From 14c6ce1a3a479376543c1d7bcaa08999bba216e0 Mon Sep 17 00:00:00 2001
From: Daniele Gobbetti <daniele+cb@gobbetti.name>
Date: Sun, 7 Apr 2024 19:50:18 +0200
Subject: [PATCH] Garmin protocol: store max packet size from
 DeviceInformationMessage

also adds messageType to the warnifleftover log message
---
 .../garmin/messages/DeviceInformationMessage.java |  1 +
 .../devices/garmin/messages/GFDIMessage.java      | 15 ++++++++++++---
 2 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/garmin/messages/DeviceInformationMessage.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/garmin/messages/DeviceInformationMessage.java
index 684694ae3..95c74437a 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/garmin/messages/DeviceInformationMessage.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/garmin/messages/DeviceInformationMessage.java
@@ -35,6 +35,7 @@ public class DeviceInformationMessage extends GFDIMessage {
         this.deviceName = deviceName;
         this.deviceModel = deviceModel;
 
+        GFDIMessage.setMaxPacketSize(maxPacketSize);
         this.statusMessage = getStatusMessage();
     }
 
diff --git a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/garmin/messages/GFDIMessage.java b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/garmin/messages/GFDIMessage.java
index 0ca3ef861..1047c6b8e 100644
--- a/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/garmin/messages/GFDIMessage.java
+++ b/app/src/main/java/nodomain/freeyourgadget/gadgetbridge/service/devices/garmin/messages/GFDIMessage.java
@@ -32,10 +32,19 @@ public abstract class GFDIMessage {
     public static final int MESSAGE_SYNC_REQUEST = 5037;
     public static final int MESSAGE_AUTH_NEGOTIATION = 5101;
     protected static final Logger LOG = LoggerFactory.getLogger(GFDIMessage.class);
+    private static int maxPacketSize = 375; //safe default?
     protected final ByteBuffer response = ByteBuffer.allocate(1000);
     protected GFDIStatusMessage statusMessage;
     protected GarminMessage garminMessage;
 
+    public static int getMaxPacketSize() {
+        return maxPacketSize;
+    }
+
+    public static void setMaxPacketSize(int maxPacketSize) {
+        GFDIMessage.maxPacketSize = maxPacketSize;
+    }
+
     public static GFDIMessage parseIncoming(byte[] message) {
         final MessageReader messageReader = new MessageReader(message);
 
@@ -48,7 +57,7 @@ public abstract class GFDIMessage {
             LOG.error("UNHANDLED GFDI MESSAGE TYPE {}, MESSAGE {}", messageType, message);
             return new UnhandledMessage(messageType);
         } finally {
-            messageReader.warnIfLeftover();
+            messageReader.warnIfLeftover(messageType);
         }
     }
 
@@ -194,14 +203,14 @@ public abstract class GFDIMessage {
             }
         }
 
-        public void warnIfLeftover() {
+        public void warnIfLeftover(int messageType) {
             if (byteBuffer.hasRemaining() && byteBuffer.position() < (byteBuffer.limit())) {
                 int pos = byteBuffer.position();
                 int numBytes = (byteBuffer.limit()) - byteBuffer.position();
                 byte[] leftover = new byte[numBytes];
                 byteBuffer.get(leftover);
                 byteBuffer.position(pos);
-                LOG.warn("Leftover bytes when parsing message. Bytes: {}, complete message: {}", GB.hexdump(leftover), GB.hexdump(byteBuffer.array()));
+                LOG.warn("Leftover bytes when parsing message type {}. Bytes: {}, complete message: {}", messageType, GB.hexdump(leftover), GB.hexdump(byteBuffer.array()));
             }
         }
     }