[PATCH v6 5/6] dlls/sane.ds: Implement DG_CONTROL/DAT_PENDINGXFERS/MSG_GET based on remainingImages counter

[Bernd Herd]

From: Bernd Herd

---
 dlls/sane.ds/ds_ctrl.c | 30 +++++++++++++++++++++++++++++-
 1 file changed, 29 insertions(+), 1 deletion(-)

diff --git a/dlls/sane.ds/ds_ctrl.c b/dlls/sane.ds/ds_ctrl.c
index acececba685..990387d3a86 100644
--- a/dlls/sane.ds/ds_ctrl.c
+++ b/dlls/sane.ds/ds_ctrl.c
@@ -259,11 +259,39 @@ TW_UINT16 SANE_PendingXfersGet (pTW_IDENTITY pOrigin,
         twRC = TWRC_FAILURE;
         activeDS.twCC = TWCC_SEQERROR;
     }
+    else if (activeDS.currentState < 6)
+    {
+        /* We have not yet started scanning */
+        pPendingXfers->Count = activeDS.capXferCount;
+        twRC = TWRC_SUCCESS;
+        activeDS.twCC = TWCC_SUCCESS;
+
+    }
+    else if (activeDS.remainingImages != -1)
+    {
+        /* The application gave us a counter with CAP_XFERCOUNT */
+        pPendingXfers->Count = activeDS.remainingImages;
+        twRC = TWRC_SUCCESS;
+        activeDS.twCC = TWCC_SUCCESS;
+    }
+    else if (activeDS.currentState == 7)
+    {
+        /* We are already scanning a frame, so there obviously is one */
+        pPendingXfers->Count = -1;
+        twRC = TWRC_SUCCESS;
+        activeDS.twCC = TWCC_SUCCESS;
+    }
     else
     {
         pPendingXfers->Count = -1;
-        if (SANE_CALL( start_device, NULL ))
+        if (SANE_Start())
+        {
+            /* No more frames... tell the application */
             pPendingXfers->Count = 0;
+            activeDS.currentState = 5;
+            SANE_Cancel();
+            SANE_Notify(MSG_CLOSEDSREQ);
+        }
         twRC = TWRC_SUCCESS;
         activeDS.twCC = TWCC_SUCCESS;
     }