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A way to see wxString of wxWidgets 2.9.2 with gdb ?

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ollydbg:
I have just take several hours to build a wx 2.9.2 under pcx's mingw 4.6.1 then try to see whether it works on wxWidgets.
it seems that you need to change the file:
MinGW_gcc4.6.1release_static_win32\bin\libwx\v28\printers.py

Then use the content below for the wxString class:

--- Code: ---# shamelessly stolen from std::string example
@register_pretty_printer
class wxStringPrinter:
   
    regex = re.compile('^wxString$$');
    @static
    def supports(typename):
        return wxStringPrinter.regex.search(typename)
    @static
    def is_undefine(val):
        try:
            val['m_impl']['_M_dataplus']['_M_p'].string()
            return True
        except:
            return False

    def __init__(self, val):
        self.val = val

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

    def display_hint(self):
        return 'string'

--- End code ---

then, everything works fine.

here is my test debug log:


--- Quote ---> p msg
$1 = "wxWidgets 2.9.2-Windows-Unicode build"
>>>>>>cb_gdb:
--- End quote ---

my test code was just use wx wizard to generate a simple wx smith project.

BTW: I use you command to build the wx library. such as:


--- Code: ---echo Add MinGW path
set PATH=D:\code\MinGW_gcc4.6.1release_static_win32\bin;%PATH%
cd wxWidgets-2.9.2\build\msw
mingw32-make -f makefile.gcc MONOLITHIC=1 SHARED=1 UNICODE=1 BUILD=release USE_XRC=1 DEBUG_FLAG=0

--- End code ---

But I found that I need to manuall change the setup.h, and un-comment the line: (line 70)

--- Code: ---  #define wxDEBUG_LEVEL 0
--- End code ---

otherwise, I will have a build error, something like:

--- Code: ---undefined reference to `wxTheAssertHandler'
--- End code ---

more details can be found:
http://trac.wxwidgets.org/ticket/12626

So, I guess the option :DEBUG_FLAG=0 should not be used. :D

theojk:
Hi,

for all those, who dont want to use python:

I have modified the small script from CodeBlocks (10.5) for displaying wxStrings.
The old code located in <path to C::B>/share/CodeBlocks/scripts/gdb_types.script

--- Code: ---function Evaluate_wxString(type, a_str, start, count)
{
    local oper = _T(".");

    if (type.Find(_T("*"), false) > 0)
        oper = _T("->");

    local result = _T("output /c ") + a_str + oper + _T("m_pchData[") + start + _T("]@");
    if (count != 0)
        result = result + count;
    else
        result = result + _T("((wxStringData*)") + a_str + oper + _T("m_pchData - 1)->nDataLength");
    return result;
}
--- End code ---
doesnt work on wxWidgets 2.9.2 anymore
this code

--- Code: ---function Evaluate_wxString(type, a_str, start, count)
{
    local oper = _T(".");

    if (type.Find(_T("*"), false) > 0)
        oper = _T("->");

    local result = _T("output /c *((wxChar *)(") + a_str + oper + _T("fn_str()))@") + a_str + oper + _T("Length()");

    return result;
}
--- End code ---
displays the String again.

Hope this helps a little bit.

P.S. dont overwrite the whole file, but only the function Evaluate_wxString.  :wink:

Manolo:
Hi
Starting with wx 2.9, the wxString internal representation depends on the OS. See
http://docs.wxwidgets.org/trunk/overview_string.html

To get your own OS suitable type, use wxString::wx_str(), which returns a pointer of the needed type.
To get the length (in characters, not chars, no bytes, no etc.) there are three functions: Len(), Length() and length().
If you use Len(), then the compiler knows about it and can use it too. If your code does not, GDB neither.

In Squirrel language, I can't find a way for telling the size of an "external" array. So let's GDB manage it.
Because wxString is moving to use std::string, it seems length() (lower case letter) is available.

With all of this, the Evaluate_wxString function at gdb_types.script would look like:


--- Code: ---function Evaluate_wxString(type, a_str, start, count)
{
    local oper = _T(".");

    if (type.Find(_T("*"), false) > 0)
        oper = _T("->");

    local result = _T("output /c ") + a_str + oper + _T("wx_str()") + _T("[") + start + _T("]@");
    if (count != 0)
        result = result + count;
    else
        result = result + a_str + oper + _T("length()");
    return result;
}

--- End code ---

Now, the C:B Watches window shows the contents of the wxString type var.
Note the GDB command 'output /c' will treat each character as an integer and display it in 7 bit ASCII or escaped sequences if value>127
So, if your wxString has some characters not representable in 7 bit ASCII, you'll see escaped sequences for them.

N.B.
Looking at wx2.8.12 wxWidgets string.h, I find both functions (wx_str & length) are defined. So this script should work also for [all?] wx 2.8 series.

Regards
Manolo

theojk:
Its working.  :D 
And so it might be the better way, working on other platforms too.  :wink:

Thank You.

Feneck91:
It's seems that it doesn't work in wxWidgets 2.9.4 in unicode. Another way ?

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