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About python gdb scirpt support

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ollydbg:
Hi, yesterday, I have found a new way to support the gdb debugging in cb. Here is the brief introduction.
GDB with Python support

If we add another python wxStuff support, note that the original file is:
wxStuff support python script

If you use wxWidgets 2.8.x version, you need to change this py file to some thin like:


--- Code: ---class wxStringPrinter:
    def __init__(self, val):
        self.val = val

    def to_string(self):
return self.val['m_pchData'].string()
        #return '"' + self.val['m_impl']['_M_dataplus']['_M_p'].string() + '"'

    def display_hint(self):
        return 'string'

--- End code ---

Note that, if you use 2.9.x version of wxWidgets, you can use the original py script. More details can be found in:
wxBlog: Pretty printing wxStuff in gdb

To load both the stl_print and wx_print python scirpt, I create a my.gdb file, like:

--- Code: ---python
import sys
sys.path.insert(0, 'C:\stl_python')
from libstdcxx.v6.printers import register_libstdcxx_printers
register_libstdcxx_printers (None)
execfile("f:/cb/wx_print.py")
end

--- End code ---

Then, I suggest that you don't need the gdb.script to register several types, so, it is saft to comment them, because python scirpt works better!!!

Open the file like F:\cb\cb_ccbranch\src\output\share\CodeBlocks\scripts\gdb_types.script

Then, comment the file like:

--- Code: ---// Registers new types with driver
function RegisterTypes(driver)
{
//    signature:
//    driver.RegisterType(type_name, regex, eval_func, parse_func);

    // wxString
    // driver.RegisterType(
        // _T("wxString"),
        // _T("[^[:alnum:]_]*wxString[^[:alnum:]_]*"),
        // _T("Evaluate_wxString"),
        // _T("Parse_wxString")
    // );

    // STL String
    // driver.RegisterType(
        // _T("STL String"),
        // _T("[^[:alnum:]_]*string[^[:alnum:]_]*"),
        // _T("Evaluate_StlString"),
        // _T("Parse_StlString")
    // );

    // STL Vector
    // driver.RegisterType(
        // _T("STL Vector"),
        // _T("[^[:alnum:]_]*vector<.*"),
        // _T("Evaluate_StlVector"),
        // _T("Parse_StlVector")
    // );

    Log(_T("Registering types for the debugger."));
}

--- End code ---

And finally, you need to add the gdb scirpt file in the debugger starting command, like:


That's all, you can enjoying debugging!!! :D

ollydbg:
Here is the test code:

--- Code: ---#include <iostream>
#include <vector>
#include <string>

using namespace std;

main()
{
   vector<string> SS;

   SS.push_back("The number is 10");
   SS.push_back("The number is 20");
   SS.push_back("The number is 30");

   cout << "Loop by index:" << endl;

   int ii;
   for(ii=0; ii < SS.size(); ii++)
   {
      cout << SS[ii] << endl;
   }

   cout << endl << "Constant Iterator:" << endl;

   vector<string>::const_iterator cii;
   for(cii=SS.begin(); cii!=SS.end(); cii++)
   {
      cout << *cii << endl;
   }

   cout << endl << "Reverse Iterator:" << endl;

   vector<string>::reverse_iterator rii;
   for(rii=SS.rbegin(); rii!=SS.rend(); ++rii)
   {
      cout << *rii << endl;
   }

   cout << endl << "Sample Output:" << endl;

   cout << SS.size() << endl;
   cout << SS[2] << endl;

   swap(SS[0], SS[2]);
   cout << SS[2] << endl;
}

--- End code ---

You can add the variable SS to watch window, and see how good it works. and it works really badly if python gdb scirpt is not enabled.
see the screen shot below:


[attachment deleted by admin]

reckless:
nice one olly :)

gonna try this out.

ollydbg:
there is only one problems when using the python script for wxStuff and stl.
When we are using "info local" command to let the gdb show all the local variables, we may meet some problem.
eg:


--- Code: ---#include <wx/wx.h>
#include <string>
#include <map>
#include <list>
#include <stack>
#include <vector>

int main() {
    int x;
    wxString wxStr(L"wxString");
    wxStr += L" Value";
    std::string stdStr("std::string");
    stdStr.append(" value");
    std::map<int, std::string> m;
    m[0] = "000";
    m[1] = "111";
    wxString& wxStrRef = wxStr;
    wxStrRef += L" Ref";
    std::string& stdStrRef = stdStr;
    stdStrRef += " Ref";

    std::list<std::string> l = {"a", "b", "c"};
    std::vector<std::string> v = {"a", "b", "c"};

    std::stack<std::string> s;
    s.push("a");
    s.push("b");

    wxArrayString arr;
    arr.Add(_T("arr1"));
    arr.Add(_T("arr2"));
    arr.Add(_T("arr3"));
    arr.Add(_T("arr4"));


    return 0;
}
--- End code ---


If you set a breakpoint in the first line "int x", then, you have "info local" enabled in your debugger setting dialog. You will get the gdb crashed, or python will generate many Errors.

that's because, at this moment, all the local variables were not initialized. I'm not sure how to solve this kind of problem, is it related to GCC? GDB? or only python script?

Here is a discussion on gdb:

http://sourceware.org/bugzilla/show_bug.cgi?id=11407


 

oBFusCATed:
As it seems there are some problems in the pretty printers in GDB and GCC as far as I know doesn't emit debug info for the status of the variable (initialized/non initialized).

So there are problems in both programs :(

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