Keep only base/extractor.[cc|h].

base/reactor.h

-// Copyright 2007-2009 Google 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.
-// ========================================================================
-//
-// reactor.{h, cc} implements the reactor design pattern.
-//
-// For each signaled handle the reactor calls back the event handler only once.
-// To get further notifications, the handle must be registered again with the
-// reactor. This may sound like a lot of work but this is the only way to
-// guarantee that the event handler is only called once.
-// UnregisterHandle can't be called when handling a callback or it results in
-// a deadlock. When handling a callback, the only possible operation is
-// registering back a handle using Register.
-
-#ifndef OMAHA_COMMON_REACTOR_H__
-#define OMAHA_COMMON_REACTOR_H__
-
-#include <windows.h>
-#include <vector>
-#include "base/basictypes.h"
-
-namespace omaha {
-
-class EventHandler;
-
-class Reactor {
- public:
-  Reactor();
-  ~Reactor();
-
-  // Starts demultiplexing and dispatching events.
-  HRESULT HandleEvents();
-
-  // Registers an event handler for a handle. The reactor does not own the
-  // handle. Registering the same handle twice results in undefined behavior.
-  // The flags parameter can be one of the WT* thread pool values or 0 for
-  // a reasonable default.
-  HRESULT RegisterHandle(HANDLE handle,
-                         EventHandler* event_handler,
-                         uint32 flags);
-
-  // Registers the handle again. This method can be called from the callback.
-  HRESULT RegisterHandle(HANDLE handle);
-
-  // Unregisters the handle. The method blocks and waits for any callback to
-  // complete if an event dispatching is in progress.
-  HRESULT UnregisterHandle(HANDLE handle);
-
- private:
-  struct RegistrationState {
-    RegistrationState()
-        : reactor(NULL),
-          event_handler(NULL),
-          handle(NULL),
-          wait_handle(NULL),
-          flags(0) {}
-
-    Reactor*      reactor;
-    EventHandler* event_handler;
-    HANDLE        handle;
-    HANDLE        wait_handle;
-    uint32        flags;
-  };
-
-  static void __stdcall Callback(void* param, BOOLEAN timer_or_wait);
-  void DoCallback(RegistrationState* registration_state);
-
-  HRESULT DoRegisterHandle(HANDLE handle);
-
-  // Releases the ownership of the registration state corresponding to a handle.
-  RegistrationState* ReleaseHandlerState(HANDLE handle);
-
-  CRITICAL_SECTION cs_;
-  std::vector<RegistrationState*> handlers_;
-
-  DISALLOW_EVIL_CONSTRUCTORS(Reactor);
-};
-
-}  // namespace omaha
-
-#endif  // OMAHA_COMMON_REACTOR_H__