/*
* Copyright (c) 2006-2023, RT-Thread Development Team
*
* SPDX-License-Identifier: Apache-2.0
*
* Change Logs:
* Date Author Notes
* 2023-12-07 Shell init ver.
*/
#include <ipc/condvar.h>
#include <rid_bitmap.h>
#include <terminal/terminal.h>
#include <terminal/tty_internal.h>
#include <ptyfs.h>
#include <rtthread.h>
/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2008 Ed Schouten <ed@FreeBSD.org>
* All rights reserved.
*
* Portions of this software were developed under sponsorship from Snow
* B.V., the Netherlands.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.
*/
#define PTS_EXTERNAL
/*
* Per-PTS structure.
*
* List of locks
* (t) locked by tty_lock()
* (c) const until freeing
*/
struct pts_softc
{
int pts_unit; /* (c) Device unit number. */
unsigned int pts_flags; /* (t) Device flags. */
#define PTS_PKT 0x1 /* Packet mode. */
#define PTS_FINISHED 0x2 /* Return errors on read()/write(). */
#define PTS_PTLOCKED 0x4 /* ioctl %TIOCSPTLCK/%TIOCGPTLCK */
char pts_pkt; /* (t) Unread packet mode data. */
struct rt_condvar pts_inwait; /* (t) Blocking write() on master. */
struct rt_wqueue pts_inpoll; /* (t) Select queue for write(). */
struct rt_condvar pts_outwait; /* (t) Blocking read() on master. */
struct rt_wqueue pts_outpoll; /* (t) Select queue for read(). */
struct ucred *pts_cred; /* (c) Resource limit. */
rt_device_t pts_master; /** (c) Master device.
* (Note: in rtsmart kernel, we support
* multi-instance ptmx )
*/
};
/**
* Controller-side file operations.
* (P)seudo-(T)erminal (M)ultiple(X)er
*/
static int ptsdev_read(struct lwp_tty *tp, struct uio *uio,
struct ucred *active_cred, int oflags,
struct rt_thread *td)
{
struct pts_softc *psc = tty_softc(tp);
int error = 0;
char pkt;
if (uio->uio_resid == 0)
return (0);
tty_lock(tp);
for (;;)
{
/*
* Implement packet mode. When packet mode is turned on,
* the first byte contains a bitmask of events that
* occurred (start, stop, flush, window size, etc).
*/
if (psc->pts_flags & PTS_PKT && psc->pts_pkt)
{
pkt = psc->pts_pkt;
psc->pts_pkt = 0;
tty_unlock(tp);
error = uiomove(&pkt, 1, uio);
return (error);
}
/*
* Transmit regular data.
*
* XXX: We shouldn't use ttydisc_getc_poll()! Even
* though in this implementation, there is likely going
* to be data, we should just call ttydisc_getc_uio()
* and use its return value to sleep.
*/
if (ttydisc_getc_poll(tp))
{
if (psc->pts_flags & PTS_PKT)
{
/*
* XXX: Small race. Fortunately PTY
* consumers aren't multithreaded.
*/
tty_unlock(tp);
pkt = TIOCPKT_DATA;
error = uiomove(&pkt, 1, uio);
if (error)
return (error);
tty_lock(tp);
}
error = ttydisc_getc_uio(tp, uio);
break;
}
/* Maybe the device isn't used anyway. */
if (psc->pts_flags & PTS_FINISHED)
break;
/* Wait for more data. */
if (oflags & O_NONBLOCK)
{
error = EWOULDBLOCK;
break;
}
error = cv_wait_sig(&psc->pts_outwait, tp->t_mtx);
if (error != 0)
break;
}
tty_unlock(tp);
return (error);
}
static int ptsdev_write(struct lwp_tty *tp, struct uio *uio,
struct ucred *active_cred, int oflags,
struct rt_thread *td)
{
struct pts_softc *psc = tty_softc(tp);
char ib[256], *ibstart;
size_t iblen, rintlen;
int error = 0;
if (uio->uio_resid == 0)
return (0);
for (;;)
{
ibstart = ib;
iblen = MIN(uio->uio_resid, sizeof ib);
error = uiomove(ib, iblen, uio);
tty_lock(tp);
if (error != 0)
{
iblen = 0;
goto done;
}
/*
* When possible, avoid the slow path. rint_bypass()
* copies all input to the input queue at once.
*/
MPASS(iblen > 0);
do
{
rintlen = ttydisc_rint_simple(tp, ibstart, iblen);
ibstart += rintlen;
iblen -= rintlen;
if (iblen == 0)
{
/* All data written. */
break;
}
/* Maybe the device isn't used anyway. */
if (psc->pts_flags & PTS_FINISHED)
{
error = -EIO;
goto done;
}
/* Wait for more data. */
if (oflags & O_NONBLOCK)
{
error = -EWOULDBLOCK;
goto done;
}
/* Wake up users on the slave side. */
ttydisc_rint_done(tp);
error = cv_wait_sig(&psc->pts_inwait, tp->t_mtx);
if (error != 0)
goto done;
} while (iblen > 0);
if (uio->uio_resid == 0)
break;
tty_unlock(tp);
}
done:
ttydisc_rint_done(tp);
tty_unlock(tp);
/*
* Don't account for the part of the buffer that we couldn't
* pass to the TTY.
*/
uio->uio_resid += iblen;
return (error);
}
static int ptsdev_ioctl(struct lwp_tty *tp, rt_ubase_t cmd, void *data,
struct ucred *active_cred, int fflags,
struct rt_thread *td)
{
struct pts_softc *psc = tty_softc(tp);
int error = 0, sig;
switch (cmd)
{
#ifdef USING_BSD_IOCTL_EXT
case FIODTYPE:
*(int *)data = D_TTY;
return (0);
#endif
case FIONBIO:
/* This device supports non-blocking operation. */
return (0);
case FIONREAD:
tty_lock(tp);
if (psc->pts_flags & PTS_FINISHED)
{
/* Force read() to be called. */
*(int *)data = 1;
}
else
{
*(int *)data = ttydisc_getc_poll(tp);
}
tty_unlock(tp);
return (0);
#ifdef USING_BSD_IOCTL_EXT
case FIODGNAME:
#ifdef COMPAT_FREEBSD32
case FIODGNAME_32:
#endif
{
struct fiodgname_arg *fgn;
const char *p;
int i;
/* Reverse device name lookups, for ptsname() and ttyname(). */
fgn = data;
p = tty_devname(tp);
i = strlen(p) + 1;
if (i > fgn->len)
return -EINVAL;
return (copyout(p, fiodgname_buf_get_ptr(fgn, cmd), i));
}
#endif
/*
* We need to implement TIOCGPGRP and TIOCGSID here again. When
* called on the pseudo-terminal master, it should not check if
* the terminal is the foreground terminal of the calling
* process.
*
* TIOCGETA is also implemented here. Various Linux PTY routines
* often call isatty(), which is implemented by tcgetattr().
*/
case TIOCGETA:
/* Obtain terminal flags through tcgetattr(). */
tty_lock(tp);
*(struct termios *)data = tp->t_termios;
tty_unlock(tp);
return (0);
case TIOCSETAF:
case TIOCSETAW:
/*
* We must make sure we turn tcsetattr() calls of TCSAFLUSH and
* TCSADRAIN into something different. If an application would
* call TCSAFLUSH or TCSADRAIN on the master descriptor, it may
* deadlock waiting for all data to be read.
*/
cmd = TIOCSETA;
break;
case TIOCGPTN:
/*
* Get the device unit number.
*/
if (psc->pts_unit < 0)
return -ENOTTY;
*(unsigned int *)data = psc->pts_unit;
return (0);
case TIOCGPGRP:
/* Get the foreground process group ID. */
tty_lock(tp);
if (tp->t_pgrp != NULL)
*(int *)data = tp->t_pgrp->pgid;
else
*(int *)data = NO_PID;
tty_unlock(tp);
return (0);
case TIOCGSID:
/* Get the session leader process ID. */
tty_lock(tp);
if (tp->t_session == NULL)
error = -ENOTTY;
else
*(int *)data = tp->t_session->sid;
tty_unlock(tp);
return (error);
#ifdef USING_BSD_IOCTL_EXT
case TIOCPTMASTER:
/* Yes, we are a pseudo-terminal master. */
return (0);
#endif /* USING_BSD_IOCTL_EXT */
case TIOCSIG:
/* Signal the foreground process group. */
sig = *(int *)data;
if (sig < 1 || sig >= _LWP_NSIG)
return -EINVAL;
tty_lock(tp);
lwp_tty_signal_pgrp(tp, sig);
tty_unlock(tp);
return (0);
case TIOCPKT:
/* Enable/disable packet mode. */
tty_lock(tp);
if (*(int *)data)
psc->pts_flags |= PTS_PKT;
else
psc->pts_flags &= ~PTS_PKT;
tty_unlock(tp);
return (0);
}
/* Just redirect this ioctl to the slave device. */
tty_lock(tp);
error = tty_ioctl(tp, cmd, data, fflags, td);
tty_unlock(tp);
if (error == -ENOIOCTL)
error = -ENOTTY;
return error;
}
static int ptsdev_poll(struct lwp_tty *tp, struct rt_pollreq *req,
struct ucred *active_cred, struct rt_thread *td)
{
struct pts_softc *psc = tty_softc(tp);
int revents = 0;
int events = req->_key;
tty_lock(tp);
if (psc->pts_flags & PTS_FINISHED)
{
/* Slave device is not opened. */
tty_unlock(tp);
return ((events & (POLLIN | POLLRDNORM)) | POLLHUP);
}
if (events & (POLLIN | POLLRDNORM))
{
/* See if we can getc something. */
if (ttydisc_getc_poll(tp) || (psc->pts_flags & PTS_PKT && psc->pts_pkt))
revents |= events & (POLLIN | POLLRDNORM);
}
if (events & (POLLOUT | POLLWRNORM))
{
/* See if we can rint something. */
if (ttydisc_rint_poll(tp))
revents |= events & (POLLOUT | POLLWRNORM);
}
/*
* No need to check for POLLHUP here. This device cannot be used
* as a callout device, which means we always have a carrier,
* because the master is.
*/
if (revents == 0)
{
/*
* This code might look misleading, but the naming of
* poll events on this side is the opposite of the slave
* device.
*/
if (events & (POLLIN | POLLRDNORM))
rt_poll_add(&psc->pts_outpoll, req);
if (events & (POLLOUT | POLLWRNORM))
rt_poll_add(&psc->pts_inpoll, req);
}
tty_unlock(tp);
return (revents);
}
#if USING_BSD_KQUEUE
/*
* kqueue support.
*/
static void pts_kqops_read_detach(struct knote *kn)
{
struct file *fp = kn->kn_fp;
struct lwp_tty *tp = fp->f_data;
struct pts_softc *psc = tty_softc(tp);
knlist_remove(&psc->pts_outpoll.si_note, kn, 0);
}
static int pts_kqops_read_event(struct knote *kn, long hint)
{
struct file *fp = kn->kn_fp;
struct lwp_tty *tp = fp->f_data;
struct pts_softc *psc = tty_softc(tp);
if (psc->pts_flags & PTS_FINISHED)
{
kn->kn_flags |= EV_EOF;
return (1);
}
else
{
kn->kn_data = ttydisc_getc_poll(tp);
return (kn->kn_data > 0);
}
}
static void pts_kqops_write_detach(struct knote *kn)
{
struct file *fp = kn->kn_fp;
struct lwp_tty *tp = fp->f_data;
struct pts_softc *psc = tty_softc(tp);
knlist_remove(&psc->pts_inpoll.si_note, kn, 0);
}
static int pts_kqops_write_event(struct knote *kn, long hint)
{
struct file *fp = kn->kn_fp;
struct lwp_tty *tp = fp->f_data;
struct pts_softc *psc = tty_softc(tp);
if (psc->pts_flags & PTS_FINISHED)
{
kn->kn_flags |= EV_EOF;
return (1);
}
else
{
kn->kn_data = ttydisc_rint_poll(tp);
return (kn->kn_data > 0);
}
}
static struct filterops pts_kqops_read = {
.f_isfd = 1,
.f_detach = pts_kqops_read_detach,
.f_event = pts_kqops_read_event,
};
static struct filterops pts_kqops_write = {
.f_isfd = 1,
.f_detach = pts_kqops_write_detach,
.f_event = pts_kqops_write_event,
};
static int ptsdev_kqfilter(struct file *fp, struct knote *kn)
{
struct lwp_tty *tp = fp->f_data;
struct pts_softc *psc = tty_softc(tp);
int error = 0;
tty_lock(tp);
switch (kn->kn_filter)
{
case EVFILT_READ:
kn->kn_fop = &pts_kqops_read;
knlist_add(&psc->pts_outpoll.si_note, kn, 1);
break;
case EVFILT_WRITE:
kn->kn_fop = &pts_kqops_write;
knlist_add(&psc->pts_inpoll.si_note, kn, 1);
break;
default:
error = EINVAL;
break;
}
tty_unlock(tp);
return (error);
}
#endif
#if USING_BSD_STAT
static int ptsdev_stat(struct file *fp, struct stat *sb,
struct ucred *active_cred)
{
struct lwp_tty *tp = fp->f_data;
#ifdef PTS_EXTERNAL
struct pts_softc *psc = tty_softc(tp);
#endif /* PTS_EXTERNAL */
struct cdev *dev = tp->t_dev;
/*
* According to POSIX, we must implement an fstat(). This also
* makes this implementation compatible with Linux binaries,
* because Linux calls fstat() on the pseudo-terminal master to
* obtain st_rdev.
*
* XXX: POSIX also mentions we must fill in st_dev, but how?
*/
bzero(sb, sizeof *sb);
#ifdef PTS_EXTERNAL
if (psc->pts_cdev != NULL)
sb->st_ino = sb->st_rdev = dev2udev(psc->pts_cdev);
else
#endif /* PTS_EXTERNAL */
sb->st_ino = sb->st_rdev = tty_udev(tp);
sb->st_atim = dev->si_atime;
sb->st_ctim = dev->si_ctime;
sb->st_mtim = dev->si_mtime;
sb->st_uid = dev->si_uid;
sb->st_gid = dev->si_gid;
sb->st_mode = dev->si_mode | S_IFCHR;
return (0);
}
#endif
static int ptsdev_close(struct lwp_tty *tp, struct rt_thread *td)
{
/* Deallocate TTY device. */
tty_lock(tp);
tty_rel_gone(tp);
#ifdef USING_BSD_VNODE
/* TODO: consider the vnode operation on DFS */
/*
* Open of /dev/ptmx or /dev/ptyXX changes the type of file
* from DTYPE_VNODE to DTYPE_PTS. vn_open() increases vnode
* use count, we need to decrement it, and possibly do other
* required cleanup.
*/
if (fp->f_vnode != NULL)
return (vnops.fo_close(fp, td));
#endif /* USING_BSD_VNODE */
return 0;
}
#ifdef USING_BSD_KINFO
static int ptsdev_fill_kinfo(struct file *fp, struct kinfo_file *kif,
struct filedesc *fdp)
{
struct lwp_tty *tp;
kif->kf_type = KF_TYPE_PTS;
tp = fp->f_data;
kif->kf_un.kf_pts.kf_pts_dev = tty_udev(tp);
kif->kf_un.kf_pts.kf_pts_dev_freebsd11 =
kif->kf_un.kf_pts.kf_pts_dev; /* truncate */
strlcpy(kif->kf_path, tty_devname(tp), sizeof(kif->kf_path));
return (0);
}
#endif
struct bsd_fileops bsd_ptsdev_methods = {
.fo_read = ptsdev_read,
.fo_write = ptsdev_write,
// .fo_truncate = invfo_truncate,
.fo_ioctl = ptsdev_ioctl,
.fo_poll = ptsdev_poll,
// .fo_kqfilter = ptsdev_kqfilter,
// .fo_stat = ptsdev_stat,
.fo_close = ptsdev_close,
// .fo_chmod = invfo_chmod,
// .fo_chown = invfo_chown,
// .fo_sendfile = invfo_sendfile,
// .fo_fill_kinfo = ptsdev_fill_kinfo,
.fo_flags = DFLAG_PASSABLE,
};
/*
* Driver-side hooks.
*/
static void ptsdrv_outwakeup(struct lwp_tty *tp)
{
struct pts_softc *psc = tty_softc(tp);
cv_broadcast(&psc->pts_outwait);
rt_wqueue_wakeup_all(&psc->pts_outpoll, (void *)POLLIN);
}
static void ptsdrv_inwakeup(struct lwp_tty *tp)
{
struct pts_softc *psc = tty_softc(tp);
cv_broadcast(&psc->pts_inwait);
rt_wqueue_wakeup_all(&psc->pts_inpoll, (void *)POLLOUT);
}
static int ptsdrv_open(struct lwp_tty *tp)
{
struct pts_softc *psc = tty_softc(tp);
/* for ioctl(TIOCSPTLCK) */
if (psc->pts_flags & PTS_PTLOCKED)
return -EIO;
psc->pts_flags &= ~PTS_FINISHED;
return 0;
}
static void ptsdrv_close(struct lwp_tty *tp)
{
struct pts_softc *psc = tty_softc(tp);
/* Wake up any blocked readers/writers. */
psc->pts_flags |= PTS_FINISHED;
ptsdrv_outwakeup(tp);
ptsdrv_inwakeup(tp);
}
static void ptsdrv_pktnotify(struct lwp_tty *tp, char event)
{
struct pts_softc *psc = tty_softc(tp);
/*
* Clear conflicting flags.
*/
switch (event)
{
case TIOCPKT_STOP:
psc->pts_pkt &= ~TIOCPKT_START;
break;
case TIOCPKT_START:
psc->pts_pkt &= ~TIOCPKT_STOP;
break;
case TIOCPKT_NOSTOP:
psc->pts_pkt &= ~TIOCPKT_DOSTOP;
break;
case TIOCPKT_DOSTOP:
psc->pts_pkt &= ~TIOCPKT_NOSTOP;
break;
}
psc->pts_pkt |= event;
/**
* Note: on smart, we don't wakeup master until it's willing to accept
* packet event. Because on poll, we setup POLLIN for PTS_PKT only. So There
* is a chance when we wakeup ipc but we can't wakeup user again. Since
* current wakeup will remove the wakequeue node on the meanwhile
*/
if (psc->pts_flags & PTS_PKT)
ptsdrv_outwakeup(tp);
}
static void ptsdrv_free(void *softc)
{
struct pts_softc *psc = softc;
/* Make device number available again. */
if (psc->pts_unit >= 0)
ptyfs_unregister_pts(psc->pts_master, psc->pts_unit);
#ifdef USING_BSD_UCRED
chgptscnt(psc->pts_cred->cr_ruidinfo, -1, 0);
racct_sub_cred(psc->pts_cred, RACCT_NPTS, 1);
crfree(psc->pts_cred);
#endif
rt_wqueue_wakeup_all(&psc->pts_inpoll, (void *)POLLHUP);
rt_wqueue_wakeup_all(&psc->pts_outpoll, (void *)POLLHUP);
rt_free(psc);
}
static struct lwp_ttydevsw pts_class = {
.tsw_flags = TF_NOPREFIX,
.tsw_outwakeup = ptsdrv_outwakeup,
.tsw_inwakeup = ptsdrv_inwakeup,
.tsw_open = ptsdrv_open,
.tsw_close = ptsdrv_close,
.tsw_pktnotify = ptsdrv_pktnotify,
.tsw_free = ptsdrv_free,
};
int pts_alloc(int fflags, struct rt_thread *td, struct dfs_file *ptm_file)
{
int unit;
struct lwp_tty *tp;
struct pts_softc *psc;
char name_buf[DIRENT_NAME_MAX];
const char *rootpath;
rt_device_t ptmx_device = ptm_file->vnode->data;
#ifdef USING_BSD_UCRED
struct rt_lwp *p = td->lwp;
int ok, error;
struct ucred *cred = td->td_ucred;
#endif
/* Resource limiting. */
#ifdef USING_BSD_UCRED
LWP_LOCK(p);
error = racct_add(p, RACCT_NPTS, 1);
if (error != 0)
{
LWP_UNLOCK(p);
return -EAGAIN;
}
ok = chgptscnt(cred->cr_ruidinfo, 1, lim_cur(td, RLIMIT_NPTS));
if (!ok)
{
racct_sub(p, RACCT_NPTS, 1);
LWP_UNLOCK(p);
return -EAGAIN;
}
LWP_UNLOCK(p);
#endif
/* Allocate TTY and softc. */
psc = rt_calloc(1, sizeof(struct pts_softc));
cv_init(&psc->pts_inwait, "ptsin");
cv_init(&psc->pts_outwait, "ptsout");
rt_wqueue_init(&psc->pts_inpoll);
rt_wqueue_init(&psc->pts_outpoll);
psc->pts_master = ptmx_device;
#ifdef USING_BSD_UCRED
psc->pts_cred = crhold(cred);
#else
psc->pts_cred = 0;
#endif
tp = lwp_tty_create(&pts_class, psc);
if (!tp)
{
rt_free(psc);
rt_condvar_detach(&psc->pts_inwait);
rt_condvar_detach(&psc->pts_outwait);
return -ENOMEM;
}
/* Try to allocate a new pts uint*/
unit = ptyfs_register_pts(ptmx_device, &tp->parent);
if (unit < 0)
{
#ifdef USING_BSD_UCRED
racct_sub(p, RACCT_NPTS, 1);
chgptscnt(cred->cr_ruidinfo, -1, 0);
#endif
lwp_tty_delete(tp);
return -EAGAIN;
}
psc->pts_unit = unit;
/* Expose the slave device as well. */
#ifdef USING_BSD_UCRED
tty_makedev(tp, td->td_ucred, "pts/%u", psc->pts_unit);
#else
rootpath = ptyfs_get_rootpath(ptmx_device);
RT_ASSERT(rootpath[strlen(rootpath) - 1] != '/');
snprintf(name_buf, DIRENT_NAME_MAX, "%s/%d", rootpath, psc->pts_unit);
/* setup the pts */
lwp_tty_register(tp, name_buf);
/* now this file operating on new pty */
ptm_file->data = tp;
#endif
return 0;
}
void pts_set_lock(lwp_tty_t pts, rt_bool_t is_lock)
{
struct pts_softc *psc = tty_softc(pts);
if (is_lock)
psc->pts_flags |= PTS_PTLOCKED;
else
psc->pts_flags &= ~PTS_PTLOCKED;
}
rt_bool_t pts_is_locked(lwp_tty_t pts)
{
struct pts_softc *psc = tty_softc(pts);
return !!(psc->pts_flags & PTS_PTLOCKED);
}
int pts_get_pktmode(lwp_tty_t pts)
{
struct pts_softc *psc = tty_softc(pts);
return !!(psc->pts_flags & PTS_PKT);
}