_raw)) {
ttyretype(tp);
return;
}
s = spltty();
savecol = tp->t_col;
tp->t_state |= TS_CNTTB;
tp->t_lflag |= FLUSHO;
tp->t_col = tp->t_rocol;
cp = tp->t_raw.rb_hd;
for (c = nextc(&cp, &tp->t_raw); c ;
c = nextc(&cp, &tp->t_raw))
ttyecho(c, tp);
tp->t_lflag &= ~FLUSHO;
tp->t_state &= ~TS_CNTTB;
splx(s);
/*
* savecol will now be length of the tab
*/
savecol -= tp->t_col;
tp->t_col += savecol;
if (savecol > 8)
savecol = 8; /* overflow screw */
while (--savecol >= 0)
(void) ttyoutput('\b', tp);
break;
}
default:
/* XXX */
printf("ttyrub: would panic c = %d, val = %d\n",
c, CCLASS(c));
/*panic("ttyrub");*/
}
} else if (tp->t_lflag&ECHOPRT) {
if ((tp->t_state&TS_ERASE) == 0) {
(void) ttyoutput('\\', tp);
tp->t_state |= TS_ERASE;
}
ttyecho(c, tp);
} else
ttyecho(tp->t_cc[VERASE], tp);
tp->t_rocount--;
}
/*
* Crt back over cnt chars perhaps
* erasing them.
*/
ttyrubo(tp, cnt)
register struct tty *tp;
int cnt;
{
while (--cnt >= 0)
ttyoutstr("\b \b", tp);
}
/*
* Reprint the rawq line.
* We assume c_cc has already been checked.
*/
ttyretype(tp)
register struct tty *tp;
{
char *cp;
int s, c;
if (tp->t_cc[VREPRINT] != _POSIX_VDISABLE)
ttyecho(tp->t_cc[VREPRINT], tp);
(void) ttyoutput('\n', tp);
s = spltty();
cp = tp->t_can.rb_hd;
for (c = nextc(&cp, &tp->t_can); c ; c = nextc(&cp, &tp->t_can))
ttyecho(c, tp);
cp = tp->t_raw.rb_hd;
for (c = nextc(&cp, &tp->t_raw); c ; c = nextc(&cp, &tp->t_raw))
ttyecho(c, tp);
tp->t_state &= ~TS_ERASE;
splx(s);
tp->t_rocount = RB_LEN(&tp->t_raw);
tp->t_rocol = 0;
}
/*
* Echo a typed character to the terminal.
*/
ttyecho(c, tp)
register c;
register struct tty *tp;
{
if ((tp->t_state&TS_CNTTB) == 0)
tp->t_lflag &= ~FLUSHO;
if (((tp->t_lflag&ECHO) == 0 &&
((tp->t_lflag&ECHONL) == 0 || c == '\n')) || (tp->t_lflag&EXTPROC))
return;
if (tp->t_lflag&ECHOCTL) {
if ((c&TTY_CHARMASK) <= 037 && c != '\t' && c != '\n' ||
c == 0177) {
(void) ttyoutput('^', tp);
c &= TTY_CHARMASK;
if (c == 0177)
c = '?';
else
c += 'A' - 1;
}
}
(void) ttyoutput(c, tp);
}
/*
* send string cp to tp
*/
ttyoutstr(cp, tp)
register char *cp;
register struct tty *tp;
{
register char c;
while (c = *cp++)
(void) ttyoutput(c, tp);
}
/*
* Wake up any readers on a tty.
*/
ttwakeup(tp)
register struct tty *tp;
{
if (tp->t_rsel) {
selwakeup(tp->t_rsel, tp->t_state&TS_RCOLL);
tp->t_state &= ~TS_RCOLL;
tp->t_rsel = 0;
}
if (tp->t_state & TS_ASYNC)
pgsignal(tp->t_pgrp, SIGIO, 1);
wakeup((caddr_t)&tp->t_raw);
}
/*
* Look up a code for a specified speed in a conversion table;
* used by drivers to map software speed values to hardware parameters.
*/
ttspeedtab(speed, table)
register struct speedtab *table;
{
for ( ; table->sp_speed != -1; table++)
if (table->sp_speed == speed)
return (table->sp_code);
return (-1);
}
/*
* set tty hi and low water marks
*
* Try to arrange the dynamics so there's about one second
* from hi to low water.
*
*/
ttsetwater(tp)
struct tty *tp;
{
register cps = tp->t_ospeed / 10;
register x;
#define clamp(x, h, l) ((x)>h ? h : ((x)<l) ? l : (x))
tp->t_lowat = x = clamp(cps/2, TTMAXLOWAT, TTMINLOWAT);
x += cps;
x = clamp(x, TTMAXHIWAT, TTMINHIWAT);
tp->t_hiwat = roundup(x, CBSIZE);
#undef clamp
}
/*
* Report on state of foreground process group.
*/
ttyinfo(tp)
register struct tty *tp;
{
register struct proc *p, *pick;
struct timeval utime, stime;
int tmp;
if (ttycheckoutq(tp,0) == 0)
return;
/* Print load average. */
tmp = (averunnable[0] * 100 + FSCALE / 2) >> FSHIFT;
ttyprintf(tp, "load: %d.%02d ", tmp / 100, tmp % 100);
if (tp->t_session == NULL)
ttyprintf(tp, "not a controlling terminal\n");
else if (tp->t_pgrp == NULL)
ttyprintf(tp, "no foreground process group\n");
else if ((p = tp->t_pgrp->pg_mem) == NULL)
ttyprintf(tp, "empty foreground process group\n");
else {
/* Pick interesting process. */
for (pick = NULL; p != NULL; p = p->p_pgrpnxt)
if (proc_compare(pick, p))
pick = p;
ttyprintf(tp, " cmd: %s %d [%s] ", pick->p_comm, pick->p_pid,
pick->p_stat == SRUN ? "running" :
pick->p_wmesg ? pick->p_wmesg : "iowait");
/*
* Lock out clock if process is running; get user/system
* cpu time.
*/
if (curproc == pick)
tmp = splclock();
utime = pick->p_utime;
stime = pick->p_stime;
if (curproc == pick)
splx(tmp);
/* Print user time. */
ttyprintf(tp, "%d.%02du ",
utime.tv_sec, (utime.tv_usec + 5000) / 10000);
/* Print system time. */
ttyprintf(tp, "%d.%02ds ",
stime.tv_sec, (stime.tv_usec + 5000) / 10000);
#define pgtok(a) (((a) * NBPG) / 1024)
/* Print percentage cpu, resident set size. */
tmp = pick->p_pctcpu * 10000 + FSCALE / 2 >> FSHIFT;
ttyprintf(tp, "%d%% %dk\n",
tmp / 100, pgtok(pick->p_vmspace->vm_rssize));
}
tp->t_rocount = 0; /* so pending input will be retyped if BS */
}
/*
* Returns 1 if p2 is "better" than p1
*
* The algorithm for picking the "interesting" process is thus:
*
* 1) (Only foreground processes are eligable - implied)
* 2) Runnable processes are favored over anything
* else. The runner with the highest cpu
* utilization is picked (p_cpu). Ties are
* broken by picking the highest pid.
* 3 Next, the sleeper with the shortest sleep
* time is favored. With ties, we pick out
* just "short-term" sleepers (SSINTR == 0).
* Further ties are broken by picking the highest
* pid.
*
*/
#define isrun(p) (((p)->p_stat == SRUN) || ((p)->p_stat == SIDL))
#define TESTAB(a, b) ((a)<<1 | (b))
#define ONLYA 2
#define ONLYB 1
#define BOTH 3
static int
proc_compare(p1, p2)
register struct proc *p1, *p2;
{
if (p1 == NULL)
return (1);
/*
* see if at least one of them is runnable
*/
switch (TESTAB(isrun(p1), isrun(p2))) {
case ONLYA:
return (0);
case ONLYB:
return (1);
case BOTH:
/*
* tie - favor one with highest recent cpu utilization
*/
if (p2->p_cpu > p1->p_cpu)
return (1);
if (p1->p_cpu > p2->p_cpu)
return (0);
return (p2->p_pid > p1->p_pid); /* tie - return highest pid */
}
/*
* weed out zombies
*/
switch (TESTAB(p1->p_stat == SZOMB, p2->p_stat == SZOMB)) {
case ONLYA:
return (1);
case ONLYB:
return (0);
case BOTH:
return (p2->p_pid > p1->p_pid); /* tie - return highest pid */
}
/*
* pick the one with the smallest sleep time
*/
if (p2->p_slptime > p1->p_slptime)
return (0);
if (p1->p_slptime > p2->p_slptime)
return (1);
/*
* favor one sleeping in a non-interruptible sleep
*/
if (p1->p_flag&SSINTR && (p2->p_flag&SSINTR) == 0)
return (1);
if (p2->p_flag&SSINTR && (p1->p_flag&SSINTR) == 0)
return (0);
return (p2->p_pid > p1->p_pid); /* tie - return highest pid */
}
/*
* Output char to tty; console putchar style.
*/
tputchar(c, tp)
int c;
struct tty *tp;
{
register s = spltty();
if ((tp->t_state & (TS_CARR_ON|TS_ISOPEN)) == (TS_CARR_ON|TS_ISOPEN)) {
if (c == '\n')
(void) ttyoutput('\r', tp);
(void) ttyoutput(c, tp);
ttstart(tp);
splx(s);
return (0);
}
splx(s);
return (-1);
}
/*
* Sleep on chan, returning ERESTART if tty changed
* while we napped and returning any errors (e.g. EINTR/ETIMEDOUT)
* reported by tsleep. If the tty is revoked, restarting a pending
* call will redo validation done at the start of the call.
*/
ttysleep(tp, chan, pri, wmesg, timo)
struct tty *tp;
caddr_t chan;
int pri;
char *wmesg;
int timo;
{
int error;
short gen = tp->t_gen;
if (error = tsleep(chan, pri, wmesg, timo))
return (error);
if (tp->t_gen != gen)
return (ERESTART);
return (0);
}