| /* $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 STARBOARD |
| #include "libevent-starboard.h" |
| |
| #include <poll.h> |
| #include <stdlib.h> |
| |
| // Use libevent's local compatibility versions of these. |
| #include "third_party/libevent/compat/sys/queue.h" |
| #include "third_party/libevent/compat/sys/_libevent_time.h" |
| |
| // Include Starboard poems after all system headers. |
| #include "starboard/client_porting/poem/stdio_poem.h" |
| #include "starboard/client_porting/poem/string_poem.h" |
| #else // STARBOARD |
| #include <sys/types.h> |
| #ifdef HAVE_SYS_TIME_H |
| #include <sys/time.h> |
| #else |
| #include <sys/_libevent_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 |
| #endif // STARBOARD |
| |
| #include "event.h" |
| #include "event-internal.h" |
| #ifndef STARBOARD |
| #include "evsignal.h" |
| #endif // STARBOARD |
| #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 (evutil_getenv("EVENT_NOPOLL")) |
| return (NULL); |
| |
| if (!(pollop = calloc(1, sizeof(struct pollop)))) |
| return (NULL); |
| |
| #ifndef STARBOARD |
| evsignal_init(base); |
| #endif |
| |
| 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, j, 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); |
| } |
| |
| #ifndef STARBOARD |
| evsignal_process(base); |
| #endif |
| return (0); |
| } |
| #ifndef STARBOARD |
| } else if (base->sig.evsignal_caught) { |
| evsignal_process(base); |
| } |
| #endif |
| |
| event_debug(("%s: poll reports %d", __func__, res)); |
| |
| if (res == 0 || nfds == 0) |
| return (0); |
| |
| i = random() % nfds; |
| for (j = 0; j < nfds; j++) { |
| struct event *r_ev = NULL, *w_ev = NULL; |
| int what; |
| if (++i == nfds) |
| i = 0; |
| what = pop->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; |
| 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; |
| |
| #ifndef STARBOARD |
| if (ev->ev_events & EV_SIGNAL) |
| return (evsignal_add(ev)); |
| #endif |
| 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; |
| |
| #ifndef STARBOARD |
| if (ev->ev_events & EV_SIGNAL) |
| return (evsignal_del(ev)); |
| #endif |
| |
| 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; |
| |
| #ifndef STARBOARD |
| evsignal_dealloc(base); |
| #endif |
| |
| 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); |
| } |