[ruby-fltk-devel] Fl::paste dependant on Fl::run?

[Kent D. <ke...@st...>]

Hi.

As I'm trying to implement the "Simple Text Editor" sample in Ruby-Fltk,
(or should that be Ruby-FLTK now? ;-) I found out that the Fl::paste
wasn't wrapped.

So I gave it a naive try, which works, but seg-faults if Fltk.paste(
widget ) is called outside when Fltk.run is running...

I'm guessing that this is due to something in FLTK, and I wonder if
there is any to check to see that the Fltk.run is running? (See below
about Fl::check and Fl::ready)

<CVSDIFF>
[kentda@v128a ruby-fltk]$ cvs diff
? test/fl_func.rb
cvs server: Diffing .
Index: fltk.cc
===================================================================
RCS file: /cvsroot/ruby-fltk/ruby-fltk/fltk.cc,v
retrieving revision 1.65
diff -r1.65 fltk.cc
849a850,865
> /**
>  * the Fl::paste(Fl_Widget*) method
>  */
> static VALUE rb_fltk_paste( VALUE self, VALUE widget ){
>   Fl_Widget *reciever = NULL;
>   reciever =  rb_to_fl(widget);
>   if(reciever) {
>     Fl::paste( *reciever );
>   }else{
>     rb_raise(rb_eArgError, "Need widget to send paste-event to.");
>   }    
>   return Qnil;
> }
> 
> 
> 
972a989
>   DEF_MODULE_FUNC(paste,1);
</CVSDIFF>


Some testcode
<CODE>
require 'rubyfltk.so'
w = Fltk::Window.new(0,0,200,200)
b = Fltk::Button.new(0,0,20,20,"X"){|a,b|
  Fltk.paste(w)
}
w.show
#Fltk.paste( b) # this crashes
Fltk.run # here, pushing the button which calls Fltk.paste(w) goes ok.
#Fltk.paste( b ) # this crashes too.
</CODE>


After writing the above, I did try using Fl::check(), but I'm not sure
that is a safe bet, since the Fl::ready() documentation talks about
callbacks maybe being illegal, and Fl::ready() returns values that don't
seem to mean quite the same.

The seg-faults disappear if I add this test to the rb_fltk_paste
implementation before Fl::paste...
<CODE>
  if(!Fl::check())
    rb_raise(rb_eSystemCallError, "FLTK does not appear to be taking
events!");
</CODE>

I hope my code isn't totally embarrasing :-)

-- 
<[ Kent Dahl ]>================<[ http://www.stud.ntnu.no/~kentda/ ]>
  )____(stud.techn.;ind.øk.data)||(softwareDeveloper.at(Trustix))_( 
 /"Opinions expressed are mine and not those of my Employer,      "\
( "the University, my girlfriend, stray cats, banana fruitflies,  " )
 \"nor the frontal lobe of my left cerebral hemisphere.           "/