inline SystemState GetNextState()

in cc/src/core/state_transitions.h [55:147]
87 lines of code
29 McCabe index (conditional complexity)

  inline SystemState GetNextState() const {
    switch(action) {
    case Action::CheckpointFull:
      switch(phase) {
      case Phase::REST:
        return SystemState{ Action::CheckpointFull, Phase::PREP_INDEX_CHKPT, version };
      case Phase::PREP_INDEX_CHKPT:
        return SystemState{ Action::CheckpointFull, Phase::INDEX_CHKPT, version };
      case Phase::INDEX_CHKPT:
        return SystemState{ Action::CheckpointFull, Phase::PREPARE, version };
      case Phase::PREPARE:
        return SystemState{ Action::CheckpointFull, Phase::IN_PROGRESS, version + 1 };
      case Phase::IN_PROGRESS:
        return SystemState{ Action::CheckpointFull, Phase::WAIT_PENDING, version };
      case Phase::WAIT_PENDING:
        return SystemState{ Action::CheckpointFull, Phase::WAIT_FLUSH, version };
      case Phase::WAIT_FLUSH:
        return SystemState{ Action::CheckpointFull, Phase::PERSISTENCE_CALLBACK, version };
      case Phase::PERSISTENCE_CALLBACK:
        return SystemState{ Action::CheckpointFull, Phase::REST, version };
      default:
        // not reached
        assert(false);
        return SystemState(UINT64_MAX);
      }
      break;
    case Action::CheckpointIndex:
      switch(phase) {
      case Phase::REST:
        return SystemState{ Action::CheckpointIndex, Phase::PREP_INDEX_CHKPT, version };
      case Phase::PREP_INDEX_CHKPT:
        return SystemState{ Action::CheckpointIndex, Phase::INDEX_CHKPT, version };
      case Phase::INDEX_CHKPT:
        return SystemState{ Action::CheckpointIndex, Phase::REST, version };
      default:
        // not reached
        assert(false);
        return SystemState(UINT64_MAX);
      }
      break;
    case Action::CheckpointHybridLog:
      switch(phase) {
      case Phase::REST:
        return SystemState{ Action::CheckpointHybridLog, Phase::PREPARE, version };
      case Phase::PREPARE:
        return SystemState{ Action::CheckpointHybridLog, Phase::IN_PROGRESS, version + 1 };
      case Phase::IN_PROGRESS:
        return SystemState{ Action::CheckpointHybridLog, Phase::WAIT_PENDING, version };
      case Phase::WAIT_PENDING:
        return SystemState{ Action::CheckpointHybridLog, Phase::WAIT_FLUSH, version };
      case Phase::WAIT_FLUSH:
        return SystemState{ Action::CheckpointHybridLog, Phase::PERSISTENCE_CALLBACK, version };
      case Phase::PERSISTENCE_CALLBACK:
        return SystemState{ Action::CheckpointHybridLog, Phase::REST, version };
      default:
        // not reached
        assert(false);
        return SystemState(UINT64_MAX);
      }
      break;
    case Action::GC:
      switch(phase) {
      case Phase::REST:
        return SystemState{ Action::GC, Phase::GC_IO_PENDING, version };
      case Phase::GC_IO_PENDING:
        return SystemState{ Action::GC, Phase::GC_IN_PROGRESS, version };
      case Phase::GC_IN_PROGRESS:
        return SystemState{ Action::GC, Phase::REST, version };
      default:
        // not reached
        assert(false);
        return SystemState(UINT64_MAX);
      }
      break;
    case Action::GrowIndex:
      switch(phase) {
      case Phase::REST:
        return SystemState{ Action::GrowIndex, Phase::GROW_PREPARE, version };
      case Phase::GROW_PREPARE:
        return SystemState{ Action::GrowIndex, Phase::GROW_IN_PROGRESS, version };
      case Phase::GROW_IN_PROGRESS:
        return SystemState{ Action::GrowIndex, Phase::REST, version };
      default:
        // not reached
        assert(false);
        return SystemState(UINT64_MAX);
      }
    default:
      // not reached
      assert(false);
      return SystemState(UINT64_MAX);
    }
  }