User forums > Using Code::Blocks

Debugging QString

(1/7) > >>

LordCB:
Hello friends,

during programming with Qt in CB I watch QStrings in this manner during debugging


--- Code: ---QString qTest = qstrLine;
std::string strTest = qTest.toStdString();

--- End code ---

Is there a more convinient way to do this. Is there a direct watch method.
I don´t like to insert code to watch some variables during debugging and it is more to do;

oBFusCATed:
You could add a debugger script to parse the QStrings.
For more info see here: http://wiki.codeblocks.org/index.php?title=Debugger_scripts

LordCB:
Ok, ...

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

// QString
    driver.RegisterType(
        _T("Qt String"),
        _T("[^[:alnum:]_]*QString[^[:alnum:]_]*"),
        _T("Evaluate_QString"),
        _T("Parse_QString")
    );

    Log(_T("RegisterTypes is being called"));
}
function Evaluate_QString(type, a_str, start, count)
{
//what to do???
    return a_str;
}


function Parse_QString(a_str, start)
{
//what to do???
    return a_str;
}

--- End code ---

Hmm and now any suggestions...

where comes my qstring variable in. The a_str seems to be a std::string.

oBFusCATed:

--- Code: ---function Evaluate_QString(type, a_str, start, count)

--- End code ---

a_str is the string you have written in the watch windows (my_string, str, my_struct.name, etc).
In this function you are supposed to generate a command that gdb can execute and produce some output you can parse in the
Parse_QString function.


--- Code: ---function Parse_QString(a_str, start)

--- End code ---
Here a_str is the result of the gdb command, just executed.

For example if you have  'QString s = "test"', you want to execute something like "output s.m_pinternal_string" and if the result is "test" in the parse function you return the a_str directly because it doesn't need any parsing and conversion.
Look for file gdb_types.script, there you can see implementations for some types: std::string, wxstring and std::vector

eranif:
This is how I debug QString:

I add the following user function to the debugger on the startup:

--- Code: ---define printqstring
    printf "(QString)0x%x (length=%i): \"",&$arg0,$arg0.d->size
    set $i=0
    while $i < $arg0.d->size
        set $c=$arg0.d->data[$i++]
        if $c < 32 || $c > 127
                printf "\\u0x%04x", $c
        else
                printf "%c", (char)$c
        end
    end
    printf "\"\n"
end
--- End code ---
Next, to view QString, I simply type:

--- Code: ---printqstring <variable_name>
--- End code ---

I guess that CodeBlocks can automate this procedure for you (i.e. register the user function when debugging session starts and to choose the command 'printqstring' over 'print' when a tooltip is requested)

Eran

Navigation

[0] Message Index

[#] Next page