From 4e15f3b68b7e05e4845c336ce94bc30ce9a4c654 Mon Sep 17 00:00:00 2001
From: Geoffrey McRae <geoff@hostfission.com>
Date: Mon, 17 Aug 2026 03:00:54 +1000
Subject: [PATCH] [idd] transport: stream writes to WC mappings

---
 .../transport/lgmp/CLGMPClipboardTransport.cpp      |  5 ++++-
 idd/LGIdd/transport/lgmp/CLGMPControl.cpp           | 13 +++++++++++--
 2 files changed, 15 insertions(+), 3 deletions(-)

diff --git a/idd/LGIdd/transport/lgmp/CLGMPClipboardTransport.cpp b/idd/LGIdd/transport/lgmp/CLGMPClipboardTransport.cpp
index 70b5a6b8..b7eecb9a 100644
--- a/idd/LGIdd/transport/lgmp/CLGMPClipboardTransport.cpp
+++ b/idd/LGIdd/transport/lgmp/CLGMPClipboardTransport.cpp
@@ -27,6 +27,7 @@
 #include "CDebug.h"
 #include "Seq.h"
 #include "WCCopy.h"
+#include "WCWrite.h"
 #include "transport/lgmp/CLGMPHost.h"
 
 #include <limits>
@@ -1745,8 +1746,10 @@ ClipboardChannelResult CLGMPClipboardTransport::SendData(
 
   memcpy(buffer.data, &message, sizeof(message));
   if (message.length)
-    memcpy(static_cast<uint8_t *>(buffer.data) + sizeof(message), data,
+    WCWrite::Copy(static_cast<uint8_t *>(buffer.data) + sizeof(message), data,
       message.length);
+
+  // Stream commit drains WC writes before publishing the producer cursor.
   status = lgmpHostStreamWriteCommit(
     m_hostToClientStream, &buffer, bytes);
   if (status == LGMP_OK)
diff --git a/idd/LGIdd/transport/lgmp/CLGMPControl.cpp b/idd/LGIdd/transport/lgmp/CLGMPControl.cpp
index 7a4305c0..2a5bcc1f 100644
--- a/idd/LGIdd/transport/lgmp/CLGMPControl.cpp
+++ b/idd/LGIdd/transport/lgmp/CLGMPControl.cpp
@@ -21,6 +21,7 @@
 #include "transport/lgmp/CLGMPControl.h"
 
 #include "CDebug.h"
+#include "WCWrite.h"
 
 #include <string.h>
 
@@ -30,6 +31,7 @@ static const uint32_t MAX_POINTER_SIZE =
   (uint32_t)(sizeof(KVMFRCursor) + (512 * 512 * 4));
 static const uint32_t POINTER_POSITION_SIZE =
   (uint32_t)sizeof(KVMFRCursor);
+static const size_t WC_WRITE_MIN_SIZE = 4 * 1024;
 
 static const struct LGMPQueueConfig POINTER_QUEUE_CONFIG =
 {
@@ -225,7 +227,12 @@ ControlResult CLGMPControl::SendCursor(
   if (hasShape)
   {
     if (size)
-      memcpy(cursor + 1, data, size);
+    {
+      if (size < WC_WRITE_MIN_SIZE)
+        memcpy(cursor + 1, data, size);
+      else
+        WCWrite::Copy(cursor + 1, data, size);
+    }
 
     cursor->hx     = (int8_t  )info.CursorShapeInfo.XHot;
     cursor->hy     = (int8_t  )info.CursorShapeInfo.YHot;
@@ -247,6 +254,7 @@ ControlResult CLGMPControl::SendCursor(
     flags |= CURSOR_FLAG_SHAPE;
   }
 
+  WCWrite::Flush();
   const LGMP_STATUS status =
     lgmpHostQueuePost(m_pointerQueue, flags, mem);
   if (status == LGMP_OK)
@@ -292,9 +300,10 @@ ControlResult CLGMPControl::SendColorTransform(
       output->flags |= KVMFR_COLOR_TRANSFORM_LUT;
     memcpy(output->matrix, transform->matrix, sizeof(output->matrix));
     output->scalar = transform->scalar;
-    memcpy(output->lut, transform->lut, sizeof(output->lut));
+    WCWrite::Copy(output->lut, transform->lut, sizeof(output->lut));
   }
 
+  WCWrite::Flush();
   const LGMP_STATUS status = lgmpHostQueuePost(m_pointerQueue,
     CURSOR_FLAG_COLOR_TRANSFORM, mem);
   if (status == LGMP_OK)