/**
* @file
*
* @ingroup rtems_bsd_rtems
*
* @brief TODO.
*/
/*
* Copyright (c) 2017 embedded brains GmbH.
* All rights reserved.
*
* embedded brains GmbH
* Dornierstr. 4
* 82178 Puchheim
* Germany
* <rtems@embedded-brains.de>
*
* 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.
*/
#include <machine/rtems-bsd-kernel-space.h>
#include <sys/cdefs.h>
#include <sys/types.h>
#include <sys/errno.h>
#include <sys/event.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/pcpu.h>
#include <sys/poll.h>
#include <sys/selinfo.h>
#include <rtems/termiostypes.h>
#include <rtems/irq-extension.h>
SYSINIT_REFERENCE(irqs);
typedef struct {
rtems_termios_tty *tty;
struct selinfo sel;
rtems_interrupt_server_request request;
} termios_selinfo;
static bool
termios_is_eol(const rtems_termios_tty *tty, char c)
{
return (c == '\n' || c == tty->termios.c_cc[VEOF] ||
c == tty->termios.c_cc[VEOL] ||
c == tty->termios.c_cc[VEOL2]);
}
static bool
termios_can_read(rtems_termios_tty *tty)
{
rtems_termios_device_context *ctx;
rtems_interrupt_lock_context lock_context;
unsigned int i;
unsigned int size;
unsigned int raw_content_size;
bool can;
if (tty->handler.mode == TERMIOS_POLLED) {
return (true);
}
if (tty->cindex != tty->ccount) {
return (true);
}
ctx = tty->device_context;
rtems_termios_device_lock_acquire(ctx, &lock_context);
i = tty->rawInBuf.Head;
size = tty->rawInBuf.Size;
raw_content_size = (tty->rawInBuf.Tail - i) % size;
if ((tty->termios.c_lflag & ICANON) != 0) {
unsigned int todo = raw_content_size;
/*
* FIXME: What to do in case of a raw input buffer overflow?
* For now, indicated that we can read. However, this has
* problems in case an erase takes place.
*/
can = raw_content_size == (size - 1);
while (todo > 0 && !can) {
char c;
i = (i + 1) % size;
c = tty->rawInBuf.theBuf[i];
can = termios_is_eol(tty, c);
--todo;
}
} else {
cc_t vmin = tty->termios.c_cc[VMIN];
if (vmin == 0) {
vmin = 1;
}
can = raw_content_size >= vmin;
}
if (!can) {
tty->tty_rcvwakeup = false;
}
rtems_termios_device_lock_release(ctx, &lock_context);
return (can);
}
static bool
termios_can_write(const rtems_termios_tty *tty)
{
rtems_termios_device_context *ctx;
rtems_interrupt_lock_context lock_context;
bool can;
if (tty->handler.mode == TERMIOS_POLLED) {
return (true);
}
ctx = tty->device_context;
rtems_termios_device_lock_acquire(ctx, &lock_context);
can = ((tty->rawOutBuf.Tail - tty->rawOutBuf.Head - 1) %
tty->rawOutBuf.Size) > 0;
rtems_termios_device_lock_release(ctx, &lock_context);
return (can);
}
static void
termios_receive_wakeup(void *arg)
{
termios_selinfo *ts;
rtems_termios_tty *tty;
ts = arg;
tty = ts->tty;
rtems_mutex_lock(&tty->isem);
selwakeup(&ts->sel);
rtems_mutex_unlock(&tty->isem);
}
static void
termios_transmit_wakeup(void *arg)
{
termios_selinfo *ts;
rtems_termios_tty *tty;
ts = arg;
tty = ts->tty;
rtems_mutex_lock(&tty->osem);
selwakeup(&ts->sel);
rtems_mutex_unlock(&tty->osem);
}
static void
termios_wakeup(struct termios *term, void *arg)
{
termios_selinfo *ts = arg;
rtems_interrupt_server_request_submit(&ts->request);
}
static struct selinfo *
termios_get_selinfo(rtems_termios_tty *tty, struct ttywakeup *wk,
rtems_interrupt_handler handler)
{
termios_selinfo *ts = wk->sw_arg;
if (ts == NULL) {
BSD_ASSERT(wk->sw_pfn == NULL);
ts = malloc(sizeof(*ts), M_TEMP, M_WAITOK | M_ZERO);
ts->tty = tty;
rtems_interrupt_server_request_initialize(RTEMS_INTERRUPT_SERVER_DEFAULT,
&ts->request, handler, ts);
wk->sw_arg = ts;
wk->sw_pfn = termios_wakeup;
} else {
BSD_ASSERT(wk->sw_pfn == termios_wakeup);
}
return (&ts->sel);
}
int
rtems_termios_kqfilter(rtems_libio_t *iop, struct knote *kn)
{
return (EINVAL);
}
int
rtems_termios_poll(rtems_libio_t *iop, int events)
{
struct thread *td = rtems_bsd_get_curthread_or_wait_forever();
struct selinfo *sel;
rtems_termios_tty *tty;
int revents;
revents = 0;
tty = iop->data1;
if ((events & (POLLIN | POLLRDNORM)) != 0) {
sel = termios_get_selinfo(tty, &tty->tty_rcv,
termios_receive_wakeup);
rtems_mutex_lock(&tty->isem);
if (termios_can_read(tty)) {
revents |= events & (POLLIN | POLLRDNORM);
} else {
selrecord(td, sel);
}
rtems_mutex_unlock(&tty->isem);
}
if ((events & (POLLOUT | POLLWRNORM)) != 0) {
sel = termios_get_selinfo(tty, &tty->tty_snd,
termios_transmit_wakeup);
rtems_mutex_lock(&tty->osem);
if (termios_can_write(tty)) {
revents |= events & (POLLOUT | POLLWRNORM);
} else {
selrecord(td, sel);
}
rtems_mutex_unlock(&tty->osem);
}
return (revents);
}
static void
termioskqueuepoll_sysinit(void)
{
/* Do nothing */
}
SYSINIT(termioskqueuepoll, SI_SUB_TUNABLES, SI_ORDER_ANY,
termioskqueuepoll_sysinit, NULL);
