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-rw-r--r--libevent/kqueue.c580
1 files changed, 580 insertions, 0 deletions
diff --git a/libevent/kqueue.c b/libevent/kqueue.c
new file mode 100644
index 0000000..dfd7751
--- /dev/null
+++ b/libevent/kqueue.c
@@ -0,0 +1,580 @@
+/* $OpenBSD: kqueue.c,v 1.5 2002/07/10 14:41:31 art Exp $ */
+
+/*
+ * Copyright 2000-2007 Niels Provos <provos@citi.umich.edu>
+ * Copyright 2007-2012 Niels Provos and Nick Mathewson
+ *
+ * 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.
+ */
+#include "event2/event-config.h"
+#include "evconfig-private.h"
+
+#ifdef EVENT__HAVE_KQUEUE
+
+#include <sys/types.h>
+#ifdef EVENT__HAVE_SYS_TIME_H
+#include <sys/time.h>
+#endif
+#include <sys/queue.h>
+#include <sys/event.h>
+#include <limits.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#ifdef EVENT__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(__NetBSD__)
+#define PTR_TO_UDATA(x) ((typeof(((struct kevent *)0)->udata))(x))
+#define INT_TO_UDATA(x) ((typeof(((struct kevent *)0)->udata))(intptr_t)(x))
+#elif defined(EVENT__HAVE_INTTYPES_H) && !defined(__OpenBSD__) && !defined(__FreeBSD__) && !defined(__darwin__) && !defined(__APPLE__) && !defined(__CloudABI__)
+#define PTR_TO_UDATA(x) ((intptr_t)(x))
+#define INT_TO_UDATA(x) ((intptr_t)(x))
+#else
+#define PTR_TO_UDATA(x) (x)
+#define INT_TO_UDATA(x) ((void*)(x))
+#endif
+
+#include "event-internal.h"
+#include "log-internal.h"
+#include "evmap-internal.h"
+#include "event2/thread.h"
+#include "event2/util.h"
+#include "evthread-internal.h"
+#include "changelist-internal.h"
+
+#include "kqueue-internal.h"
+
+#define NEVENT 64
+
+struct kqop {
+ struct kevent *changes;
+ int changes_size;
+
+ struct kevent *events;
+ int events_size;
+ int kq;
+ int notify_event_added;
+ pid_t pid;
+};
+
+static void kqop_free(struct kqop *kqop);
+
+static void *kq_init(struct event_base *);
+static int kq_sig_add(struct event_base *, int, short, short, void *);
+static int kq_sig_del(struct event_base *, int, short, short, void *);
+static int kq_dispatch(struct event_base *, struct timeval *);
+static void kq_dealloc(struct event_base *);
+
+const struct eventop kqops = {
+ "kqueue",
+ kq_init,
+ event_changelist_add_,
+ event_changelist_del_,
+ kq_dispatch,
+ kq_dealloc,
+ 1 /* need reinit */,
+ EV_FEATURE_ET|EV_FEATURE_O1|EV_FEATURE_FDS,
+ EVENT_CHANGELIST_FDINFO_SIZE
+};
+
+static const struct eventop kqsigops = {
+ "kqueue_signal",
+ NULL,
+ kq_sig_add,
+ kq_sig_del,
+ NULL,
+ NULL,
+ 1 /* need reinit */,
+ 0,
+ 0
+};
+
+static void *
+kq_init(struct event_base *base)
+{
+ int kq = -1;
+ struct kqop *kqueueop = NULL;
+
+ if (!(kqueueop = mm_calloc(1, sizeof(struct kqop))))
+ return (NULL);
+
+/* Initialize the kernel queue */
+
+ if ((kq = kqueue()) == -1) {
+ event_warn("kqueue");
+ goto err;
+ }
+
+ kqueueop->kq = kq;
+
+ kqueueop->pid = getpid();
+
+ /* Initialize fields */
+ kqueueop->changes = mm_calloc(NEVENT, sizeof(struct kevent));
+ if (kqueueop->changes == NULL)
+ goto err;
+ kqueueop->events = mm_calloc(NEVENT, sizeof(struct kevent));
+ if (kqueueop->events == NULL)
+ goto err;
+ kqueueop->events_size = kqueueop->changes_size = NEVENT;
+
+ /* Check for Mac OS X kqueue bug. */
+ memset(&kqueueop->changes[0], 0, sizeof kqueueop->changes[0]);
+ 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 ||
+ (int)kqueueop->events[0].ident != -1 ||
+ !(kqueueop->events[0].flags & EV_ERROR)) {
+ event_warn("%s: detected broken kqueue; not using.", __func__);
+ goto err;
+ }
+
+ base->evsigsel = &kqsigops;
+
+ return (kqueueop);
+err:
+ if (kqueueop)
+ kqop_free(kqueueop);
+
+ return (NULL);
+}
+
+#define ADD_UDATA 0x30303
+
+static void
+kq_setup_kevent(struct kevent *out, evutil_socket_t fd, int filter, short change)
+{
+ memset(out, 0, sizeof(struct kevent));
+ out->ident = fd;
+ out->filter = filter;
+
+ if (change & EV_CHANGE_ADD) {
+ out->flags = EV_ADD;
+ /* We set a magic number here so that we can tell 'add'
+ * errors from 'del' errors. */
+ out->udata = INT_TO_UDATA(ADD_UDATA);
+ if (change & EV_ET)
+ out->flags |= EV_CLEAR;
+#ifdef NOTE_EOF
+ /* Make it behave like select() and poll() */
+ if (filter == EVFILT_READ)
+ out->fflags = NOTE_EOF;
+#endif
+ } else {
+ EVUTIL_ASSERT(change & EV_CHANGE_DEL);
+ out->flags = EV_DELETE;
+ }
+}
+
+static int
+kq_build_changes_list(const struct event_changelist *changelist,
+ struct kqop *kqop)
+{
+ int i;
+ int n_changes = 0;
+
+ for (i = 0; i < changelist->n_changes; ++i) {
+ struct event_change *in_ch = &changelist->changes[i];
+ struct kevent *out_ch;
+ if (n_changes >= kqop->changes_size - 1) {
+ int newsize;
+ struct kevent *newchanges;
+
+ if (kqop->changes_size > INT_MAX / 2 ||
+ (size_t)kqop->changes_size * 2 > EV_SIZE_MAX /
+ sizeof(struct kevent)) {
+ event_warnx("%s: int overflow", __func__);
+ return (-1);
+ }
+
+ newsize = kqop->changes_size * 2;
+ newchanges = mm_realloc(kqop->changes,
+ newsize * sizeof(struct kevent));
+ if (newchanges == NULL) {
+ event_warn("%s: realloc", __func__);
+ return (-1);
+ }
+ kqop->changes = newchanges;
+ kqop->changes_size = newsize;
+ }
+ if (in_ch->read_change) {
+ out_ch = &kqop->changes[n_changes++];
+ kq_setup_kevent(out_ch, in_ch->fd, EVFILT_READ,
+ in_ch->read_change);
+ }
+ if (in_ch->write_change) {
+ out_ch = &kqop->changes[n_changes++];
+ kq_setup_kevent(out_ch, in_ch->fd, EVFILT_WRITE,
+ in_ch->write_change);
+ }
+ }
+ return n_changes;
+}
+
+static int
+kq_grow_events(struct kqop *kqop, size_t new_size)
+{
+ struct kevent *newresult;
+
+ newresult = mm_realloc(kqop->events,
+ new_size * sizeof(struct kevent));
+
+ if (newresult) {
+ kqop->events = newresult;
+ kqop->events_size = new_size;
+ return 0;
+ } else {
+ return -1;
+ }
+}
+
+static int
+kq_dispatch(struct event_base *base, struct timeval *tv)
+{
+ struct kqop *kqop = base->evbase;
+ struct kevent *events = kqop->events;
+ struct kevent *changes;
+ struct timespec ts, *ts_p = NULL;
+ int i, n_changes, res;
+
+ if (tv != NULL) {
+ ts.tv_sec = tv->tv_sec;
+ ts.tv_nsec = tv->tv_usec * 1000;
+ ts_p = &ts;
+ }
+
+ /* Build "changes" from "base->changes" */
+ EVUTIL_ASSERT(kqop->changes);
+ n_changes = kq_build_changes_list(&base->changelist, kqop);
+ if (n_changes < 0)
+ return -1;
+
+ event_changelist_remove_all_(&base->changelist, base);
+
+ /* steal the changes array in case some broken code tries to call
+ * dispatch twice at once. */
+ changes = kqop->changes;
+ kqop->changes = NULL;
+
+ /* Make sure that 'events' is at least as long as the list of changes:
+ * otherwise errors in the changes can get reported as a -1 return
+ * value from kevent() rather than as EV_ERROR events in the events
+ * array.
+ *
+ * (We could instead handle -1 return values from kevent() by
+ * retrying with a smaller changes array or a larger events array,
+ * but this approach seems less risky for now.)
+ */
+ if (kqop->events_size < n_changes) {
+ int new_size = kqop->events_size;
+ do {
+ new_size *= 2;
+ } while (new_size < n_changes);
+
+ kq_grow_events(kqop, new_size);
+ events = kqop->events;
+ }
+
+ EVBASE_RELEASE_LOCK(base, th_base_lock);
+
+ res = kevent(kqop->kq, changes, n_changes,
+ events, kqop->events_size, ts_p);
+
+ EVBASE_ACQUIRE_LOCK(base, th_base_lock);
+
+ EVUTIL_ASSERT(kqop->changes == NULL);
+ kqop->changes = changes;
+
+ 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) {
+ switch (events[i].data) {
+
+ /* Can occur on delete if we are not currently
+ * watching any events on this fd. That can
+ * happen when the fd was closed and another
+ * file was opened with that fd. */
+ case ENOENT:
+ /* Can occur for reasons not fully understood
+ * on FreeBSD. */
+ case EINVAL:
+ continue;
+#if defined(__FreeBSD__)
+ /*
+ * This currently occurs if an FD is closed
+ * before the EV_DELETE makes it out via kevent().
+ * The FreeBSD capabilities code sees the blank
+ * capability set and rejects the request to
+ * modify an event.
+ *
+ * To be strictly correct - when an FD is closed,
+ * all the registered events are also removed.
+ * Queuing EV_DELETE to a closed FD is wrong.
+ * The event(s) should just be deleted from
+ * the pending changelist.
+ */
+ case ENOTCAPABLE:
+ continue;
+#endif
+
+ /* Can occur on a delete if the fd is closed. */
+ case EBADF:
+ /* XXXX On NetBSD, we can also get EBADF if we
+ * try to add the write side of a pipe, but
+ * the read side has already been closed.
+ * Other BSDs call this situation 'EPIPE'. It
+ * would be good if we had a way to report
+ * this situation. */
+ continue;
+ /* These two can occur on an add if the fd was one side
+ * of a pipe, and the other side was closed. */
+ case EPERM:
+ case EPIPE:
+ /* Report read events, if we're listening for
+ * them, so that the user can learn about any
+ * add errors. (If the operation was a
+ * delete, then udata should be cleared.) */
+ if (events[i].udata) {
+ /* The operation was an add:
+ * report the error as a read. */
+ which |= EV_READ;
+ break;
+ } else {
+ /* The operation was a del:
+ * report nothing. */
+ continue;
+ }
+
+ /* Other errors shouldn't occur. */
+ default:
+ errno = events[i].data;
+ return (-1);
+ }
+ } else 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;
+#ifdef EVFILT_USER
+ } else if (events[i].filter == EVFILT_USER) {
+ base->is_notify_pending = 0;
+#endif
+ }
+
+ if (!which)
+ continue;
+
+ if (events[i].filter == EVFILT_SIGNAL) {
+ evmap_signal_active_(base, events[i].ident, 1);
+ } else {
+ evmap_io_active_(base, events[i].ident, which | EV_ET);
+ }
+ }
+
+ if (res == kqop->events_size) {
+ /* We used all the events space that we have. Maybe we should
+ make it bigger. */
+ kq_grow_events(kqop, kqop->events_size * 2);
+ }
+
+ return (0);
+}
+
+static void
+kqop_free(struct kqop *kqop)
+{
+ if (kqop->changes)
+ mm_free(kqop->changes);
+ if (kqop->events)
+ mm_free(kqop->events);
+ if (kqop->kq >= 0 && kqop->pid == getpid())
+ close(kqop->kq);
+ memset(kqop, 0, sizeof(struct kqop));
+ mm_free(kqop);
+}
+
+static void
+kq_dealloc(struct event_base *base)
+{
+ struct kqop *kqop = base->evbase;
+ evsig_dealloc_(base);
+ kqop_free(kqop);
+}
+
+/* signal handling */
+static int
+kq_sig_add(struct event_base *base, int nsignal, short old, short events, void *p)
+{
+ struct kqop *kqop = base->evbase;
+ struct kevent kev;
+ struct timespec timeout = { 0, 0 };
+ (void)p;
+
+ EVUTIL_ASSERT(nsignal >= 0 && nsignal < NSIG);
+
+ memset(&kev, 0, sizeof(kev));
+ kev.ident = nsignal;
+ kev.filter = EVFILT_SIGNAL;
+ kev.flags = EV_ADD;
+
+ /* 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);
+
+ /* We can set the handler for most signals to SIG_IGN and
+ * still have them reported to us in the queue. However,
+ * if the handler for SIGCHLD is SIG_IGN, the system reaps
+ * zombie processes for us, and we don't get any notification.
+ * This appears to be the only signal with this quirk. */
+ if (evsig_set_handler_(base, nsignal,
+ nsignal == SIGCHLD ? SIG_DFL : SIG_IGN) == -1)
+ return (-1);
+
+ return (0);
+}
+
+static int
+kq_sig_del(struct event_base *base, int nsignal, short old, short events, void *p)
+{
+ struct kqop *kqop = base->evbase;
+ struct kevent kev;
+
+ struct timespec timeout = { 0, 0 };
+ (void)p;
+
+ EVUTIL_ASSERT(nsignal >= 0 && nsignal < NSIG);
+
+ 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 (evsig_restore_handler_(base, nsignal) == -1)
+ return (-1);
+
+ return (0);
+}
+
+
+/* OSX 10.6 and FreeBSD 8.1 add support for EVFILT_USER, which we can use
+ * to wake up the event loop from another thread. */
+
+/* Magic number we use for our filter ID. */
+#define NOTIFY_IDENT 42
+
+int
+event_kq_add_notify_event_(struct event_base *base)
+{
+ struct kqop *kqop = base->evbase;
+#if defined(EVFILT_USER) && defined(NOTE_TRIGGER)
+ struct kevent kev;
+ struct timespec timeout = { 0, 0 };
+#endif
+
+ if (kqop->notify_event_added)
+ return 0;
+
+#if defined(EVFILT_USER) && defined(NOTE_TRIGGER)
+ memset(&kev, 0, sizeof(kev));
+ kev.ident = NOTIFY_IDENT;
+ kev.filter = EVFILT_USER;
+ kev.flags = EV_ADD | EV_CLEAR;
+
+ if (kevent(kqop->kq, &kev, 1, NULL, 0, &timeout) == -1) {
+ event_warn("kevent: adding EVFILT_USER event");
+ return -1;
+ }
+
+ kqop->notify_event_added = 1;
+
+ return 0;
+#else
+ return -1;
+#endif
+}
+
+int
+event_kq_notify_base_(struct event_base *base)
+{
+ struct kqop *kqop = base->evbase;
+#if defined(EVFILT_USER) && defined(NOTE_TRIGGER)
+ struct kevent kev;
+ struct timespec timeout = { 0, 0 };
+#endif
+ if (! kqop->notify_event_added)
+ return -1;
+
+#if defined(EVFILT_USER) && defined(NOTE_TRIGGER)
+ memset(&kev, 0, sizeof(kev));
+ kev.ident = NOTIFY_IDENT;
+ kev.filter = EVFILT_USER;
+ kev.fflags = NOTE_TRIGGER;
+
+ if (kevent(kqop->kq, &kev, 1, NULL, 0, &timeout) == -1) {
+ event_warn("kevent: triggering EVFILT_USER event");
+ return -1;
+ }
+
+ return 0;
+#else
+ return -1;
+#endif
+}
+
+#endif /* EVENT__HAVE_KQUEUE */
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