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-rw-r--r--third_party/libevent/kqueue.c449
1 files changed, 449 insertions, 0 deletions
diff --git a/third_party/libevent/kqueue.c b/third_party/libevent/kqueue.c
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+/* $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. 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>
+#include <assert.h>
+#ifdef HAVE_INTTYPES_H
+#include <inttypes.h>
+#endif
+
+/* Some platforms apparently define the udata field of struct kevent as
+ * intptr_t, whereas others define it as void*. There doesn't seem to be an
+ * easy way to tell them apart via autoconf, so we need to use OS macros. */
+#if defined(HAVE_INTTYPES_H) && !defined(__OpenBSD__) && !defined(__FreeBSD__) && !defined(__darwin__) && !defined(__APPLE__)
+#define PTR_TO_UDATA(x) ((intptr_t)(x))
+#else
+#define PTR_TO_UDATA(x) (x)
+#endif
+
+#include "event.h"
+#include "event-internal.h"
+#include "log.h"
+#include "event-internal.h"
+
+#define EVLIST_X_KQINKERNEL 0x1000
+
+#define NEVENT 64
+
+struct kqop {
+ struct kevent *changes;
+ int nchanges;
+ struct kevent *events;
+ struct event_list evsigevents[NSIG];
+ int nevents;
+ int kq;
+ pid_t pid;
+};
+
+static void *kq_init (struct event_base *);
+static int kq_add (void *, struct event *);
+static int kq_del (void *, struct event *);
+static int kq_dispatch (struct event_base *, void *, struct timeval *);
+static int kq_insert (struct kqop *, struct kevent *);
+static void kq_dealloc (struct event_base *, void *);
+
+const struct eventop kqops = {
+ "kqueue",
+ kq_init,
+ kq_add,
+ kq_del,
+ kq_dispatch,
+ kq_dealloc,
+ 1 /* need reinit */
+};
+
+static void *
+kq_init(struct event_base *base)
+{
+ int i, 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;
+
+ kqueueop->pid = getpid();
+
+ /* 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;
+
+ /* we need to keep track of multiple events per signal */
+ for (i = 0; i < NSIG; ++i) {
+ TAILQ_INIT(&kqueueop->evsigevents[i]);
+ }
+
+ /* Check for Mac OS X kqueue bug. */
+ kqueueop->changes[0].ident = -1;
+ kqueueop->changes[0].filter = EVFILT_READ;
+ kqueueop->changes[0].flags = EV_ADD;
+ /*
+ * If kqueue works, then kevent will succeed, and it will
+ * stick an error in events[0]. If kqueue is broken, then
+ * kevent will fail.
+ */
+ if (kevent(kq,
+ kqueueop->changes, 1, kqueueop->events, NEVENT, NULL) != 1 ||
+ kqueueop->events[0].ident != -1 ||
+ kqueueop->events[0].flags != EV_ERROR) {
+ event_warn("%s: detected broken kqueue; not using.", __func__);
+ free(kqueueop->changes);
+ free(kqueueop->events);
+ free(kqueueop);
+ close(kq);
+ return (NULL);
+ }
+
+ return (kqueueop);
+}
+
+static 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__, (int)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 */
+}
+
+static 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, *ts_p = NULL;
+ int i, res;
+
+ if (tv != NULL) {
+ TIMEVAL_TO_TIMESPEC(tv, &ts);
+ ts_p = &ts;
+ }
+
+ res = kevent(kqop->kq, changes, kqop->nchanges,
+ events, kqop->nevents, ts_p);
+ 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.
+ * EINVAL for some reasons not understood; EINVAL
+ * should not be returned ever; but FreeBSD does :-\
+ * 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 == EINVAL ||
+ events[i].data == ENOENT)
+ continue;
+ errno = events[i].data;
+ return (-1);
+ }
+
+ 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 (events[i].filter == EVFILT_SIGNAL) {
+ struct event_list *head =
+ (struct event_list *)events[i].udata;
+ TAILQ_FOREACH(ev, head, ev_signal_next) {
+ event_active(ev, which, events[i].data);
+ }
+ } else {
+ ev = (struct event *)events[i].udata;
+
+ if (!(ev->ev_events & EV_PERSIST))
+ ev->ev_flags &= ~EVLIST_X_KQINKERNEL;
+
+ event_active(ev, which, 1);
+ }
+ }
+
+ return (0);
+}
+
+
+static 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);
+
+ assert(nsignal >= 0 && nsignal < NSIG);
+ if (TAILQ_EMPTY(&kqop->evsigevents[nsignal])) {
+ struct timespec timeout = { 0, 0 };
+
+ memset(&kev, 0, sizeof(kev));
+ kev.ident = nsignal;
+ kev.filter = EVFILT_SIGNAL;
+ kev.flags = EV_ADD;
+ kev.udata = PTR_TO_UDATA(&kqop->evsigevents[nsignal]);
+
+ /* Be ready for the signal if it is sent any
+ * time between now and the next call to
+ * kq_dispatch. */
+ if (kevent(kqop->kq, &kev, 1, NULL, 0, &timeout) == -1)
+ return (-1);
+
+ if (_evsignal_set_handler(ev->ev_base, nsignal,
+ kq_sighandler) == -1)
+ return (-1);
+ }
+
+ TAILQ_INSERT_TAIL(&kqop->evsigevents[nsignal], ev,
+ ev_signal_next);
+ 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 = PTR_TO_UDATA(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 = PTR_TO_UDATA(ev);
+
+ if (kq_insert(kqop, &kev) == -1)
+ return (-1);
+
+ ev->ev_flags |= EVLIST_X_KQINKERNEL;
+ }
+
+ return (0);
+}
+
+static 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);
+ struct timespec timeout = { 0, 0 };
+
+ assert(nsignal >= 0 && nsignal < NSIG);
+ TAILQ_REMOVE(&kqop->evsigevents[nsignal], ev, ev_signal_next);
+ if (TAILQ_EMPTY(&kqop->evsigevents[nsignal])) {
+ memset(&kev, 0, sizeof(kev));
+ kev.ident = nsignal;
+ kev.filter = EVFILT_SIGNAL;
+ kev.flags = EV_DELETE;
+
+ /* Because we insert signal events
+ * immediately, we need to delete them
+ * immediately, too */
+ if (kevent(kqop->kq, &kev, 1, NULL, 0, &timeout) == -1)
+ return (-1);
+
+ if (_evsignal_restore_handler(ev->ev_base,
+ nsignal) == -1)
+ 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);
+}
+
+static void
+kq_dealloc(struct event_base *base, void *arg)
+{
+ struct kqop *kqop = arg;
+
+ if (kqop->changes)
+ free(kqop->changes);
+ if (kqop->events)
+ free(kqop->events);
+ if (kqop->kq >= 0 && kqop->pid == getpid())
+ close(kqop->kq);
+ memset(kqop, 0, sizeof(struct kqop));
+ free(kqop);
+}
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