Handle datarace after writer shutdown (#175)

Signed-off-by: danipiza <dpizarrogallego@gmail.com>

Author: Danipiza

ddspipe_participants/src/cpp/reader/dds/SpecificQoSReader.cpp

@@ -46,6 +46,15 @@ void SpecificQoSReader::fill_received_data_(
 {
     CommonReader::fill_received_data_(info, data_to_fill);
 
+    // During endpoint teardown, last cache changes can be processed after endpoint removal.
+    if (!data_to_fill.source_guid.is_valid())
+    {
+        logDebug(
+            DDSPIPE_SpecificQoSReader,
+            "Skipping writer QoS lookup for invalid writer GUID " << data_to_fill.source_guid << ".");
+        return;
+    }
+
     // Find qos of writer
     try
     {

ddspipe_participants/src/cpp/reader/rtps/SpecificQoSReader.cpp

@@ -49,6 +49,15 @@ void SpecificQoSReader::fill_received_data_(
 {
     CommonReader::fill_received_data_(received_change, data_to_fill);
 
+    // During endpoint teardown, last cache changes can be processed after endpoint removal.
+    if (!data_to_fill.source_guid.is_valid())
+    {
+        logDebug(
+            DDSPIPE_SpecificQoSReader,
+            "Skipping writer QoS lookup for invalid writer GUID " << data_to_fill.source_guid << ".");
+        return;
+    }
+
     // Find qos of writer
     try
     {