RE: Reverse debugging

Marc Khouzam
2009-07-21T03:21:50Z

> -----Original Message-----
> From: Hui Zhu [mailto:teawater@gmail.com]
> Sent: July-20-09 10:51 AM
> To: Marc Khouzam
> Cc: Nick Roberts; Daniel Jacobowitz; gdb@sources.redhat.com;
> Michael Snyder
> Subject: Re: Reverse debugging
>
> Hi Marc,
>
> About change nquery to yquery, if the user answer y, a lot of record
> entry will be delete. So I think nquery to be default is better.
>
> Your patch change yquery to query is OK with me.
>
> In prec, I use a lot of yquery and nquery and looks like mi cannot
> control query very well. So I think add some switches to let you can
> control prec more better.
>
> On the other hand, shell we do some work to make mi support
> query better?

I've just posted an RFC to try to get queries to work better
with frontends. I'm hoping you won't have to change PRecord.
Please see

http://sourceware.org/ml/gdb/2009-07/msg00150.html

Thanks

Marc

>
> Thanks,
> Hui
>
> On Mon, Jul 20, 2009 at 21:19, Marc
> Khouzam<marc.khouzam@ericsson.com> wrote:
> > Typo in my previous email.  Sorry.
> >
> >> (Note that I'm only suggesting to not make the query
> default to 'Y'.
> >> There would still be a query though.)
> >
> > Should have read (no "not")
> >
> >> (Note that I'm only suggesting to make the query default to 'Y'.
> >> There would still be a query though.)
> >
> >> -----Original Message-----
> >> From: gdb-owner@sourceware.org
> >> [mailto:gdb-owner@sourceware.org] On Behalf Of Marc Khouzam
> >> Sent: Monday, July 20, 2009 8:50 AM
> >> To: Hui Zhu; Nick Roberts
> >> Cc: Daniel Jacobowitz; gdb@sources.redhat.com; Michael Snyder
> >> Subject: RE: Reverse debugging
> >>
> >>
> >>
> >> > -----Original Message-----
> >> > From: Hui Zhu [mailto:teawater@gmail.com]
> >> > Sent: Sunday, July 19, 2009 11:27 PM
> >> > To: Marc Khouzam; Nick Roberts
> >> > Cc: Daniel Jacobowitz; gdb@sources.redhat.com; Michael Snyder
> >> > Subject: Re: Reverse debugging
> >> >
> >> > Thanks Marc,  but what about I keep it but add some
> switches for it?
> >> > I want keep the query to tui user.
> >> > For example:
> >> > set record query off
> >> > set record changememeory on
> >>
> >> (Note that I'm only suggesting to make the query default to 'Y'.
> >> There would still be a query though.)
> >>
> >> I've been giving the whole problem a little more thought, and I now
> >> think that it is the way queries are answered that should
> be changed
> >> generically.
> >>
> >> I'll post a patch today and see what people think.
> >>
> >> Note that the suggestion I will post will rely on 'set
> confirm off'.
> >> If Nick cannot use that then he'll still need you to have
> a switch to
> >> turn these queries off.
> >>
> >> Thanks
> >>
> >> Marc
> >>
> >>
> >> >
> >> > Thanks,
> >> > Hui
> >> >
> >> >
> >> > On Sun, Jul 19, 2009 at 11:19, Marc
> >> > Khouzam<marc.khouzam@ericsson.com> wrote:
> >> > >> -----Original Message-----
> >> > >> From: Daniel Jacobowitz [mailto:drow@false.org]
> >> > >> Sent: July-17-09 10:25 AM
> >> > >> To: Marc Khouzam
> >> > >> Cc: Nick Roberts; Hui Zhu; gdb@sources.redhat.com;
> Michael Snyder
> >> > >> Subject: Re: Reverse debugging
> >> > >>
> >> > >> On Fri, Jul 17, 2009 at 10:12:00AM -0400, Marc Khouzam wrote:
> >> > >> > I noticed that the previous CDT GDB integration has
> its console
> >> > >> > considered
> >> > >> > a tty.  It may be worth looking into the difference... when
> >> > >> time allows
> >> > >> > it :-)
> >> > >>
> >> > >> Wasn't someone just talking on cdt-dev about trouble with
> >> > whether DSF
> >> > >> used Spawner or not?  That'd do it.
> >> > >
> >> > > I was wrong about the console being a tty.  The old CDT GDB
> >> > integration
> >> > > console is also not a tty.  What they do though is use
> >> > > 'set confirm off'.  That makes sense since queries are
> >> > being answered
> >> > > automatically anyway.
> >> > >
> >> > > Nick, in your specific case 'confirm off' would work.
> The default
> >> > > answer to
> >> > > 'record stop' is yes (well, there is not default, but in
> >> > that case, 'y'
> >> > > is
> >> > > chosen).  If you don't want to always 'set confirm off' you
> >> > may consider
> >> > > setting it right before sending 'record stop' and turn
> it back on
> >> > > right after.  That may be a good enough workaround until
> >> there is a
> >> > > proper
> >> > > solution to this query problem.
> >> > >
> >> > > For me the problem for PRecord remains because the
> >> default value is
> >> > > not always what I want.  For example, in PRecord the
> >> default answer
> >> > > to changing memory and loosing the recorded history
> >> > > is "N", but as a frontend, I want to answer "Y".
> >> > >
> >> > > To fix this problem I suggest that in record.c,
> >> > > we replace 'nquery' with 'query'; that will make the
> >> > default be 'Y' when
> >> > >
> >> > > confirm is off or when there is no tty.  Note that this
> >> > seems to be what
> >> > >
> >> > > is being done everywhere else in GDB.  There is only one
> >> > case (pending
> >> > > breakpoints) that uses default queries, outside of PRecord.
> >> >  Except for
> >> > > that
> >> > > one case, it is really only PRecord that uses yquery and
> >> > nquery.  And
> >> > > the
> >> > > pending breakpoint case is not a problem for frontends
> that use MI
> >> > > because
> >> > > the MI command does not trigger the query.
> >> > >
> >> > > Note that up to now, I've been recompiling GDB with that
> >> suggestion
> >> > > so that I can properly use PRecord in Eclipse.
> >> > >
> >> > > The below patch implements the suggestion.
> >> > >
> >> > > Thanks
> >> > >
> >> > > Marc
> >> > >
> >> > > ChangeLog
> >> > > 2009-07-18  Marc Khouzam  <marc.khouzam@ericsson.com>
> >> > >
> >> > >        * record.c (record_store_registers): Replace nquery with
> >> > >        query to allow frontends to automatically answer 'y'.
> >> > >        (record_xfer_partial): Ditto.
> >> > >
> >> > >
> >> > > ### Eclipse Workspace Patch 1.0
> >> > > #P src
> >> > > Index: gdb/record.c
> >> > >
> >> ===================================================================
> >> > > RCS file: /cvs/src/src/gdb/record.c,v
> >> > > retrieving revision 1.8
> >> > > diff -u -r1.8 record.c
> >> > > --- gdb/record.c        2 Jul 2009 17:21:06 -0000       1.8
> >> > > +++ gdb/record.c        19 Jul 2009 03:06:01 -0000
> >> > > @@ -937,13 +937,13 @@
> >> > >          /* Let user choose if he wants to write register
> >> > or not.  */
> >> > >          if (regno < 0)
> >> > >            n =
> >> > > -             nquery (_("Because GDB is in replay mode,
> >> > changing the "
> >> > > +             query (_("Because GDB is in replay mode,
> >> > changing the "
> >> > >                        "value of a register will make the
> >> > execution "
> >> > >                        "log unusable from this point onward.  "
> >> > >                        "Change all registers?"));
> >> > >          else
> >> > >            n =
> >> > > -             nquery (_("Because GDB is in replay mode,
> >> changing the
> >> > > value "
> >> > > +             query (_("Because GDB is in replay mode,
> >> changing the
> >> > > value "
> >> > >                        "of a register will make the
> execution log
> >> > > unusable "
> >> > >                        "from this point onward.  Change
> >> > register %s?"),
> >> > >                      gdbarch_register_name (get_regcache_arch
> >> > > (regcache),
> >> > > @@ -993,7 +993,7 @@
> >> > >       if (RECORD_IS_REPLAY)
> >> > >        {
> >> > >          /* Let user choose if he wants to write memory
> >> or not.  */
> >> > > -         if (!nquery (_("Because GDB is in replay mode,
> >> writing to
> >> > > memory "
> >> > > +         if (!query (_("Because GDB is in replay
> mode, writing to
> >> > > memory "
> >> > >                         "will make the execution log
> >> > unusable from this
> >> > > "
> >> > >                         "point onward.  Write memory at
> >> > address %s?"),
> >> > >                       paddress (target_gdbarch, offset)))
> >> > >
> >> > >
> >> > >
> >> > >
> >> >
> >>
> >
>