1 files changed, 333 insertions, 0 deletions
diff --git a/libevent-2.0.20-stable/poll.c b/libevent-2.0.20-stable/poll.c
new file mode 100644
index 0000000..04d311b
--- /dev/null
+++ b/libevent-2.0.20-stable/poll.c
@@ -0,0 +1,333 @@
+/*	$OpenBSD: poll.c,v 1.2 2002/06/25 15:50:15 mickey 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 <sys/types.h>
+#ifdef _EVENT_HAVE_SYS_TIME_H
+#include <sys/time.h>
+#endif
+#include <sys/queue.h>
+#include <poll.h>
+#include <signal.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+
+#include "event-internal.h"
+#include "evsignal-internal.h"
+#include "log-internal.h"
+#include "evmap-internal.h"
+#include "event2/thread.h"
+#include "evthread-internal.h"
+
+struct pollidx {
+	int idxplus1;
+};
+
+struct pollop {
+	int event_count;		/* Highest number alloc */
+	int nfds;			/* Highest number used */
+	int realloc_copy;		/* True iff we must realloc
+					 * event_set_copy */
+	struct pollfd *event_set;
+	struct pollfd *event_set_copy;
+};
+
+static void *poll_init(struct event_base *);
+static int poll_add(struct event_base *, int, short old, short events, void *_idx);
+static int poll_del(struct event_base *, int, short old, short events, void *_idx);
+static int poll_dispatch(struct event_base *, struct timeval *);
+static void poll_dealloc(struct event_base *);
+
+const struct eventop pollops = {
+	"poll",
+	poll_init,
+	poll_add,
+	poll_del,
+	poll_dispatch,
+	poll_dealloc,
+	0, /* doesn't need_reinit */
+	EV_FEATURE_FDS,
+	sizeof(struct pollidx),
+};
+
+static void *
+poll_init(struct event_base *base)
+{
+	struct pollop *pollop;
+
+	if (!(pollop = mm_calloc(1, sizeof(struct pollop))))
+		return (NULL);
+
+	evsig_init(base);
+
+	return (pollop);
+}
+
+#ifdef CHECK_INVARIANTS
+static void
+poll_check_ok(struct pollop *pop)
+{
+	int i, idx;
+	struct event *ev;
+
+	for (i = 0; i < pop->fd_count; ++i) {
+		idx = pop->idxplus1_by_fd[i]-1;
+		if (idx < 0)
+			continue;
+		EVUTIL_ASSERT(pop->event_set[idx].fd == i);
+	}
+	for (i = 0; i < pop->nfds; ++i) {
+		struct pollfd *pfd = &pop->event_set[i];
+		EVUTIL_ASSERT(pop->idxplus1_by_fd[pfd->fd] == i+1);
+	}
+}
+#else
+#define poll_check_ok(pop)
+#endif
+
+static int
+poll_dispatch(struct event_base *base, struct timeval *tv)
+{
+	int res, i, j, nfds;
+	long msec = -1;
+	struct pollop *pop = base->evbase;
+	struct pollfd *event_set;
+
+	poll_check_ok(pop);
+
+	nfds = pop->nfds;
+
+#ifndef _EVENT_DISABLE_THREAD_SUPPORT
+	if (base->th_base_lock) {
+		/* If we're using this backend in a multithreaded setting,
+		 * then we need to work on a copy of event_set, so that we can
+		 * let other threads modify the main event_set while we're
+		 * polling. If we're not multithreaded, then we'll skip the
+		 * copy step here to save memory and time. */
+		if (pop->realloc_copy) {
+			struct pollfd *tmp = mm_realloc(pop->event_set_copy,
+			    pop->event_count * sizeof(struct pollfd));
+			if (tmp == NULL) {
+				event_warn("realloc");
+				return -1;
+			}
+			pop->event_set_copy = tmp;
+			pop->realloc_copy = 0;
+		}
+		memcpy(pop->event_set_copy, pop->event_set,
+		    sizeof(struct pollfd)*nfds);
+		event_set = pop->event_set_copy;
+	} else {
+		event_set = pop->event_set;
+	}
+#else
+	event_set = pop->event_set;
+#endif
+
+	if (tv != NULL) {
+		msec = evutil_tv_to_msec(tv);
+		if (msec < 0 || msec > INT_MAX)
+			msec = INT_MAX;
+	}
+
+	EVBASE_RELEASE_LOCK(base, th_base_lock);
+
+	res = poll(event_set, nfds, msec);
+
+	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
+
+	if (res == -1) {
+		if (errno != EINTR) {
+			event_warn("poll");
+			return (-1);
+		}
+
+		return (0);
+	}
+
+	event_debug(("%s: poll reports %d", __func__, res));
+
+	if (res == 0 || nfds == 0)
+		return (0);
+
+	i = random() % nfds;
+	for (j = 0; j < nfds; j++) {
+		int what;
+		if (++i == nfds)
+			i = 0;
+		what = event_set[i].revents;
+		if (!what)
+			continue;
+
+		res = 0;
+
+		/* If the file gets closed notify */
+		if (what & (POLLHUP|POLLERR))
+			what |= POLLIN|POLLOUT;
+		if (what & POLLIN)
+			res |= EV_READ;
+		if (what & POLLOUT)
+			res |= EV_WRITE;
+		if (res == 0)
+			continue;
+
+		evmap_io_active(base, event_set[i].fd, res);
+	}
+
+	return (0);
+}
+
+static int
+poll_add(struct event_base *base, int fd, short old, short events, void *_idx)
+{
+	struct pollop *pop = base->evbase;
+	struct pollfd *pfd = NULL;
+	struct pollidx *idx = _idx;
+	int i;
+
+	EVUTIL_ASSERT((events & EV_SIGNAL) == 0);
+	if (!(events & (EV_READ|EV_WRITE)))
+		return (0);
+
+	poll_check_ok(pop);
+	if (pop->nfds + 1 >= pop->event_count) {
+		struct pollfd *tmp_event_set;
+		int tmp_event_count;
+
+		if (pop->event_count < 32)
+			tmp_event_count = 32;
+		else
+			tmp_event_count = pop->event_count * 2;
+
+		/* We need more file descriptors */
+		tmp_event_set = mm_realloc(pop->event_set,
+				 tmp_event_count * sizeof(struct pollfd));
+		if (tmp_event_set == NULL) {
+			event_warn("realloc");
+			return (-1);
+		}
+		pop->event_set = tmp_event_set;
+
+		pop->event_count = tmp_event_count;
+		pop->realloc_copy = 1;
+	}
+
+	i = idx->idxplus1 - 1;
+
+	if (i >= 0) {
+		pfd = &pop->event_set[i];
+	} else {
+		i = pop->nfds++;
+		pfd = &pop->event_set[i];
+		pfd->events = 0;
+		pfd->fd = fd;
+		idx->idxplus1 = i + 1;
+	}
+
+	pfd->revents = 0;
+	if (events & EV_WRITE)
+		pfd->events |= POLLOUT;
+	if (events & EV_READ)
+		pfd->events |= POLLIN;
+	poll_check_ok(pop);
+
+	return (0);
+}
+
+/*
+ * Nothing to be done here.
+ */
+
+static int
+poll_del(struct event_base *base, int fd, short old, short events, void *_idx)
+{
+	struct pollop *pop = base->evbase;
+	struct pollfd *pfd = NULL;
+	struct pollidx *idx = _idx;
+	int i;
+
+	EVUTIL_ASSERT((events & EV_SIGNAL) == 0);
+	if (!(events & (EV_READ|EV_WRITE)))
+		return (0);
+
+	poll_check_ok(pop);
+	i = idx->idxplus1 - 1;
+	if (i < 0)
+		return (-1);
+
+	/* Do we still want to read or write? */
+	pfd = &pop->event_set[i];
+	if (events & EV_READ)
+		pfd->events &= ~POLLIN;
+	if (events & EV_WRITE)
+		pfd->events &= ~POLLOUT;
+	poll_check_ok(pop);
+	if (pfd->events)
+		/* Another event cares about that fd. */
+		return (0);
+
+	/* Okay, so we aren't interested in that fd anymore. */
+	idx->idxplus1 = 0;
+
+	--pop->nfds;
+	if (i != pop->nfds) {
+		/*
+		 * Shift the last pollfd down into the now-unoccupied
+		 * position.
+		 */
+		memcpy(&pop->event_set[i], &pop->event_set[pop->nfds],
+		       sizeof(struct pollfd));
+		idx = evmap_io_get_fdinfo(&base->io, pop->event_set[i].fd);
+		EVUTIL_ASSERT(idx);
+		EVUTIL_ASSERT(idx->idxplus1 == pop->nfds + 1);
+		idx->idxplus1 = i + 1;
+	}
+
+	poll_check_ok(pop);
+	return (0);
+}
+
+static void
+poll_dealloc(struct event_base *base)
+{
+	struct pollop *pop = base->evbase;
+
+	evsig_dealloc(base);
+	if (pop->event_set)
+		mm_free(pop->event_set);
+	if (pop->event_set_copy)
+		mm_free(pop->event_set_copy);
+
+	memset(pop, 0, sizeof(struct pollop));
+	mm_free(pop);
+}