Merge with head.

MyTracks/src/com/google/android/apps/mytracks/SettingsActivity.java

@@ -232,7 +232,8 @@ public class SettingsActivity extends PreferenceActivity {
 
   private void updateSensorSettings(String sensorType) {
     boolean usesBluetooth =
-        getString(R.string.zephyr_sensor_type).equals(sensorType);
+        getString(R.string.zephyr_sensor_type).equals(sensorType)
+        || getString(R.string.polar_sensor_type).equals(sensorType);
     findPreference(
         getString(R.string.bluetooth_sensor_key)).setEnabled(usesBluetooth);
     findPreference(

MyTracks/src/com/google/android/apps/mytracks/services/sensors/BluetoothConnectionManager.java

@@ -394,8 +394,9 @@ public class BluetoothConnectionManager {
 
           offset = 0;
 
-          // Send the obtained bytes to the UI Activity
-          handler.obtainMessage(MESSAGE_READ, bytes, -1, buffer)
+          // Send copy of the obtained bytes to the UI Activity.
+          // Avoids memory inconsistency issues.
+          handler.obtainMessage(MESSAGE_READ, bytes, -1, buffer.clone())
               .sendToTarget();
         } catch (IOException e) {
           Log.e(Constants.TAG, "disconnected", e);

MyTracks/src/com/google/android/apps/mytracks/services/sensors/PolarMessageParser.java

@@ -0,0 +1,140 @@
+/*
+ * Copyright 2011 Google Inc.
+ *
+ * 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.google.android.apps.mytracks.services.sensors;
+
+import com.google.android.apps.mytracks.content.Sensor;
+
+/**
+ * An implementation of a Sensor MessageParser for Polar Wearlink Bluetooth HRM.
+ *
+ *  Polar Bluetooth Wearlink packet example;
+ *   Hdr Len Chk Seq Status HeartRate RRInterval_16-bits
+ *    FE  08  F7  06   F1      48          03 64
+ *   where; 
+ *      Hdr always = 254 (0xFE), 
+ *      Chk = 255 - Len
+ *      Seq range 0 to 15
+ *      Status = Upper nibble may be battery voltage
+ *               bit 0 is Beat Detection flag.
+ *               
+ *  Additional packet examples;
+ *    FE 08 F7 06 F1 48 03 64           
+ *    FE 0A F5 06 F1 48 03 64 03 70
+ *    
+ * @author John R. Gerthoffer
+ */
+public class PolarMessageParser implements MessageParser {
+
+  private int lastHeartRate = 0;                   
+
+  /**
+   * Applies Polar packet validation rules to buffer.
+   *   Polar packets are checked for following;
+   *     offset 0 = header byte, 254 (0xFE).
+   *     offset 1 = packet length byte, 8, 10, 12, 14.
+   *     offset 2 = check byte, 255 - packet length.
+   *     offset 3 = sequence byte, range from 0 to 15.
+   *     
+   * @param an array of bytes to parse
+   * @param buffer offset to beginning of packet.  
+   * @return whether buffer has a valid packet at offset i
+   */
+  private boolean packetValid (byte[] buffer, int i) {
+    boolean headerValid = (buffer[i] & 0xFF) == 0xFE;
+    boolean checkbyteValid = (buffer[i + 2] & 0xFF) == (0xFF - (buffer[i + 1] & 0xFF));
+    boolean sequenceValid = (buffer[i + 3] & 0xFF) < 16;
+    
+    return headerValid && checkbyteValid && sequenceValid;
+  }
+  
+  @Override
+  public Sensor.SensorDataSet parseBuffer(byte[] buffer) {
+
+    int heartRate = 0;
+    boolean heartrateValid = false; 
+    
+    // Minimum length Polar packets is 8, so stop search 8 bytes before buffer ends.
+    for (int i = 0; i < buffer.length - 8; i++) {
+      heartrateValid = packetValid(buffer,i); 
+      if (heartrateValid)  {
+        heartRate = buffer[i + 5] & 0xFF;
+        break; 
+      }
+    }
+
+    // If our buffer is corrupted, use decaying last good value.
+    if(!heartrateValid) {
+      heartRate = (int) (lastHeartRate * 0.8);  
+      if(heartRate < 50)
+        heartRate = 0;
+    }
+
+    lastHeartRate = heartRate;                          // Remember good value for next time.
+
+    // Heart Rate
+    Sensor.SensorData.Builder b = Sensor.SensorData.newBuilder()
+      .setValue(heartRate)
+      .setState(Sensor.SensorState.SENDING);
+
+    Sensor.SensorDataSet sds = Sensor.SensorDataSet.newBuilder()
+      .setCreationTime(System.currentTimeMillis())
+      .setHeartRate(b)
+      .build();
+    
+    return sds;
+  }
+
+  /**
+   * Applies packet validation rules to buffer
+   *     
+   * @param an array of bytes to parse
+   * @return whether buffer has a valid packet starting at index zero
+   */
+  @Override
+  public boolean isValid(byte[] buffer) {
+    return packetValid(buffer,0);
+  }
+
+  /**
+   * Polar uses variable packet sizes; 8, 10, 12, 14 and rarely 16.
+   * The most frequent are 8 and 10.
+   * We will wait for 16 bytes.
+   * This way, we are assured of getting one good one.
+   * 
+   * @return the size of buffer needed to parse a good packet
+   */
+  @Override
+  public int getFrameSize() {
+	return 16;									
+  }
+
+  /**
+   * Searches buffer for the beginning of a valid packet.
+   *     
+   * @param an array of bytes to parse
+   * @return index to beginning of good packet, or -1 if none found.
+   */
+  @Override
+  public int findNextAlignment(byte[] buffer) {
+    // Minimum length Polar packets is 8, so stop search 8 bytes before buffer ends.
+    for (int i = 0; i < buffer.length - 8; i++) {
+      if (packetValid(buffer,i)) {
+	    return i;
+      }
+    }
+    return -1;
+  }
+}

MyTracks/src/com/google/android/apps/mytracks/services/sensors/PolarSensorManager.java

@@ -0,0 +1,28 @@
+/*
+ * Copyright 2011 Google Inc.
+ *
+ * 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.google.android.apps.mytracks.services.sensors;
+
+import android.content.Context;
+
+/**
+ * PolarSensorManager - A sensor manager for Polar heart rate monitors.
+ */
+
+public class PolarSensorManager extends BluetoothSensorManager {
+  public PolarSensorManager(Context context) {
+    super(context, new PolarMessageParser());
+  }
+}

MyTracks/src/com/google/android/apps/mytracks/services/sensors/SensorManagerFactory.java

@@ -59,6 +59,8 @@ public class SensorManagerFactory {
       return new AntSRMSensorManager(context);
     } else if (sensor.equals(context.getString(R.string.zephyr_sensor_type))) {
       return new ZephyrSensorManager(context);
+    } else if (sensor.equals(context.getString(R.string.polar_sensor_type))) {
+      return new PolarSensorManager(context);
     } else  {
       Log.w(Constants.TAG, "Unable to find sensor type: " + sensor);
       return null;