2 * Copyright (c) 1982, 1986, 1990, 1991, 1993
3 * The Regents of the University of California. All rights reserved.
4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
6 * to the University of California by American Telephone and Telegraph
7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8 * the permission of UNIX System Laboratories, Inc.
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11 * modification, are permitted provided that the following conditions
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14 * notice, this list of conditions and the following disclaimer.
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19 * must display the following acknowledgement:
20 * This product includes software developed by the University of
21 * California, Berkeley and its contributors.
22 * 4. Neither the name of the University nor the names of its contributors
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34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
38 * @(#)tty.c 8.8 (Berkeley) 1/21/94
39 * $FreeBSD: src/sys/kern/tty.c,v 1.129.2.5 2002/03/11 01:32:31 dd Exp $
40 * $DragonFly: src/sys/kern/tty.c,v 1.31 2006/09/19 11:47:35 corecode Exp $
45 * o Fix races for sending the start char in ttyflush().
46 * o Handle inter-byte timeout for "MIN > 0, TIME > 0" in ttyselect().
47 * With luck, there will be MIN chars before select() returns().
48 * o Handle CLOCAL consistently for ptys. Perhaps disallow setting it.
49 * o Don't allow input in TS_ZOMBIE case. It would be visible through
51 * o Do the new sio locking stuff here and use it to avoid special
54 * o Move EXTPROC and/or PENDIN to t_state?
55 * o Wrap most of ttioctl in spltty/splx.
56 * o Implement TIOCNOTTY or remove it from <sys/ioctl.h>.
57 * o Send STOP if IXOFF is toggled off while TS_TBLOCK is set.
58 * o Don't allow certain termios flags to affect disciplines other
59 * than TTYDISC. Cancel their effects before switch disciplines
60 * and ignore them if they are set while we are in another
62 * o Now that historical speed conversions are handled here, don't
64 * o Check for TS_CARR_ON being set while everything is closed and not
65 * waiting for carrier. TS_CARR_ON isn't cleared if nothing is open,
66 * so it would live until the next open even if carrier drops.
67 * o Restore TS_WOPEN since it is useful in pstat. It must be cleared
68 * only when _all_ openers leave open().
71 #include "opt_compat.h"
72 #include "opt_uconsole.h"
74 #include <sys/param.h>
75 #include <sys/systm.h>
76 #include <sys/filio.h>
77 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
78 #include <sys/ioctl_compat.h>
83 #include <sys/clist.h>
85 #include <sys/fcntl.h>
87 #include <sys/dkstat.h>
89 #include <sys/kernel.h>
90 #include <sys/vnode.h>
91 #include <sys/signalvar.h>
92 #include <sys/resourcevar.h>
93 #include <sys/malloc.h>
94 #include <sys/filedesc.h>
95 #include <sys/sysctl.h>
96 #include <sys/thread2.h>
101 #include <vm/vm_map.h>
103 MALLOC_DEFINE(M_TTYS, "ttys", "tty data structures");
105 static int proc_compare (struct proc *p1, struct proc *p2);
106 static int ttnread (struct tty *tp);
107 static void ttyecho (int c, struct tty *tp);
108 static int ttyoutput (int c, struct tty *tp);
109 static void ttypend (struct tty *tp);
110 static void ttyretype (struct tty *tp);
111 static void ttyrub (int c, struct tty *tp);
112 static void ttyrubo (struct tty *tp, int cnt);
113 static void ttyunblock (struct tty *tp);
114 static int ttywflush (struct tty *tp);
115 static int filt_ttyread (struct knote *kn, long hint);
116 static void filt_ttyrdetach (struct knote *kn);
117 static int filt_ttywrite (struct knote *kn, long hint);
118 static void filt_ttywdetach (struct knote *kn);
121 * Table with character classes and parity. The 8th bit indicates parity,
122 * the 7th bit indicates the character is an alphameric or underscore (for
123 * ALTWERASE), and the low 6 bits indicate delay type. If the low 6 bits
124 * are 0 then the character needs no special processing on output; classes
125 * other than 0 might be translated or (not currently) require delays.
127 #define E 0x00 /* Even parity. */
128 #define O 0x80 /* Odd parity. */
129 #define PARITY(c) (char_type[c] & O)
131 #define ALPHA 0x40 /* Alpha or underscore. */
132 #define ISALPHA(c) (char_type[(c) & TTY_CHARMASK] & ALPHA)
134 #define CCLASSMASK 0x3f
135 #define CCLASS(c) (char_type[c] & CCLASSMASK)
140 #define NA ORDINARY | ALPHA
146 static u_char const char_type[] = {
147 E|CC, O|CC, O|CC, E|CC, O|CC, E|CC, E|CC, O|CC, /* nul - bel */
148 O|BS, E|TB, E|NL, O|CC, E|VT, O|CR, O|CC, E|CC, /* bs - si */
149 O|CC, E|CC, E|CC, O|CC, E|CC, O|CC, O|CC, E|CC, /* dle - etb */
150 E|CC, O|CC, O|CC, E|CC, O|CC, E|CC, E|CC, O|CC, /* can - us */
151 O|NO, E|NO, E|NO, O|NO, E|NO, O|NO, O|NO, E|NO, /* sp - ' */
152 E|NO, O|NO, O|NO, E|NO, O|NO, E|NO, E|NO, O|NO, /* ( - / */
153 E|NA, O|NA, O|NA, E|NA, O|NA, E|NA, E|NA, O|NA, /* 0 - 7 */
154 O|NA, E|NA, E|NO, O|NO, E|NO, O|NO, O|NO, E|NO, /* 8 - ? */
155 O|NO, E|NA, E|NA, O|NA, E|NA, O|NA, O|NA, E|NA, /* @ - G */
156 E|NA, O|NA, O|NA, E|NA, O|NA, E|NA, E|NA, O|NA, /* H - O */
157 E|NA, O|NA, O|NA, E|NA, O|NA, E|NA, E|NA, O|NA, /* P - W */
158 O|NA, E|NA, E|NA, O|NO, E|NO, O|NO, O|NO, O|NA, /* X - _ */
159 E|NO, O|NA, O|NA, E|NA, O|NA, E|NA, E|NA, O|NA, /* ` - g */
160 O|NA, E|NA, E|NA, O|NA, E|NA, O|NA, O|NA, E|NA, /* h - o */
161 O|NA, E|NA, E|NA, O|NA, E|NA, O|NA, O|NA, E|NA, /* p - w */
162 E|NA, O|NA, O|NA, E|NO, O|NO, E|NO, E|NO, O|CC, /* x - del */
164 * Meta chars; should be settable per character set;
165 * for now, treat them all as normal characters.
167 NA, NA, NA, NA, NA, NA, NA, NA,
168 NA, NA, NA, NA, NA, NA, NA, NA,
169 NA, NA, NA, NA, NA, NA, NA, NA,
170 NA, NA, NA, NA, NA, NA, NA, NA,
171 NA, NA, NA, NA, NA, NA, NA, NA,
172 NA, NA, NA, NA, NA, NA, NA, NA,
173 NA, NA, NA, NA, NA, NA, NA, NA,
174 NA, NA, NA, NA, NA, NA, NA, NA,
175 NA, NA, NA, NA, NA, NA, NA, NA,
176 NA, NA, NA, NA, NA, NA, NA, NA,
177 NA, NA, NA, NA, NA, NA, NA, NA,
178 NA, NA, NA, NA, NA, NA, NA, NA,
179 NA, NA, NA, NA, NA, NA, NA, NA,
180 NA, NA, NA, NA, NA, NA, NA, NA,
181 NA, NA, NA, NA, NA, NA, NA, NA,
182 NA, NA, NA, NA, NA, NA, NA, NA,
193 /* Macros to clear/set/test flags. */
194 #define SET(t, f) (t) |= (f)
195 #define CLR(t, f) (t) &= ~(f)
196 #define ISSET(t, f) ((t) & (f))
198 #undef MAX_INPUT /* XXX wrong in <sys/syslimits.h> */
199 #define MAX_INPUT TTYHOG /* XXX limit is usually larger for !ICANON */
202 SYSCTL_OPAQUE(_kern, OID_AUTO, tk_nin, CTLFLAG_RD, &tk_nin, sizeof(tk_nin),
203 "LU", "TTY input statistic");
205 SYSCTL_OPAQUE(_kern, OID_AUTO, tk_nout, CTLFLAG_RD, &tk_nout, sizeof(tk_nout),
206 "LU", "TTY output statistic");
210 * list of struct tty where pstat(8) can pick it up with sysctl
212 static SLIST_HEAD(, tty) tty_list;
215 * Initial open of tty, or (re)entry to standard tty line discipline.
224 if (!ISSET(tp->t_state, TS_ISOPEN)) {
225 SET(tp->t_state, TS_ISOPEN);
226 if (ISSET(tp->t_cflag, CLOCAL))
227 SET(tp->t_state, TS_CONNECTED);
228 bzero(&tp->t_winsize, sizeof(tp->t_winsize));
236 * Handle close() on a tty line: flush and set to initial state,
237 * bumping generation number so that pending read/write calls
238 * can detect recycling of the tty.
240 * XXX our caller should have done `spltty(); l_close(); ttyclose();'
241 * and l_close() should have flushed, but we repeat the spltty() and
242 * the flush in case there are buggy callers.
248 funsetown(tp->t_sigio);
253 ttyflush(tp, FREAD | FWRITE);
254 clist_free_cblocks(&tp->t_canq);
255 clist_free_cblocks(&tp->t_outq);
256 clist_free_cblocks(&tp->t_rawq);
259 tp->t_line = TTYDISC;
267 * Disassociate the tty from its session. Traditionally this has only been
268 * a half-close, meaning that the session was still allowed to point at the
269 * tty (resulting in the tty in the ps command showing something like 'p0-'),
270 * even though the tty is no longer pointing at the session.
272 * The half close seems to be useful only for 'ps' output but there is as
273 * yet no reason to remove the feature. The full-close code is currently
274 * #if 0'd out. See also sess_rele() in kern/kern_proc.c.
277 ttyclearsession(struct tty *tp)
282 if ((sp = tp->t_session) != NULL) {
283 tp->t_session = NULL;
284 #ifdef TTY_DO_FULL_CLOSE
285 /* FULL CLOSE (not yet) */
286 if (sp->s_ttyp == tp) {
289 printf("ttyclearsession: warning: sp->s_ttyp != tp "
290 "%p/%p\n", sp->s_ttyp, tp);
297 * Terminate the tty vnode association for a session. This is the
298 * 'other half' of the close. Because multiple opens of /dev/tty
299 * only generate a single open to the actual tty, the file modes
300 * are locked to FREAD|FWRITE.
303 ttyclosesession(struct session *sp, int dorele)
307 if ((vp = sp->s_ttyvp) == NULL)
310 if (vp->v_flag & VCTTYISOPEN) {
311 if (vn_lock(vp, LK_EXCLUSIVE|LK_RETRY) == 0) {
312 vclrflags(vp, VCTTYISOPEN);
313 VOP_CLOSE(vp, FREAD|FWRITE);
322 #define FLUSHQ(q) { \
324 ndflush(q, (q)->c_cc); \
327 /* Is 'c' a line delimiter ("break" character)? */
328 #define TTBREAKC(c, lflag) \
329 ((c) == '\n' || (((c) == cc[VEOF] || \
330 (c) == cc[VEOL] || ((c) == cc[VEOL2] && lflag & IEXTEN)) && \
331 (c) != _POSIX_VDISABLE))
334 * Process input of a single character received on a tty.
341 tcflag_t iflag, lflag;
346 * If input is pending take it first.
349 if (ISSET(lflag, PENDIN))
354 if (ISSET(lflag, ICANON))
361 * Block further input iff:
362 * current input > threshold AND input is available to user program
363 * AND input flow control is enabled and not yet invoked.
364 * The 3 is slop for PARMRK.
367 if (tp->t_rawq.c_cc + tp->t_canq.c_cc > tp->t_ihiwat - 3 &&
368 (!ISSET(lflag, ICANON) || tp->t_canq.c_cc != 0) &&
369 (ISSET(tp->t_cflag, CRTS_IFLOW) || ISSET(iflag, IXOFF)) &&
370 !ISSET(tp->t_state, TS_TBLOCK))
373 /* Handle exceptional conditions (break, parity, framing). */
375 err = (ISSET(c, TTY_ERRORMASK));
377 CLR(c, TTY_ERRORMASK);
378 if (ISSET(err, TTY_BI)) {
379 if (ISSET(iflag, IGNBRK))
381 if (ISSET(iflag, BRKINT)) {
382 ttyflush(tp, FREAD | FWRITE);
383 pgsignal(tp->t_pgrp, SIGINT, 1);
386 if (ISSET(iflag, PARMRK))
388 } else if ((ISSET(err, TTY_PE) && ISSET(iflag, INPCK))
389 || ISSET(err, TTY_FE)) {
390 if (ISSET(iflag, IGNPAR))
392 else if (ISSET(iflag, PARMRK)) {
394 if (tp->t_rawq.c_cc + tp->t_canq.c_cc >
397 clist_putc(0377 | TTY_QUOTE, &tp->t_rawq);
398 clist_putc(0 | TTY_QUOTE, &tp->t_rawq);
399 clist_putc(c | TTY_QUOTE, &tp->t_rawq);
406 if (!ISSET(tp->t_state, TS_TYPEN) && ISSET(iflag, ISTRIP))
408 if (!ISSET(lflag, EXTPROC)) {
410 * Check for literal nexting very first
412 if (ISSET(tp->t_state, TS_LNCH)) {
414 CLR(tp->t_state, TS_LNCH);
417 * Scan for special characters. This code
418 * is really just a big case statement with
419 * non-constant cases. The bottom of the
420 * case statement is labeled ``endcase'', so goto
421 * it after a case match, or similar.
425 * Control chars which aren't controlled
426 * by ICANON, ISIG, or IXON.
428 if (ISSET(lflag, IEXTEN)) {
429 if (CCEQ(cc[VLNEXT], c)) {
430 if (ISSET(lflag, ECHO)) {
431 if (ISSET(lflag, ECHOE)) {
432 (void)ttyoutput('^', tp);
433 (void)ttyoutput('\b', tp);
437 SET(tp->t_state, TS_LNCH);
440 if (CCEQ(cc[VDISCARD], c)) {
441 if (ISSET(lflag, FLUSHO))
442 CLR(tp->t_lflag, FLUSHO);
444 ttyflush(tp, FWRITE);
446 if (tp->t_rawq.c_cc + tp->t_canq.c_cc)
448 SET(tp->t_lflag, FLUSHO);
456 if (ISSET(lflag, ISIG)) {
457 if (CCEQ(cc[VINTR], c) || CCEQ(cc[VQUIT], c)) {
458 if (!ISSET(lflag, NOFLSH))
459 ttyflush(tp, FREAD | FWRITE);
462 CCEQ(cc[VINTR], c) ? SIGINT : SIGQUIT, 1);
465 if (CCEQ(cc[VSUSP], c)) {
466 if (!ISSET(lflag, NOFLSH))
469 pgsignal(tp->t_pgrp, SIGTSTP, 1);
474 * Handle start/stop characters.
476 if (ISSET(iflag, IXON)) {
477 if (CCEQ(cc[VSTOP], c)) {
478 if (!ISSET(tp->t_state, TS_TTSTOP)) {
479 SET(tp->t_state, TS_TTSTOP);
480 (*tp->t_stop)(tp, 0);
483 if (!CCEQ(cc[VSTART], c))
486 * if VSTART == VSTOP then toggle
490 if (CCEQ(cc[VSTART], c))
494 * IGNCR, ICRNL, & INLCR
497 if (ISSET(iflag, IGNCR))
499 else if (ISSET(iflag, ICRNL))
501 } else if (c == '\n' && ISSET(iflag, INLCR))
504 if (!ISSET(tp->t_lflag, EXTPROC) && ISSET(lflag, ICANON)) {
506 * From here on down canonical mode character
507 * processing takes place.
510 * erase or erase2 (^H / ^?)
512 if (CCEQ(cc[VERASE], c) || CCEQ(cc[VERASE2], c) ) {
514 ttyrub(clist_unputc(&tp->t_rawq), tp);
520 if (CCEQ(cc[VKILL], c)) {
521 if (ISSET(lflag, ECHOKE) &&
522 tp->t_rawq.c_cc == tp->t_rocount &&
523 !ISSET(lflag, ECHOPRT))
524 while (tp->t_rawq.c_cc)
525 ttyrub(clist_unputc(&tp->t_rawq), tp);
528 if (ISSET(lflag, ECHOK) ||
529 ISSET(lflag, ECHOKE))
534 CLR(tp->t_state, TS_LOCAL);
540 if (CCEQ(cc[VWERASE], c) && ISSET(lflag, IEXTEN)) {
546 while ((c = clist_unputc(&tp->t_rawq)) == ' ' || c == '\t')
551 * erase last char of word and remember the
552 * next chars type (for ALTWERASE)
555 c = clist_unputc(&tp->t_rawq);
558 if (c == ' ' || c == '\t') {
559 clist_putc(c, &tp->t_rawq);
568 c = clist_unputc(&tp->t_rawq);
571 } while (c != ' ' && c != '\t' &&
572 (!ISSET(lflag, ALTWERASE) || ISALPHA(c) == ctype));
573 clist_putc(c, &tp->t_rawq);
579 if (CCEQ(cc[VREPRINT], c) && ISSET(lflag, IEXTEN)) {
584 * ^T - kernel info and generate SIGINFO
586 if (CCEQ(cc[VSTATUS], c) && ISSET(lflag, IEXTEN)) {
587 if (ISSET(lflag, ISIG))
588 pgsignal(tp->t_pgrp, SIGINFO, 1);
589 if (!ISSET(lflag, NOKERNINFO))
593 if (CCEQ(cc[VCHECKPT], c) && ISSET(lflag, IEXTEN)) {
594 if (ISSET(lflag, ISIG))
595 pgsignal(tp->t_pgrp, SIGCKPT, 1);
600 * Check for input buffer overflow
602 if (tp->t_rawq.c_cc + tp->t_canq.c_cc >= MAX_INPUT) {
604 if (ISSET(iflag, IMAXBEL)) {
605 if (tp->t_outq.c_cc < tp->t_ohiwat)
606 (void)ttyoutput(CTRL('g'), tp);
611 if ( c == 0377 && ISSET(iflag, PARMRK) && !ISSET(iflag, ISTRIP)
612 && ISSET(iflag, IGNBRK|IGNPAR) != (IGNBRK|IGNPAR))
613 clist_putc(0377 | TTY_QUOTE, &tp->t_rawq);
616 * Put data char in q for user and
617 * wakeup on seeing a line delimiter.
619 if (clist_putc(c, &tp->t_rawq) >= 0) {
620 if (!ISSET(lflag, ICANON)) {
625 if (TTBREAKC(c, lflag)) {
627 catq(&tp->t_rawq, &tp->t_canq);
629 } else if (tp->t_rocount++ == 0)
630 tp->t_rocol = tp->t_column;
631 if (ISSET(tp->t_state, TS_ERASE)) {
633 * end of prterase \.../
635 CLR(tp->t_state, TS_ERASE);
636 (void)ttyoutput('/', tp);
640 if (CCEQ(cc[VEOF], c) && ISSET(lflag, ECHO)) {
642 * Place the cursor over the '^' of the ^D.
644 i = imin(2, tp->t_column - i);
646 (void)ttyoutput('\b', tp);
653 * IXANY means allow any character to restart output.
655 if (ISSET(tp->t_state, TS_TTSTOP) &&
656 !ISSET(iflag, IXANY) && cc[VSTART] != cc[VSTOP])
659 CLR(tp->t_lflag, FLUSHO);
660 CLR(tp->t_state, TS_TTSTOP);
662 return (ttstart(tp));
666 * Output a single character on a tty, doing output processing
667 * as needed (expanding tabs, newline processing, etc.).
668 * Returns < 0 if succeeds, otherwise returns char to resend.
680 if (!ISSET(oflag, OPOST)) {
681 if (ISSET(tp->t_lflag, FLUSHO))
683 if (clist_putc(c, &tp->t_outq))
690 * Do tab expansion if OXTABS is set. Special case if we external
691 * processing, we don't do the tab expansion because we'll probably
692 * get it wrong. If tab expansion needs to be done, let it happen
695 CLR(c, ~TTY_CHARMASK);
697 ISSET(oflag, OXTABS) && !ISSET(tp->t_lflag, EXTPROC)) {
698 c = 8 - (tp->t_column & 7);
699 if (!ISSET(tp->t_lflag, FLUSHO)) {
700 crit_enter(); /* Don't interrupt tabs. */
701 c -= b_to_q(" ", c, &tp->t_outq);
707 return (c ? -1 : '\t');
709 if (c == CEOT && ISSET(oflag, ONOEOT))
713 * Newline translation: if ONLCR is set,
714 * translate newline into "\r\n".
716 if (c == '\n' && ISSET(tp->t_oflag, ONLCR)) {
719 if (!ISSET(tp->t_lflag, FLUSHO) && clist_putc('\r', &tp->t_outq))
722 /* If OCRNL is set, translate "\r" into "\n". */
723 else if (c == '\r' && ISSET(tp->t_oflag, OCRNL))
725 /* If ONOCR is set, don't transmit CRs when on column 0. */
726 else if (c == '\r' && ISSET(tp->t_oflag, ONOCR) && tp->t_column == 0)
731 if (!ISSET(tp->t_lflag, FLUSHO) && clist_putc(c, &tp->t_outq))
743 if (ISSET(tp->t_oflag, ONLCR | ONLRET))
753 col = (col + 8) & ~7;
761 * Ioctls for all tty devices. Called after line-discipline specific ioctl
762 * has been called to do discipline-specific functions and/or reject any
763 * of these ioctl commands.
767 ttioctl(struct tty *tp, u_long cmd, void *data, int flag)
769 struct thread *td = curthread;
770 struct proc *p = td->td_proc;
775 /* If the ioctl involves modification, hang if in the background. */
799 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
809 while (isbackground(p, tp) && !(p->p_flag & P_PPWAIT) &&
810 !SIGISMEMBER(p->p_sigignore, SIGTTOU) &&
811 !SIGISMEMBER(p->p_sigmask, SIGTTOU)) {
812 if (p->p_pgrp->pg_jobc == 0)
814 pgsignal(p->p_pgrp, SIGTTOU, 1);
815 error = ttysleep(tp, &lbolt, PCATCH, "ttybg1",
823 switch (cmd) { /* Process the ioctl. */
824 case FIOASYNC: /* set/clear async i/o */
827 SET(tp->t_state, TS_ASYNC);
829 CLR(tp->t_state, TS_ASYNC);
832 case FIONREAD: /* get # bytes to read */
834 *(int *)data = ttnread(tp);
840 * Policy -- Don't allow FIOSETOWN on someone else's
843 if (tp->t_session != NULL && !isctty(p, tp))
846 error = fsetown(*(int *)data, &tp->t_sigio);
851 if (tp->t_session != NULL && !isctty(p, tp))
853 *(int *)data = fgetown(tp->t_sigio);
856 case TIOCEXCL: /* set exclusive use of tty */
858 SET(tp->t_state, TS_XCLUDE);
861 case TIOCFLUSH: { /* flush buffers */
862 int flags = *(int *)data;
865 flags = FREAD | FWRITE;
867 flags &= FREAD | FWRITE;
871 case TIOCCONS: /* become virtual console */
873 if (constty && constty != tp &&
874 ISSET(constty->t_state, TS_CONNECTED))
877 if ((error = suser(td)) != 0)
881 } else if (tp == constty)
884 case TIOCDRAIN: /* wait till output drained */
889 case TIOCGETA: { /* get termios struct */
890 struct termios *t = (struct termios *)data;
892 bcopy(&tp->t_termios, t, sizeof(struct termios));
895 case TIOCGETD: /* get line discipline */
896 *(int *)data = tp->t_line;
898 case TIOCGWINSZ: /* get window size */
899 *(struct winsize *)data = tp->t_winsize;
901 case TIOCGPGRP: /* get pgrp of tty */
904 *(int *)data = tp->t_pgrp ? tp->t_pgrp->pg_id : NO_PID;
907 case TIOCHPCL: /* hang up on last close */
909 SET(tp->t_cflag, HUPCL);
913 case TIOCNXCL: /* reset exclusive use of tty */
915 CLR(tp->t_state, TS_XCLUDE);
918 case TIOCOUTQ: /* output queue size */
919 *(int *)data = tp->t_outq.c_cc;
921 case TIOCSETA: /* set termios struct */
922 case TIOCSETAW: /* drain output, set */
923 case TIOCSETAF: { /* drn out, fls in, set */
924 struct termios *t = (struct termios *)data;
926 if (t->c_ispeed == 0)
927 t->c_ispeed = t->c_ospeed;
928 if (t->c_ispeed == 0)
929 t->c_ispeed = tp->t_ospeed;
930 if (t->c_ispeed == 0)
933 if (cmd == TIOCSETAW || cmd == TIOCSETAF) {
939 if (cmd == TIOCSETAF)
942 if (!ISSET(t->c_cflag, CIGNORE)) {
944 * Set device hardware.
946 if (tp->t_param && (error = (*tp->t_param)(tp, t))) {
950 if (ISSET(t->c_cflag, CLOCAL) &&
951 !ISSET(tp->t_cflag, CLOCAL)) {
953 * XXX disconnections would be too hard to
954 * get rid of without this kludge. The only
955 * way to get rid of controlling terminals
956 * is to exit from the session leader.
958 CLR(tp->t_state, TS_ZOMBIE);
960 wakeup(TSA_CARR_ON(tp));
964 if ((ISSET(tp->t_state, TS_CARR_ON) ||
965 ISSET(t->c_cflag, CLOCAL)) &&
966 !ISSET(tp->t_state, TS_ZOMBIE))
967 SET(tp->t_state, TS_CONNECTED);
969 CLR(tp->t_state, TS_CONNECTED);
970 tp->t_cflag = t->c_cflag;
971 tp->t_ispeed = t->c_ispeed;
972 if (t->c_ospeed != 0)
973 tp->t_ospeed = t->c_ospeed;
976 if (ISSET(t->c_lflag, ICANON) != ISSET(tp->t_lflag, ICANON) &&
978 if (ISSET(t->c_lflag, ICANON))
979 SET(tp->t_lflag, PENDIN);
982 * XXX we really shouldn't allow toggling
983 * ICANON while we're in a non-termios line
984 * discipline. Now we have to worry about
985 * panicing for a null queue.
987 if (tp->t_canq.c_cbreserved > 0 &&
988 tp->t_rawq.c_cbreserved > 0) {
989 catq(&tp->t_rawq, &tp->t_canq);
991 * XXX the queue limits may be
992 * different, so the old queue
993 * swapping method no longer works.
995 catq(&tp->t_canq, &tp->t_rawq);
997 CLR(tp->t_lflag, PENDIN);
1001 tp->t_iflag = t->c_iflag;
1002 tp->t_oflag = t->c_oflag;
1004 * Make the EXTPROC bit read only.
1006 if (ISSET(tp->t_lflag, EXTPROC))
1007 SET(t->c_lflag, EXTPROC);
1009 CLR(t->c_lflag, EXTPROC);
1010 tp->t_lflag = t->c_lflag | ISSET(tp->t_lflag, PENDIN);
1011 if (t->c_cc[VMIN] != tp->t_cc[VMIN] ||
1012 t->c_cc[VTIME] != tp->t_cc[VTIME])
1014 bcopy(t->c_cc, tp->t_cc, sizeof(t->c_cc));
1018 case TIOCSETD: { /* set line discipline */
1019 int t = *(int *)data;
1020 cdev_t device = tp->t_dev;
1022 if ((u_int)t >= nlinesw)
1024 if (t != tp->t_line) {
1026 (*linesw[tp->t_line].l_close)(tp, flag);
1027 error = (*linesw[t].l_open)(device, tp);
1029 (void)(*linesw[tp->t_line].l_open)(device, tp);
1038 case TIOCSTART: /* start output, like ^Q */
1040 if (ISSET(tp->t_state, TS_TTSTOP) ||
1041 ISSET(tp->t_lflag, FLUSHO)) {
1042 CLR(tp->t_lflag, FLUSHO);
1043 CLR(tp->t_state, TS_TTSTOP);
1048 case TIOCSTI: /* simulate terminal input */
1049 if ((flag & FREAD) == 0 && suser(td))
1051 if (!isctty(p, tp) && suser(td))
1054 (*linesw[tp->t_line].l_rint)(*(u_char *)data, tp);
1057 case TIOCSTOP: /* stop output, like ^S */
1059 if (!ISSET(tp->t_state, TS_TTSTOP)) {
1060 SET(tp->t_state, TS_TTSTOP);
1061 (*tp->t_stop)(tp, 0);
1065 case TIOCSCTTY: /* become controlling tty */
1066 /* Session ctty vnode pointer set in vnode layer. */
1067 if (!SESS_LEADER(p) ||
1068 ((p->p_session->s_ttyvp || tp->t_session) &&
1069 (tp->t_session != p->p_session)))
1071 tp->t_session = p->p_session;
1072 tp->t_pgrp = p->p_pgrp;
1073 p->p_session->s_ttyp = tp;
1074 p->p_flag |= P_CONTROLT;
1076 case TIOCSPGRP: { /* set pgrp of tty */
1077 struct pgrp *pgrp = pgfind(*(int *)data);
1081 else if (pgrp == NULL || pgrp->pg_session != p->p_session)
1086 case TIOCSTAT: /* simulate control-T */
1091 case TIOCSWINSZ: /* set window size */
1092 if (bcmp((caddr_t)&tp->t_winsize, data,
1093 sizeof (struct winsize))) {
1094 tp->t_winsize = *(struct winsize *)data;
1095 pgsignal(tp->t_pgrp, SIGWINCH, 1);
1098 case TIOCSDRAINWAIT:
1102 tp->t_timeout = *(int *)data * hz;
1103 wakeup(TSA_OCOMPLETE(tp));
1104 wakeup(TSA_OLOWAT(tp));
1106 case TIOCGDRAINWAIT:
1107 *(int *)data = tp->t_timeout / hz;
1110 #if defined(COMPAT_43) || defined(COMPAT_SUNOS)
1111 return (ttcompat(tp, cmd, data, flag));
1120 ttypoll(struct dev_poll_args *ap)
1122 cdev_t dev = ap->a_head.a_dev;
1123 int events = ap->a_events;
1128 /* XXX used to return ENXIO, but that means true! */
1130 ap->a_events = (events & (POLLIN | POLLOUT | POLLRDNORM |
1131 POLLWRNORM)) | POLLHUP;
1136 if (events & (POLLIN | POLLRDNORM)) {
1137 if (ttnread(tp) > 0 || ISSET(tp->t_state, TS_ZOMBIE))
1138 revents |= events & (POLLIN | POLLRDNORM);
1140 selrecord(curthread, &tp->t_rsel);
1142 if (events & (POLLOUT | POLLWRNORM)) {
1143 if ((tp->t_outq.c_cc <= tp->t_olowat &&
1144 ISSET(tp->t_state, TS_CONNECTED))
1145 || ISSET(tp->t_state, TS_ZOMBIE))
1146 revents |= events & (POLLOUT | POLLWRNORM);
1148 selrecord(curthread, &tp->t_wsel);
1151 ap->a_events = revents;
1155 static struct filterops ttyread_filtops =
1156 { 1, NULL, filt_ttyrdetach, filt_ttyread };
1157 static struct filterops ttywrite_filtops =
1158 { 1, NULL, filt_ttywdetach, filt_ttywrite };
1161 ttykqfilter(struct dev_kqfilter_args *ap)
1163 cdev_t dev = ap->a_head.a_dev;
1164 struct knote *kn = ap->a_kn;
1165 struct tty *tp = dev->si_tty;
1166 struct klist *klist;
1169 switch (kn->kn_filter) {
1171 klist = &tp->t_rsel.si_note;
1172 kn->kn_fop = &ttyread_filtops;
1175 klist = &tp->t_wsel.si_note;
1176 kn->kn_fop = &ttywrite_filtops;
1183 kn->kn_hook = (caddr_t)dev;
1186 SLIST_INSERT_HEAD(klist, kn, kn_selnext);
1193 filt_ttyrdetach(struct knote *kn)
1195 struct tty *tp = ((cdev_t)kn->kn_hook)->si_tty;
1198 SLIST_REMOVE(&tp->t_rsel.si_note, kn, knote, kn_selnext);
1203 filt_ttyread(struct knote *kn, long hint)
1205 struct tty *tp = ((cdev_t)kn->kn_hook)->si_tty;
1207 kn->kn_data = ttnread(tp);
1208 if (ISSET(tp->t_state, TS_ZOMBIE)) {
1209 kn->kn_flags |= EV_EOF;
1212 return (kn->kn_data > 0);
1216 filt_ttywdetach(struct knote *kn)
1218 struct tty *tp = ((cdev_t)kn->kn_hook)->si_tty;
1221 SLIST_REMOVE(&tp->t_wsel.si_note, kn, knote, kn_selnext);
1226 filt_ttywrite(kn, hint)
1230 struct tty *tp = ((cdev_t)kn->kn_hook)->si_tty;
1232 kn->kn_data = tp->t_outq.c_cc;
1233 if (ISSET(tp->t_state, TS_ZOMBIE))
1235 return (kn->kn_data <= tp->t_olowat &&
1236 ISSET(tp->t_state, TS_CONNECTED));
1240 * Must be called while in a critical section.
1248 if (ISSET(tp->t_lflag, PENDIN))
1250 nread = tp->t_canq.c_cc;
1251 if (!ISSET(tp->t_lflag, ICANON)) {
1252 nread += tp->t_rawq.c_cc;
1253 if (nread < tp->t_cc[VMIN] && tp->t_cc[VTIME] == 0)
1260 * Wait for output to drain.
1270 while ((tp->t_outq.c_cc || ISSET(tp->t_state, TS_BUSY)) &&
1271 ISSET(tp->t_state, TS_CONNECTED) && tp->t_oproc) {
1273 if ((tp->t_outq.c_cc || ISSET(tp->t_state, TS_BUSY)) &&
1274 ISSET(tp->t_state, TS_CONNECTED)) {
1275 SET(tp->t_state, TS_SO_OCOMPLETE);
1276 error = ttysleep(tp, TSA_OCOMPLETE(tp),
1280 if (error == EWOULDBLOCK)
1287 if (!error && (tp->t_outq.c_cc || ISSET(tp->t_state, TS_BUSY)))
1294 * Flush if successfully wait.
1302 if ((error = ttywait(tp)) == 0)
1303 ttyflush(tp, FREAD);
1308 * Flush tty read and/or write queues, notifying anyone waiting.
1320 FLUSHQ(&tp->t_outq);
1321 CLR(tp->t_state, TS_TTSTOP);
1323 (*tp->t_stop)(tp, rw);
1325 FLUSHQ(&tp->t_canq);
1326 FLUSHQ(&tp->t_rawq);
1327 CLR(tp->t_lflag, PENDIN);
1330 CLR(tp->t_state, TS_LOCAL);
1332 if (ISSET(tp->t_state, TS_TBLOCK)) {
1334 FLUSHQ(&tp->t_outq);
1338 * Don't let leave any state that might clobber the
1339 * next line discipline (although we should do more
1340 * to send the START char). Not clearing the state
1341 * may have caused the "putc to a clist with no
1342 * reserved cblocks" panic/printf.
1344 CLR(tp->t_state, TS_TBLOCK);
1346 #if 0 /* forget it, sleeping isn't always safe and we don't know when it is */
1347 if (ISSET(tp->t_iflag, IXOFF)) {
1349 * XXX wait a bit in the hope that the stop
1350 * character (if any) will go out. Waiting
1351 * isn't good since it allows races. This
1352 * will be fixed when the stop character is
1353 * put in a special queue. Don't bother with
1354 * the checks in ttywait() since the timeout
1357 SET(tp->t_state, TS_SO_OCOMPLETE);
1358 ttysleep(tp, TSA_OCOMPLETE(tp), 0,
1361 * Don't try sending the stop character again.
1363 CLR(tp->t_state, TS_TBLOCK);
1370 FLUSHQ(&tp->t_outq);
1377 * Copy in the default termios characters.
1384 bcopy(ttydefchars, t->c_cc, sizeof t->c_cc);
1395 termioschars(&tp->t_termios);
1399 * Handle input high water. Send stop character for the IXOFF case. Turn
1400 * on our input flow control bit and propagate the changes to the driver.
1401 * XXX the stop character should be put in a special high priority queue.
1408 SET(tp->t_state, TS_TBLOCK);
1409 if (ISSET(tp->t_iflag, IXOFF) && tp->t_cc[VSTOP] != _POSIX_VDISABLE &&
1410 clist_putc(tp->t_cc[VSTOP], &tp->t_outq) != 0)
1411 CLR(tp->t_state, TS_TBLOCK); /* try again later */
1416 * Handle input low water. Send start character for the IXOFF case. Turn
1417 * off our input flow control bit and propagate the changes to the driver.
1418 * XXX the start character should be put in a special high priority queue.
1425 CLR(tp->t_state, TS_TBLOCK);
1426 if (ISSET(tp->t_iflag, IXOFF) && tp->t_cc[VSTART] != _POSIX_VDISABLE &&
1427 clist_putc(tp->t_cc[VSTART], &tp->t_outq) != 0)
1428 SET(tp->t_state, TS_TBLOCK); /* try again later */
1433 /* Not used by any current (i386) drivers. */
1435 * Restart after an inter-char delay.
1443 KASSERT(tp_arg != NULL, ("ttrstrt"));
1447 CLR(tp->t_state, TS_TIMEOUT);
1458 if (tp->t_oproc != NULL) /* XXX: Kludge for pty. */
1464 * "close" a line discipline
1472 if (flag & FNONBLOCK || ttywflush(tp))
1473 ttyflush(tp, FREAD | FWRITE);
1478 * Handle modem control transition on a tty.
1479 * Flag indicates new state of carrier.
1480 * Returns 0 if the line should be turned off, otherwise 1.
1488 if (ISSET(tp->t_state, TS_CARR_ON) && ISSET(tp->t_cflag, MDMBUF)) {
1490 * MDMBUF: do flow control according to carrier flag
1491 * XXX TS_CAR_OFLOW doesn't do anything yet. TS_TTSTOP
1492 * works if IXON and IXANY are clear.
1495 CLR(tp->t_state, TS_CAR_OFLOW);
1496 CLR(tp->t_state, TS_TTSTOP);
1498 } else if (!ISSET(tp->t_state, TS_CAR_OFLOW)) {
1499 SET(tp->t_state, TS_CAR_OFLOW);
1500 SET(tp->t_state, TS_TTSTOP);
1501 (*tp->t_stop)(tp, 0);
1503 } else if (flag == 0) {
1507 CLR(tp->t_state, TS_CARR_ON);
1508 if (ISSET(tp->t_state, TS_ISOPEN) &&
1509 !ISSET(tp->t_cflag, CLOCAL)) {
1510 SET(tp->t_state, TS_ZOMBIE);
1511 CLR(tp->t_state, TS_CONNECTED);
1512 if (tp->t_session && tp->t_session->s_leader)
1513 ksignal(tp->t_session->s_leader, SIGHUP);
1514 ttyflush(tp, FREAD | FWRITE);
1521 SET(tp->t_state, TS_CARR_ON);
1522 if (!ISSET(tp->t_state, TS_ZOMBIE))
1523 SET(tp->t_state, TS_CONNECTED);
1524 wakeup(TSA_CARR_ON(tp));
1532 * Reinput pending characters after state switch
1533 * call from a critical section.
1542 CLR(tp->t_lflag, PENDIN);
1543 SET(tp->t_state, TS_TYPEN);
1545 * XXX this assumes too much about clist internals. It may even
1546 * fail if the cblock slush pool is empty. We can't allocate more
1547 * cblocks here because we are called from an interrupt handler
1548 * and clist_alloc_cblocks() can wait.
1551 bzero(&tp->t_rawq, sizeof tp->t_rawq);
1552 tp->t_rawq.c_cbmax = tq.c_cbmax;
1553 tp->t_rawq.c_cbreserved = tq.c_cbreserved;
1554 while ((c = clist_getc(&tq)) >= 0)
1556 CLR(tp->t_state, TS_TYPEN);
1560 * Process a read call on a tty device.
1563 ttread(tp, uio, flag)
1571 cc_t *cc = tp->t_cc;
1573 int first, error = 0;
1574 int has_stime = 0, last_cc = 0;
1575 long slp = 0; /* XXX this should be renamed `timo'. */
1576 struct timeval stime;
1580 lflag = tp->t_lflag;
1582 * take pending input first
1584 if (ISSET(lflag, PENDIN)) {
1586 splz(); /* reduce latency */
1587 lflag = tp->t_lflag; /* XXX ttypend() clobbers it */
1591 * Hang process if it's in the background.
1593 if ((pp = curproc) && isbackground(pp, tp)) {
1595 if (SIGISMEMBER(pp->p_sigignore, SIGTTIN) ||
1596 SIGISMEMBER(pp->p_sigmask, SIGTTIN) ||
1597 (pp->p_flag & P_PPWAIT) || pp->p_pgrp->pg_jobc == 0)
1599 pgsignal(pp->p_pgrp, SIGTTIN, 1);
1600 error = ttysleep(tp, &lbolt, PCATCH, "ttybg2", 0);
1606 if (ISSET(tp->t_state, TS_ZOMBIE)) {
1608 return (0); /* EOF */
1612 * If canonical, use the canonical queue,
1613 * else use the raw queue.
1615 * (should get rid of clists...)
1617 qp = ISSET(lflag, ICANON) ? &tp->t_canq : &tp->t_rawq;
1619 if (flag & IO_NDELAY) {
1622 if (!ISSET(lflag, ICANON) && cc[VMIN] == 0) {
1627 return (EWOULDBLOCK);
1629 if (!ISSET(lflag, ICANON)) {
1632 struct timeval timecopy;
1635 * Check each of the four combinations.
1636 * (m > 0 && t == 0) is the normal read case.
1637 * It should be fairly efficient, so we check that and its
1638 * companion case (m == 0 && t == 0) first.
1639 * For the other two cases, we compute the target sleep time
1648 /* m, t and qp->c_cc are all 0. 0 is enough input. */
1652 t *= 100000; /* time in us */
1653 #define diff(t1, t2) (((t1).tv_sec - (t2).tv_sec) * 1000000 + \
1654 ((t1).tv_usec - (t2).tv_usec))
1660 getmicrotime(&timecopy);
1662 /* first character, start timer */
1666 } else if (qp->c_cc > last_cc) {
1667 /* got a character, restart timer */
1671 /* nothing, check expiration */
1672 slp = t - diff(timecopy, stime);
1677 } else { /* m == 0 */
1680 getmicrotime(&timecopy);
1686 slp = t - diff(timecopy, stime);
1688 /* Timed out, but 0 is enough input. */
1696 * Rounding down may make us wake up just short
1697 * of the target, so we round up.
1698 * The formula is ceiling(slp * hz/1000000).
1699 * 32-bit arithmetic is enough for hz < 169.
1700 * XXX see tvtohz() for how to avoid overflow if hz
1701 * is large (divide by `tick' and/or arrange to
1702 * use tvtohz() if hz is large).
1704 slp = (long) (((u_long)slp * hz) + 999999) / 1000000;
1707 if (qp->c_cc <= 0) {
1710 * There is no input, or not enough input and we can block.
1712 error = ttysleep(tp, TSA_HUP_OR_INPUT(tp), PCATCH,
1713 ISSET(tp->t_state, TS_CONNECTED) ?
1714 "ttyin" : "ttyhup", (int)slp);
1716 if (error == EWOULDBLOCK)
1721 * XXX what happens if another process eats some input
1722 * while we are asleep (not just here)? It would be
1723 * safest to detect changes and reset our state variables
1724 * (has_stime and last_cc).
1732 * Input present, check for input mapping and processing.
1735 if (ISSET(lflag, ICANON | ISIG))
1741 icc = imin(uio->uio_resid, IBUFSIZ);
1742 icc = q_to_b(qp, ibuf, icc);
1748 error = uiomove(ibuf, icc, uio);
1750 * XXX if there was an error then we should ungetc() the
1751 * unmoved chars and reduce icc here.
1755 if (uio->uio_resid == 0)
1769 * delayed suspend (^Y)
1771 if (CCEQ(cc[VDSUSP], c) &&
1772 ISSET(lflag, IEXTEN | ISIG) == (IEXTEN | ISIG)) {
1773 pgsignal(tp->t_pgrp, SIGTSTP, 1);
1775 error = ttysleep(tp, &lbolt, PCATCH,
1784 * Interpret EOF only in canonical mode.
1786 if (CCEQ(cc[VEOF], c) && ISSET(lflag, ICANON))
1789 * Give user character.
1791 error = ureadc(c, uio);
1793 /* XXX should ungetc(c, qp). */
1795 if (uio->uio_resid == 0)
1798 * In canonical mode check for a "break character"
1799 * marking the end of a "line of input".
1801 if (ISSET(lflag, ICANON) && TTBREAKC(c, lflag))
1808 * Look to unblock input now that (presumably)
1809 * the input queue has gone down.
1812 if (ISSET(tp->t_state, TS_TBLOCK) &&
1813 tp->t_rawq.c_cc + tp->t_canq.c_cc <= tp->t_ilowat)
1821 * Check the output queue on tp for space for a kernel message (from uprintf
1822 * or tprintf). Allow some space over the normal hiwater mark so we don't
1823 * lose messages due to normal flow control, but don't let the tty run amok.
1824 * Sleeps here are not interruptible, but we return prematurely if new signals
1828 ttycheckoutq(tp, wait)
1835 hiwat = tp->t_ohiwat;
1836 SIGEMPTYSET(oldmask);
1839 oldmask = curproc->p_siglist;
1840 if (tp->t_outq.c_cc > hiwat + OBUFSIZ + 100) {
1841 while (tp->t_outq.c_cc > hiwat) {
1843 if (tp->t_outq.c_cc <= hiwat)
1845 if (!(wait && SIGSETEQ(curproc->p_siglist, oldmask))) {
1849 SET(tp->t_state, TS_SO_OLOWAT);
1850 tsleep(TSA_OLOWAT(tp), 0, "ttoutq", hz);
1858 * Process a write call on a tty device.
1861 ttwrite(tp, uio, flag)
1869 int i, hiwat, cnt, error;
1872 hiwat = tp->t_ohiwat;
1873 cnt = uio->uio_resid;
1878 if (ISSET(tp->t_state, TS_ZOMBIE)) {
1880 if (uio->uio_resid == cnt)
1884 if (!ISSET(tp->t_state, TS_CONNECTED)) {
1885 if (flag & IO_NDELAY) {
1887 error = EWOULDBLOCK;
1890 error = ttysleep(tp, TSA_CARR_ON(tp), PCATCH, "ttydcd", 0);
1899 * Hang the process if it's in the background.
1901 if ((pp = curproc) && isbackground(pp, tp) &&
1902 ISSET(tp->t_lflag, TOSTOP) && !(pp->p_flag & P_PPWAIT) &&
1903 !SIGISMEMBER(pp->p_sigignore, SIGTTOU) &&
1904 !SIGISMEMBER(pp->p_sigmask, SIGTTOU)) {
1905 if (pp->p_pgrp->pg_jobc == 0) {
1909 pgsignal(pp->p_pgrp, SIGTTOU, 1);
1910 error = ttysleep(tp, &lbolt, PCATCH, "ttybg4", 0);
1916 * Process the user's data in at most OBUFSIZ chunks. Perform any
1917 * output translation. Keep track of high water mark, sleep on
1918 * overflow awaiting device aid in acquiring new space.
1920 while (uio->uio_resid > 0 || cc > 0) {
1921 if (ISSET(tp->t_lflag, FLUSHO)) {
1925 if (tp->t_outq.c_cc > hiwat)
1928 * Grab a hunk of data from the user, unless we have some
1929 * leftover from last time.
1932 cc = imin(uio->uio_resid, OBUFSIZ);
1934 error = uiomove(cp, cc, uio);
1941 * If nothing fancy need be done, grab those characters we
1942 * can handle without any of ttyoutput's processing and
1943 * just transfer them to the output q. For those chars
1944 * which require special processing (as indicated by the
1945 * bits in char_type), call ttyoutput. After processing
1946 * a hunk of data, look for FLUSHO so ^O's will take effect
1950 if (!ISSET(tp->t_oflag, OPOST))
1953 ce = cc - scanc((u_int)cc, (u_char *)cp,
1954 char_type, CCLASSMASK);
1956 * If ce is zero, then we're processing
1957 * a special character through ttyoutput.
1961 if (ttyoutput(*cp, tp) >= 0) {
1962 /* No Clists, wait a bit. */
1964 if (flag & IO_NDELAY) {
1965 error = EWOULDBLOCK;
1968 error = ttysleep(tp, &lbolt,
1977 if (ISSET(tp->t_lflag, FLUSHO) ||
1978 tp->t_outq.c_cc > hiwat)
1984 * A bunch of normal characters have been found.
1985 * Transfer them en masse to the output queue and
1986 * continue processing at the top of the loop.
1987 * If there are any further characters in this
1988 * <= OBUFSIZ chunk, the first should be a character
1989 * requiring special handling by ttyoutput.
1992 i = b_to_q(cp, ce, &tp->t_outq);
1995 cp += ce, cc -= ce, tk_nout += ce;
1998 /* No Clists, wait a bit. */
2000 if (flag & IO_NDELAY) {
2001 error = EWOULDBLOCK;
2004 error = ttysleep(tp, &lbolt, PCATCH,
2010 if (ISSET(tp->t_lflag, FLUSHO) ||
2011 tp->t_outq.c_cc > hiwat)
2018 * If cc is nonzero, we leave the uio structure inconsistent, as the
2019 * offset and iov pointers have moved forward, but it doesn't matter
2020 * (the call will either return short or restart with a new uio).
2022 uio->uio_resid += cc;
2029 * This can only occur if FLUSHO is set in t_lflag,
2030 * or if ttstart/oproc is synchronous (or very fast).
2032 if (tp->t_outq.c_cc <= hiwat) {
2036 if (flag & IO_NDELAY) {
2038 uio->uio_resid += cc;
2039 return (uio->uio_resid == cnt ? EWOULDBLOCK : 0);
2041 SET(tp->t_state, TS_SO_OLOWAT);
2042 error = ttysleep(tp, TSA_OLOWAT(tp), PCATCH, "ttywri", tp->t_timeout);
2044 if (error == EWOULDBLOCK)
2052 * Rubout one character from the rawq of tp
2053 * as cleanly as possible.
2064 if (!ISSET(tp->t_lflag, ECHO) || ISSET(tp->t_lflag, EXTPROC))
2066 CLR(tp->t_lflag, FLUSHO);
2067 if (ISSET(tp->t_lflag, ECHOE)) {
2068 if (tp->t_rocount == 0) {
2070 * Screwed by ttwrite; retype
2075 if (c == ('\t' | TTY_QUOTE) || c == ('\n' | TTY_QUOTE))
2078 CLR(c, ~TTY_CHARMASK);
2079 switch (CCLASS(c)) {
2088 if (ISSET(tp->t_lflag, ECHOCTL))
2092 if (tp->t_rocount < tp->t_rawq.c_cc) {
2097 savecol = tp->t_column;
2098 SET(tp->t_state, TS_CNTTB);
2099 SET(tp->t_lflag, FLUSHO);
2100 tp->t_column = tp->t_rocol;
2101 cp = tp->t_rawq.c_cf;
2103 tabc = *cp; /* XXX FIX NEXTC */
2104 for (; cp; cp = nextc(&tp->t_rawq, cp, &tabc))
2106 CLR(tp->t_lflag, FLUSHO);
2107 CLR(tp->t_state, TS_CNTTB);
2110 /* savecol will now be length of the tab. */
2111 savecol -= tp->t_column;
2112 tp->t_column += savecol;
2114 savecol = 8; /* overflow screw */
2115 while (--savecol >= 0)
2116 (void)ttyoutput('\b', tp);
2119 #define PANICSTR "ttyrub: would panic c = %d, val = %d\n"
2120 (void)printf(PANICSTR, c, CCLASS(c));
2122 panic(PANICSTR, c, CCLASS(c));
2126 } else if (ISSET(tp->t_lflag, ECHOPRT)) {
2127 if (!ISSET(tp->t_state, TS_ERASE)) {
2128 SET(tp->t_state, TS_ERASE);
2129 (void)ttyoutput('\\', tp);
2133 ttyecho(tp->t_cc[VERASE], tp);
2135 * This code may be executed not only when an ERASE key
2136 * is pressed, but also when ^U (KILL) or ^W (WERASE) are.
2137 * So, I didn't think it was worthwhile to pass the extra
2138 * information (which would need an extra parameter,
2139 * changing every call) needed to distinguish the ERASE2
2140 * case from the ERASE.
2147 * Back over cnt characters, erasing them.
2156 (void)ttyoutput('\b', tp);
2157 (void)ttyoutput(' ', tp);
2158 (void)ttyoutput('\b', tp);
2164 * Reprint the rawq line. Note, it is assumed that c_cc has already
2174 /* Echo the reprint character. */
2175 if (tp->t_cc[VREPRINT] != _POSIX_VDISABLE)
2176 ttyecho(tp->t_cc[VREPRINT], tp);
2178 (void)ttyoutput('\n', tp);
2182 * FIX: NEXTC IS BROKEN - DOESN'T CHECK QUOTE
2183 * BIT OF FIRST CHAR.
2186 for (cp = tp->t_canq.c_cf, c = (cp != NULL ? *cp : 0);
2187 cp != NULL; cp = nextc(&tp->t_canq, cp, &c))
2189 for (cp = tp->t_rawq.c_cf, c = (cp != NULL ? *cp : 0);
2190 cp != NULL; cp = nextc(&tp->t_rawq, cp, &c))
2192 CLR(tp->t_state, TS_ERASE);
2195 tp->t_rocount = tp->t_rawq.c_cc;
2200 * Echo a typed character to the terminal.
2208 if (!ISSET(tp->t_state, TS_CNTTB))
2209 CLR(tp->t_lflag, FLUSHO);
2210 if ((!ISSET(tp->t_lflag, ECHO) &&
2211 (c != '\n' || !ISSET(tp->t_lflag, ECHONL))) ||
2212 ISSET(tp->t_lflag, EXTPROC))
2214 if (ISSET(tp->t_lflag, ECHOCTL) &&
2215 ((ISSET(c, TTY_CHARMASK) <= 037 && c != '\t' && c != '\n') ||
2216 ISSET(c, TTY_CHARMASK) == 0177)) {
2217 (void)ttyoutput('^', tp);
2218 CLR(c, ~TTY_CHARMASK);
2224 (void)ttyoutput(c, tp);
2228 * Wake up any readers on a tty.
2235 if (tp->t_rsel.si_pid != 0)
2236 selwakeup(&tp->t_rsel);
2237 if (ISSET(tp->t_state, TS_ASYNC) && tp->t_sigio != NULL)
2238 pgsigio(tp->t_sigio, SIGIO, (tp->t_session != NULL));
2239 wakeup(TSA_HUP_OR_INPUT(tp));
2240 KNOTE(&tp->t_rsel.si_note, 0);
2244 * Wake up any writers on a tty.
2251 if (tp->t_wsel.si_pid != 0 && tp->t_outq.c_cc <= tp->t_olowat)
2252 selwakeup(&tp->t_wsel);
2253 if (ISSET(tp->t_state, TS_ASYNC) && tp->t_sigio != NULL)
2254 pgsigio(tp->t_sigio, SIGIO, (tp->t_session != NULL));
2255 if (ISSET(tp->t_state, TS_BUSY | TS_SO_OCOMPLETE) ==
2256 TS_SO_OCOMPLETE && tp->t_outq.c_cc == 0) {
2257 CLR(tp->t_state, TS_SO_OCOMPLETE);
2258 wakeup(TSA_OCOMPLETE(tp));
2260 if (ISSET(tp->t_state, TS_SO_OLOWAT) &&
2261 tp->t_outq.c_cc <= tp->t_olowat) {
2262 CLR(tp->t_state, TS_SO_OLOWAT);
2263 wakeup(TSA_OLOWAT(tp));
2265 KNOTE(&tp->t_wsel.si_note, 0);
2269 * Look up a code for a specified speed in a conversion table;
2270 * used by drivers to map software speed values to hardware parameters.
2273 ttspeedtab(speed, table)
2275 struct speedtab *table;
2278 for ( ; table->sp_speed != -1; table++)
2279 if (table->sp_speed == speed)
2280 return (table->sp_code);
2285 * Set input and output watermarks and buffer sizes. For input, the
2286 * high watermark is about one second's worth of input above empty, the
2287 * low watermark is slightly below high water, and the buffer size is a
2288 * driver-dependent amount above high water. For output, the watermarks
2289 * are near the ends of the buffer, with about 1 second's worth of input
2290 * between them. All this only applies to the standard line discipline.
2296 int cps, ttmaxhiwat, x;
2299 clist_alloc_cblocks(&tp->t_canq, TTYHOG, 512);
2300 switch (tp->t_ispeedwat) {
2302 cps = tp->t_ispeed / 10;
2306 * This case is for old drivers that don't know about
2307 * t_ispeedwat. Arrange for them to get the old buffer
2308 * sizes and watermarks.
2310 cps = TTYHOG - 2 * 256;
2311 tp->t_ififosize = 2 * 256;
2314 cps = tp->t_ispeedwat / 10;
2318 tp->t_ilowat = 7 * cps / 8;
2319 x = cps + tp->t_ififosize;
2320 clist_alloc_cblocks(&tp->t_rawq, x, x);
2323 switch (tp->t_ospeedwat) {
2325 cps = tp->t_ospeed / 10;
2326 ttmaxhiwat = 2 * TTMAXHIWAT;
2329 cps = tp->t_ospeed / 10;
2330 ttmaxhiwat = TTMAXHIWAT;
2333 cps = tp->t_ospeedwat / 10;
2334 ttmaxhiwat = 8 * TTMAXHIWAT;
2337 #define CLAMP(x, h, l) ((x) > h ? h : ((x) < l) ? l : (x))
2338 tp->t_olowat = x = CLAMP(cps / 2, TTMAXLOWAT, TTMINLOWAT);
2340 x = CLAMP(x, ttmaxhiwat, TTMINHIWAT); /* XXX clamps are too magic */
2341 tp->t_ohiwat = roundup(x, CBSIZE); /* XXX for compat */
2342 x = imax(tp->t_ohiwat, TTMAXHIWAT); /* XXX for compat/safety */
2344 clist_alloc_cblocks(&tp->t_outq, x, x);
2349 * Report on state of foreground process group.
2355 struct proc *p, *pick;
2356 struct timeval utime, stime;
2359 if (ttycheckoutq(tp,0) == 0)
2363 * We always print the load average, then figure out what else to
2364 * print based on the state of the current process group.
2366 tmp = (averunnable.ldavg[0] * 100 + FSCALE / 2) >> FSHIFT;
2367 ttyprintf(tp, "load: %d.%02d ", tmp / 100, tmp % 100);
2369 if (tp->t_session == NULL) {
2370 ttyprintf(tp, "not a controlling terminal\n");
2371 } else if (tp->t_pgrp == NULL) {
2372 ttyprintf(tp, "no foreground process group\n");
2373 } else if ((p = LIST_FIRST(&tp->t_pgrp->pg_members)) == 0) {
2374 ttyprintf(tp, "empty foreground process group\n");
2377 * Pick an interesting process. Note that certain elements,
2378 * in particular the wmesg, require a critical section for
2379 * safe access (YYY and we are still not MP safe).
2381 * NOTE: p_wmesg is p_thread->td_wmesg, and p_comm is
2382 * p_thread->td_comm.
2392 /* XXX lwp should compare lwps */
2394 for (pick = NULL; p != 0; p = LIST_NEXT(p, p_pglist)) {
2395 if (proc_compare(pick, p))
2400 * Figure out what wait/process-state message, and command
2403 if (pick->p_flag & P_WEXIT)
2405 else if (pick->p_stat == SRUN)
2407 else if (pick->p_stat == SIDL)
2409 else if (pick->p_wmesg) /* p_thread must not be NULL */
2410 str = pick->p_wmesg;
2414 snprintf(buf, sizeof(buf), "cmd: %s %d [%s]",
2415 pick->p_comm, pick->p_pid, str);
2418 * Calculate cpu usage, percent cpu, and cmsz. Note that
2419 * 'pick' becomes invalid the moment we exit the critical
2422 if (pick->p_thread && (pick->p_flag & P_SWAPPEDOUT) == 0) {
2423 calcru(pick, &utime, &stime, NULL);
2429 pctcpu = (pick->p_pctcpu * 10000 + FSCALE / 2) >> FSHIFT;
2431 if (pick->p_stat == SIDL || (pick->p_flag & P_ZOMBIE))
2434 vmsz = pgtok(vmspace_resident_count(pick->p_vmspace));
2441 ttyprintf(tp, " %s ", buf);
2443 ttyprintf(tp, "%ld.%02ldu ",
2444 utime.tv_sec, utime.tv_usec / 10000);
2445 ttyprintf(tp, "%ld.%02lds ",
2446 stime.tv_sec, stime.tv_usec / 10000);
2448 ttyprintf(tp, "?.??u ?.??s ");
2450 ttyprintf(tp, "%d%% %ldk\n", pctcpu / 100, vmsz);
2452 tp->t_rocount = 0; /* so pending input will be retyped if BS */
2456 * Returns 1 if p2 is "better" than p1
2458 * The algorithm for picking the "interesting" process is thus:
2460 * 1) Only foreground processes are eligible - implied.
2461 * 2) Runnable processes are favored over anything else. The runner
2462 * with the highest cpu utilization is picked (p_cpticks). Ties are
2463 * broken by picking the highest pid.
2464 * 3) The sleeper with the shortest sleep time is next. With ties,
2465 * we pick out just "short-term" sleepers (P_SINTR == 0).
2466 * 4) Further ties are broken by picking the highest pid.
2468 #define ISRUN(p) (((p)->p_stat == SRUN) || ((p)->p_stat == SIDL))
2469 #define TESTAB(a, b) ((a)<<1 | (b))
2475 proc_compare(p1, p2)
2476 struct proc *p1, *p2;
2482 * see if at least one of them is runnable
2484 switch (TESTAB(ISRUN(p1), ISRUN(p2))) {
2491 * tie - favor one with highest recent cpu utilization
2493 if (p2->p_cpticks > p1->p_cpticks)
2495 if (p1->p_cpticks > p2->p_cpticks)
2497 return (p2->p_pid > p1->p_pid); /* tie - return highest pid */
2502 switch (TESTAB((p1->p_flag & P_ZOMBIE), (p2->p_flag & P_ZOMBIE))) {
2508 return (p2->p_pid > p1->p_pid); /* tie - return highest pid */
2511 * pick the one with the smallest sleep time
2513 if (p2->p_slptime > p1->p_slptime)
2515 if (p1->p_slptime > p2->p_slptime)
2518 * favor one sleeping in a non-interruptible sleep
2520 if (p1->p_flag & P_SINTR && (p2->p_flag & P_SINTR) == 0)
2522 if (p2->p_flag & P_SINTR && (p1->p_flag & P_SINTR) == 0)
2524 return (p2->p_pid > p1->p_pid); /* tie - return highest pid */
2528 * Output char to tty; console putchar style.
2536 if (!ISSET(tp->t_state, TS_CONNECTED)) {
2541 (void)ttyoutput('\r', tp);
2542 (void)ttyoutput(c, tp);
2549 * Sleep on chan, returning ERESTART if tty changed while we napped and
2550 * returning any errors (e.g. EINTR/EWOULDBLOCK) reported by tsleep. If
2551 * the tty is revoked, restarting a pending call will redo validation done
2552 * at the start of the call.
2555 ttysleep(tp, chan, slpflags, wmesg, timo)
2565 error = tsleep(chan, slpflags, wmesg, timo);
2568 return (tp->t_gen == gen ? 0 : ERESTART);
2572 * Allocate a tty struct. Clists in the struct will be allocated by
2582 tp = kmalloc(sizeof *tp, M_TTYS, M_WAITOK|M_ZERO);
2589 * Free a tty struct. Clists in the struct should have been freed by
2592 * XXX not yet usable: since we support a half-closed state and do not
2593 * ref count the tty reference from the session, it is possible for a
2594 * session to hold a ref on the tty. See TTY_DO_FULL_CLOSE.
2608 SLIST_INSERT_HEAD(&tty_list, tp, t_list);
2612 sysctl_kern_ttys(SYSCTL_HANDLER_ARGS)
2616 SLIST_FOREACH(tp, &tty_list, t_list) {
2619 t.t_dev = (cdev_t)dev2udev(t.t_dev);
2620 error = SYSCTL_OUT(req, (caddr_t)&t, sizeof(t));
2627 SYSCTL_PROC(_kern, OID_AUTO, ttys, CTLTYPE_OPAQUE|CTLFLAG_RD,
2628 0, 0, sysctl_kern_ttys, "S,tty", "All struct ttys");
2640 ttyread(struct dev_read_args *ap)
2644 tp = ap->a_head.a_dev->si_tty;
2647 return ((*linesw[tp->t_line].l_read)(tp, ap->a_uio, ap->a_ioflag));
2651 ttywrite(struct dev_write_args *ap)
2655 tp = ap->a_head.a_dev->si_tty;
2658 return ((*linesw[tp->t_line].l_write)(tp, ap->a_uio, ap->a_ioflag));