Catching Ctrl-C SIGINT

[Christopher Broeg <broeg@astro.uni-jena.de~>]

Hi,

I am having some trouble with protected types. I am trying to do some 
cleanup work if the user presses Ctrl-C SIGINT.
For this I wrote a little test program. The problem is getting the 
information about the raised interrupt back to the main program. I tried 
using a little task that calls a entry in a protected type:

with Catch_Interrupt;

with Ada.Text_IO;use Ada.Text_IO;
procedure Test1 is
    Stop: exception;

    task Get_Info is
       entry Stop;
    end Get_info;
    task body Get_Info is
    begin
       loop
          Catch_Interrupt.Event.wait;
	 -- here comes the code that handles the interrupt received
          select
             accept Stop do
                Stop;
             end Stop;
          or
             terminate;
          end select;
       end loop;
    end Get_Info;


begin

    for i in 1 .. 5 loop
       Put(Integer'Image(i));
       delay 1.0;
    end loop;

end Test1;


the package actually doing the interrupt catching is:

with Ada.Interrupts;
with Ada.Interrupts.names;
package Catch_Interrupt is

    Sig_Int_Caught : exception;

    procedure Signal_Public;

    protected Catch_Interrupt is
       procedure Clean_up;
       pragma Unreserve_All_Interrupts;
       --pragma interrupt_Handler(Clean_Up);
       pragma Attach_Handler(Clean_Up,Ada.Interrupts.Names.SIGINT);
    end Catch_Interrupt;

    protected Event is
       entry Wait;
       procedure Signal;
    private
       Allowed : Boolean := False;
    end Event;
end Catch_Interrupt;


with Ada.Text_IO;
use Ada.Text_IO;
package body Catch_Interrupt is

    procedure Signal_Public is
    begin
       Event.Signal;
    end Signal_Public;


    protected body Catch_Interrupt is
       procedure Clean_up is
       begin
          Put_line("Interrupt SIGINT caught. sending signal ");
          Signal_public;
          Put_line("SIGNAL SENT. ");
       end Clean_Up;
    end Catch_Interrupt;

    protected body Event is
       entry Wait when allowed is
       begin
          Put_line("catch_interrupt msg: in entry wait");
       end Wait;
       procedure  Signal is
       begin
          Put_line("Signal received!!!");
          Allowed := True;
       end Signal;
    end Event;
end Catch_Interrupt;

Here the problem:
I do get the message
"Interrupt SIGINT caught. sending signal "
but the signal_public procedure never manages to send the signal. I 
don't know why. If I call the signal_public procedure from test1 it 
works, but is of course useless.

Can you give me any hints on what I am doing wrong? I am lost.

Maybe there is a better way to react upon the interrupt? But still I am 
wondering why my solution is not working.

Thanx a lot,

Chris