vn-verdnaturachat/ios/Pods/Flipper-Folly/folly/io/async/AsyncSignalHandler.cpp

100 lines
2.8 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/AsyncSignalHandler.h>
#include <folly/io/async/EventBase.h>
#include <folly/Conv.h>
using std::make_pair;
using std::pair;
using std::string;
namespace folly {
AsyncSignalHandler::AsyncSignalHandler(EventBase* eventBase)
: eventBase_(eventBase) {}
AsyncSignalHandler::~AsyncSignalHandler() {
// Unregister any outstanding events
for (auto& signalEvent : signalEvents_) {
signalEvent.second->eb_event_del();
}
}
void AsyncSignalHandler::attachEventBase(EventBase* eventBase) {
assert(eventBase_ == nullptr);
assert(signalEvents_.empty());
eventBase_ = eventBase;
}
void AsyncSignalHandler::detachEventBase() {
assert(eventBase_ != nullptr);
assert(signalEvents_.empty());
eventBase_ = nullptr;
}
void AsyncSignalHandler::registerSignalHandler(int signum) {
pair<SignalEventMap::iterator, bool> ret = signalEvents_.insert(
make_pair(signum, std::make_unique<EventBaseEvent>()));
if (!ret.second) {
// This signal has already been registered
throw std::runtime_error(
folly::to<string>("handler already registered for signal ", signum));
}
EventBaseEvent* ev = ret.first->second.get();
try {
ev->eb_signal_set(signum, libeventCallback, this);
if (ev->eb_event_base_set(eventBase_) != 0) {
throw std::runtime_error(folly::to<string>(
"error initializing event handler for signal ", signum));
}
if (ev->eb_event_add(nullptr) != 0) {
throw std::runtime_error(
folly::to<string>("error adding event handler for signal ", signum));
}
} catch (...) {
signalEvents_.erase(ret.first);
throw;
}
}
void AsyncSignalHandler::unregisterSignalHandler(int signum) {
auto it = signalEvents_.find(signum);
if (it == signalEvents_.end()) {
throw std::runtime_error(folly::to<string>(
"unable to unregister handler for signal ",
signum,
": signal not registered"));
}
it->second->eb_event_del();
signalEvents_.erase(it);
}
void AsyncSignalHandler::libeventCallback(
libevent_fd_t signum,
short /* events */,
void* arg) {
auto handler = static_cast<AsyncSignalHandler*>(arg);
handler->signalReceived(int(signum));
}
} // namespace folly