/* $NetBSD: tty_pty.c,v 1.54 2000/11/21 03:53:27 enami Exp $ */ /* * Copyright (c) 1982, 1986, 1989, 1993 * 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_pty.c 8.4 (Berkeley) 2/20/95 */ /* * Pseudo-teletype Driver * (Actually two drivers, requiring two entries in 'cdevsw') */ #include "opt_compat_sunos.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #define DEFAULT_NPTYS 16 /* default number of initial ptys */ #define DEFAULT_MAXPTYS 256 /* default maximum number of ptys */ /* Macros to clear/set/test flags. */ #define SET(t, f) (t) |= (f) #define CLR(t, f) (t) &= ~((unsigned)(f)) #define ISSET(t, f) ((t) & (f)) #define BUFSIZ 100 /* Chunk size iomoved to/from user */ /* * pts == /dev/tty[pqrs]? * ptc == /dev/pty[pqrs]? */ struct pt_softc { struct tty *pt_tty; int pt_flags; struct selinfo pt_selr, pt_selw; u_char pt_send; u_char pt_ucntl; }; static struct pt_softc **pt_softc = NULL; /* pty array */ static int npty = 0; /* for pstat -t */ static int maxptys = DEFAULT_MAXPTYS; /* maximum number of ptys (sysctable) */ #if defined(MULTIPROCESSOR) || defined(LOCKDEBUG) static struct simplelock pt_softc_mutex = SIMPLELOCK_INITIALIZER; #endif #define PF_PKT 0x08 /* packet mode */ #define PF_STOPPED 0x10 /* user told stopped */ #define PF_REMOTE 0x20 /* remote and flow controlled input */ #define PF_NOSTOP 0x40 #define PF_UCNTL 0x80 /* user control mode */ void ptyattach __P((int)); void ptcwakeup __P((struct tty *, int)); int ptcopen __P((dev_t, int, int, struct proc *)); struct tty *ptytty __P((dev_t)); void ptsstart __P((struct tty *)); int pty_maxptys __P((int, int)); static struct pt_softc **ptyarralloc __P((int)); static int check_pty __P((dev_t)); /* * Allocate and zero array of nelem elements. */ static struct pt_softc ** ptyarralloc(nelem) int nelem; { struct pt_softc **pt; nelem += 10; pt = malloc(nelem * sizeof(struct pt_softc *), M_DEVBUF, M_WAITOK); memset(pt, '\0', nelem * sizeof(struct pt_softc *)); return pt; } /* * Check if the minor is correct and ensure necessary structures * are properly allocated. */ static int check_pty(dev) dev_t dev; { struct pt_softc *pti; if (minor(dev) >= npty) { struct pt_softc **newpt; int newnpty; /* check if the requested pty can be granted */ if (minor(dev) >= maxptys) { limit_reached: tablefull("pty", "increase kern.maxptys"); return (ENXIO); } /* * Now grab the pty array mutex - we need to ensure * that the pty array is consistent while copying it's * content to newly allocated, larger space; we also * need to be safe against pty_maxptys(). */ simple_lock(&pt_softc_mutex); do { for(newnpty = npty; newnpty <= minor(dev); newnpty *= 2); if (newnpty > maxptys) newnpty = maxptys; simple_unlock(&pt_softc_mutex); newpt = ptyarralloc(newnpty); simple_lock(&pt_softc_mutex); if (maxptys == npty) { simple_unlock(&pt_softc_mutex); goto limit_reached; } } while(newnpty > maxptys); /* * If the pty array was not enlarged while we were waiting * for mutex, copy current contents of pt_softc[] to newly * allocated array and start using the new bigger array. */ if (minor(dev) >= npty) { memcpy(newpt, pt_softc, npty*sizeof(struct pt_softc *)); free(pt_softc, M_DEVBUF); pt_softc = newpt; npty = newnpty; } else { /* was enlarged when waited fot lock, free new space */ free(newpt, M_DEVBUF); } simple_unlock(&pt_softc_mutex); } /* * If the entry is not yet allocated, allocate one. The mutex is * needed so that the state of pt_softc[] array is consistant * in case it has been longened above. */ if (!pt_softc[minor(dev)]) { MALLOC(pti, struct pt_softc *, sizeof(struct pt_softc), M_DEVBUF, M_WAITOK); pti->pt_tty = ttymalloc(); simple_lock(&pt_softc_mutex); /* * Check the entry again - it might have been * added while we were waiting for mutex. */ if (!pt_softc[minor(dev)]) { tty_attach(pti->pt_tty); pt_softc[minor(dev)] = pti; } else { ttyfree(pti->pt_tty); FREE(pti, M_DEVBUF); } simple_unlock(&pt_softc_mutex); } return (0); } /* * Set maxpty in thread-safe way. Returns 0 in case of error, otherwise * new value of maxptys. */ int pty_maxptys(newmax, set) int newmax, set; { if (!set) return (maxptys); /* the value cannot be set to value lower than current number of ptys */ if (newmax < npty) return (0); /* can proceed immediatelly if bigger than current maximum */ if (newmax > maxptys) { maxptys = newmax; return (maxptys); } /* * We have to grab the pt_softc lock, so that we would pick correct * value of npty (might be modified in check_pty()). */ simple_lock(&pt_softc_mutex); if (newmax > npty) maxptys = newmax; simple_unlock(&pt_softc_mutex); return (maxptys); } /* * Establish n (or default if n is 1) ptys in the system. */ void ptyattach(n) int n; { /* maybe should allow 0 => none? */ if (n <= 1) n = DEFAULT_NPTYS; pt_softc = ptyarralloc(n); npty = n; } /*ARGSUSED*/ int ptsopen(dev, flag, devtype, p) dev_t dev; int flag, devtype; struct proc *p; { struct pt_softc *pti; struct tty *tp; int error; if ((error = check_pty(dev))) return (error); pti = pt_softc[minor(dev)]; tp = pti->pt_tty; if (!ISSET(tp->t_state, TS_ISOPEN)) { ttychars(tp); /* Set up default chars */ tp->t_iflag = TTYDEF_IFLAG; tp->t_oflag = TTYDEF_OFLAG; tp->t_lflag = TTYDEF_LFLAG; tp->t_cflag = TTYDEF_CFLAG; tp->t_ispeed = tp->t_ospeed = TTYDEF_SPEED; ttsetwater(tp); /* would be done in xxparam() */ } else if (ISSET(tp->t_state, TS_XCLUDE) && p->p_ucred->cr_uid != 0) return (EBUSY); if (tp->t_oproc) /* Ctrlr still around. */ SET(tp->t_state, TS_CARR_ON); if (!ISSET(flag, O_NONBLOCK)) while (!ISSET(tp->t_state, TS_CARR_ON)) { tp->t_wopen++; error = ttysleep(tp, &tp->t_rawq, TTIPRI | PCATCH, ttopen, 0); tp->t_wopen--; if (error) return (error); } error = (*tp->t_linesw->l_open)(dev, tp); ptcwakeup(tp, FREAD|FWRITE); return (error); } int ptsclose(dev, flag, mode, p) dev_t dev; int flag, mode; struct proc *p; { struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; int error; error = (*tp->t_linesw->l_close)(tp, flag); error |= ttyclose(tp); ptcwakeup(tp, FREAD|FWRITE); return (error); } int ptsread(dev, uio, flag) dev_t dev; struct uio *uio; int flag; { struct proc *p = curproc; struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; int error = 0; again: if (pti->pt_flags & PF_REMOTE) { while (isbackground(p, tp)) { if (sigismasked(p, SIGTTIN) || p->p_pgrp->pg_jobc == 0 || p->p_flag & P_PPWAIT) return (EIO); pgsignal(p->p_pgrp, SIGTTIN, 1); error = ttysleep(tp, (caddr_t)&lbolt, TTIPRI | PCATCH, ttybg, 0); if (error) return (error); } if (tp->t_canq.c_cc == 0) { if (flag & IO_NDELAY) return (EWOULDBLOCK); error = ttysleep(tp, (caddr_t)&tp->t_canq, TTIPRI | PCATCH, ttyin, 0); if (error) return (error); goto again; } while (tp->t_canq.c_cc > 1 && uio->uio_resid > 0) if (ureadc(getc(&tp->t_canq), uio) < 0) { error = EFAULT; break; } if (tp->t_canq.c_cc == 1) (void) getc(&tp->t_canq); if (tp->t_canq.c_cc) return (error); } else if (tp->t_oproc) error = (*tp->t_linesw->l_read)(tp, uio, flag); ptcwakeup(tp, FWRITE); return (error); } /* * Write to pseudo-tty. * Wakeups of controlling tty will happen * indirectly, when tty driver calls ptsstart. */ int ptswrite(dev, uio, flag) dev_t dev; struct uio *uio; int flag; { struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; if (tp->t_oproc == 0) return (EIO); return ((*tp->t_linesw->l_write)(tp, uio, flag)); } /* * Start output on pseudo-tty. * Wake up process polling or sleeping for input from controlling tty. */ void ptsstart(tp) struct tty *tp; { struct pt_softc *pti = pt_softc[minor(tp->t_dev)]; if (ISSET(tp->t_state, TS_TTSTOP)) return; if (pti->pt_flags & PF_STOPPED) { pti->pt_flags &= ~PF_STOPPED; pti->pt_send = TIOCPKT_START; } ptcwakeup(tp, FREAD); } void ptsstop(tp, flush) struct tty *tp; int flush; { struct pt_softc *pti = pt_softc[minor(tp->t_dev)]; int flag; /* note: FLUSHREAD and FLUSHWRITE already ok */ if (flush == 0) { flush = TIOCPKT_STOP; pti->pt_flags |= PF_STOPPED; } else pti->pt_flags &= ~PF_STOPPED; pti->pt_send |= flush; /* change of perspective */ flag = 0; if (flush & FREAD) flag |= FWRITE; if (flush & FWRITE) flag |= FREAD; ptcwakeup(tp, flag); } void ptcwakeup(tp, flag) struct tty *tp; int flag; { struct pt_softc *pti = pt_softc[minor(tp->t_dev)]; if (flag & FREAD) { selwakeup(&pti->pt_selr); wakeup((caddr_t)&tp->t_outq.c_cf); } if (flag & FWRITE) { selwakeup(&pti->pt_selw); wakeup((caddr_t)&tp->t_rawq.c_cf); } } /*ARGSUSED*/ int ptcopen(dev, flag, devtype, p) dev_t dev; int flag, devtype; struct proc *p; { struct pt_softc *pti; struct tty *tp; int error; if ((error = check_pty(dev))) return (error); pti = pt_softc[minor(dev)]; tp = pti->pt_tty; if (tp->t_oproc) return (EIO); tp->t_oproc = ptsstart; (void)(*tp->t_linesw->l_modem)(tp, 1); CLR(tp->t_lflag, EXTPROC); pti->pt_flags = 0; pti->pt_send = 0; pti->pt_ucntl = 0; return (0); } /*ARGSUSED*/ int ptcclose(dev, flag, devtype, p) dev_t dev; int flag, devtype; struct proc *p; { struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; (void)(*tp->t_linesw->l_modem)(tp, 0); CLR(tp->t_state, TS_CARR_ON); tp->t_oproc = 0; /* mark closed */ return (0); } int ptcread(dev, uio, flag) dev_t dev; struct uio *uio; int flag; { struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; char buf[BUFSIZ]; int error = 0, cc; /* * We want to block until the slave * is open, and there's something to read; * but if we lost the slave or we're NBIO, * then return the appropriate error instead. */ for (;;) { if (ISSET(tp->t_state, TS_ISOPEN)) { if (pti->pt_flags&PF_PKT && pti->pt_send) { error = ureadc((int)pti->pt_send, uio); if (error) return (error); if (pti->pt_send & TIOCPKT_IOCTL) { cc = min(uio->uio_resid, sizeof(tp->t_termios)); uiomove((caddr_t) &tp->t_termios, cc, uio); } pti->pt_send = 0; return (0); } if (pti->pt_flags&PF_UCNTL && pti->pt_ucntl) { error = ureadc((int)pti->pt_ucntl, uio); if (error) return (error); pti->pt_ucntl = 0; return (0); } if (tp->t_outq.c_cc && !ISSET(tp->t_state, TS_TTSTOP)) break; } if (!ISSET(tp->t_state, TS_CARR_ON)) return (0); /* EOF */ if (flag & IO_NDELAY) return (EWOULDBLOCK); error = tsleep((caddr_t)&tp->t_outq.c_cf, TTIPRI | PCATCH, ttyin, 0); if (error) return (error); } if (pti->pt_flags & (PF_PKT|PF_UCNTL)) error = ureadc(0, uio); while (uio->uio_resid > 0 && error == 0) { cc = q_to_b(&tp->t_outq, buf, min(uio->uio_resid, BUFSIZ)); if (cc <= 0) break; error = uiomove(buf, cc, uio); } if (tp->t_outq.c_cc <= tp->t_lowat) { if (ISSET(tp->t_state, TS_ASLEEP)) { CLR(tp->t_state, TS_ASLEEP); wakeup((caddr_t)&tp->t_outq); } selwakeup(&tp->t_wsel); } return (error); } int ptcwrite(dev, uio, flag) dev_t dev; struct uio *uio; int flag; { struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; u_char *cp = NULL; int cc = 0; u_char locbuf[BUFSIZ]; int cnt = 0; int error = 0; again: if (!ISSET(tp->t_state, TS_ISOPEN)) goto block; if (pti->pt_flags & PF_REMOTE) { if (tp->t_canq.c_cc) goto block; while (uio->uio_resid > 0 && tp->t_canq.c_cc < TTYHOG - 1) { if (cc == 0) { cc = min(uio->uio_resid, BUFSIZ); cc = min(cc, TTYHOG - 1 - tp->t_canq.c_cc); cp = locbuf; error = uiomove((caddr_t)cp, cc, uio); if (error) return (error); /* check again for safety */ if (!ISSET(tp->t_state, TS_ISOPEN)) return (EIO); } if (cc) (void) b_to_q((char *)cp, cc, &tp->t_canq); cc = 0; } (void) putc(0, &tp->t_canq); ttwakeup(tp); wakeup((caddr_t)&tp->t_canq); return (0); } while (uio->uio_resid > 0) { if (cc == 0) { cc = min(uio->uio_resid, BUFSIZ); cp = locbuf; error = uiomove((caddr_t)cp, cc, uio); if (error) return (error); /* check again for safety */ if (!ISSET(tp->t_state, TS_ISOPEN)) return (EIO); } while (cc > 0) { if ((tp->t_rawq.c_cc + tp->t_canq.c_cc) >= TTYHOG - 2 && (tp->t_canq.c_cc > 0 || !ISSET(tp->t_iflag, ICANON))) { wakeup((caddr_t)&tp->t_rawq); goto block; } (*tp->t_linesw->l_rint)(*cp++, tp); cnt++; cc--; } cc = 0; } return (0); block: /* * Come here to wait for slave to open, for space * in outq, or space in rawq. */ if (!ISSET(tp->t_state, TS_CARR_ON)) return (EIO); if (flag & IO_NDELAY) { /* adjust for data copied in but not written */ uio->uio_resid += cc; if (cnt == 0) return (EWOULDBLOCK); return (0); } error = tsleep((caddr_t)&tp->t_rawq.c_cf, TTOPRI | PCATCH, ttyout, 0); if (error) { /* adjust for data copied in but not written */ uio->uio_resid += cc; return (error); } goto again; } int ptcpoll(dev, events, p) dev_t dev; int events; struct proc *p; { struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; int revents = 0; int s = splsoftclock(); if (events & (POLLIN | POLLRDNORM)) if (ISSET(tp->t_state, TS_ISOPEN) && ((tp->t_outq.c_cc > 0 && !ISSET(tp->t_state, TS_TTSTOP)) || ((pti->pt_flags & PF_PKT) && pti->pt_send) || ((pti->pt_flags & PF_UCNTL) && pti->pt_ucntl))) revents |= events & (POLLIN | POLLRDNORM); if (events & (POLLOUT | POLLWRNORM)) if (ISSET(tp->t_state, TS_ISOPEN) && ((pti->pt_flags & PF_REMOTE) ? (tp->t_canq.c_cc == 0) : ((tp->t_rawq.c_cc + tp->t_canq.c_cc < TTYHOG-2) || (tp->t_canq.c_cc == 0 && ISSET(tp->t_iflag, ICANON))))) revents |= events & (POLLOUT | POLLWRNORM); if (events & POLLHUP) if (!ISSET(tp->t_state, TS_CARR_ON)) revents |= POLLHUP; if (revents == 0) { if (events & (POLLIN | POLLHUP | POLLRDNORM)) selrecord(p, &pti->pt_selr); if (events & (POLLOUT | POLLWRNORM)) selrecord(p, &pti->pt_selw); } splx(s); return (revents); } struct tty * ptytty(dev) dev_t dev; { struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; return (tp); } /*ARGSUSED*/ int ptyioctl(dev, cmd, data, flag, p) dev_t dev; u_long cmd; caddr_t data; int flag; struct proc *p; { struct pt_softc *pti = pt_softc[minor(dev)]; struct tty *tp = pti->pt_tty; u_char *cc = tp->t_cc; int stop, error, sig; /* * IF CONTROLLER STTY THEN MUST FLUSH TO PREVENT A HANG. * ttywflush(tp) will hang if there are characters in the outq. */ if (cmd == TIOCEXT) { /* * When the EXTPROC bit is being toggled, we need * to send an TIOCPKT_IOCTL if the packet driver * is turned on. */ if (*(int *)data) { if (pti->pt_flags & PF_PKT) { pti->pt_send |= TIOCPKT_IOCTL; ptcwakeup(tp, FREAD); } SET(tp->t_lflag, EXTPROC); } else { if (ISSET(tp->t_lflag, EXTPROC) && (pti->pt_flags & PF_PKT)) { pti->pt_send |= TIOCPKT_IOCTL; ptcwakeup(tp, FREAD); } CLR(tp->t_lflag, EXTPROC); } return(0); } else if (cdevsw[major(dev)].d_open == ptcopen) switch (cmd) { case TIOCGPGRP: #ifdef COMPAT_SUNOS { /* * I'm not sure about SunOS TIOCGPGRP semantics * on PTYs, but it's something like this: */ extern struct emul emul_sunos; if (p->p_emul == &emul_sunos && tp->t_pgrp == 0) return (EIO); *(int *)data = tp->t_pgrp->pg_id; return (0); } #endif /* * We avoid calling ttioctl on the controller since, * in that case, tp must be the controlling terminal. */ *(int *)data = tp->t_pgrp ? tp->t_pgrp->pg_id : 0; return (0); case TIOCPKT: if (*(int *)data) { if (pti->pt_flags & PF_UCNTL) return (EINVAL); pti->pt_flags |= PF_PKT; } else pti->pt_flags &= ~PF_PKT; return (0); case TIOCUCNTL: if (*(int *)data) { if (pti->pt_flags & PF_PKT) return (EINVAL); pti->pt_flags |= PF_UCNTL; } else pti->pt_flags &= ~PF_UCNTL; return (0); case TIOCREMOTE: if (*(int *)data) pti->pt_flags |= PF_REMOTE; else pti->pt_flags &= ~PF_REMOTE; ttyflush(tp, FREAD|FWRITE); return (0); #ifdef COMPAT_OLDTTY case TIOCSETP: case TIOCSETN: #endif case TIOCSETD: case TIOCSETA: case TIOCSETAW: case TIOCSETAF: ndflush(&tp->t_outq, tp->t_outq.c_cc); break; case TIOCSIG: sig = (int)(long)*(caddr_t *)data; if (sig <= 0 || sig >= NSIG) return (EINVAL); if (!ISSET(tp->t_lflag, NOFLSH)) ttyflush(tp, FREAD|FWRITE); pgsignal(tp->t_pgrp, sig, 1); if ((sig == SIGINFO) && (!ISSET(tp->t_lflag, NOKERNINFO))) ttyinfo(tp); return(0); } error = (*tp->t_linesw->l_ioctl)(tp, cmd, data, flag, p); if (error < 0) error = ttioctl(tp, cmd, data, flag, p); if (error < 0) { if (pti->pt_flags & PF_UCNTL && (cmd & ~0xff) == UIOCCMD(0)) { if (cmd & 0xff) { pti->pt_ucntl = (u_char)cmd; ptcwakeup(tp, FREAD); } return (0); } error = ENOTTY; } /* * If external processing and packet mode send ioctl packet. */ if (ISSET(tp->t_lflag, EXTPROC) && (pti->pt_flags & PF_PKT)) { switch(cmd) { case TIOCSETA: case TIOCSETAW: case TIOCSETAF: #ifdef COMPAT_OLDTTY case TIOCSETP: case TIOCSETN: case TIOCSETC: case TIOCSLTC: case TIOCLBIS: case TIOCLBIC: case TIOCLSET: #endif pti->pt_send |= TIOCPKT_IOCTL; ptcwakeup(tp, FREAD); default: break; } } stop = ISSET(tp->t_iflag, IXON) && CCEQ(cc[VSTOP], CTRL('s')) && CCEQ(cc[VSTART], CTRL('q')); if (pti->pt_flags & PF_NOSTOP) { if (stop) { pti->pt_send &= ~TIOCPKT_NOSTOP; pti->pt_send |= TIOCPKT_DOSTOP; pti->pt_flags &= ~PF_NOSTOP; ptcwakeup(tp, FREAD); } } else { if (!stop) { pti->pt_send &= ~TIOCPKT_DOSTOP; pti->pt_send |= TIOCPKT_NOSTOP; pti->pt_flags |= PF_NOSTOP; ptcwakeup(tp, FREAD); } } return (error); }