[DynInst_API:] query

[shruthi tv <tv.shruthi@xxxxxxxxx>]

Hi,

We are developing the dynamic instrumentation tool using dyninst API's.

Please help me.

Â

In the following code I am attaching to process,inserting the printf snippet and detaching from it. Again I am reattaching to the same process for the sake of deleting the snippet inserted previously.

But I am not able to delete the snippet. Is there any possible ways to delete the snippet after reattaching to it.

void usage() {

    cout<<"Please enter the pid and function name"<<endl;

}

int main(int argc , char *argv[])

{

    BPatch bpatch;

    int pid;

    bool ret;

    if (argc != 3) {

        usage();

        exit(1);

    }

    pid=atoi(argv[1]);

    cout<<"The attached pid is "<<pid<<endl;

    cout<<"the function name is "<<argv[2]<<endl;

    BPatch_process *appProc = bpatch.processAttach("",pid);

    BPatch_image *img = appProc->getImage();

    bpatch.setTrampRecursive(true);

    std::vector<BPatch_function *> printFuncs;

    img->findFunction(argv[2],printFuncs);

    if (printFuncs.size() == 0) {

        cout<<"Unable to find function "<<argv[2]<<endl;

        return -1;

    } else {

        Âstd::vector<BPatch_point *> *points;

        std::vector<BPatch_snippet *> printArgs;

        BPatch_snippet *fmt = new BPatch_constExpr("hello world\n");

        printArgs.push_back(fmt);

        std::vector<BPatch_function *> printfFuncs;

        img->findFunction("printf", printfFuncs);

        BPatch_funcCallExpr printfCall(*(printfFuncs[0]), printArgs);

        points = printFuncs[0]->findPoint(BPatch_entry);

        if ((*points).size() == 0) {

            return false;

        } else {

Âcout<<"Got the points "<<endl;

        }

        BPatchSnippetHandle *ptr;

        ptr=appProc->insertSnippet(printfCall, *points);

        if(!ptr)

        {

            cout<<"Failed to insert the snippet"<<endl;

        } else {

            cout<<"Snippet is inserted successfully"<<endl;

        }

   }

    appProc->detach(true);

    cout<<"Done."<<endl;

    cout<<"Reattaching will be done again for deletion"<<endl;

    BPatch_process *appProc1 = bpatch.processAttach("", pid);

    BPatch_image *img1 = appProc1->getImage();

    if(img1) {

        cout<<"Successfully got the image again"<<endl;

    } else {

        cout<<"failed to get the image"<<endl;

    }

    std::vector<BPatch_function *> printFuncs1;

    img->findFunction(argv[2],printFuncs1);

    if (printFuncs1.size() == 0) {

        cout<<"Unable to find function "<<argv[2]<<endl;

        return -1;

    } else {

        Âstd::vector<BPatch_point *> *points1;

        std::vector<BPatch_function *> printfFuncs1;

        img->findFunction("printf", printfFuncs1);

        points1 = printFuncs1[0]->findPoint(BPatch_entry);

        if ((*points1).size() == 0) {

            return false;

        } else {

            cout<<"Got the points 2nd time"<<endl;

        }

        BPatch_point pt=*(*points1)[0];

        BPatch_Vector<BPatchSnippetHandle *> childSnippets = pt.getCurrentSnippets(BPatch_callBefore);

        if(childSnippets.size()==0){

Âcout<<" No snippets were found "<<endl;

        } else {

            cout<<"The snippet size is "<<childSnippets.size()<<endl;

        }

        sleep(50);

        Âbool ret=appProc->deleteSnippet(childSnippets[0]);

       if(ret)

       {

            cout<<"The snippet is deleted"<<endl;

       } else {

           cout<<"Failed to delete the snippet"<<endl;

       }

        BPatch_point po=*(*points1)[0];

        bool check=appProc1->removeFunctionCall(po);

        if(check) {

            cout<<"success"<<endl;

        } else {

            cout<<"failure"<<endl;

        }

    }

    appProc1->detach(true);

    cout<<"Done for second time."<<endl;

    return 0;

}

Thanks,

Shruthi