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diff --git a/libs/libevent/docs/evport.c b/libs/libevent/docs/evport.c
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+/*
+ * Submitted by David Pacheco (dp.spambait@gmail.com)
+ *
+ * Copyright 2006-2007 Niels Provos
+ * 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 SUN MICROSYSTEMS, INC. ``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 SUN MICROSYSTEMS, INC. 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.
+ */
+
+/*
+ * Copyright (c) 2007 Sun Microsystems. All rights reserved.
+ * Use is subject to license terms.
+ */
+
+/*
+ * evport.c: event backend using Solaris 10 event ports. See port_create(3C).
+ * This implementation is loosely modeled after the one used for select(2) (in
+ * select.c).
+ *
+ * The outstanding events are tracked in a data structure called evport_data.
+ * Each entry in the ed_fds array corresponds to a file descriptor, and contains
+ * pointers to the read and write events that correspond to that fd. (That is,
+ * when the file is readable, the "read" event should handle it, etc.)
+ *
+ * evport_add and evport_del update this data structure. evport_dispatch uses it
+ * to determine where to callback when an event occurs (which it gets from
+ * port_getn).
+ *
+ * Helper functions are used: grow() grows the file descriptor array as
+ * necessary when large fd's come in. reassociate() takes care of maintaining
+ * the proper file-descriptor/event-port associations.
+ *
+ * As in the select(2) implementation, signals are handled by evsignal.
+ */
+
+#include "event2/event-config.h"
+#include "evconfig-private.h"
+
+#ifdef EVENT__HAVE_EVENT_PORTS
+
+#include <sys/time.h>
+#include <sys/queue.h>
+#include <errno.h>
+#include <poll.h>
+#include <port.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+#include <unistd.h>
+
+#include "event2/thread.h"
+
+#include "evthread-internal.h"
+#include "event-internal.h"
+#include "log-internal.h"
+#include "evsignal-internal.h"
+#include "evmap-internal.h"
+
+#define INITIAL_EVENTS_PER_GETN 8
+#define MAX_EVENTS_PER_GETN 4096
+
+/*
+ * Per-file-descriptor information about what events we're subscribed to. These
+ * fields are NULL if no event is subscribed to either of them.
+ */
+
+struct fd_info {
+	/* combinations of EV_READ and EV_WRITE */
+	short fdi_what;
+	/* Index of this fd within ed_pending, plus 1.  Zero if this fd is
+	 * not in ed_pending.  (The +1 is a hack so that memset(0) will set
+	 * it to a nil index. */
+	int pending_idx_plus_1;
+};
+
+#define FDI_HAS_READ(fdi)  ((fdi)->fdi_what & EV_READ)
+#define FDI_HAS_WRITE(fdi) ((fdi)->fdi_what & EV_WRITE)
+#define FDI_HAS_EVENTS(fdi) (FDI_HAS_READ(fdi) || FDI_HAS_WRITE(fdi))
+#define FDI_TO_SYSEVENTS(fdi) (FDI_HAS_READ(fdi) ? POLLIN : 0) | \
+    (FDI_HAS_WRITE(fdi) ? POLLOUT : 0)
+
+struct evport_data {
+	int		ed_port;	/* event port for system events  */
+	/* How many elements of ed_pending should we look at? */
+	int ed_npending;
+	/* How many elements are allocated in ed_pending and pevtlist? */
+	int ed_maxevents;
+	/* fdi's that we need to reassoc */
+	int *ed_pending;
+	/* storage space for incoming events. */ 
+	port_event_t *ed_pevtlist;
+	
+};
+
+static void*	evport_init(struct event_base *);
+static int evport_add(struct event_base *, int fd, short old, short events, void *);
+static int evport_del(struct event_base *, int fd, short old, short events, void *);
+static int	evport_dispatch(struct event_base *, struct timeval *);
+static void	evport_dealloc(struct event_base *);
+static int	grow(struct evport_data *, int min_events);
+
+const struct eventop evportops = {
+	"evport",
+	evport_init,
+	evport_add,
+	evport_del,
+	evport_dispatch,
+	evport_dealloc,
+	1, /* need reinit */
+	0, /* features */
+	sizeof(struct fd_info), /* fdinfo length */
+};
+
+/*
+ * Initialize the event port implementation.
+ */
+
+static void*
+evport_init(struct event_base *base)
+{
+	struct evport_data *evpd;
+
+	if (!(evpd = mm_calloc(1, sizeof(struct evport_data))))
+		return (NULL);
+
+	if ((evpd->ed_port = port_create()) == -1) {
+		mm_free(evpd);
+		return (NULL);
+	}
+
+	if (grow(evpd, INITIAL_EVENTS_PER_GETN) < 0) {
+		close(evpd->ed_port);
+		mm_free(evpd);
+		return NULL;
+	}
+		
+	evpd->ed_npending = 0;
+
+	evsig_init_(base);
+
+	return (evpd);
+}
+
+static int
+grow(struct evport_data *data, int min_events)
+{
+	int newsize;
+	int *new_pending;
+	port_event_t *new_pevtlist;
+	if (data->ed_maxevents) {
+		newsize = data->ed_maxevents;
+		do {
+			newsize *= 2;
+		} while (newsize < min_events);
+	} else {
+		newsize = min_events;
+	}
+
+	new_pending = mm_realloc(data->ed_pending, sizeof(int)*newsize);
+	if (new_pending == NULL)
+		return -1;
+	data->ed_pending = new_pending;
+	new_pevtlist = mm_realloc(data->ed_pevtlist, sizeof(port_event_t)*newsize);
+	if (new_pevtlist == NULL)
+		return -1;
+	data->ed_pevtlist = new_pevtlist; 
+
+	data->ed_maxevents = newsize;
+	return 0;
+}
+
+#ifdef CHECK_INVARIANTS
+/*
+ * Checks some basic properties about the evport_data structure. Because it
+ * checks all file descriptors, this function can be expensive when the maximum
+ * file descriptor ever used is rather large.
+ */
+
+static void
+check_evportop(struct evport_data *evpd)
+{
+	EVUTIL_ASSERT(evpd);
+	EVUTIL_ASSERT(evpd->ed_port > 0);
+}
+
+/*
+ * Verifies very basic integrity of a given port_event.
+ */
+static void
+check_event(port_event_t* pevt)
+{
+	/*
+	 * We've only registered for PORT_SOURCE_FD events. The only
+	 * other thing we can legitimately receive is PORT_SOURCE_ALERT,
+	 * but since we're not using port_alert either, we can assume
+	 * PORT_SOURCE_FD.
+	 */
+	EVUTIL_ASSERT(pevt->portev_source == PORT_SOURCE_FD);
+}
+
+#else
+#define check_evportop(epop)
+#define check_event(pevt)
+#endif /* CHECK_INVARIANTS */
+
+/*
+ * (Re)associates the given file descriptor with the event port. The OS events
+ * are specified (implicitly) from the fd_info struct.
+ */
+static int
+reassociate(struct evport_data *epdp, struct fd_info *fdip, int fd)
+{
+	int sysevents = FDI_TO_SYSEVENTS(fdip);
+
+	if (sysevents != 0) {
+		if (port_associate(epdp->ed_port, PORT_SOURCE_FD,
+				   fd, sysevents, fdip) == -1) {
+			event_warn("port_associate");
+			return (-1);
+		}
+	}
+
+	check_evportop(epdp);
+
+	return (0);
+}
+
+/*
+ * Main event loop - polls port_getn for some number of events, and processes
+ * them.
+ */
+
+static int
+evport_dispatch(struct event_base *base, struct timeval *tv)
+{
+	int i, res;
+	struct evport_data *epdp = base->evbase;
+	port_event_t *pevtlist = epdp->ed_pevtlist;
+
+	/*
+	 * port_getn will block until it has at least nevents events. It will
+	 * also return how many it's given us (which may be more than we asked
+	 * for, as long as it's less than our maximum (ed_maxevents)) in
+	 * nevents.
+	 */
+	int nevents = 1;
+
+	/*
+	 * We have to convert a struct timeval to a struct timespec
+	 * (only difference is nanoseconds vs. microseconds). If no time-based
+	 * events are active, we should wait for I/O (and tv == NULL).
+	 */
+	struct timespec ts;
+	struct timespec *ts_p = NULL;
+	if (tv != NULL) {
+		ts.tv_sec = tv->tv_sec;
+		ts.tv_nsec = tv->tv_usec * 1000;
+		ts_p = &ts;
+	}
+
+	/*
+	 * Before doing anything else, we need to reassociate the events we hit
+	 * last time which need reassociation. See comment at the end of the
+	 * loop below.
+	 */
+	for (i = 0; i < epdp->ed_npending; ++i) {
+		struct fd_info *fdi = NULL;
+		const int fd = epdp->ed_pending[i];
+		if (fd != -1) {
+			/* We might have cleared out this event; we need
+			 * to be sure that it's still set. */
+			fdi = evmap_io_get_fdinfo_(&base->io, fd);
+		}
+
+		if (fdi != NULL && FDI_HAS_EVENTS(fdi)) {
+			reassociate(epdp, fdi, fd);
+			/* epdp->ed_pending[i] = -1; */
+			fdi->pending_idx_plus_1 = 0;
+		}
+	}
+
+	EVBASE_RELEASE_LOCK(base, th_base_lock);
+
+	res = port_getn(epdp->ed_port, pevtlist, epdp->ed_maxevents,
+	    (unsigned int *) &nevents, ts_p);
+
+	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
+
+	if (res == -1) {
+		if (errno == EINTR || errno == EAGAIN) {
+			return (0);
+		} else if (errno == ETIME) {
+			if (nevents == 0)
+				return (0);
+		} else {
+			event_warn("port_getn");
+			return (-1);
+		}
+	}
+
+	event_debug(("%s: port_getn reports %d events", __func__, nevents));
+
+	for (i = 0; i < nevents; ++i) {
+		port_event_t *pevt = &pevtlist[i];
+		int fd = (int) pevt->portev_object;
+		struct fd_info *fdi = pevt->portev_user;
+		/*EVUTIL_ASSERT(evmap_io_get_fdinfo_(&base->io, fd) == fdi);*/
+
+		check_evportop(epdp);
+		check_event(pevt);
+		epdp->ed_pending[i] = fd;
+		fdi->pending_idx_plus_1 = i + 1;
+
+		/*
+		 * Figure out what kind of event it was
+		 * (because we have to pass this to the callback)
+		 */
+		res = 0;
+		if (pevt->portev_events & (POLLERR|POLLHUP)) {
+			res = EV_READ | EV_WRITE;
+		} else {
+			if (pevt->portev_events & POLLIN)
+				res |= EV_READ;
+			if (pevt->portev_events & POLLOUT)
+				res |= EV_WRITE;
+		}
+
+		/*
+		 * Check for the error situations or a hangup situation
+		 */
+		if (pevt->portev_events & (POLLERR|POLLHUP|POLLNVAL))
+			res |= EV_READ|EV_WRITE;
+
+		evmap_io_active_(base, fd, res);
+	} /* end of all events gotten */
+	epdp->ed_npending = nevents;
+
+	if (nevents == epdp->ed_maxevents &&
+	    epdp->ed_maxevents < MAX_EVENTS_PER_GETN) {
+		/* we used all the space this time.  We should be ready
+		 * for more events next time around. */
+		grow(epdp, epdp->ed_maxevents * 2);
+	}
+
+	check_evportop(epdp);
+
+	return (0);
+}
+
+
+/*
+ * Adds the given event (so that you will be notified when it happens via
+ * the callback function).
+ */
+
+static int
+evport_add(struct event_base *base, int fd, short old, short events, void *p)
+{
+	struct evport_data *evpd = base->evbase;
+	struct fd_info *fdi = p;
+
+	check_evportop(evpd);
+
+	fdi->fdi_what |= events;
+
+	return reassociate(evpd, fdi, fd);
+}
+
+/*
+ * Removes the given event from the list of events to wait for.
+ */
+
+static int
+evport_del(struct event_base *base, int fd, short old, short events, void *p)
+{
+	struct evport_data *evpd = base->evbase;
+	struct fd_info *fdi = p;
+	int associated = ! fdi->pending_idx_plus_1;
+
+	check_evportop(evpd);
+
+	fdi->fdi_what &= ~(events &(EV_READ|EV_WRITE));
+
+	if (associated) {
+		if (!FDI_HAS_EVENTS(fdi) &&
+		    port_dissociate(evpd->ed_port, PORT_SOURCE_FD, fd) == -1) {
+			/*
+			 * Ignore EBADFD error the fd could have been closed
+			 * before event_del() was called.
+			 */
+			if (errno != EBADFD) {
+				event_warn("port_dissociate");
+				return (-1);
+			}
+		} else {
+			if (FDI_HAS_EVENTS(fdi)) {
+				return (reassociate(evpd, fdi, fd));
+			}
+		}
+	} else {
+		if ((fdi->fdi_what & (EV_READ|EV_WRITE)) == 0) {
+			const int i = fdi->pending_idx_plus_1 - 1;
+			EVUTIL_ASSERT(evpd->ed_pending[i] == fd);
+			evpd->ed_pending[i] = -1;
+			fdi->pending_idx_plus_1 = 0;
+		}
+	}
+	return 0;
+}
+
+
+static void
+evport_dealloc(struct event_base *base)
+{
+	struct evport_data *evpd = base->evbase;
+
+	evsig_dealloc_(base);
+
+	close(evpd->ed_port);
+
+	if (evpd->ed_pending)
+		mm_free(evpd->ed_pending);
+	if (evpd->ed_pevtlist)
+		mm_free(evpd->ed_pevtlist);
+
+	mm_free(evpd);
+}
+
+#endif /* EVENT__HAVE_EVENT_PORTS */