realm-js/apple/external_commit_helper.hpp

93 lines
2.5 KiB
C++

////////////////////////////////////////////////////////////////////////////
//
// Copyright 2015 Realm Inc.
//
// 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.
//
////////////////////////////////////////////////////////////////////////////
#ifndef REALM_EXTERNAL_COMMIT_HELPER_HPP
#define REALM_EXTERNAL_COMMIT_HELPER_HPP
#include <CoreFoundation/CFRunLoop.h>
#include <mutex>
#include <vector>
namespace realm {
class Realm;
class ExternalCommitHelper {
public:
ExternalCommitHelper(Realm* realm);
~ExternalCommitHelper();
void notify_others();
void add_realm(Realm* realm);
void remove_realm(Realm* realm);
private:
// A RAII holder for a file descriptor which automatically closes the wrapped
// fd when it's deallocated
class FdHolder {
public:
FdHolder() = default;
~FdHolder() { close(); }
operator int() const { return m_fd; }
FdHolder& operator=(int newFd) {
close();
m_fd = newFd;
return *this;
}
private:
int m_fd = -1;
void close();
FdHolder& operator=(FdHolder const&) = delete;
FdHolder(FdHolder const&) = delete;
};
struct PerRealmInfo {
Realm* realm;
CFRunLoopRef runloop;
CFRunLoopSourceRef signal;
};
void listen();
// Currently registered realms and the signal for delivering notifications
// to them
std::vector<PerRealmInfo> m_realms;
// Mutex which guards m_realms
std::mutex m_realms_mutex;
// The listener thread
pthread_t m_thread;
// Read-write file descriptor for the named pipe which is waited on for
// changes and written to when a commit is made
FdHolder m_notify_fd;
// File descriptor for the kqueue
FdHolder m_kq;
// The two ends of an anonymous pipe used to notify the kqueue() thread that
// it should be shut down.
FdHolder m_shutdown_read_fd;
FdHolder m_shutdown_write_fd;
};
} // namespace realm
#endif /* REALM_EXTERNAL_COMMIT_HELPER_HPP */