ui/events/base_event_utils.cc

   1 // Copyright 2015 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 #include "ui/events/base_event_utils.h"
   6
   7 #include "base/atomic_sequence_num.h"
   8 #include "base/logging.h"
   9 #include "ui/events/event_constants.h"
  10
  11 namespace ui {
  12
  13 namespace {
  14
  15 #if defined(OS_CHROMEOS)
  16 const int kSystemKeyModifierMask = EF_ALT_DOWN | EF_COMMAND_DOWN;
  17 #else
  18 const int kSystemKeyModifierMask = EF_ALT_DOWN;
  19 #endif  // defined(OS_CHROMEOS)
  20
  21
  22 }  // namespace
  23
  24 base::StaticAtomicSequenceNumber g_next_event_id;
  25
  26 uint32 GetNextTouchEventId() {
  27   // Set the first touch event ID to 1 because we set id to 0 for other types
  28   // of events.
  29   uint32 id = g_next_event_id.GetNext();
  30   if (id == 0)
  31     id = g_next_event_id.GetNext();
  32   DCHECK_NE(0U, id);
  33   return id;
  34 }
  35
  36 bool IsSystemKeyModifier(int flags) {
  37   // AltGr modifier is used to type alternative keys on certain keyboard layouts
  38   // so we don't consider keys with the AltGr modifier as a system key.
  39   return (kSystemKeyModifierMask & flags) != 0 &&
  40          (EF_ALTGR_DOWN & flags) == 0;
  41 }
  42
  43 }  // namespace ui
  44