120 lines
2.9 KiB
C++
120 lines
2.9 KiB
C++
/*
|
|
* Copyright (c) Facebook, Inc. and its affiliates.
|
|
*
|
|
* Licensed under the Apache License, Version 2.0 (the "License");
|
|
* you may not use this file except in compliance with the License.
|
|
* You may obtain a copy of the License at
|
|
*
|
|
* http://www.apache.org/licenses/LICENSE-2.0
|
|
*
|
|
* Unless required by applicable law or agreed to in writing, software
|
|
* distributed under the License is distributed on an "AS IS" BASIS,
|
|
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
* See the License for the specific language governing permissions and
|
|
* limitations under the License.
|
|
*/
|
|
|
|
#include <folly/io/async/EventBaseBackendBase.h>
|
|
|
|
#include <folly/io/async/EventBase.h>
|
|
|
|
#if defined(__linux__) && !FOLLY_MOBILE
|
|
#define FOLLY_USE_EPOLLET
|
|
|
|
#include <sys/epoll.h>
|
|
|
|
struct event_base {
|
|
void* evsel;
|
|
void* evbase;
|
|
};
|
|
|
|
struct epollop {
|
|
void* fds;
|
|
int nfds;
|
|
void* events;
|
|
int nevents;
|
|
int epfd;
|
|
};
|
|
#endif
|
|
|
|
namespace folly {
|
|
void EventBaseEvent::eb_ev_base(EventBase* evb) {
|
|
evb_ = evb;
|
|
event_.ev_base = evb ? evb->getLibeventBase() : nullptr;
|
|
}
|
|
|
|
int EventBaseEvent::eb_event_base_set(EventBase* evb) {
|
|
evb_ = evb;
|
|
auto* base = evb_ ? (evb_->getLibeventBase()) : nullptr;
|
|
if (base) {
|
|
return ::event_base_set(base, &event_);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int EventBaseEvent::eb_event_add(const struct timeval* timeout) {
|
|
auto* backend = evb_ ? (evb_->getBackend()) : nullptr;
|
|
if (backend) {
|
|
return backend->eb_event_add(*this, timeout);
|
|
}
|
|
|
|
return -1;
|
|
}
|
|
|
|
int EventBaseEvent::eb_event_del() {
|
|
auto* backend = evb_ ? (evb_->getBackend()) : nullptr;
|
|
if (backend) {
|
|
return backend->eb_event_del(*this);
|
|
}
|
|
|
|
return -1;
|
|
}
|
|
|
|
bool EventBaseEvent::eb_event_active(int res) {
|
|
auto* backend = evb_ ? (evb_->getBackend()) : nullptr;
|
|
if (backend) {
|
|
return backend->eb_event_active(*this, res);
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
bool EventBaseEvent::setEdgeTriggered() {
|
|
#ifdef FOLLY_USE_EPOLLET
|
|
// Until v2 libevent doesn't expose API to set edge-triggered flag for events.
|
|
// If epoll backend is used by libevent, we can enable it though epoll_ctl
|
|
// directly.
|
|
// Note that this code depends on internal event_base and epollop layout, so
|
|
// we have to validate libevent version.
|
|
static const bool supportedVersion =
|
|
!strcmp(event_get_version(), "1.4.14b-stable");
|
|
if (!supportedVersion) {
|
|
return false;
|
|
}
|
|
auto* base = evb_ ? (evb_->getLibeventBase()) : nullptr;
|
|
if (!base || strcmp(event_base_get_method(base), "epoll")) {
|
|
return false;
|
|
}
|
|
|
|
auto epfd = static_cast<epollop*>(base->evbase)->epfd;
|
|
epoll_event epev = {0, {0}};
|
|
epev.data.fd = eb_ev_fd();
|
|
epev.events = EPOLLET;
|
|
if (eb_ev_events() & EV_READ) {
|
|
epev.events |= EPOLLIN;
|
|
}
|
|
if (eb_ev_events() & EV_WRITE) {
|
|
epev.events |= EPOLLOUT;
|
|
}
|
|
if (::epoll_ctl(epfd, EPOLL_CTL_MOD, eb_ev_fd(), &epev) == -1) {
|
|
LOG(DFATAL) << "epoll_ctl failed: " << errno;
|
|
return false;
|
|
}
|
|
return true;
|
|
#else
|
|
return false;
|
|
#endif
|
|
}
|
|
} // namespace folly
|