| /* |
| * Copyright (C) 2017 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.android.car.obd2; |
| |
| import android.os.SystemClock; |
| import android.util.JsonWriter; |
| import android.util.Log; |
| import com.android.car.obd2.Obd2Command.FreezeFrameCommand; |
| import com.android.car.obd2.Obd2Command.OutputSemanticHandler; |
| import java.io.IOException; |
| import java.util.ArrayList; |
| import java.util.List; |
| import java.util.Optional; |
| import java.util.Set; |
| |
| public class Obd2FreezeFrameGenerator { |
| public static final String FRAME_TYPE_FREEZE = "freeze"; |
| public static final String TAG = Obd2FreezeFrameGenerator.class.getSimpleName(); |
| |
| private final Obd2Connection mConnection; |
| private final List<OutputSemanticHandler<Integer>> mIntegerCommands = new ArrayList<>(); |
| private final List<OutputSemanticHandler<Float>> mFloatCommands = new ArrayList<>(); |
| |
| private List<String> mPreviousDtcs = new ArrayList<>(); |
| |
| public Obd2FreezeFrameGenerator(Obd2Connection connection) |
| throws IOException, InterruptedException { |
| mConnection = connection; |
| Set<Integer> connectionPids = connection.getSupportedPIDs(); |
| Set<Integer> apiIntegerPids = Obd2Command.getSupportedIntegerCommands(); |
| Set<Integer> apiFloatPids = Obd2Command.getSupportedFloatCommands(); |
| apiIntegerPids |
| .stream() |
| .filter(connectionPids::contains) |
| .forEach((Integer pid) -> mIntegerCommands.add(Obd2Command.getIntegerCommand(pid))); |
| apiFloatPids |
| .stream() |
| .filter(connectionPids::contains) |
| .forEach((Integer pid) -> mFloatCommands.add(Obd2Command.getFloatCommand(pid))); |
| Log.i( |
| TAG, |
| String.format( |
| "connectionPids = %s\napiIntegerPids=%s\napiFloatPids = %s\n" |
| + "mIntegerCommands = %s\nmFloatCommands = %s\n", |
| connectionPids, |
| apiIntegerPids, |
| apiFloatPids, |
| mIntegerCommands, |
| mFloatCommands)); |
| } |
| |
| public JsonWriter generate(JsonWriter jsonWriter) throws IOException, InterruptedException { |
| return generate(jsonWriter, SystemClock.elapsedRealtimeNanos()); |
| } |
| |
| // OBD2 does not have a notion of timestamping the fault codes |
| // As such, we need to perform additional magic in order to figure out |
| // whether a fault code we retrieved is the same as a fault code we already |
| // saw in a past iteration. The logic goes as follows: |
| // for every position i in currentDtcs, if mPreviousDtcs[i] is the same |
| // fault code, then assume they are identical. If they are not the same fault code, |
| // then everything in currentDtcs[i...size()) is assumed to be a new fault code as |
| // something in the list must have moved around; if currentDtcs is shorter than |
| // mPreviousDtcs then obviously exit at the end of currentDtcs; if currentDtcs |
| // is longer, however, anything in currentDtcs past the end of mPreviousDtcs is a new |
| // fault code and will be included |
| private final class FreezeFrameIdentity { |
| public final String dtc; |
| public final int id; |
| |
| FreezeFrameIdentity(String dtc, int id) { |
| this.dtc = dtc; |
| this.id = id; |
| } |
| } |
| |
| private List<FreezeFrameIdentity> discoverNewDtcs(List<String> currentDtcs) { |
| List<FreezeFrameIdentity> newDtcs = new ArrayList<>(); |
| int currentIndex = 0; |
| boolean inCopyAllMode = false; |
| |
| for (; currentIndex < currentDtcs.size(); ++currentIndex) { |
| if (currentIndex == mPreviousDtcs.size()) { |
| // we have more current DTCs than previous DTCs, copy everything |
| inCopyAllMode = true; |
| break; |
| } |
| if (!currentDtcs.get(currentIndex).equals(mPreviousDtcs.get(currentIndex))) { |
| // we found a different DTC, copy everything |
| inCopyAllMode = true; |
| break; |
| } |
| // same DTC, not at end of either list yet, keep looping |
| } |
| |
| if (inCopyAllMode) { |
| for (; currentIndex < currentDtcs.size(); ++currentIndex) { |
| newDtcs.add(new FreezeFrameIdentity(currentDtcs.get(currentIndex), currentIndex)); |
| } |
| } |
| |
| return newDtcs; |
| } |
| |
| public JsonWriter generate(JsonWriter jsonWriter, long timestamp) |
| throws IOException, InterruptedException { |
| List<String> currentDtcs = mConnection.getDiagnosticTroubleCodes(); |
| List<FreezeFrameIdentity> newDtcs = discoverNewDtcs(currentDtcs); |
| mPreviousDtcs = currentDtcs; |
| for (FreezeFrameIdentity freezeFrame : newDtcs) { |
| jsonWriter.beginObject(); |
| jsonWriter.name("type").value(FRAME_TYPE_FREEZE); |
| jsonWriter.name("timestamp").value(timestamp); |
| jsonWriter.name("stringValue").value(freezeFrame.dtc); |
| jsonWriter.name("intValues").beginArray(); |
| for (OutputSemanticHandler<Integer> handler : mIntegerCommands) { |
| FreezeFrameCommand<Integer> command = |
| Obd2Command.getFreezeFrameCommand(handler, freezeFrame.id); |
| try { |
| Optional<Integer> result = command.run(mConnection); |
| if (result.isPresent()) { |
| jsonWriter.beginObject(); |
| jsonWriter.name("id").value(command.getPid()); |
| jsonWriter.name("value").value(result.get()); |
| jsonWriter.endObject(); |
| } |
| } catch (IOException | InterruptedException e) { |
| Log.w( |
| TAG, |
| String.format( |
| "unable to retrieve OBD2 pid %d due to exception: %s", |
| command.getPid(), e)); |
| // skip this entry |
| } |
| } |
| jsonWriter.endArray(); |
| jsonWriter.name("floatValues").beginArray(); |
| for (OutputSemanticHandler<Float> handler : mFloatCommands) { |
| FreezeFrameCommand<Float> command = |
| Obd2Command.getFreezeFrameCommand(handler, freezeFrame.id); |
| try { |
| Optional<Float> result = command.run(mConnection); |
| if (result.isPresent()) { |
| jsonWriter.beginObject(); |
| jsonWriter.name("id").value(command.getPid()); |
| jsonWriter.name("value").value(result.get()); |
| jsonWriter.endObject(); |
| } |
| } catch (IOException | InterruptedException e) { |
| Log.w( |
| TAG, |
| String.format( |
| "unable to retrieve OBD2 pid %d due to exception: %s", |
| command.getPid(), e)); |
| // skip this entry |
| } |
| } |
| jsonWriter.endArray(); |
| jsonWriter.endObject(); |
| } |
| return jsonWriter; |
| } |
| } |