fix(abcip): serialize Read/GetStatus/Decode + Encode/Write/GetStatus per runtime (05/STAB-4)

archreview/plans/R2-09-driver-fleet-batch-plan.md.tasks.json

@@ -42,7 +42,7 @@
     {
       "id": "B2.3",
       "subject": "B2: wrap ReadSingleAsync/ReadGroupAsync/WriteAsync critical sections in the per-runtime lock; AbCip suite green",
-      "status": "pending",
+      "status": "completed",
       "blockedBy": [
         "B2.2"
       ]

src/Drivers/ZB.MOM.WW.OtOpcUa.Driver.AbCip/AbCipDriver.cs

@@ -542,6 +542,13 @@ public sealed class AbCipDriver : IDriver, IReadable, IWritable, ITagDiscovery,
         try
         {
             var runtime = await EnsureTagRuntimeAsync(device, def, ct).ConfigureAwait(false);
+
+            // Serialise Read → GetStatus → Decode against the shared runtime — the cached libplctag
+            // Tag handle is not concurrency-safe and GetStatus returns the LAST op's status (05/STAB-4).
+            var opLock = device.GetRuntimeLock(def.Name);
+            await opLock.WaitAsync(ct).ConfigureAwait(false);
+            try
+            {
                 await runtime.ReadAsync(ct).ConfigureAwait(false);
 
                 var status = runtime.GetStatus();
@@ -574,6 +581,11 @@ public sealed class AbCipDriver : IDriver, IReadable, IWritable, ITagDiscovery,
                 results[fb.OriginalIndex] = new DataValueSnapshot(value, AbCipStatusMapper.Good, now, now);
                 _health = new DriverHealth(DriverState.Healthy, now, null);
             }
+            finally
+            {
+                opLock.Release();
+            }
+        }
         catch (OperationCanceledException)
         {
             throw;
@@ -612,6 +624,13 @@ public sealed class AbCipDriver : IDriver, IReadable, IWritable, ITagDiscovery,
         try
         {
             var runtime = await EnsureTagRuntimeAsync(device, parent, ct).ConfigureAwait(false);
+
+            // Serialise the whole-UDT Read → GetStatus → per-member DecodeValueAt against the shared
+            // parent runtime — the members decode from that one handle's buffer (05/STAB-4).
+            var opLock = device.GetRuntimeLock(parent.Name);
+            await opLock.WaitAsync(ct).ConfigureAwait(false);
+            try
+            {
                 await runtime.ReadAsync(ct).ConfigureAwait(false);
 
                 var status = runtime.GetStatus();
@@ -636,6 +655,11 @@ public sealed class AbCipDriver : IDriver, IReadable, IWritable, ITagDiscovery,
                 }
                 _health = new DriverHealth(DriverState.Healthy, now, null);
             }
+            finally
+            {
+                opLock.Release();
+            }
+        }
         catch (OperationCanceledException)
         {
             throw;
@@ -706,10 +730,23 @@ public sealed class AbCipDriver : IDriver, IReadable, IWritable, ITagDiscovery,
                 }
 
                 var runtime = await EnsureTagRuntimeAsync(device, def, cancellationToken).ConfigureAwait(false);
+
+                // Serialise Encode → Write → GetStatus against the shared runtime — the same cached
+                // Tag handle may be in use by a concurrent ReadAsync or poll loop (05/STAB-4).
+                var opLock = device.GetRuntimeLock(def.Name);
+                await opLock.WaitAsync(cancellationToken).ConfigureAwait(false);
+                int status;
+                try
+                {
                     runtime.EncodeValue(def.DataType, parsedPath?.BitIndex, w.Value);
                     await runtime.WriteAsync(cancellationToken).ConfigureAwait(false);
+                    status = runtime.GetStatus();
+                }
+                finally
+                {
+                    opLock.Release();
+                }
 
-                var status = runtime.GetStatus();
                 if (status != 0)
                 {
                     EvictRuntime(device, def.Name);