remoting/client/key_event_mapper.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_CLIENT_KEY_EVENT_MAPPER_H_
   6 #define REMOTING_CLIENT_KEY_EVENT_MAPPER_H_
   7
   8 #include <map>
   9 #include <set>
  10
  11 #include "base/basictypes.h"
  12 #include "base/callback.h"
  13 #include "base/compiler_specific.h"
  14 #include "remoting/protocol/input_filter.h"
  15
  16 namespace remoting {
  17
  18 // Filtering InputStub which can be used to re-map the USB keycodes of events
  19 // before they are passed on to the next InputStub in the chain, or to trap
  20 // events with specific USB keycodes for special handling.
  21 class KeyEventMapper : public protocol::InputFilter {
  22  public:
  23   KeyEventMapper();
  24   explicit KeyEventMapper(InputStub* input_stub);
  25   ~KeyEventMapper() override;
  26
  27   // Callback type for use with SetTrapCallback(), below.
  28   typedef base::Callback<void(const protocol::KeyEvent&)> KeyTrapCallback;
  29
  30   // Sets the callback to which trapped keys will be delivered.
  31   void SetTrapCallback(KeyTrapCallback callback);
  32
  33   // Causes events matching |usb_keycode| to be delivered to the trap callback.
  34   // Trapped events are not dispatched to the next InputStub in the chain.
  35   void TrapKey(uint32 usb_keycode, bool trap_key);
  36
  37   // Causes events matching |in_usb_keycode| to be mapped to |out_usb_keycode|.
  38   // Keys are remapped at most once. Traps are processed before remapping.
  39   void RemapKey(uint32 in_usb_keycode, uint32 out_usb_keycode);
  40
  41   // InputFilter overrides.
  42   void InjectKeyEvent(const protocol::KeyEvent& event) override;
  43
  44  private:
  45   std::map<uint32,uint32> mapped_keys;
  46   std::set<uint32> trapped_keys;
  47   KeyTrapCallback trap_callback;
  48
  49   DISALLOW_COPY_AND_ASSIGN(KeyEventMapper);
  50 };
  51
  52 } // namespace remoting
  53
  54 #endif // REMOTING_CLIENT_KEY_EVENT_MAPPER_H_