ndb - bug#21941

  Fix so that scans closed before execute are removed from "scans to send list"


ndb/include/ndbapi/NdbTransaction.hpp:
  Fix so that scans closed before execute are removed from "scans to send list"
ndb/src/ndbapi/NdbScanOperation.cpp:
  Fix so that scans closed before execute are removed from "scans to send list"
ndb/src/ndbapi/NdbTransaction.cpp:
  Fix so that scans closed before execute are removed from "scans to send list"

ndb/include/ndbapi/NdbTransaction.hpp

@@ -657,6 +657,9 @@ private:
   // Release all cursor operations in connection
   void releaseOps(NdbOperation*);	
   void releaseScanOperations(NdbIndexScanOperation*);	
+  bool releaseScanOperation(NdbIndexScanOperation** listhead,
+			    NdbIndexScanOperation** listtail,
+			    NdbIndexScanOperation* op);
   void releaseExecutedScanOperation(NdbIndexScanOperation*);
   
   // Set the transaction identity of the transaction

ndb/src/ndbapi/NdbScanOperation.cpp

@@ -678,9 +678,27 @@ void NdbScanOperation::close(bool forceSend, bool releaseOp)
   theNdbCon = NULL;
   m_transConnection = NULL;
 
-  if (releaseOp && tTransCon) {
+  if (tTransCon) 
+  {
     NdbIndexScanOperation* tOp = (NdbIndexScanOperation*)this;
-    tTransCon->releaseExecutedScanOperation(tOp);
+
+    bool ret = true;
+    if (theStatus != WaitResponse)
+    {
+      /**
+       * Not executed yet
+       */
+      ret = 
+	tTransCon->releaseScanOperation(&tTransCon->m_theFirstScanOperation,
+					&tTransCon->m_theLastScanOperation,
+					tOp);
+    }
+    else if (releaseOp)
+    {
+      ret = tTransCon->releaseScanOperation(&tTransCon->m_firstExecutedScanOp,
+					    0, tOp);
+    }
+    assert(ret);
   }
   
   tCon->theScanningOp = 0;

ndb/src/ndbapi/NdbTransaction.cpp

@@ -978,27 +978,58 @@ void
 NdbTransaction::releaseExecutedScanOperation(NdbIndexScanOperation* cursorOp)
 {
   DBUG_ENTER("NdbTransaction::releaseExecutedScanOperation");
-  DBUG_PRINT("enter", ("this=0x%x op=0x%x", (UintPtr)this, (UintPtr)cursorOp))
+  DBUG_PRINT("enter", ("this=0x%x op=0x%x", (UintPtr)this, (UintPtr)cursorOp));
   
-  // here is one reason to make op lists doubly linked
-  if (m_firstExecutedScanOp == cursorOp) {
-    m_firstExecutedScanOp = (NdbIndexScanOperation*)cursorOp->theNext;
-    cursorOp->release();
-    theNdb->releaseScanOperation(cursorOp);
-  } else if (m_firstExecutedScanOp != NULL) {
-    NdbIndexScanOperation* tOp = m_firstExecutedScanOp;
-    while (tOp->theNext != NULL) {
-      if (tOp->theNext == cursorOp) {
-        tOp->theNext = cursorOp->theNext;
-        cursorOp->release();
-        theNdb->releaseScanOperation(cursorOp);
+  releaseScanOperation(&m_firstExecutedScanOp, 0, cursorOp);
+  
+  DBUG_VOID_RETURN;
+}//NdbTransaction::releaseExecutedScanOperation()
+
+bool
+NdbTransaction::releaseScanOperation(NdbIndexScanOperation** listhead,
+				     NdbIndexScanOperation** listtail,
+				     NdbIndexScanOperation* op)
+{
+  if (* listhead == op)
+  {
+    * listhead = (NdbIndexScanOperation*)op->theNext;
+    if (listtail && *listtail == op)
+    {
+      assert(* listhead == 0);
+      * listtail = 0;
+    }
+      
+  }
+  else
+  {
+    NdbIndexScanOperation* tmp = * listhead;
+    while (tmp != NULL)
+    {
+      if (tmp->theNext == op)
+      {
+	tmp->theNext = (NdbIndexScanOperation*)op->theNext;
+	if (listtail && *listtail == op)
+	{
+	  assert(op->theNext == 0);
+	  *listtail = tmp;
+	}
 	break;
       }
-      tOp = (NdbIndexScanOperation*)tOp->theNext;
+      tmp = (NdbIndexScanOperation*)tmp->theNext;
     }
+    if (tmp == NULL)
+      op = NULL;
   }
-  DBUG_VOID_RETURN;
-}//NdbTransaction::releaseExecutedScanOperation()
+  
+  if (op != NULL)
+  {
+    op->release();
+    theNdb->releaseScanOperation(op);
+    return true;
+  }
+  
+  return false;
+}
 
 /*****************************************************************************
 NdbOperation* getNdbOperation(const char* aTableName);