Re: How to write native (i.e. C/C++) plugin for gdb?

[Doug Evans <dje@google.com>]

On Wed, Dec 25, 2013 at 8:51 AM, Dmitry Samersoff <dms@samersoff.net> wrote:
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> Everyone,
>
> Just found a year old discussion about Abhijit proposal.
>
> So answering to upcoming question - why not a Python.
>
> Python is very good staff if your speak about source level debugging.
> If you have to debug optimized binary python doesn't help match for
> two reason -
>
>   1) you have to port all native data structure you plan to work with
>  to python.

Hi.

This typically isn't that hard an exercise, have you looked into it?

>   2) python performance is not always acceptable and you not always
> ever able to run a python.

I'd like to see the data that shows the performance isn't acceptable.
This could just be mistaken impressions.

> To get a better picture of native plugins in action, please, take a
> look at solaris mdb.
>
> - -Dmitry
>
> On 2013-12-25 19:32, Dmitry Samersoff wrote:
>> Joel,
>>
>> Thank you for the response.
>>
>> I found this patch
>> https://sourceware.org/ml/gdb-patches/2012-05/msg00500.html - many
>> thanks to Abhijit.
>>
>> 1. What is the reason to keep it off main trunk? Is there a chance
>> to have it changed?
>>
>> 2. What API is available from within a plugin? i.e. how I can
>> access coredump memory?
>>
>> -Dmitry
>>
>> On 2013-12-24 18:47, Joel Brobecker wrote:
>>>> I need to implement scenario like one below:
>>>>
>>>> (gdb) load-plugin  libgdbjvm.so (gdb) attach PID (gdb) jvm
>>>> show loaded-classes (gdb) jvm show java-threads (gdb) jvm show
>>>> code-cache
>>
>>> Maybe you could add some routines in your program that are solely
>>>  intended for debugging purposes, and then define commands that
>>> call those routines. Off hand, that's the only way I can think
>>> of. Otherwise, interface the C++ stuff you need from Python - if
>>> necessary, export some stuff to C?
>>
>>
>>
>>
>
> - --
> Dmitry Samersoff
> Saint Petersburg, Russia, http://devnull.samersoff.net
> * There will come soft rains  ...
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