FIX: CColumnsInfo Reference Count Leak in MSDAORA REF CURSOR When You Retrieve Data from an Oracle Function

MDAC 2.7

   Date         Time   Version            Size    File name
   --------------------------------------------------------------
   22-May-2002  22:03  2.70.8722.0       221,184  Msdaora.dll      

				

MDAC 2.7 SP1

  
   Date         Time   Version            Size    File name
   --------------------------------------------------------------
   05-Mar-2003  18:07  2.71.9031.34      221,184  Msdaora.dll      
			

MDAC 2.8

  
   Date         Time   Version            Size    File name
   --------------------------------------------------------------
   20-Nov-2003  11:55  2.80.1026.0      225,280  Msdaora.dll      
			

Steps to reproduce the problem

1. Set up an appropriate Oracle client.
2. In Microsoft Visual C ++ 6.0, create an empty Windows Console Application.
3. Add a new C++ Source file to the project.
4. Add the following ATL OLE DB client code to the application:

   #define _ATL_STATIC_REGISTRY 
   #define _ATL_DEBUG_QI   
   #define _ATL_DEBUG_INTERFACES
   
   #include <atldbcli.h>   // The main ATL consumer header
   #include <conio.h>		// getch()
   #include <stdio.h>		// printf()
   
   // Second Accessor
   class CLeakTestAccessor1
   {
   public:
   	DEFINE_COMMAND(CLeakTestAccessor1, _T("CREATE TABLE TestTable (Int INTEGER, Str VARCHAR2(256));"))
   };
   
   // Third Accessor
   class CLeakTestAccessor2
   {
   public:
   	DEFINE_COMMAND(CLeakTestAccessor2, _T("INSERT INTO TestTable (Int, Str) VALUES (5, 'This is a test.');"))
   };
   
   // Fourth Accessor
   class CLeakTestAccessor3
   {
   public:
   	DEFINE_COMMAND(CLeakTestAccessor3, _T("CREATE OR REPLACE PACKAGE Test AS \ 
   		TYPE TestCur IS REF CURSOR;\ 
   		function LeakTest(p_Num IN INTEGER, p_Cursor OUT TestCur) return integer;\ 
   		procedure NoLeakTest(p_Cursor OUT TestCur, p_Num IN INTEGER); \ 
   		END Test;"))
   };
   
   // Fifth Accessor
   class CLeakTestAccessor4
   {
   public:
   
   	DEFINE_COMMAND(CLeakTestAccessor4, _T("CREATE OR REPLACE PACKAGE BODY Test AS  \ 
   		function LeakTest(p_Num IN INTEGER, p_Cursor OUT TestCur) return integer as \ 
   		begin \ 
   		OPEN p_Cursor FOR \ 
   		SELECT Int, Str FROM TestTable; \ 
   		return 0; \ 
   		end LeakTest;\ 
   		procedure NoLeakTest(p_Cursor OUT TestCur, p_Num IN INTEGER) as \ 
   		begin \ 
   		OPEN p_Cursor FOR \ 
   		SELECT Int, Str FROM TestTable; \ 
   		end; \ 
   		END Test;"))
   };
   
   // Initialize the package and create the re-quite table and data
   HRESULT DoInit()
   {
   	CDataSource ds;
   	CSession sess;
   	CCommand<CAccessor<CLeakTestAccessor1>,CNoRowset> cmd1;
   	CCommand<CAccessor<CLeakTestAccessor2>,CNoRowset> cmd2;
   	CCommand<CAccessor<CLeakTestAccessor3>,CNoRowset> cmd3;
   	CCommand<CAccessor<CLeakTestAccessor4>,CNoRowset> cmd4;
   	HRESULT hr;
   
   	try
   	{
   		hr = ds.OpenFromInitializationString(L"Provider=MSDAORA.1;Data Source=myServer;Password=myPassword;User ID=myUserID");
   		hr = sess.Open(ds);
   		ds.Close();
   		hr = cmd1.Open(sess);
   		cmd1.Close();
   		cmd1.ReleaseCommand();
   		cmd1.m_spCommand.Attach(NULL);
   		hr = cmd2.Open(sess);
   		cmd2.Close();
   		cmd2.ReleaseCommand();
   		cmd2.m_spCommand.Attach(NULL);
   		hr = cmd3.Open(sess);
   		cmd3.Close();
   		cmd3.ReleaseCommand();
   		cmd3.m_spCommand.Attach(NULL);
   		hr = cmd4.Open(sess);
   		cmd4.Close();
   		cmd4.ReleaseCommand();
   		cmd4.m_spCommand.Attach(NULL);
   	}
   	catch(...)
   	{
   		printf("\nAn exception has occurred in DoInit()...");
   		AtlTrace("\nAn exception has occurred in DoInit()...");
   		printf("\n");
   		AtlTrace("\n");
   		AtlTraceErrorRecords(hr);
   		return E_FAIL;
   	}
   	return hr;
   }
   
   
   // Main Accessor
   class CLeakTestAccessor
   {
   public:
   
   	LONG m_RETURNVALUE;
   	LONG m_lNum;
   	LONG m_lInt;
   	TCHAR m_szStr[257];
   
   	BEGIN_PARAM_MAP(CLeakTestAccessor)
   		SET_PARAM_TYPE(DBPARAMIO_OUTPUT)
   		COLUMN_ENTRY(1, m_RETURNVALUE)
   		SET_PARAM_TYPE(DBPARAMIO_INPUT)
   		COLUMN_ENTRY(2, m_lNum)
   	END_PARAM_MAP()
   
   	DEFINE_COMMAND(CLeakTestAccessor, _T("{ ? = call Test.LeakTest( {resultset 0, p_Cursor},?) }"))
   
   	void ClearRecord()
   	{
   		memset(this, 0, sizeof(*this));
   	}
   
   };
   
   // The main function
   void main(void)
   {
   	HRESULT hr;
   	long lLoopCtr = 0;
   
   	try
   	{
   		// Initialize COM libraries
   		CoInitialize(NULL);
   
   		printf("\nStarting the MSDAORA Leak Test Application...");
   		AtlTrace("\nStarting the MSDAORA Leak Test Application...");
   		// Perform the Initiailization
   		hr = DoInit();
   		if (SUCCEEDED(hr))
   		{
   			printf("\nLooping through 1000 times...");
   			AtlTrace("\nLooping through 1000 times...");
   			for (lLoopCtr =0; lLoopCtr < 1000; lLoopCtr++)
   			{
   				// Open the Connection
   				CDataSource ds;
   				hr = ds.OpenFromInitializationString(L"Provider=MSDAORA.1;Data Source=myServer;Password=myPassword;User ID=myUserID");
   				if (SUCCEEDED(hr))
   				{
   					// Open the session
   					CSession sess;
   					hr = sess.Open(ds);
   					for (int i=0; i<1000; i++)
   					{
   						if (SUCCEEDED(hr))
   						{
   							CCommand<CAccessor<CLeakTestAccessor> > cmd;
   							cmd.m_lNum = 2;
   							// Open the Command
   							hr = cmd.Open(sess);
   							if (SUCCEEDED(hr))
   							{
   									hr = cmd.MoveNext();
   									while (hr == S_OK)
   										hr = cmd.MoveNext();
   							} // end if
   							cmd.Close();
   							cmd.ReleaseCommand();
   						}  // end if 
   						ds.Close();
   					} // end for
   				} // end if
   			} // end for
   		}
   		printf("Press any key to continue...");
   		AtlTrace("Press any key to continue...");
   		getch();
   	}
   	catch(...)
   	{
   		AtlTrace("\nAn exception has occurred in main()...");
   		printf("\nAn exception has occurred in main()...");
   		AtlTrace("\n");
   		printf("\n");
   		AtlTraceErrorRecords(hr);
   	}
   }
   
    
   						

5. Modify the connection string, the Data Source, the User ID, and the Password parameters as appropriate for your environment.
6. Compile the application.
7. Start Performance Monitor.
8. Run the application. Notice that the Mem Usage counter for this application in Performance Monitor starts to increase.
9. Stop the application.
10. Install the hotfix.
11. Run the application again, and notice that there is no memory leak.