/* $NetBSD: event.c,v 1.17 2021/09/26 16:36:18 thorpej Exp $ */
/*
* Copyright (c) 1992, 1993
* The Regents of the University of California. All rights reserved.
*
* This software was developed by the Computer Systems Engineering group
* at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
* contributed to Berkeley.
*
* 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, Lawrence Berkeley Laboratory.
*
* 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. 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.
*
* @(#)event.c 8.1 (Berkeley) 6/11/93
*
* from: Header: event.c,v 1.5 92/11/26 01:10:44 torek Exp (LBL)
*/
/*
* Internal `Firm_event' interface for the keyboard and mouse drivers.
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: event.c,v 1.17 2021/09/26 16:36:18 thorpej Exp $");
#include <sys/param.h>
#include <sys/fcntl.h>
#include <sys/kmem.h>
#include <sys/proc.h>
#include <sys/systm.h>
#include <sys/vnode.h>
#include <sys/select.h>
#include <sys/poll.h>
#include <atari/dev/vuid_event.h>
#include <atari/dev/event_var.h>
#define EV_Q_ALLOCSIZE (EV_QSIZE * sizeof(struct firm_event))
/*
* Initialize a firm_event queue.
*/
void
ev_init(register struct evvar *ev)
{
ev->ev_get = ev->ev_put = 0;
ev->ev_q = kmem_zalloc(EV_Q_ALLOCSIZE, KM_SLEEP);
selinit(&ev->ev_sel);
}
/*
* Tear down a firm_event queue.
*/
void
ev_fini(register struct evvar *ev)
{
seldestroy(&ev->ev_sel);
kmem_free(ev->ev_q, EV_Q_ALLOCSIZE);
}
/*
* User-level interface: read, select.
* (User cannot write an event queue.)
*/
int
ev_read(register struct evvar *ev, struct uio *uio, int flags)
{
int s, n, cnt, error;
/*
* Make sure we can return at least 1.
*/
if (uio->uio_resid < sizeof(struct firm_event))
return (EMSGSIZE); /* ??? */
s = splev();
while (ev->ev_get == ev->ev_put) {
if (flags & IO_NDELAY) {
splx(s);
return (EWOULDBLOCK);
}
ev->ev_wanted = 1;
error = tsleep((void *)ev, PEVENT | PCATCH, "firm_event", 0);
if (error) {
splx(s);
return (error);
}
}
/*
* Move firm_events from tail end of queue (there is at least one
* there).
*/
if (ev->ev_put < ev->ev_get)
cnt = EV_QSIZE - ev->ev_get; /* events in [get..QSIZE) */
else
cnt = ev->ev_put - ev->ev_get; /* events in [get..put) */
splx(s);
n = howmany(uio->uio_resid, sizeof(struct firm_event));
if (cnt > n)
cnt = n;
error = uiomove((void *)&ev->ev_q[ev->ev_get],
cnt * sizeof(struct firm_event), uio);
n -= cnt;
/*
* If we do not wrap to 0, used up all our space, or had an error,
* stop. Otherwise move from front of queue to put index, if there
* is anything there to move.
*/
if ((ev->ev_get = (ev->ev_get + cnt) % EV_QSIZE) != 0 ||
n == 0 || error || (cnt = ev->ev_put) == 0)
return (error);
if (cnt > n)
cnt = n;
error = uiomove((void *)&ev->ev_q[0],
cnt * sizeof(struct firm_event), uio);
ev->ev_get = cnt;
return (error);
}
int
ev_poll(register struct evvar *ev, int events, struct lwp *l)
{
int revents = 0;
int s = splev();
if (events & (POLLIN | POLLRDNORM)) {
if (ev->ev_get != ev->ev_put)
revents |= events & (POLLIN | POLLRDNORM);
else
selrecord(l, &ev->ev_sel);
}
splx(s);
return (revents);
}
static void
filt_evrdetach(struct knote *kn)
{
struct evvar *ev = kn->kn_hook;
int s;
s = splev();
selremove_knote(&ev->ev_sel, kn);
splx(s);
}
static int
filt_evread(struct knote *kn, long hint)
{
struct evvar *ev = kn->kn_hook;
if (ev->ev_get == ev->ev_put)
return (0);
if (ev->ev_get < ev->ev_put)
kn->kn_data = ev->ev_put - ev->ev_get;
else
kn->kn_data = (EV_QSIZE - ev->ev_get) +
ev->ev_put;
kn->kn_data *= sizeof(struct firm_event);
return (1);
}
static const struct filterops ev_filtops = {
.f_flags = FILTEROP_ISFD,
.f_attach = NULL,
.f_detach = filt_evrdetach,
.f_event = filt_evread,
};
int
ev_kqfilter(struct evvar *ev, struct knote *kn)
{
int s;
switch (kn->kn_filter) {
case EVFILT_READ:
kn->kn_fop = &ev_filtops;
break;
default:
return (EINVAL);
}
kn->kn_hook = ev;
s = splev();
selrecord_knote(&ev->ev_sel, kn);
splx(s);
return (0);
}
