root/media/base/keyboard_event_counter.cc

DEFINITIONS

1. Reset
2. OnKeyboardEvent
3. GetKeyPressCount

// Copyright 2013 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "media/base/keyboard_event_counter.h"

#include "base/atomicops.h"
#include "base/logging.h"

namespace media {

KeyboardEventCounter::KeyboardEventCounter() : total_key_presses_(0) {}

KeyboardEventCounter::~KeyboardEventCounter() {}

void KeyboardEventCounter::Reset() {
  pressed_keys_.clear();
  base::subtle::NoBarrier_Store(
      reinterpret_cast<base::subtle::AtomicWord*>(&total_key_presses_), 0);
}

void KeyboardEventCounter::OnKeyboardEvent(ui::EventType event,
                                           ui::KeyboardCode key_code) {
  // Updates the pressed keys and the total count of key presses.
  if (event == ui::ET_KEY_PRESSED) {
    if (pressed_keys_.find(key_code) != pressed_keys_.end())
      return;
    pressed_keys_.insert(key_code);
    base::subtle::NoBarrier_AtomicIncrement(
        reinterpret_cast<base::subtle::AtomicWord*>(&total_key_presses_), 1);
  } else {
    DCHECK_EQ(ui::ET_KEY_RELEASED, event);
    pressed_keys_.erase(key_code);
  }
}

size_t KeyboardEventCounter::GetKeyPressCount() const {
  return base::subtle::NoBarrier_Load(
      reinterpret_cast<const base::subtle::AtomicWord*>(&total_key_presses_));
}

}  // namespace media