Split out QuicAlarm creation from QuicConnectionHelper to new QuicAlarmFactory. No behavior change,…

net/tools/quic/quic_epoll_alarm_factory.cc

+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "net/tools/quic/quic_epoll_alarm_factory.h"
+
+#include "base/logging.h"
+#include "net/tools/epoll_server/epoll_server.h"
+
+namespace net {
+
+namespace {
+
+class QuicEpollAlarm : public QuicAlarm {
+ public:
+  QuicEpollAlarm(EpollServer* epoll_server,
+                 QuicArenaScopedPtr<Delegate> delegate)
+      : QuicAlarm(std::move(delegate)),
+        epoll_server_(epoll_server),
+        epoll_alarm_impl_(this) {}
+
+ protected:
+  void SetImpl() override {
+    DCHECK(deadline().IsInitialized());
+    epoll_server_->RegisterAlarm(
+        deadline().Subtract(QuicTime::Zero()).ToMicroseconds(),
+        &epoll_alarm_impl_);
+  }
+
+  void CancelImpl() override {
+    DCHECK(!deadline().IsInitialized());
+    epoll_alarm_impl_.UnregisterIfRegistered();
+  }
+
+ private:
+  class EpollAlarmImpl : public EpollAlarm {
+   public:
+    explicit EpollAlarmImpl(QuicEpollAlarm* alarm) : alarm_(alarm) {}
+
+    int64_t OnAlarm() override {
+      EpollAlarm::OnAlarm();
+      alarm_->Fire();
+      // Fire will take care of registering the alarm, if needed.
+      return 0;
+    }
+
+   private:
+    QuicEpollAlarm* alarm_;
+  };
+
+  EpollServer* epoll_server_;
+  EpollAlarmImpl epoll_alarm_impl_;
+};
+
+}  // namespace
+
+QuicEpollAlarmFactory::QuicEpollAlarmFactory(EpollServer* epoll_server)
+    : epoll_server_(epoll_server) {}
+
+QuicEpollAlarmFactory::~QuicEpollAlarmFactory() {}
+
+QuicAlarm* QuicEpollAlarmFactory::CreateAlarm(
+    QuicAlarm::Delegate* delegate) {
+  return new QuicEpollAlarm(epoll_server_,
+                            QuicArenaScopedPtr<QuicAlarm::Delegate>(delegate));
+}
+
+QuicArenaScopedPtr<QuicAlarm> QuicEpollAlarmFactory::CreateAlarm(
+    QuicArenaScopedPtr<QuicAlarm::Delegate> delegate,
+    QuicConnectionArena* arena) {
+  if (arena != nullptr) {
+    return arena->New<QuicEpollAlarm>(epoll_server_, std::move(delegate));
+  } else {
+    return QuicArenaScopedPtr<QuicAlarm>(
+        new QuicEpollAlarm(epoll_server_, std::move(delegate)));
+  }
+}
+
+}  // namespace net