NetBSD/lib/libevent/kqueue.c

379 lines
8.5 KiB
C

/* $NetBSD: kqueue.c,v 1.5 2005/04/17 07:20:00 provos Exp $ */
/* $OpenBSD: kqueue.c,v 1.5 2002/07/10 14:41:31 art Exp $ */
/*
* Copyright 2000-2002 Niels Provos <provos@citi.umich.edu>
* 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 Niels Provos.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <sys/types.h>
#ifdef HAVE_SYS_TIME_H
#include <sys/time.h>
#else
#include <sys/_time.h>
#endif
#include <sys/queue.h>
#include <sys/event.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <errno.h>
#ifdef HAVE_INTTYPES_H
#include <inttypes.h>
#endif
#if defined(HAVE_INTTYPES_H) && !defined(__OpenBSD__) && !defined(__FreeBSD__)
#define INTPTR(x) (intptr_t)x
#else
#define INTPTR(x) x
#endif
#include "event.h"
#include "log.h"
#define EVLIST_X_KQINKERNEL 0x1000
#define NEVENT 64
struct kqop {
struct kevent *changes;
int nchanges;
struct kevent *events;
int nevents;
int kq;
};
void *kq_init (void);
int kq_add (void *, struct event *);
int kq_del (void *, struct event *);
int kq_recalc (struct event_base *, void *, int);
int kq_dispatch (struct event_base *, void *, struct timeval *);
int kq_insert (struct kqop *, struct kevent *);
const struct eventop kqops = {
"kqueue",
kq_init,
kq_add,
kq_del,
kq_recalc,
kq_dispatch
};
void *
kq_init(void)
{
int kq;
struct kqop *kqueueop;
/* Disable kqueue when this environment variable is set */
if (getenv("EVENT_NOKQUEUE"))
return (NULL);
if (!(kqueueop = calloc(1, sizeof(struct kqop))))
return (NULL);
/* Initalize the kernel queue */
if ((kq = kqueue()) == -1) {
event_warn("kqueue");
free (kqueueop);
return (NULL);
}
kqueueop->kq = kq;
/* Initalize fields */
kqueueop->changes = malloc(NEVENT * sizeof(struct kevent));
if (kqueueop->changes == NULL) {
free (kqueueop);
return (NULL);
}
kqueueop->events = malloc(NEVENT * sizeof(struct kevent));
if (kqueueop->events == NULL) {
free (kqueueop->changes);
free (kqueueop);
return (NULL);
}
kqueueop->nevents = NEVENT;
return (kqueueop);
}
int
kq_recalc(struct event_base *base, void *arg, int max)
{
return (0);
}
int
kq_insert(struct kqop *kqop, struct kevent *kev)
{
int nevents = kqop->nevents;
if (kqop->nchanges == nevents) {
struct kevent *newchange;
struct kevent *newresult;
nevents *= 2;
newchange = realloc(kqop->changes,
nevents * sizeof(struct kevent));
if (newchange == NULL) {
event_warn("%s: malloc", __func__);
return (-1);
}
kqop->changes = newchange;
newresult = realloc(kqop->events,
nevents * sizeof(struct kevent));
/*
* If we fail, we don't have to worry about freeing,
* the next realloc will pick it up.
*/
if (newresult == NULL) {
event_warn("%s: malloc", __func__);
return (-1);
}
kqop->events = newresult;
kqop->nevents = nevents;
}
memcpy(&kqop->changes[kqop->nchanges++], kev, sizeof(struct kevent));
event_debug(("%s: fd %d %s%s",
__func__, kev->ident,
kev->filter == EVFILT_READ ? "EVFILT_READ" : "EVFILT_WRITE",
kev->flags == EV_DELETE ? " (del)" : ""));
return (0);
}
static void
kq_sighandler(int sig)
{
/* Do nothing here */
}
int
kq_dispatch(struct event_base *base, void *arg, struct timeval *tv)
{
struct kqop *kqop = arg;
struct kevent *changes = kqop->changes;
struct kevent *events = kqop->events;
struct event *ev;
struct timespec ts;
int i, res;
TIMEVAL_TO_TIMESPEC(tv, &ts);
res = kevent(kqop->kq, changes, kqop->nchanges,
events, kqop->nevents, &ts);
kqop->nchanges = 0;
if (res == -1) {
if (errno != EINTR) {
event_warn("kevent");
return (-1);
}
return (0);
}
event_debug(("%s: kevent reports %d", __func__, res));
for (i = 0; i < res; i++) {
int which = 0;
if (events[i].flags & EV_ERROR) {
/*
* Error messages that can happen, when a delete fails.
* EBADF happens when the file discriptor has been
* closed,
* ENOENT when the file discriptor was closed and
* then reopened.
* An error is also indicated when a callback deletes
* an event we are still processing. In that case
* the data field is set to ENOENT.
*/
if (events[i].data == EBADF ||
events[i].data == ENOENT)
continue;
errno = events[i].data;
return (-1);
}
ev = (struct event *)events[i].udata;
if (events[i].filter == EVFILT_READ) {
which |= EV_READ;
} else if (events[i].filter == EVFILT_WRITE) {
which |= EV_WRITE;
} else if (events[i].filter == EVFILT_SIGNAL) {
which |= EV_SIGNAL;
}
if (!which)
continue;
if (!(ev->ev_events & EV_PERSIST)) {
ev->ev_flags &= ~EVLIST_X_KQINKERNEL;
event_del(ev);
}
event_active(ev, which,
ev->ev_events & EV_SIGNAL ? events[i].data : 1);
}
return (0);
}
int
kq_add(void *arg, struct event *ev)
{
struct kqop *kqop = arg;
struct kevent kev;
if (ev->ev_events & EV_SIGNAL) {
int nsignal = EVENT_SIGNAL(ev);
memset(&kev, 0, sizeof(kev));
kev.ident = nsignal;
kev.filter = EVFILT_SIGNAL;
kev.flags = EV_ADD;
if (!(ev->ev_events & EV_PERSIST))
kev.flags |= EV_ONESHOT;
kev.udata = INTPTR(ev);
if (kq_insert(kqop, &kev) == -1)
return (-1);
if (signal(nsignal, kq_sighandler) == SIG_ERR)
return (-1);
ev->ev_flags |= EVLIST_X_KQINKERNEL;
return (0);
}
if (ev->ev_events & EV_READ) {
memset(&kev, 0, sizeof(kev));
kev.ident = ev->ev_fd;
kev.filter = EVFILT_READ;
#ifdef NOTE_EOF
/* Make it behave like select() and poll() */
kev.fflags = NOTE_EOF;
#endif
kev.flags = EV_ADD;
if (!(ev->ev_events & EV_PERSIST))
kev.flags |= EV_ONESHOT;
kev.udata = INTPTR(ev);
if (kq_insert(kqop, &kev) == -1)
return (-1);
ev->ev_flags |= EVLIST_X_KQINKERNEL;
}
if (ev->ev_events & EV_WRITE) {
memset(&kev, 0, sizeof(kev));
kev.ident = ev->ev_fd;
kev.filter = EVFILT_WRITE;
kev.flags = EV_ADD;
if (!(ev->ev_events & EV_PERSIST))
kev.flags |= EV_ONESHOT;
kev.udata = INTPTR(ev);
if (kq_insert(kqop, &kev) == -1)
return (-1);
ev->ev_flags |= EVLIST_X_KQINKERNEL;
}
return (0);
}
int
kq_del(void *arg, struct event *ev)
{
struct kqop *kqop = arg;
struct kevent kev;
if (!(ev->ev_flags & EVLIST_X_KQINKERNEL))
return (0);
if (ev->ev_events & EV_SIGNAL) {
int nsignal = EVENT_SIGNAL(ev);
memset(&kev, 0, sizeof(kev));
kev.ident = (int)signal;
kev.filter = EVFILT_SIGNAL;
kev.flags = EV_DELETE;
if (kq_insert(kqop, &kev) == -1)
return (-1);
if (signal(nsignal, SIG_DFL) == SIG_ERR)
return (-1);
ev->ev_flags &= ~EVLIST_X_KQINKERNEL;
return (0);
}
if (ev->ev_events & EV_READ) {
memset(&kev, 0, sizeof(kev));
kev.ident = ev->ev_fd;
kev.filter = EVFILT_READ;
kev.flags = EV_DELETE;
if (kq_insert(kqop, &kev) == -1)
return (-1);
ev->ev_flags &= ~EVLIST_X_KQINKERNEL;
}
if (ev->ev_events & EV_WRITE) {
memset(&kev, 0, sizeof(kev));
kev.ident = ev->ev_fd;
kev.filter = EVFILT_WRITE;
kev.flags = EV_DELETE;
if (kq_insert(kqop, &kev) == -1)
return (-1);
ev->ev_flags &= ~EVLIST_X_KQINKERNEL;
}
return (0);
}