freebsd-dev/sys/dev/nmdm/nmdm.c

644 lines
15 KiB
C

/*
* 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.
*
* $FreeBSD$
*/
/*
* Pseudo-nulmodem Driver
*/
#include "opt_compat.h"
#include <sys/param.h>
#include <sys/systm.h>
#if defined(COMPAT_43) || defined(COMPAT_SUNOS)
#include <sys/ioctl_compat.h>
#endif
#include <sys/proc.h>
#include <sys/tty.h>
#include <sys/conf.h>
#include <sys/fcntl.h>
#include <sys/poll.h>
#include <sys/kernel.h>
#include <sys/vnode.h>
#include <sys/signalvar.h>
#include <sys/malloc.h>
MALLOC_DEFINE(M_NLMDM, "nullmodem", "nullmodem data structures");
static void nmdmstart __P((struct tty *tp));
static void nmdmstop __P((struct tty *tp, int rw));
static void wakeup_other __P((struct tty *tp, int flag));
static void nmdminit __P((int n));
static d_open_t nmdmopen;
static d_close_t nmdmclose;
static d_read_t nmdmread;
static d_write_t nmdmwrite;
static d_ioctl_t nmdmioctl;
#define CDEV_MAJOR 18
static struct cdevsw nmdm_cdevsw = {
/* open */ nmdmopen,
/* close */ nmdmclose,
/* read */ nmdmread,
/* write */ nmdmwrite,
/* ioctl */ nmdmioctl,
/* poll */ ttypoll,
/* mmap */ nommap,
/* strategy */ nostrategy,
/* name */ "pts",
/* maj */ CDEV_MAJOR,
/* dump */ nodump,
/* psize */ nopsize,
/* flags */ D_TTY,
/* bmaj */ -1
};
#define BUFSIZ 100 /* Chunk size iomoved to/from user */
struct softpart {
struct tty nm_tty;
dev_t dev;
int modemsignals; /* bits defined in sys/ttycom.h */
int gotbreak;
};
struct nm_softc {
int pt_flags;
struct softpart part1, part2;
struct prison *pt_prison;
};
#define PF_STOPPED 0x10 /* user told stopped */
static void
nmdm_crossover(struct nm_softc *pti,
struct softpart *ourpart,
struct softpart *otherpart);
#define GETPARTS(tp, ourpart, otherpart) \
do { \
struct nm_softc *pti = tp->t_dev->si_drv1; \
if (tp == &pti->part1.nm_tty) { \
ourpart = &pti->part1; \
otherpart = &pti->part2; \
} else { \
ourpart = &pti->part2; \
otherpart = &pti->part1; \
} \
} while (0)
/*
* This function creates and initializes a pair of ttys.
*/
static void
nmdminit(n)
int n;
{
dev_t dev1, dev2;
struct nm_softc *pt;
/* For now we only map the lower 8 bits of the minor */
if (n & ~0xff)
return;
pt = malloc(sizeof(*pt), M_NLMDM, M_WAITOK);
bzero(pt, sizeof(*pt));
pt->part1.dev = dev1 = make_dev(&nmdm_cdevsw, n+n,
0, 0, 0666, "nmdm%dA", n);
pt->part2.dev = dev2 = make_dev(&nmdm_cdevsw, n+n+1,
0, 0, 0666, "nmdm%dB", n);
dev1->si_drv1 = dev2->si_drv1 = pt;
dev1->si_tty = &pt->part1.nm_tty;
dev2->si_tty = &pt->part2.nm_tty;
ttyregister(&pt->part1.nm_tty);
ttyregister(&pt->part2.nm_tty);
pt->part1.nm_tty.t_oproc = nmdmstart;
pt->part2.nm_tty.t_oproc = nmdmstart;
pt->part1.nm_tty.t_stop = nmdmstop;
pt->part2.nm_tty.t_dev = dev1;
pt->part1.nm_tty.t_dev = dev2;
pt->part2.nm_tty.t_stop = nmdmstop;
}
/*ARGSUSED*/
static int
nmdmopen(dev, flag, devtype, p)
dev_t dev;
int flag, devtype;
struct proc *p;
{
register struct tty *tp, *tp2;
int error;
int minr;
dev_t nextdev;
struct nm_softc *pti;
int is_b;
int pair;
struct softpart *ourpart, *otherpart;
/*
* XXX: Gross hack for DEVFS:
* If we openned this device, ensure we have the
* next one too, so people can open it.
*/
minr = dev2unit(dev);
pair = minr >> 1;
is_b = minr & 1;
if (pair < 127) {
nextdev = makedev(major(dev), (pair+pair) + 1);
if (!nextdev->si_drv1) {
nmdminit(pair + 1);
}
}
if (!dev->si_drv1)
nmdminit(pair);
if (!dev->si_drv1)
return(ENXIO);
pti = dev->si_drv1;
if (is_b)
tp = &pti->part2.nm_tty;
else
tp = &pti->part1.nm_tty;
GETPARTS(tp, ourpart, otherpart);
tp2 = &otherpart->nm_tty;
ourpart->modemsignals |= TIOCM_LE;
if ((tp->t_state & TS_ISOPEN) == 0) {
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;
} else if (tp->t_state & TS_XCLUDE && suser(p)) {
return (EBUSY);
} else if (pti->pt_prison != p->p_ucred->cr_prison) {
return (EBUSY);
}
/*
* If the other side is open we have carrier
*/
if (tp2->t_state & TS_ISOPEN) {
(void)(*linesw[tp->t_line].l_modem)(tp, 1);
}
/*
* And the other side gets carrier as we are now open.
*/
(void)(*linesw[tp2->t_line].l_modem)(tp2, 1);
/* External processing makes no sense here */
tp->t_lflag &= ~EXTPROC;
/*
* Wait here if we don't have carrier.
*/
#if 0
while ((tp->t_state & TS_CARR_ON) == 0) {
if (flag & FNONBLOCK)
break;
error = ttysleep(tp, TSA_CARR_ON(tp), TTIPRI | PCATCH,
"nmdopn", 0);
if (error)
return (error);
}
#endif
/*
* Give the line disciplin a chance to set this end up.
*/
error = (*linesw[tp->t_line].l_open)(dev, tp);
/*
* Wake up the other side.
* Theoretically not needed.
*/
ourpart->modemsignals |= TIOCM_DTR;
nmdm_crossover(pti, ourpart, otherpart);
if (error == 0)
wakeup_other(tp, FREAD|FWRITE); /* XXX */
return (error);
}
static int
nmdmclose(dev, flag, mode, p)
dev_t dev;
int flag, mode;
struct proc *p;
{
register struct tty *tp, *tp2;
int err;
struct softpart *ourpart, *otherpart;
/*
* let the other end know that the game is up
*/
tp = dev->si_tty;
GETPARTS(tp, ourpart, otherpart);
tp2 = &otherpart->nm_tty;
(void)(*linesw[tp2->t_line].l_modem)(tp2, 0);
/*
* XXX MDMBUF makes no sense for nmdms but would inhibit the above
* l_modem(). CLOCAL makes sense but isn't supported. Special
* l_modem()s that ignore carrier drop make no sense for nmdms but
* may be in use because other parts of the line discipline make
* sense for nmdms. Recover by doing everything that a normal
* ttymodem() would have done except for sending a SIGHUP.
*/
if (tp2->t_state & TS_ISOPEN) {
tp2->t_state &= ~(TS_CARR_ON | TS_CONNECTED);
tp2->t_state |= TS_ZOMBIE;
ttyflush(tp2, FREAD | FWRITE);
}
err = (*linesw[tp->t_line].l_close)(tp, flag);
ourpart->modemsignals &= ~TIOCM_DTR;
nmdm_crossover(dev->si_drv1, ourpart, otherpart);
nmdmstop(tp, FREAD|FWRITE);
(void) ttyclose(tp);
return (err);
}
static int
nmdmread(dev, uio, flag)
dev_t dev;
struct uio *uio;
int flag;
{
int error = 0;
struct tty *tp, *tp2;
struct softpart *ourpart, *otherpart;
tp = dev->si_tty;
GETPARTS(tp, ourpart, otherpart);
tp2 = &otherpart->nm_tty;
#if 0
if (tp2->t_state & TS_ISOPEN) {
error = (*linesw[tp->t_line].l_read)(tp, uio, flag);
wakeup_other(tp, FWRITE);
} else {
if (flag & IO_NDELAY) {
return (EWOULDBLOCK);
}
error = tsleep(TSA_PTC_READ(tp),
TTIPRI | PCATCH, "nmdout", 0);
}
}
#else
if ((error = (*linesw[tp->t_line].l_read)(tp, uio, flag)) == 0)
wakeup_other(tp, FWRITE);
#endif
return (error);
}
/*
* Write to pseudo-tty.
* Wakeups of controlling tty will happen
* indirectly, when tty driver calls nmdmstart.
*/
static int
nmdmwrite(dev, uio, flag)
dev_t dev;
struct uio *uio;
int flag;
{
register u_char *cp = 0;
register int cc = 0;
u_char locbuf[BUFSIZ];
int cnt = 0;
int error = 0;
struct tty *tp1, *tp;
struct softpart *ourpart, *otherpart;
tp1 = dev->si_tty;
/*
* Get the other tty struct.
* basically we are writing into the INPUT side of the other device.
*/
GETPARTS(tp1, ourpart, otherpart);
tp = &otherpart->nm_tty;
again:
if ((tp->t_state & TS_ISOPEN) == 0)
return (EIO);
while (uio->uio_resid > 0 || cc > 0) {
/*
* Fill up the buffer if it's empty
*/
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 ((tp->t_state & TS_ISOPEN) == 0) {
/* adjust for data copied in but not written */
uio->uio_resid += cc;
return (EIO);
}
}
while (cc > 0) {
if (((tp->t_rawq.c_cc + tp->t_canq.c_cc) >= (TTYHOG-2))
&& ((tp->t_canq.c_cc > 0) || !(tp->t_iflag&ICANON))) {
/*
* Come here to wait for space in outq,
* or space in rawq, or an empty canq.
*/
wakeup(TSA_HUP_OR_INPUT(tp));
if ((tp->t_state & TS_CONNECTED) == 0) {
/*
* Data piled up because not connected.
* Adjust for data copied in but
* not written.
*/
uio->uio_resid += cc;
return (EIO);
}
if (flag & IO_NDELAY) {
/*
* Don't wait if asked not to.
* Adjust for data copied in but
* not written.
*/
uio->uio_resid += cc;
if (cnt == 0)
return (EWOULDBLOCK);
return (0);
}
error = tsleep(TSA_PTC_WRITE(tp),
TTOPRI | PCATCH, "nmdout", 0);
if (error) {
/*
* Tsleep returned (signal?).
* Go find out what the user wants.
* adjust for data copied in but
* not written
*/
uio->uio_resid += cc;
return (error);
}
goto again;
}
(*linesw[tp->t_line].l_rint)(*cp++, tp);
cnt++;
cc--;
}
cc = 0;
}
return (0);
}
/*
* Start output on pseudo-tty.
* Wake up process selecting or sleeping for input from controlling tty.
*/
static void
nmdmstart(tp)
struct tty *tp;
{
register struct nm_softc *pti = tp->t_dev->si_drv1;
if (tp->t_state & TS_TTSTOP)
return;
pti->pt_flags &= ~PF_STOPPED;
wakeup_other(tp, FREAD);
}
/* Wakes up the OTHER tty;*/
static void
wakeup_other(tp, flag)
struct tty *tp;
int flag;
{
struct softpart *ourpart, *otherpart;
GETPARTS(tp, ourpart, otherpart);
if (flag & FREAD) {
selwakeup(&otherpart->nm_tty.t_rsel);
wakeup(TSA_PTC_READ((&otherpart->nm_tty)));
}
if (flag & FWRITE) {
selwakeup(&otherpart->nm_tty.t_wsel);
wakeup(TSA_PTC_WRITE((&otherpart->nm_tty)));
}
}
static void
nmdmstop(tp, flush)
register struct tty *tp;
int flush;
{
struct nm_softc *pti = tp->t_dev->si_drv1;
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;
/* change of perspective */
flag = 0;
if (flush & FREAD)
flag |= FWRITE;
if (flush & FWRITE)
flag |= FREAD;
wakeup_other(tp, flag);
}
#if 0
static int
nmdmpoll(dev_t dev, int events, struct proc *p)
{
register struct tty *tp = dev->si_tty;
register struct tty *tp2;
int revents = 0;
int s;
struct softpart *ourpart, *otherpart;
GETPARTS(tp, ourpart, otherpart);
tp2 = &otherpart->nm_tty;
if ((tp->t_state & TS_CONNECTED) == 0)
return (seltrue(dev, events, p) | POLLHUP);
/*
* Need to block timeouts (ttrstart).
*/
s = spltty();
/*
* First check if there is something to report immediatly.
*/
if ((events & (POLLIN | POLLRDNORM))) {
if (tp->t_iflag & ICANON) {
if (tp->t_canq.c_cc)
revents |= events & (POLLIN | POLLRDNORM);
} else {
if (tp->t_rawq.c_cc + tp->t_canq.c_cc)
revents |= events & (POLLIN | POLLRDNORM);
}
}
/*
* check if there is room in the other tty's input buffers.
*/
if ((events & (POLLOUT | POLLWRNORM))
&& ((tp2->t_rawq.c_cc + tp2->t_canq.c_cc < TTYHOG - 2)
|| (tp2->t_canq.c_cc == 0 && (tp2->t_iflag & ICANON)))) {
revents |= events & (POLLOUT | POLLWRNORM);
}
if (events & POLLHUP)
if ((tp->t_state & TS_CARR_ON) == 0)
revents |= POLLHUP;
/*
* If nothing immediate, set us to return when something IS found.
*/
if (revents == 0) {
if (events & (POLLIN | POLLRDNORM))
selrecord(p, &tp->t_rsel);
if (events & (POLLOUT | POLLWRNORM))
selrecord(p, &tp->t_wsel);
}
splx(s);
return (revents);
}
#endif /* 0 */
/*ARGSUSED*/
static int
nmdmioctl(dev, cmd, data, flag, p)
dev_t dev;
u_long cmd;
caddr_t data;
int flag;
struct proc *p;
{
register struct tty *tp = dev->si_tty;
struct nm_softc *pti = dev->si_drv1;
int error, s;
register struct tty *tp2;
struct softpart *ourpart, *otherpart;
s = spltty();
GETPARTS(tp, ourpart, otherpart);
tp2 = &otherpart->nm_tty;
error = (*linesw[tp->t_line].l_ioctl)(tp, cmd, data, flag, p);
if (error == ENOIOCTL)
error = ttioctl(tp, cmd, data, flag);
if (error == ENOIOCTL) {
switch (cmd) {
case TIOCSBRK:
otherpart->gotbreak = 1;
break;
case TIOCCBRK:
break;
case TIOCSDTR:
ourpart->modemsignals |= TIOCM_DTR;
break;
case TIOCCDTR:
ourpart->modemsignals &= TIOCM_DTR;
break;
case TIOCMSET:
ourpart->modemsignals = *(int *)data;
otherpart->modemsignals = *(int *)data;
break;
case TIOCMBIS:
ourpart->modemsignals |= *(int *)data;
break;
case TIOCMBIC:
ourpart->modemsignals &= ~(*(int *)data);
otherpart->modemsignals &= ~(*(int *)data);
break;
case TIOCMGET:
*(int *)data = ourpart->modemsignals;
break;
case TIOCMSDTRWAIT:
break;
case TIOCMGDTRWAIT:
*(int *)data = 0;
break;
case TIOCTIMESTAMP:
case TIOCDCDTIMESTAMP:
default:
splx(s);
error = ENOTTY;
return (error);
}
error = 0;
nmdm_crossover(pti, ourpart, otherpart);
}
splx(s);
return (error);
}
static void
nmdm_crossover(struct nm_softc *pti,
struct softpart *ourpart,
struct softpart *otherpart)
{
otherpart->modemsignals &= ~(TIOCM_CTS|TIOCM_CAR);
if (ourpart->modemsignals & TIOCM_RTS)
otherpart->modemsignals |= TIOCM_CTS;
if (ourpart->modemsignals & TIOCM_DTR)
otherpart->modemsignals |= TIOCM_CAR;
}
static void nmdm_drvinit __P((void *unused));
static void
nmdm_drvinit(unused)
void *unused;
{
cdevsw_add(&nmdm_cdevsw);
/* XXX: Gross hack for DEVFS */
nmdminit(0);
}
SYSINIT(nmdmdev,SI_SUB_DRIVERS,SI_ORDER_MIDDLE+CDEV_MAJOR,nmdm_drvinit,NULL)