[host] improve mouse sync with the client

host/Capture/DXGI.cpp

@@ -350,20 +350,20 @@ size_t DXGI::GetMaxFrameSize()
   return (m_width * m_height * 4);
 }
 
-GrabStatus Capture::DXGI::Capture()
+unsigned int Capture::DXGI::Capture()
 {
   if (!m_initialized)
     return GRAB_STATUS_ERROR;
 
   CursorInfo cursor = { 0 };
-  bool cursorUpdated = false;
   DXGI_OUTDUPL_FRAME_INFO frameInfo;
   IDXGIResourcePtr res;
+  unsigned int ret;
 
   HRESULT status;
   for (int retryCount = 0; retryCount < 2; ++retryCount)
   {
-    GrabStatus ret = ReleaseFrame();
+    ret = ReleaseFrame();
     if (ret != GRAB_STATUS_OK)
       return ret;
 
@@ -396,7 +396,7 @@ GrabStatus Capture::DXGI::Capture()
         m_lastCursorX != frameInfo.PointerPosition.Position.x ||
         m_lastCursorY != frameInfo.PointerPosition.Position.y
       ) {
-        cursorUpdated = true;
+        ret |= GRAB_STATUS_CURSOR;
         cursor.hasPos = true;
         cursor.x      = m_lastCursorX = frameInfo.PointerPosition.Position.x;
         cursor.y      = m_lastCursorY = frameInfo.PointerPosition.Position.y;
@@ -404,12 +404,24 @@ GrabStatus Capture::DXGI::Capture()
 
       if (m_lastMouseVis != frameInfo.PointerPosition.Visible)
       {
-        cursorUpdated  = true;
+        ret |= GRAB_STATUS_CURSOR;
         m_lastMouseVis = frameInfo.PointerPosition.Visible;
       }
 
       cursor.visible = m_lastMouseVis == TRUE;
     }
+    else
+    {
+      // always report the mouse position to prevent the guest losing sync (ie: dragging windows)
+      POINT curPos;
+      if (GetCursorPos(&curPos) && (curPos.x != m_lastCursorX || curPos.y != m_lastCursorY))
+      {
+        ret |= GRAB_STATUS_CURSOR;
+        cursor.hasPos = true;
+        cursor.x = m_lastCursorX = curPos.x;
+        cursor.y = m_lastCursorY = curPos.y;
+      }
+    }
 
     // if the pointer shape has changed
     if (frameInfo.PointerShapeBufferSize > 0)
@@ -442,7 +454,7 @@ GrabStatus Capture::DXGI::Capture()
 
       buf->pointerSize = 0;
       cursor.shape     = buf;
-      cursorUpdated    = true;
+      ret             |= GRAB_STATUS_CURSOR;
 
       DXGI_OUTDUPL_POINTER_SHAPE_INFO shapeInfo;
       status = m_dup->GetFramePointerShape(buf->bufferSize, buf->buffer, &buf->pointerSize, &shapeInfo);
@@ -467,7 +479,7 @@ GrabStatus Capture::DXGI::Capture()
       cursor.pitch = shapeInfo.Pitch;
     }
 
-    if (cursorUpdated)
+    if (ret & GRAB_STATUS_CURSOR)
     {
       // push the cursor update into the queue
       EnterCriticalSection(&m_cursorCS);
@@ -479,20 +491,23 @@ GrabStatus Capture::DXGI::Capture()
     if (frameInfo.LastPresentTime.QuadPart == 0)
     {
       // if there is nothing to update, just start again
-      if (!cursorUpdated)
+      if (!ret)
       {
         --retryCount;
         continue;
       }
 
       res = NULL;
-      return GRAB_STATUS_CURSOR;
+      ret |= GRAB_STATUS_OK;
+      return ret;
     }
 
     // success, break out of the retry loop
     break;
   }
 
+  ret |= GRAB_STATUS_FRAME;
+
   // ensure we have a frame
   if (!m_releaseFrame)
   {
@@ -508,7 +523,8 @@ GrabStatus Capture::DXGI::Capture()
     return GRAB_STATUS_ERROR;
   }
 
-  return GRAB_STATUS_OK;
+  ret |= GRAB_STATUS_OK;
+  return ret;
 }
 
 GrabStatus Capture::DXGI::ReleaseFrame()

host/Capture/DXGI.h

@@ -58,7 +58,7 @@ namespace Capture
 
     enum FrameType GetFrameType();
     size_t GetMaxFrameSize();
-    GrabStatus Capture();
+    unsigned int Capture();
     GrabStatus GetFrame (struct FrameInfo  & frame );
     bool GetCursor(CursorInfo & cursor);
     void FreeCursor(CursorInfo & cursor);

host/ICapture.h

@@ -54,11 +54,12 @@ struct FrameInfo
 
 enum GrabStatus
 {
-  GRAB_STATUS_OK,
-  GRAB_STATUS_TIMEOUT,
-  GRAB_STATUS_REINIT,
-  GRAB_STATUS_CURSOR,
-  GRAB_STATUS_ERROR
+  GRAB_STATUS_OK      = 1,
+  GRAB_STATUS_TIMEOUT = 2,
+  GRAB_STATUS_REINIT  = 4,
+  GRAB_STATUS_CURSOR  = 8,
+  GRAB_STATUS_FRAME   = 16,
+  GRAB_STATUS_ERROR   = 32
 };
 
 typedef std::vector<const char *> CaptureOptions;
@@ -74,7 +75,7 @@ public:
   virtual bool ReInitialize() = 0;
   virtual enum FrameType GetFrameType() = 0;
   virtual size_t GetMaxFrameSize() = 0;
-  virtual enum GrabStatus Capture() = 0;
+  virtual unsigned int Capture() = 0;
   virtual enum GrabStatus GetFrame(struct FrameInfo & frame) = 0;
   virtual bool GetCursor(CursorInfo & cursor) = 0;
   virtual void FreeCursor(CursorInfo & cursor) = 0;

host/Service.cpp

@@ -193,87 +193,88 @@ bool Service::Process()
     INTERLOCKED_AND8(flags, ~(KVMFR_HEADER_FLAG_RESTART));
   }
 
-  GrabStatus result;
-
+  unsigned int status;
   bool ok         = false;
-  bool cursorOnly = false;
   bool repeat     = false;
+
   for(int i = 0; i < 2; ++i)
   {
-    // capture a frame of data
-    switch (m_capture->Capture())
+    status = m_capture->Capture();
+    if (status & GRAB_STATUS_OK)
     {
-      case GRAB_STATUS_OK:
-        ok = true;
-        break;
-
-      case GRAB_STATUS_TIMEOUT:
-        if (m_haveFrame)
-        {
-          ok     = true;
-          repeat = true;
-          break;
-        }
-
-        // capture timeouts are not errors
-        --i;
-        continue;
-
-      case GRAB_STATUS_CURSOR:
-        ok         = true;
-        cursorOnly = true;
-        break;
-
-      case GRAB_STATUS_ERROR:
-        DEBUG_ERROR("Capture failed");
-        return false;
-
-      case GRAB_STATUS_REINIT:
-        DEBUG_INFO("ReInitialize Requested");
-
-        INTERLOCKED_OR8(flags, KVMFR_HEADER_FLAG_PAUSED);
-        if(WTSGetActiveConsoleSessionId() != m_consoleSessionID)
-        {
-          DEBUG_INFO("User switch detected, waiting to regain control");
-          while (WTSGetActiveConsoleSessionId() != m_consoleSessionID)
-            Sleep(100);
-        }
-
-        while (!m_capture->CanInitialize())
-          Sleep(100);
-
-        if (!m_capture->ReInitialize())
-        {
-          DEBUG_ERROR("ReInitialize Failed");
-          return false;
-        }
-
-        if (m_capture->GetMaxFrameSize() > m_frameSize)
-        {
-          DEBUG_ERROR("Maximum frame size of %zd bytes excceds maximum space available", m_capture->GetMaxFrameSize());
-          return false;
-        }
-
-        INTERLOCKED_AND8(flags, ~KVMFR_HEADER_FLAG_PAUSED);
-
-        // re-init request should not count towards a failure to capture
-        --i;
-        continue;
+      ok = true;
+      break;
     }
 
-    if (ok)
-      break;
+    if (status & GRAB_STATUS_TIMEOUT)
+    {
+      if (m_haveFrame)
+      {
+        ok     = true;
+        repeat = true;
+        break;
+      }
+
+      // timeouts should not count towards a failure to capture
+      --i;
+      continue;
+    }
+
+    if (status & GRAB_STATUS_ERROR)
+    {
+      DEBUG_ERROR("Capture failed, retrying");
+      continue;
+    }
+
+    if (status & GRAB_STATUS_REINIT)
+    {
+      DEBUG_INFO("ReInitialize Requested");
+
+      INTERLOCKED_OR8(flags, KVMFR_HEADER_FLAG_PAUSED);
+      if (WTSGetActiveConsoleSessionId() != m_consoleSessionID)
+      {
+        DEBUG_INFO("User switch detected, waiting to regain control");
+        while (WTSGetActiveConsoleSessionId() != m_consoleSessionID)
+          Sleep(100);
+      }
+
+      while (!m_capture->CanInitialize())
+        Sleep(100);
+
+      if (!m_capture->ReInitialize())
+      {
+        DEBUG_ERROR("ReInitialize Failed");
+        return false;
+      }
+
+      if (m_capture->GetMaxFrameSize() > m_frameSize)
+      {
+        DEBUG_ERROR("Maximum frame size of %zd bytes excceds maximum space available", m_capture->GetMaxFrameSize());
+        return false;
+      }
+
+      INTERLOCKED_AND8(flags, ~KVMFR_HEADER_FLAG_PAUSED);
+
+      // re-init request should not count towards a failure to capture
+      --i;
+      continue;
+    }
+
+    DEBUG_ERROR("Capture interface returned an unexpected result");
+    return false;
   }
 
+
   if (!ok)
   {
     DEBUG_ERROR("Capture retry count exceeded");
     return false;
   }
 
-  SetEvent(m_cursorEvent);
+  if (status & GRAB_STATUS_CURSOR)
+    SetEvent(m_cursorEvent);
 
-  if (!cursorOnly)
+  if (status & GRAB_STATUS_FRAME)
   {
     volatile KVMFRFrame * fi = &(m_shmHeader->frame);
  
@@ -284,7 +285,7 @@ bool Service::Process()
       frame.buffer     = m_frame[m_frameIndex];
       frame.bufferSize = m_frameSize;
 
-      result = m_capture->GetFrame(frame);
+      GrabStatus result = m_capture->GetFrame(frame);
       if (result != GRAB_STATUS_OK)
       {
         DEBUG_INFO("GetFrame failed");