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-rw-r--r--extra/libevent/poll.c378
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diff --git a/extra/libevent/poll.c b/extra/libevent/poll.c
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+/* $OpenBSD: poll.c,v 1.2 2002/06/25 15:50:15 mickey Exp $ */
+
+/*
+ * Copyright 2000-2003 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
+
+#ifdef HAVE_POLL
+
+#include <sys/types.h>
+#ifdef HAVE_SYS_TIME_H
+#include <sys/time.h>
+#else
+#include <sys/_time.h>
+#endif
+#include <sys/queue.h>
+#include <poll.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+#ifdef CHECK_INVARIANTS
+#include <assert.h>
+#endif
+
+#include "event.h"
+#include "event-internal.h"
+#include "evsignal.h"
+#include "log.h"
+
+struct pollop {
+ int event_count; /* Highest number alloc */
+ int nfds; /* Size of event_* */
+ int fd_count; /* Size of idxplus1_by_fd */
+ struct pollfd *event_set;
+ struct event **event_r_back;
+ struct event **event_w_back;
+ int *idxplus1_by_fd; /* Index into event_set by fd; we add 1 so
+ * that 0 (which is easy to memset) can mean
+ * "no entry." */
+};
+
+static void *poll_init (struct event_base *);
+static int poll_add (void *, struct event *);
+static int poll_del (void *, struct event *);
+static int poll_dispatch (struct event_base *, void *, struct timeval *);
+static void poll_dealloc (struct event_base *, void *);
+
+const struct eventop pollops = {
+ "poll",
+ poll_init,
+ poll_add,
+ poll_del,
+ poll_dispatch,
+ poll_dealloc,
+ 0
+};
+
+static void *
+poll_init(struct event_base *base)
+{
+ struct pollop *pollop;
+
+ /* Disable poll when this environment variable is set */
+ if (getenv("EVENT_NOPOLL"))
+ return (NULL);
+
+ if (!(pollop = calloc(1, sizeof(struct pollop))))
+ return (NULL);
+
+ evsignal_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;
+ assert(pop->event_set[idx].fd == i);
+ if (pop->event_set[idx].events & POLLIN) {
+ ev = pop->event_r_back[idx];
+ assert(ev);
+ assert(ev->ev_events & EV_READ);
+ assert(ev->ev_fd == i);
+ }
+ if (pop->event_set[idx].events & POLLOUT) {
+ ev = pop->event_w_back[idx];
+ assert(ev);
+ assert(ev->ev_events & EV_WRITE);
+ assert(ev->ev_fd == i);
+ }
+ }
+ for (i = 0; i < pop->nfds; ++i) {
+ struct pollfd *pfd = &pop->event_set[i];
+ assert(pop->idxplus1_by_fd[pfd->fd] == i+1);
+ }
+}
+#else
+#define poll_check_ok(pop)
+#endif
+
+static int
+poll_dispatch(struct event_base *base, void *arg, struct timeval *tv)
+{
+ int res, i, msec = -1, nfds;
+ struct pollop *pop = arg;
+
+ poll_check_ok(pop);
+
+ if (tv != NULL)
+ msec = tv->tv_sec * 1000 + (tv->tv_usec + 999) / 1000;
+
+ nfds = pop->nfds;
+ res = poll(pop->event_set, nfds, msec);
+
+ if (res == -1) {
+ if (errno != EINTR) {
+ event_warn("poll");
+ return (-1);
+ }
+
+ evsignal_process(base);
+ return (0);
+ } else if (base->sig.evsignal_caught) {
+ evsignal_process(base);
+ }
+
+ event_debug(("%s: poll reports %d", __func__, res));
+
+ if (res == 0)
+ return (0);
+
+ for (i = 0; i < nfds; i++) {
+ int what = pop->event_set[i].revents;
+ struct event *r_ev = NULL, *w_ev = NULL;
+ if (!what)
+ continue;
+
+ res = 0;
+
+ /* If the file gets closed notify */
+ if (what & (POLLHUP|POLLERR))
+ what |= POLLIN|POLLOUT;
+ if (what & POLLIN) {
+ res |= EV_READ;
+ r_ev = pop->event_r_back[i];
+ }
+ if (what & POLLOUT) {
+ res |= EV_WRITE;
+ w_ev = pop->event_w_back[i];
+ }
+ if (res == 0)
+ continue;
+
+ if (r_ev && (res & r_ev->ev_events)) {
+ event_active(r_ev, res & r_ev->ev_events, 1);
+ }
+ if (w_ev && w_ev != r_ev && (res & w_ev->ev_events)) {
+ event_active(w_ev, res & w_ev->ev_events, 1);
+ }
+ }
+
+ return (0);
+}
+
+static int
+poll_add(void *arg, struct event *ev)
+{
+ struct pollop *pop = arg;
+ struct pollfd *pfd = NULL;
+ int i;
+
+ if (ev->ev_events & EV_SIGNAL)
+ return (evsignal_add(ev));
+ if (!(ev->ev_events & (EV_READ|EV_WRITE)))
+ return (0);
+
+ poll_check_ok(pop);
+ if (pop->nfds + 1 >= pop->event_count) {
+ struct pollfd *tmp_event_set;
+ struct event **tmp_event_r_back;
+ struct event **tmp_event_w_back;
+ 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 = 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;
+
+ tmp_event_r_back = realloc(pop->event_r_back,
+ tmp_event_count * sizeof(struct event *));
+ if (tmp_event_r_back == NULL) {
+ /* event_set overallocated; that's okay. */
+ event_warn("realloc");
+ return (-1);
+ }
+ pop->event_r_back = tmp_event_r_back;
+
+ tmp_event_w_back = realloc(pop->event_w_back,
+ tmp_event_count * sizeof(struct event *));
+ if (tmp_event_w_back == NULL) {
+ /* event_set and event_r_back overallocated; that's
+ * okay. */
+ event_warn("realloc");
+ return (-1);
+ }
+ pop->event_w_back = tmp_event_w_back;
+
+ pop->event_count = tmp_event_count;
+ }
+ if (ev->ev_fd >= pop->fd_count) {
+ int *tmp_idxplus1_by_fd;
+ int new_count;
+ if (pop->fd_count < 32)
+ new_count = 32;
+ else
+ new_count = pop->fd_count * 2;
+ while (new_count <= ev->ev_fd)
+ new_count *= 2;
+ tmp_idxplus1_by_fd =
+ realloc(pop->idxplus1_by_fd, new_count * sizeof(int));
+ if (tmp_idxplus1_by_fd == NULL) {
+ event_warn("realloc");
+ return (-1);
+ }
+ pop->idxplus1_by_fd = tmp_idxplus1_by_fd;
+ memset(pop->idxplus1_by_fd + pop->fd_count,
+ 0, sizeof(int)*(new_count - pop->fd_count));
+ pop->fd_count = new_count;
+ }
+
+ i = pop->idxplus1_by_fd[ev->ev_fd] - 1;
+ if (i >= 0) {
+ pfd = &pop->event_set[i];
+ } else {
+ i = pop->nfds++;
+ pfd = &pop->event_set[i];
+ pfd->events = 0;
+ pfd->fd = ev->ev_fd;
+ pop->event_w_back[i] = pop->event_r_back[i] = NULL;
+ pop->idxplus1_by_fd[ev->ev_fd] = i + 1;
+ }
+
+ pfd->revents = 0;
+ if (ev->ev_events & EV_WRITE) {
+ pfd->events |= POLLOUT;
+ pop->event_w_back[i] = ev;
+ }
+ if (ev->ev_events & EV_READ) {
+ pfd->events |= POLLIN;
+ pop->event_r_back[i] = ev;
+ }
+ poll_check_ok(pop);
+
+ return (0);
+}
+
+/*
+ * Nothing to be done here.
+ */
+
+static int
+poll_del(void *arg, struct event *ev)
+{
+ struct pollop *pop = arg;
+ struct pollfd *pfd = NULL;
+ int i;
+
+ if (ev->ev_events & EV_SIGNAL)
+ return (evsignal_del(ev));
+
+ if (!(ev->ev_events & (EV_READ|EV_WRITE)))
+ return (0);
+
+ poll_check_ok(pop);
+ i = pop->idxplus1_by_fd[ev->ev_fd] - 1;
+ if (i < 0)
+ return (-1);
+
+ /* Do we still want to read or write? */
+ pfd = &pop->event_set[i];
+ if (ev->ev_events & EV_READ) {
+ pfd->events &= ~POLLIN;
+ pop->event_r_back[i] = NULL;
+ }
+ if (ev->ev_events & EV_WRITE) {
+ pfd->events &= ~POLLOUT;
+ pop->event_w_back[i] = NULL;
+ }
+ 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. */
+ pop->idxplus1_by_fd[ev->ev_fd] = 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));
+ pop->event_r_back[i] = pop->event_r_back[pop->nfds];
+ pop->event_w_back[i] = pop->event_w_back[pop->nfds];
+ pop->idxplus1_by_fd[pop->event_set[i].fd] = i + 1;
+ }
+
+ poll_check_ok(pop);
+ return (0);
+}
+
+static void
+poll_dealloc(struct event_base *base, void *arg)
+{
+ struct pollop *pop = arg;
+
+ evsignal_dealloc(base);
+ if (pop->event_set)
+ free(pop->event_set);
+ if (pop->event_r_back)
+ free(pop->event_r_back);
+ if (pop->event_w_back)
+ free(pop->event_w_back);
+ if (pop->idxplus1_by_fd)
+ free(pop->idxplus1_by_fd);
+
+ memset(pop, 0, sizeof(struct pollop));
+ free(pop);
+}
+
+#endif /* HAVE_POLL */