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
  10 namespace ui {
  11
  12 base::StaticAtomicSequenceNumber g_next_event_id;
  13
  14 uint32 GetNextTouchEventId() {
  15   // Set the first touch event ID to 1 because we set id to 0 for other types
  16   // of events.
  17   uint32 id = g_next_event_id.GetNext();
  18   if (id == 0)
  19     id = g_next_event_id.GetNext();
  20   DCHECK_NE(0U, id);
  21   return id;
  22 }
  23
  24 }  // namespace ui
  25