From c1aba9a84001fc94ccb64aa82c82ec446a27fa7c Mon Sep 17 00:00:00 2001
From: Vitor Santos Costa <vsc@dcc.fc.up.pt>
Date: Wed, 22 Apr 2009 16:13:08 -0500
Subject: [PATCH] fix the signal handling a bit better.

---
 pl/boot.yap  |  3 ++-
 pl/debug.yap | 34 +++++++++++++++++-----------------
 2 files changed, 19 insertions(+), 18 deletions(-)

diff --git a/pl/boot.yap b/pl/boot.yap
index dda517ff5..5e2135792 100644
--- a/pl/boot.yap
+++ b/pl/boot.yap
@@ -1160,7 +1160,8 @@ throw(Ball) :-
 'catch_ball'(Ball, V) :-
 	var(V),
 	nonvar(Ball),
-	functor(Ball, Name, _),
+	Ball = error(Type,_), % internal error ??
+	functor(Type, Name, _),
 	atom_codes(Name, [0'$|_]), %'0
 	!, fail.
 'catch_ball'(C, C).
diff --git a/pl/debug.yap b/pl/debug.yap
index 309a76d47..d6c2c8d37 100644
--- a/pl/debug.yap
+++ b/pl/debug.yap
@@ -340,33 +340,33 @@ debugging :-
 '$loop_spy'(GoalNumber, G, Module, CalledFromDebugger) :-
 	yap_hacks:current_choice_point(CP),
 	'$system_catch'('$loop_spy2'(GoalNumber, G, Module, CalledFromDebugger, CP),
-		    Module, '$debug_event'(Event),
-		    '$loop_spy_event'(Event, GoalNumber, G, Module, CalledFromDebugger)).
+		    Module, error(Event,Context),
+		    '$loop_spy_event'(error(Event,Context), GoalNumber, G, Module, CalledFromDebugger)).
 
 % handle weird things happening in the debugger.		    
-'$loop_spy_event'('$retry_spy'(G0), GoalNumber, G, Module, CalledFromDebugger) :-
+'$loop_spy_event'(error('$retry_spy'(G0),_), GoalNumber, G, Module, CalledFromDebugger) :-
      G0 >= GoalNumber, !,
      '$loop_spy'(GoalNumber, G, Module, CalledFromDebugger).
-'$loop_spy_event'('$retry_spy'(GoalNumber), _, _, _, _) :- !,
-     throw('$debug_event'('$retry_spy'(GoalNumber))).
-'$loop_spy_event'('$fail_spy'(G0), GoalNumber, G, Module, CalledFromDebugger) :-
+'$loop_spy_event'(error('$retry_spy'(GoalNumber),_), _, _, _, _) :- !,
+     throw(error('$retry_spy'(GoalNumber),[])).
+'$loop_spy_event'(error('$fail_spy'(G0),_), GoalNumber, G, Module, CalledFromDebugger) :-
      G0 >= GoalNumber, !,
     '$loop_fail'(GoalNumber, G, Module, CalledFromDebugger).
-'$loop_spy_event'('$fail_spy'(GoalNumber), _, _, _, _) :- !,
-     throw('$debug_event'('$fail_spy'(GoalNumber))).
-'$loop_spy_event'('$done_spy'(G0,G), GoalNumber, G, _, CalledFromDebugger) :-
+'$loop_spy_event'(error('$fail_spy'(GoalNumber),_), _, _, _, _) :- !,
+     throw(error('$fail_spy'(GoalNumber),[])).
+'$loop_spy_event'(error('$done_spy'(G0),_), GoalNumber, G, _, CalledFromDebugger) :-
      G0 >= GoalNumber, !,
      '$continue_debugging'(CalledFromDebugger).
-'$loop_spy_event'('$done_spy'(GoalNumber), _, _, _, _) :- !,
-     throw('$debug_event'('$done_spy'(GoalNumber))).
-'$loop_spy_event'(abort, _, _, _, _) :- !,
-     throw('$abort').
+'$loop_spy_event'(error('$done_spy'(GoalNumber),_), _, _, _, _) :- !,
+     throw(error('$done_spy'(GoalNumber),[])).
 '$loop_spy_event'(Event, GoalNumber, G, Module, CalledFromDebugger) :-
      '$debug_error'(Event),     
      '$system_catch'(
 		     ('$trace'(exception,G,Module,GoalNumber,_),fail),
-		     Module,'$debug_event'(NewEvent),
-		     '$loop_spy_event'(NewEvent, GoalNumber, G, Module, CalledFromDebugger)).
+		     Module,
+		     error(NewEvent,NewContext),
+		     '$loop_spy_event'(error(NewEvent,NewContext), GoalNumber, G, Module, CalledFromDebugger)
+		    ).
 
 
 '$debug_error'(Event) :-
@@ -603,7 +603,7 @@ debugging :-
 	halt.
 '$action'(0'f,_,CallId,_,_,_) :- !,		% 'f		fail
 	'$scan_number'(0'f, CallId, GoalId),    %'f
-	throw('$debug_event'('$fail_spy'(GoalId))).
+	throw(error('$fail_spy'(GoalId),[])).
 '$action'(0'h,_,_,_,_,_) :- !,			% 'h		help
 	'$action_help',
 	'$skipeol'(104),
@@ -653,7 +653,7 @@ debugging :-
 '$action'(0'r,_,CallId,_,_,_) :- !,		        % 'r		retry
         '$scan_number'(0'r,CallId,ScanNumber),		% '
         '$debug_on'(true),
-	throw('$debug_event'('$retry_spy'(ScanNumber))).
+	throw(error('$retry_spy'(ScanNumber),[])).
 '$action'(0's,P,CallNumber,_,_,on) :- !,		% 's		skip
 	'$skipeol'(0's),				% '		
 	( (P=call; P=redo) ->