chromecast/media/cma/backend/media_clock_device.cc

   1 // Copyright 2014 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 "chromecast/media/cma/backend/media_clock_device.h"
   6
   7 #include "base/logging.h"
   8
   9 namespace chromecast {
  10 namespace media {
  11
  12 MediaClockDevice::MediaClockDevice() {
  13 }
  14
  15 MediaClockDevice::~MediaClockDevice() {
  16 }
  17
  18 // static
  19 bool MediaClockDevice::IsValidStateTransition(State state1, State state2) {
  20   if (state2 == state1)
  21     return true;
  22
  23   // All states can transition to |kStateError|.
  24   bool is_transition_valid = (state2 == kStateError);
  25
  26   // All the other valid FSM transitions.
  27   is_transition_valid = is_transition_valid ||
  28       (state1 == kStateUninitialized && (state2 == kStateIdle)) ||
  29       (state1 == kStateIdle && (state2 == kStateRunning ||
  30                                 state2 == kStateUninitialized)) ||
  31       (state1 == kStateRunning && (state2 == kStateIdle)) ||
  32       (state1 == kStateError && (state2 == kStateUninitialized));
  33
  34   return is_transition_valid;
  35 }
  36
  37 // static
  38 std::string MediaClockDevice::StateToString(const State& state) {
  39   switch (state) {
  40     case kStateUninitialized:
  41       return "Uninitialized";
  42     case kStateIdle:
  43       return "Idle";
  44     case kStateRunning:
  45       return "Running";
  46     case kStateError:
  47       return "Error";
  48     default:
  49       NOTREACHED() << "Unknown MediaClockDevice::State: " << state;
  50       return "";
  51   }
  52 }
  53
  54 }  // namespace media
  55 }  // namespace chromecast