diff options
Diffstat (limited to 'libs/tgl/libevent/epoll.c')
-rw-r--r-- | libs/tgl/libevent/epoll.c | 540 |
1 files changed, 0 insertions, 540 deletions
diff --git a/libs/tgl/libevent/epoll.c b/libs/tgl/libevent/epoll.c deleted file mode 100644 index bf730b23db..0000000000 --- a/libs/tgl/libevent/epoll.c +++ /dev/null @@ -1,540 +0,0 @@ -/* - * Copyright 2000-2007 Niels Provos <provos@citi.umich.edu> - * Copyright 2007-2012 Niels Provos, 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_EPOLL - -#include <stdint.h> -#include <sys/types.h> -#include <sys/resource.h> -#ifdef EVENT__HAVE_SYS_TIME_H -#include <sys/time.h> -#endif -#include <sys/queue.h> -#include <sys/epoll.h> -#include <signal.h> -#include <limits.h> -#include <stdio.h> -#include <stdlib.h> -#include <string.h> -#include <unistd.h> -#include <errno.h> -#ifdef EVENT__HAVE_FCNTL_H -#include <fcntl.h> -#endif -#ifdef EVENT__HAVE_SYS_TIMERFD_H -#include <sys/timerfd.h> -#endif - -#include "event-internal.h" -#include "evsignal-internal.h" -#include "event2/thread.h" -#include "evthread-internal.h" -#include "log-internal.h" -#include "evmap-internal.h" -#include "changelist-internal.h" -#include "time-internal.h" - -/* Since Linux 2.6.17, epoll is able to report about peer half-closed connection - using special EPOLLRDHUP flag on a read event. -*/ -#if !defined(EPOLLRDHUP) -#define EPOLLRDHUP 0 -#define EARLY_CLOSE_IF_HAVE_RDHUP 0 -#else -#define EARLY_CLOSE_IF_HAVE_RDHUP EV_FEATURE_EARLY_CLOSE -#endif - -#include "epolltable-internal.h" - -#if defined(EVENT__HAVE_SYS_TIMERFD_H) && \ - defined(EVENT__HAVE_TIMERFD_CREATE) && \ - defined(HAVE_POSIX_MONOTONIC) && defined(TFD_NONBLOCK) && \ - defined(TFD_CLOEXEC) -/* Note that we only use timerfd if TFD_NONBLOCK and TFD_CLOEXEC are available - and working. This means that we can't support it on 2.6.25 (where timerfd - was introduced) or 2.6.26, since 2.6.27 introduced those flags. - */ -#define USING_TIMERFD -#endif - -struct epollop { - struct epoll_event *events; - int nevents; - int epfd; -#ifdef USING_TIMERFD - int timerfd; -#endif -}; - -static void *epoll_init(struct event_base *); -static int epoll_dispatch(struct event_base *, struct timeval *); -static void epoll_dealloc(struct event_base *); - -static const struct eventop epollops_changelist = { - "epoll (with changelist)", - epoll_init, - event_changelist_add_, - event_changelist_del_, - epoll_dispatch, - epoll_dealloc, - 1, /* need reinit */ - EV_FEATURE_ET|EV_FEATURE_O1| EARLY_CLOSE_IF_HAVE_RDHUP, - EVENT_CHANGELIST_FDINFO_SIZE -}; - - -static int epoll_nochangelist_add(struct event_base *base, evutil_socket_t fd, - short old, short events, void *p); -static int epoll_nochangelist_del(struct event_base *base, evutil_socket_t fd, - short old, short events, void *p); - -const struct eventop epollops = { - "epoll", - epoll_init, - epoll_nochangelist_add, - epoll_nochangelist_del, - epoll_dispatch, - epoll_dealloc, - 1, /* need reinit */ - EV_FEATURE_ET|EV_FEATURE_O1|EV_FEATURE_EARLY_CLOSE, - 0 -}; - -#define INITIAL_NEVENT 32 -#define MAX_NEVENT 4096 - -/* On Linux kernels at least up to 2.6.24.4, epoll can't handle timeout - * values bigger than (LONG_MAX - 999ULL)/HZ. HZ in the wild can be - * as big as 1000, and LONG_MAX can be as small as (1<<31)-1, so the - * largest number of msec we can support here is 2147482. Let's - * round that down by 47 seconds. - */ -#define MAX_EPOLL_TIMEOUT_MSEC (35*60*1000) - -static void * -epoll_init(struct event_base *base) -{ - int epfd = -1; - struct epollop *epollop; - -#ifdef EVENT__HAVE_EPOLL_CREATE1 - /* First, try the shiny new epoll_create1 interface, if we have it. */ - epfd = epoll_create1(EPOLL_CLOEXEC); -#endif - if (epfd == -1) { - /* Initialize the kernel queue using the old interface. (The - size field is ignored since 2.6.8.) */ - if ((epfd = epoll_create(32000)) == -1) { - if (errno != ENOSYS) - event_warn("epoll_create"); - return (NULL); - } - evutil_make_socket_closeonexec(epfd); - } - - if (!(epollop = mm_calloc(1, sizeof(struct epollop)))) { - close(epfd); - return (NULL); - } - - epollop->epfd = epfd; - - /* Initialize fields */ - epollop->events = mm_calloc(INITIAL_NEVENT, sizeof(struct epoll_event)); - if (epollop->events == NULL) { - mm_free(epollop); - close(epfd); - return (NULL); - } - epollop->nevents = INITIAL_NEVENT; - - if ((base->flags & EVENT_BASE_FLAG_EPOLL_USE_CHANGELIST) != 0 || - ((base->flags & EVENT_BASE_FLAG_IGNORE_ENV) == 0 && - evutil_getenv_("EVENT_EPOLL_USE_CHANGELIST") != NULL)) { - - base->evsel = &epollops_changelist; - } - -#ifdef USING_TIMERFD - /* - The epoll interface ordinarily gives us one-millisecond precision, - so on Linux it makes perfect sense to use the CLOCK_MONOTONIC_COARSE - timer. But when the user has set the new PRECISE_TIMER flag for an - event_base, we can try to use timerfd to give them finer granularity. - */ - if ((base->flags & EVENT_BASE_FLAG_PRECISE_TIMER) && - base->monotonic_timer.monotonic_clock == CLOCK_MONOTONIC) { - int fd; - fd = epollop->timerfd = timerfd_create(CLOCK_MONOTONIC, TFD_NONBLOCK|TFD_CLOEXEC); - if (epollop->timerfd >= 0) { - struct epoll_event epev; - memset(&epev, 0, sizeof(epev)); - epev.data.fd = epollop->timerfd; - epev.events = EPOLLIN; - if (epoll_ctl(epollop->epfd, EPOLL_CTL_ADD, fd, &epev) < 0) { - event_warn("epoll_ctl(timerfd)"); - close(fd); - epollop->timerfd = -1; - } - } else { - if (errno != EINVAL && errno != ENOSYS) { - /* These errors probably mean that we were - * compiled with timerfd/TFD_* support, but - * we're running on a kernel that lacks those. - */ - event_warn("timerfd_create"); - } - epollop->timerfd = -1; - } - } else { - epollop->timerfd = -1; - } -#endif - - evsig_init_(base); - - return (epollop); -} - -static const char * -change_to_string(int change) -{ - change &= (EV_CHANGE_ADD|EV_CHANGE_DEL); - if (change == EV_CHANGE_ADD) { - return "add"; - } else if (change == EV_CHANGE_DEL) { - return "del"; - } else if (change == 0) { - return "none"; - } else { - return "???"; - } -} - -static const char * -epoll_op_to_string(int op) -{ - return op == EPOLL_CTL_ADD?"ADD": - op == EPOLL_CTL_DEL?"DEL": - op == EPOLL_CTL_MOD?"MOD": - "???"; -} - -#define PRINT_CHANGES(op, events, ch, status) \ - "Epoll %s(%d) on fd %d " status ". " \ - "Old events were %d; " \ - "read change was %d (%s); " \ - "write change was %d (%s); " \ - "close change was %d (%s)", \ - epoll_op_to_string(op), \ - events, \ - ch->fd, \ - ch->old_events, \ - ch->read_change, \ - change_to_string(ch->read_change), \ - ch->write_change, \ - change_to_string(ch->write_change), \ - ch->close_change, \ - change_to_string(ch->close_change) - -static int -epoll_apply_one_change(struct event_base *base, - struct epollop *epollop, - const struct event_change *ch) -{ - struct epoll_event epev; - int op, events = 0; - int idx; - - idx = EPOLL_OP_TABLE_INDEX(ch); - op = epoll_op_table[idx].op; - events = epoll_op_table[idx].events; - - if (!events) { - EVUTIL_ASSERT(op == 0); - return 0; - } - - if ((ch->read_change|ch->write_change) & EV_CHANGE_ET) - events |= EPOLLET; - - memset(&epev, 0, sizeof(epev)); - epev.data.fd = ch->fd; - epev.events = events; - if (epoll_ctl(epollop->epfd, op, ch->fd, &epev) == 0) { - event_debug((PRINT_CHANGES(op, epev.events, ch, "okay"))); - return 0; - } - - switch (op) { - case EPOLL_CTL_MOD: - if (errno == ENOENT) { - /* If a MOD operation fails with ENOENT, the - * fd was probably closed and re-opened. We - * should retry the operation as an ADD. - */ - if (epoll_ctl(epollop->epfd, EPOLL_CTL_ADD, ch->fd, &epev) == -1) { - event_warn("Epoll MOD(%d) on %d retried as ADD; that failed too", - (int)epev.events, ch->fd); - return -1; - } else { - event_debug(("Epoll MOD(%d) on %d retried as ADD; succeeded.", - (int)epev.events, - ch->fd)); - return 0; - } - } - break; - case EPOLL_CTL_ADD: - if (errno == EEXIST) { - /* If an ADD operation fails with EEXIST, - * either the operation was redundant (as with a - * precautionary add), or we ran into a fun - * kernel bug where using dup*() to duplicate the - * same file into the same fd gives you the same epitem - * rather than a fresh one. For the second case, - * we must retry with MOD. */ - if (epoll_ctl(epollop->epfd, EPOLL_CTL_MOD, ch->fd, &epev) == -1) { - event_warn("Epoll ADD(%d) on %d retried as MOD; that failed too", - (int)epev.events, ch->fd); - return -1; - } else { - event_debug(("Epoll ADD(%d) on %d retried as MOD; succeeded.", - (int)epev.events, - ch->fd)); - return 0; - } - } - break; - case EPOLL_CTL_DEL: - if (errno == ENOENT || errno == EBADF || errno == EPERM) { - /* If a delete fails with one of these errors, - * that's fine too: we closed the fd before we - * got around to calling epoll_dispatch. */ - event_debug(("Epoll DEL(%d) on fd %d gave %s: DEL was unnecessary.", - (int)epev.events, - ch->fd, - strerror(errno))); - return 0; - } - break; - default: - break; - } - - event_warn(PRINT_CHANGES(op, epev.events, ch, "failed")); - return -1; -} - -static int -epoll_apply_changes(struct event_base *base) -{ - struct event_changelist *changelist = &base->changelist; - struct epollop *epollop = base->evbase; - struct event_change *ch; - - int r = 0; - int i; - - for (i = 0; i < changelist->n_changes; ++i) { - ch = &changelist->changes[i]; - if (epoll_apply_one_change(base, epollop, ch) < 0) - r = -1; - } - - return (r); -} - -static int -epoll_nochangelist_add(struct event_base *base, evutil_socket_t fd, - short old, short events, void *p) -{ - struct event_change ch; - ch.fd = fd; - ch.old_events = old; - ch.read_change = ch.write_change = ch.close_change = 0; - if (events & EV_WRITE) - ch.write_change = EV_CHANGE_ADD | - (events & EV_ET); - if (events & EV_READ) - ch.read_change = EV_CHANGE_ADD | - (events & EV_ET); - if (events & EV_CLOSED) - ch.close_change = EV_CHANGE_ADD | - (events & EV_ET); - - return epoll_apply_one_change(base, base->evbase, &ch); -} - -static int -epoll_nochangelist_del(struct event_base *base, evutil_socket_t fd, - short old, short events, void *p) -{ - struct event_change ch; - ch.fd = fd; - ch.old_events = old; - ch.read_change = ch.write_change = ch.close_change = 0; - if (events & EV_WRITE) - ch.write_change = EV_CHANGE_DEL; - if (events & EV_READ) - ch.read_change = EV_CHANGE_DEL; - if (events & EV_CLOSED) - ch.close_change = EV_CHANGE_DEL; - - return epoll_apply_one_change(base, base->evbase, &ch); -} - -static int -epoll_dispatch(struct event_base *base, struct timeval *tv) -{ - struct epollop *epollop = base->evbase; - struct epoll_event *events = epollop->events; - int i, res; - long timeout = -1; - -#ifdef USING_TIMERFD - if (epollop->timerfd >= 0) { - struct itimerspec is; - is.it_interval.tv_sec = 0; - is.it_interval.tv_nsec = 0; - if (tv == NULL) { - /* No timeout; disarm the timer. */ - is.it_value.tv_sec = 0; - is.it_value.tv_nsec = 0; - } else { - if (tv->tv_sec == 0 && tv->tv_usec == 0) { - /* we need to exit immediately; timerfd can't - * do that. */ - timeout = 0; - } - is.it_value.tv_sec = tv->tv_sec; - is.it_value.tv_nsec = tv->tv_usec * 1000; - } - /* TODO: we could avoid unnecessary syscalls here by only - calling timerfd_settime when the top timeout changes, or - when we're called with a different timeval. - */ - if (timerfd_settime(epollop->timerfd, 0, &is, NULL) < 0) { - event_warn("timerfd_settime"); - } - } else -#endif - if (tv != NULL) { - timeout = evutil_tv_to_msec_(tv); - if (timeout < 0 || timeout > MAX_EPOLL_TIMEOUT_MSEC) { - /* Linux kernels can wait forever if the timeout is - * too big; see comment on MAX_EPOLL_TIMEOUT_MSEC. */ - timeout = MAX_EPOLL_TIMEOUT_MSEC; - } - } - - epoll_apply_changes(base); - event_changelist_remove_all_(&base->changelist, base); - - EVBASE_RELEASE_LOCK(base, th_base_lock); - - res = epoll_wait(epollop->epfd, events, epollop->nevents, timeout); - - EVBASE_ACQUIRE_LOCK(base, th_base_lock); - - if (res == -1) { - if (errno != EINTR) { - event_warn("epoll_wait"); - return (-1); - } - - return (0); - } - - event_debug(("%s: epoll_wait reports %d", __func__, res)); - EVUTIL_ASSERT(res <= epollop->nevents); - - for (i = 0; i < res; i++) { - int what = events[i].events; - short ev = 0; -#ifdef USING_TIMERFD - if (events[i].data.fd == epollop->timerfd) - continue; -#endif - - if (what & (EPOLLHUP|EPOLLERR)) { - ev = EV_READ | EV_WRITE; - } else { - if (what & EPOLLIN) - ev |= EV_READ; - if (what & EPOLLOUT) - ev |= EV_WRITE; - if (what & EPOLLRDHUP) - ev |= EV_CLOSED; - } - - if (!ev) - continue; - - evmap_io_active_(base, events[i].data.fd, ev | EV_ET); - } - - if (res == epollop->nevents && epollop->nevents < MAX_NEVENT) { - /* We used all of the event space this time. We should - be ready for more events next time. */ - int new_nevents = epollop->nevents * 2; - struct epoll_event *new_events; - - new_events = mm_realloc(epollop->events, - new_nevents * sizeof(struct epoll_event)); - if (new_events) { - epollop->events = new_events; - epollop->nevents = new_nevents; - } - } - - return (0); -} - - -static void -epoll_dealloc(struct event_base *base) -{ - struct epollop *epollop = base->evbase; - - evsig_dealloc_(base); - if (epollop->events) - mm_free(epollop->events); - if (epollop->epfd >= 0) - close(epollop->epfd); -#ifdef USING_TIMERFD - if (epollop->timerfd >= 0) - close(epollop->timerfd); -#endif - - memset(epollop, 0, sizeof(struct epollop)); - mm_free(epollop); -} - -#endif /* EVENT__HAVE_EPOLL */ |