[Solved] How to get the list of functions in a dll -Unit testing

Sam

Hi I am working on a plugin example and trying to open a .dll file. The .dll file contains some methods, I need to display these methods/functions as nodes in a treeView. So how can i get the list of methods/function from a .dll file.

giesbert

That depends on the platform and compiler you are using.
As you are talking of dlls, I assume you are on windows.

Which compiler do you use?
Do you look for C-exported methods?
You have to read the dll export table and show that, but there is no Qt way for that.

MuldeR

On the Windows platform Dependency Walker is your friend:
http://www.dependencywalker.com/

But why do you need to list the exports of your plug-in DLL in your program at all?

Wouldn't it be much easier (and more robust/portable) to make something like a "myApp_initPlugin" function with a fixed name that each plug-in DLL is required to export?

That function, which is known beforehand, would then be called by the application to "load" the individual plug-in. It would "register" the plug-in to the application, announcing what functions the plug-in does provide...

(All plug-in API's I am aware of, including Qt's own Plug-in system, work in that way)

Sam

Hi,

Thanks for your time and suggestions :)

@Gerolf
I am working on windows platform and using MSVC 2010 compiler.

@MuldeR
I have a requirement where i need to test my libraries, so I am developing an application like "NUnit":http://www.google.ae/imgres?q=nUnit&um=1&hl=en&sa=N&biw=1486&bih=753&tbm=isch&tbnid=TIXxxfMFrlbhEM:&imgrefurl=http://www.dotnetjohn.com/articles.aspx?articleid=146&docid=4U1gLAxG0dFd9M&imgurl=http://www.dotnetjohn.com/Images/nunit2.JPG&w=756&h=512&ei=HCu7T4C7FcyWhQf04bH-CA&zoom=1&iact=hc&vpx=1057&vpy=365&dur=304&hovh=185&hovw=273&tx=108&ty=63&sig=113437160135027356483&page=2&tbnh=121&tbnw=179&start=28&ndsp=35&ved=1t:429,r:12,s:28,i:156 interface (for unit testing) where i use some plugin logic to create my dlls of my test classes and through the application/GUI we can load the dll file that displays the test functions in a tableView/treeView.

So now i am trying the same architecture proposed by you where each class will register itself to an interface/class and from the application i should be able to load the classes and its test functions.

So i need some idea about how to implement this. I got some information "here":http://qtcreator.blogspot.com/2009/10/running-multiple-unit-tests.html where the test classes register's itself.

Thanks for you time :)

MuldeR

Make a class like this whose only instance will live in the "main" application:

@class CPluginRegistry
{
/* ... */

public:
registerPlugin(CPluginBaseClass *plugin);

protected:
QMap<QString, CPluginBaseClass*> m_plugins;
}

void CPluginRegistry::registerPlugin(CPluginBaseClass plugin)
{
QString pluginName = plugin->getName();
plugin->getPluginCapabilities(); / application-specific, be creative here !!! */
m_plugins.insert(pluginName, plugin);
}@

The function that each plug-in DLL is required to export could look like:

@//The plug-in class
class CSomeConcretePluginClass : public CPluginBaseClass
{
/* all plug-in specific code goes here! */
}

//Public plug-in API
extern "C"
{
__decsplec(dllexport) void initPluginDLL(CPluginRegistry *registry)
{
CPluginBaseClass *myPlugin = new CSomeConcretePluginClass();
registry -> registerPlugin(myPlugin);
}
}@

The Code in the main app would look like this:
@CPluginRegistry g_registry = NULL;
QList<QLibraray> *g_libraries = NULL;

typedef void (*PluginInitFunc)(CPluginRegistry *registry);

void loadAllPlugins(void)
{
if(!g_registry) g_registry = new CPluginRegistry();
if(!g_libraries) g_libraries = new QList<QLibraray*>;

for(/* each .dll file in the "plugins" directory */)
{
    PluginInitFunc funcPtr = NULL;
    QLibraray *currentPlugin = new QLibraray(path_to_dll);
    
    if(funcPtr = (PluginInitFunc) currentPlugin->resolve("initPluginDLL"))
    {
        funcPtr(g_registry); //Call plugin "init" function to let plugin register itself!
        g_libraries << currentPlugin; //remember pointer for later clean-up!
    }
    else
    {
        delete currentPlugin; //Something went wrong :-(
    }
}

}@

Sam

Hi MulderR,
Thanks for the code. I'll have to try it and check.

As of now i am trying to register the test classes as provided "here":http://qtcreator.blogspot.com/2009/10/running-multiple-unit-tests.html

I have an interface

@class PluginInterface
{
public:
virtual QList<QObject*> LiTestList();
};

Q_DECLARE_INTERFACE(PluginInterface,"com.testing.PluginInterface 0.0.1")@

and another class that subclasses this interface class

@namespace AutoTest
{

typedef QList<QObject*> TestList;

inline TestList& testList()
{
    static TestList list;
    return list;
}

inline bool findObject(QObject* object)
{
    TestList& list = testList();
    if (list.contains(object))
    {
        return true;
    }
    foreach (QObject* test, list)
    {
        if (test->objectName() == object->objectName())
        {
            return true;
        }
    }
    return false;
}


inline void addTest(QObject* object)
{
    TestList& list = testList();
    if (!findObject(object))
    {
        list.append(object);
    }
}

}

template <class T>

class Test : public PluginInterface
{
Q_INTERFACES(PluginInterface)
public:
QList<QObject*> LiTestList()
{
return AutoTest::testList();
}

QSharedPointer<T> child;
Test(const QString& name) : child(new T)
{
    child->setObjectName(name);
    AutoTest::addTest(child.data());
}

};

Q_EXPORT_PLUGIN2(UnitTestingPlugin,Test) <-- This gives error!!!!!!!

#define DECLARE_TEST(className) static Test<className> t(#className);@

I want to create a .dll file so i use Q_EXPORT_PLUGIN2 macro, but this gives me the following error

@Error:
c:\testing\unittestingplugin\AutoTest.h:70: error: C2955: 'Test' : use of class template requires template argument list

c:\testing\unittestingplugin\AutoTest.h:70: error: C2512: 'Test' : no appropriate default constructor available

c:\testing\unittestingplugin\AutoTest.h:70: error: C2955: 'Test' : use of class template requires template argument list@

Please suggest what changes should i make.

Sam

Finally I got my code working with a different approach. I created a wrapper class that subclasses my interface and all my testClasses register's to the AutoTest. Also the interface class provided the list of testClasses.

Thanks for your time :)