remoting/host/remote_input_filter.h

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef REMOTING_HOST_REMOTE_INPUT_FILTER_H_
   6 #define REMOTING_HOST_REMOTE_INPUT_FILTER_H_
   7
   8 #include <list>
   9
  10 #include "base/basictypes.h"
  11 #include "base/compiler_specific.h"
  12 #include "base/time/time.h"
  13 #include "remoting/protocol/input_event_tracker.h"
  14 #include "remoting/protocol/input_stub.h"
  15
  16 namespace remoting {
  17
  18 // Filtering InputStub that filters remotely-injected input if it has been
  19 // notified of local input recently.
  20 class RemoteInputFilter : public protocol::InputStub {
  21  public:
  22   // Creates a filter forwarding events to the specified InputEventTracker.
  23   // The filter needs a tracker to release buttons & keys when blocking input.
  24   explicit RemoteInputFilter(protocol::InputEventTracker* event_tracker);
  25   ~RemoteInputFilter() override;
  26
  27   // Informs the filter that local mouse activity has been detected.  If the
  28   // activity does not match events we injected then we assume that it is local,
  29   // and block remote input for a short while.
  30   void LocalMouseMoved(const webrtc::DesktopVector& mouse_pos);
  31
  32   // Informs the filter that injecting input causes an echo.
  33   void SetExpectLocalEcho(bool expect_local_echo);
  34
  35   // InputStub overrides.
  36   void InjectKeyEvent(const protocol::KeyEvent& event) override;
  37   void InjectTextEvent(const protocol::TextEvent& event) override;
  38   void InjectMouseEvent(const protocol::MouseEvent& event) override;
  39
  40  private:
  41   bool ShouldIgnoreInput() const;
  42
  43   protocol::InputEventTracker* event_tracker_;
  44
  45   // Queue of recently-injected mouse positions used to distinguish echoes of
  46   // injected events from movements from a local input device.
  47   std::list<webrtc::DesktopVector> injected_mouse_positions_;
  48
  49   // Time at which local input events were most recently observed.
  50   base::TimeTicks latest_local_input_time_;
  51
  52   // If |true| than the filter assumes that injecting input causes an echo.
  53   bool expect_local_echo_;
  54
  55   DISALLOW_COPY_AND_ASSIGN(RemoteInputFilter);
  56 };
  57
  58 }  // namespace remoting
  59
  60 #endif  // REMOTING_HOST_REMOTE_INPUT_FILTER_H_