Re: [Help-smalltalk] Add shortcuts to the visualgst/debugger

[Gwenaël Casaccio]

On 03/10/2013 18:40, Paolo Bonzini wrote:
> Il 30/09/2013 11:33, Holger Hans Peter Freyther ha scritto:
> > On Mon, Sep 30, 2013 at 10:47:31AM +0200, Holger Hans Peter Freyther wrote:
> >
> > Hi,
> >
> > and one more information:
> >
> > > So I think what is happening is the following:
> > >
> > > * We are in the glib mainloop
> > > * We get an event (F7.. keyboard)
> > > * We use gst_nvmsg_send which will create a new Process (call-in)
> > > * We dispatch GtkDebugger>>#stepOver
> > > * We want to step/resume another process..
> > > * We wait on a semaphore..
> > > * The debugged process doesn't run (for whatever reason)
> > > * The call-in is waiting on a Semaphore as well
> > to make it worse.. the call-in will be suspended because it is
> > launching a debugger...
> >
> > 'Invalid index 13: index out of range'
> > SystemExceptions.IndexOutOfRange(Exception)>>signal (ExcHandling.st:254)
> > SystemExceptions.IndexOutOfRange class>>signalOn:withIndex: (SysExcept.st:665)
> > String(Object)>>checkIndexableBounds: (Object.st:798)
> > String>>at: (String.st:312)
> > String(SequenceableCollection)>>replaceFrom:to:with:startingAt: 
> > (SeqCollect.st:554)
> > String>>replaceFrom:to:with:startingAt: (String.st:296)
> > String(ArrayedCollection)>>copyFrom:to: (ArrayColl.st:236)
> > ReadStream(PositionableStream)>>copyFrom:to: (PosStream.st:156)
> > STInST.RBParser>>errorLine (Parser.star#VFS.ZipFile/RBParser.st:183)
> > STInST.RBParser>>parserError: (Parser.star#VFS.ZipFile/RBParser.st:207)
> > STInST.RBParser>>parseExpression (Parser.star#VFS.ZipFile/RBParser.st:153)
> > STInST.RBParser class>>parseExpression:onError: 
> > (Parser.star#VFS.ZipFile/RBParser.st:35)
> > STInST.RBParser class>>parseExpression: (Parser.star#VFS.ZipFile/RBParser.st:26)
> > UndefinedObject>>executeStatements (a String:1)
> >        6         ^self activateHandler: (onDoBlock isNil and: [ self 
> > isResumable ])
> >
> > The question is.. is this a VisualGST issue or should the VM
> > be more robust against such deadlocks? I think we could have
> > a couple of
> >
> > if (cur_state == STATE_DISPATCHING && blocking)
> >      {
> >        event_loop_unlock ();
> >        return;
> >      }
> >
> > in the vm, like in gst_interpret?
> >
> > comments?
> After some debugging with Holger, I think the problem is that VisualGST
> is not handling the DebuggerReentered exception.
>
> All invocations of #step, #finish: etc. should be wrapped with a
> DebuggerReentered exception handler.  You can look at how MiniDebugger
> does it.  MiniDebugger (and the Blox debugger too) creates a new
> command-loop, but perhaps VisualGST can just change the window title or
> something like that.
>
> Paolo

I've tried and it failed again but if I fork the debugger command

[ debugger next.
  self updateContext ] fork

and it grabs the exception without any problem

Gwen