Step 3 - Add a worker thread

Add a worker thread

In AvgOpt.h, add an instance of ThreadManager.:

...
#include <xlserialize.h>
#include <xlmenu.h>
#include "ThreadManager.h" 
#include "data_avgopt.h"
...

class CAvgOptApp : public CXllApp
{
public:
    CAvgOptApp();

// Names
public:
    static LPCSTR m_pszDefName;

// Data
    AvgOptDataCache m_cacheAvgOpt;

// Operations
    void ClearCache();

// Multiple thread manager              
    psl::ThreadManager m_threadManager; 
    static size_t m_maxThreads;         

// Menu
    CXlMenu m_menu;

...
};

In AvgOpt.cpp, amend the constructor, so that the ThreadManager instance is initialized.

/////////////////////////////////////////////////////////////////////////////
// CAvgOptApp construction

size_t CAvgOptApp::m_maxThreads = 4; 

CAvgOptApp::CAvgOptApp()
: m_threadManager(m_maxThreads)      
{
    // TODO: add construction code here,
    // Place all significant initialization in InitInstance
}

Amend the OnXllOpenEx() and OnXllCose() event handlers, so that the ThreadManager is initialized and terminated.

BOOL CAvgOptApp::OnXllOpenEx()
{
    // Set up menu
    m_menu.SetTexts("&AvgOpt");
    m_menu.AddItem("&Clear cache", "AvgOptClearCache");
    m_menu.Create();

    // Start the thread manager                             
    if (!m_threadManager.Init())                            
    {                                                       
        XlMessageBox("Failed to initialize thread manager", 
              XlMessageBoxTypeExclamation);                 
        return FALSE;                                       
    }                                                       

    return TRUE;
}

void CAvgOptApp::OnXllClose()
{
    // Stop all threads                                     
    m_threadManager.Term();                                 

    // Delete menu
    m_menu.Destroy();
}

Worker thread

Add a new function to be called by worker threads:

void __stdcall AvgOptValue_threadfn(void* pvData)
{
    AvgOptData* args = (AvgOptData*)pvData;

    args->Evaluate();
    args->done = true;
    psl::XllRtdSharedData::IncrementChannelSeqNum("AvgOpt");
}

The following points are of interest in the worker thread function:

• The __stdcall calling convention is required for the worker thread.
• The argument to the function is the pointer originally passed to ThreadManager:: StartThread().
• The worker thread evaluates the data object, and thereby (eventually) populates the outputs of the data object.
• The worker thread sets the done flag to true, indicating to the add-in function that the outputs are now valid.
• The worker thread uses the XllRtdSharedData interface to increment the sequence number of the named channel "AvgOpt", and thereby informs the RTD module that new data is available for this function.

Next, we will modify the add-in function so that it passes all the work of calculation to a worker thread.

Next: Step 4 - Modify add-in function >>