Rewrite constraint handling

The internal representation for constraints (and object sets)
as produced by the parser was awkward, making further processing
convoluted. Here follows some examples of the old representation
for INTEGER constraints.

The constraint 1..2 is represented as:

  {'ValueRange',{1,2}}

If we extend the constraint like this:

  1..2, ...,

or like this:

  1..2, ..., 3

the representation would be:

  {{'ValueRange',{1,2}},[]}

and

  {{'ValueRange',{1,2}},{'SingleValue',3}}

respectively. Note that the pattern {A,B} will match all these
constraints.

When combining constraints using set operators:

  1..2 | 3..4 ^ 5..6

the representation will no longer be a tuple but a list:

  [{'ValueRange',{1..2}} union
   {'ValueRange',{3..4}} intersection
   {'ValueRange',{5..6}}]

The parse has full knowledge of the operator precedence; unfortunately,
the following pass (asn1ct_check) must also have the same knowledge
in order to correctly evaluate the constraints.

If we would change the order of the evaulation with round brackets:

  (1..2 | 3..4) ^ 5..6

there would be a nested listed in the representation:

  [[{'ValueRange',{1..2}} union {'ValueRange',{3..4}}]
   intersection {'ValueRange',{5..6}}]

We will change the representation to make it more explicit.
At the outer level, a constraint is always represented as

  {element_set,Root,Extension}

Extension will be 'none' if there is no extension, and 'empty' if
there is an empty extension. Root may also be 'empty' in an object set
if there are no objects in the root. Thus the constraints:

  1..2
  1..2, ...
  1..2, ..., 3

will be represented as:

  {element_set,{'ValueRange',{1,2}},none}
  {element_set,{'ValueRange',{1,2}},empty}
  {element_set,{'ValueRange',{1,2}},{'SingleValue',3}}

We will change the set operators too. This constraint:

  1..2 | 3..4 ^ 5..6

will be represented as:

  {element_set,
      {union,
        {'ValueRange',{1,2}},
        {intersection,
           {'ValueRange',{3,4}},
           {'ValueRange',{5,6}}},
       none}}

which is trivial to understand and evaluate. Similarly:

  (1..2 | 3..4) ^ 5..6

will be represented as:

  {element_set,
      {intersection,
        {union,{'ValueRange',{1,2}},{'ValueRange',{3,4}}},
        {'ValueRange',{5,6}}},
      none}

1 files changed, 32 insertions, 134 deletions

diff --git a/lib/asn1/src/asn1ct_parser2.erl b/lib/asn1/src/asn1ct_parser2.erl
index 9b2fc0b046..c19811ea49 100644
--- a/lib/asn1/src/asn1ct_parser2.erl
+++ b/lib/asn1/src/asn1ct_parser2.erl
@@ -655,7 +655,8 @@ parse_TypeWithConstraint([{'SEQUENCE',_},Lpar = {'(',_}|Rest]) ->
 parse_TypeWithConstraint([{'SEQUENCE',_},{'SIZE',_},Lpar = {'(',_}|Rest]) ->
     {Constraint,Rest2} = parse_Constraint([Lpar|Rest]),
     #constraint{c=C} = Constraint,
-    Constraint2 = Constraint#constraint{c={'SizeConstraint',C}},
+    Constraint2 = Constraint#constraint{c={element_set,{'SizeConstraint',C},
+					   none}},
     Rest4 = case Rest2 of
 		[{'OF',_}, {identifier,_,_Id}|Rest3] ->
 %%% TODO: make some use of the identifier, maybe useful in the XML mapping
@@ -689,7 +690,8 @@ parse_TypeWithConstraint([{'SET',_},Lpar = {'(',_}|Rest]) ->
 parse_TypeWithConstraint([{'SET',_},{'SIZE',_},Lpar = {'(',_}|Rest]) ->
     {Constraint,Rest2} = parse_Constraint([Lpar|Rest]),
     #constraint{c=C} = Constraint,
-    Constraint2 = Constraint#constraint{c={'SizeConstraint',C}},
+    Constraint2 = Constraint#constraint{c={element_set,
+					   {'SizeConstraint',C},none}},
     Rest4 = case Rest2 of
 		[{'OF',_}, {identifier,_,_Id}|Rest3] ->
 %%% TODO: make some use of the identifier, maybe useful in the XML mapping
@@ -876,19 +878,16 @@ parse_TypeColonValue(Tokens) ->
 parse_SubtypeConstraint(Tokens) ->
     parse_ElementSetSpecs(Tokens).
 
-parse_ElementSetSpecs([{'...',_}|Rest]) ->
-    {Elements,Rest2} = parse_ElementSetSpec(Rest),
-    {{[],Elements},Rest2};
 parse_ElementSetSpecs(Tokens) ->
     {RootElems,Rest} = parse_ElementSetSpec(Tokens),
     case Rest of
 	[{',',_},{'...',_},{',',_}|Rest2] ->
 	    {AdditionalElems,Rest3} = parse_ElementSetSpec(Rest2),
-	    {{RootElems,AdditionalElems},Rest3};
+	    {{element_set,RootElems,AdditionalElems},Rest3};
 	[{',',_},{'...',_}|Rest2] ->
-	    {{RootElems,[]},Rest2};
+	    {{element_set,RootElems,empty},Rest2};
 	_ ->
-	    {RootElems,Rest}
+	    {{element_set,RootElems,none},Rest}
     end.
 
 parse_ElementSetSpec([{'ALL',_},{'EXCEPT',_}|Rest]) ->
@@ -909,14 +908,8 @@ parse_Unions(Tokens) ->
     case {InterSec,Unions} of
 	{InterSec,[]} ->
 	    {InterSec,Rest2};
-	{{'SingleValue',V1},{'SingleValue',V2}} ->
-	    {{'SingleValue',ordsets:union(to_set(V1),to_set(V2))},Rest2};
-	{V1,V2} when is_list(V2) ->
-	    {[V1] ++ [union|V2],Rest2};
 	{V1,V2} ->
-	    {[V1,union,V2],Rest2}
-%	Other ->
-%	    throw(Other)
+	    {{union,V1,V2},Rest2}
     end.
 
 parse_UnionsRec([{'|',_}|Rest]) ->
@@ -925,12 +918,8 @@ parse_UnionsRec([{'|',_}|Rest]) ->
     case {InterSec,URec} of
 	{V1,[]} ->
 	    {V1,Rest3};
-	{{'SingleValue',V1},{'SingleValue',V2}} ->
-	    {{'SingleValue',ordsets:union(to_set(V1),to_set(V2))},Rest3};
-	{V1,V2} when is_list(V2) ->
-	    {[V1] ++ [union|V2],Rest3};
 	{V1,V2} ->
-	    {[V1,union,V2],Rest3}
+	    {{union,V1,V2},Rest3}
 	end;
 parse_UnionsRec([{'UNION',Info}|Rest]) ->
     parse_UnionsRec([{'|',Info}|Rest]);
@@ -943,13 +932,8 @@ parse_Intersections(Tokens) ->
     case {InterSec,IRec} of
 	{V1,[]} ->
 	    {V1,Rest2};
-	{{'SingleValue',V1},{'SingleValue',V2}} ->
-	    {{'SingleValue',
-	      ordsets:intersection(to_set(V1),to_set(V2))},Rest2};
-	{V1,V2} when is_list(V2) ->
-	    {[V1] ++ [intersection|V2],Rest2};
 	{V1,V2} ->
-	    {[V1,intersection,V2],Rest2}
+	    {{intersection,V1,V2},Rest2}
     end.
 
 %% parse_IElemsRec(Tokens) -> Result
@@ -958,15 +942,10 @@ parse_IElemsRec([{'^',_}|Rest]) ->
     {InterSec,Rest2} = parse_IntersectionElements(Rest),
     {IRec,Rest3} = parse_IElemsRec(Rest2),
     case {InterSec,IRec} of
-	{{'SingleValue',V1},{'SingleValue',V2}} ->
-	    {{'SingleValue',
-	      ordsets:intersection(to_set(V1),to_set(V2))},Rest3};
 	{V1,[]} ->
-	    {V1,Rest3};
-	{V1,V2} when is_list(V2) ->
-	    {[V1] ++ [intersection|V2],Rest3};
+	    {V1,Rest2};
 	{V1,V2} ->
-	    {[V1,intersection,V2],Rest3}
+	    {{intersection,V1,V2},Rest3}
     end;
 parse_IElemsRec([{'INTERSECTION',Info}|Rest]) ->
     parse_IElemsRec([{'^',Info}|Rest]);
@@ -1589,14 +1568,11 @@ parse_ObjectSet(Tokens) ->
     throw({asn1_error,{get_line(hd(Tokens)),get(asn1_module),
 		       [got,get_token(hd(Tokens)),expected,'{']}}).
 
-parse_ObjectSetSpec([{'...',_}|Rest]) ->
-    case Rest of
-	[{',',_}|Rest2] ->
-	    {Elements,Rest3}=parse_ElementSetSpecs(Rest2),
-	    {{[],Elements},Rest3};
-	_ ->
-	    {['EXTENSIONMARK'],Rest}
-    end;
+parse_ObjectSetSpec([{'...',_},{',',_}|Tokens0]) ->
+    {Elements,Tokens} = parse_ElementSetSpec(Tokens0),
+    {{element_set,empty,Elements},Tokens};
+parse_ObjectSetSpec([{'...',_}|Tokens]) ->
+    {{element_set,empty,empty},Tokens};
 parse_ObjectSetSpec(Tokens) ->
     parse_ElementSetSpecs(Tokens).
 
@@ -1885,7 +1861,7 @@ parse_TableConstraint(Tokens) ->
 
 parse_SimpleTableConstraint(Tokens) ->
     {ObjectSet,Rest} = parse_ObjectSet(Tokens),
-    {{simpletable,ObjectSet},Rest}.
+    {{element_set,{simpletable,ObjectSet},none},Rest}.
 
 parse_ComponentRelationConstraint([{'{',_}|Rest]) ->
     {ObjectSet,Rest2} = parse_DefinedObjectSet(Rest),
@@ -1894,7 +1870,10 @@ parse_ComponentRelationConstraint([{'{',_}|Rest]) ->
 	    {AtNot,Rest4} = parse_AtNotationList(Rest3,[]),
 	    case Rest4 of
 		[{'}',_}|Rest5] ->
-		    {{componentrelation,ObjectSet,AtNot},Rest5};
+		    Ret = {element_set,
+			   {componentrelation,ObjectSet,AtNot},
+			   none},
+		    {Ret,Rest5};
 		[H|_T]  ->
 		    throw({asn1_error,{get_line(H),get(asn1_module),
 				       [got,get_token(H),expected,'}']}})
@@ -2333,12 +2312,6 @@ check_rest([]) ->
 check_rest(_) ->
     false.
 
-
-to_set(V) when is_list(V) ->
-	ordsets:from_list(V);
-to_set(V) ->
-	ordsets:from_list([V]).
-
 parse_AlternativeTypeLists(Tokens) ->
     parse_AlternativeTypeLists(Tokens,[]).
 
@@ -3062,95 +3035,20 @@ parse_PresenceConstraint(Tokens) ->
     {asn1_empty,Tokens}.
 
 
-% merge_constraints({Rlist,ExtList}) -> % extensionmarker in constraint
-%     {merge_constraints(Rlist,[],[]),
-%      merge_constraints(ExtList,[],[])};
-
-%% An arg with a constraint with extension marker will look like
-%% [#constraint{c={Root,Ext}}|Rest]
-	
 merge_constraints(Clist) ->
     merge_constraints(Clist, [], []).
 
-merge_constraints([Ch|Ct],Cacc, Eacc) ->
-    NewEacc = case Ch#constraint.e of
-		  undefined -> Eacc;
-		  E -> [E|Eacc]
-	      end,
-    merge_constraints(Ct,[fixup_constraint(Ch#constraint.c)|Cacc],NewEacc);
-
-merge_constraints([],Cacc,[]) ->
-%%    lists:flatten(Cacc);
+merge_constraints([#constraint{c=C,e=E}|T], Cacc0, Eacc0) ->
+    Eacc = case E of
+	       undefined -> Eacc0;
+	       E -> [E|Eacc0]
+	   end,
+    Cacc = [C|Cacc0],
+    merge_constraints(T, Cacc, Eacc);
+merge_constraints([], Cacc, []) ->
     lists:reverse(Cacc);
-merge_constraints([],Cacc,Eacc) ->
-%%    lists:flatten(Cacc) ++ [{'Errors',Eacc}].
-    lists:reverse(Cacc) ++ [{'Errors',Eacc}].
-
-
-fixup_constraint(C) ->
-    case C of
-	{'SingleValue',SubType} when element(1,SubType) == 'ContainedSubtype' ->
-	    SubType;
-	{'SingleValue',V} when is_list(V) ->
-	    C;
-	%%	    [C,{'ValueRange',{lists:min(V),lists:max(V)}}]; 
-	%% bug, turns wrong when an element in V is a reference to a defined value
-	{'PermittedAlphabet',{'SingleValue',V}} when is_list(V) ->
-	    %%sort and remove duplicates
-	    V2 = {'SingleValue',
-		  ordsets:from_list(lists:flatten(V))},
-	    {'PermittedAlphabet',V2};
-	{'PermittedAlphabet',{'SingleValue',V}} ->
-	    V2 = {'SingleValue',[V]},
-	    {'PermittedAlphabet',V2};
-	{'SizeConstraint',Sc} ->
-	    {'SizeConstraint',fixup_size_constraint(Sc)};
-	
-	List when is_list(List) ->  %% In This case maybe a union or intersection
-	    [fixup_constraint(Xc)||Xc <- List];
-	Other ->
-	    Other
-    end.
-
-fixup_size_constraint({'ValueRange',{Lb,Ub}}) ->
-	{Lb,Ub};
-fixup_size_constraint({{'ValueRange',R},[]}) ->
-	{R,[]};
-fixup_size_constraint({[],{'ValueRange',R}}) ->
-	{[],R};
-fixup_size_constraint({{'ValueRange',R1},{'ValueRange',R2}}) ->
-	{R1,R2};
-fixup_size_constraint({'SingleValue',[Sv]}) ->
-	fixup_size_constraint({'SingleValue',Sv});
-fixup_size_constraint({'SingleValue',L}) when is_list(L) ->
-	ordsets:from_list(L);
-fixup_size_constraint({'SingleValue',L}) ->
-	{L,L};
-fixup_size_constraint({'SizeConstraint',C}) ->
-    %% this is a second SIZE
-    fixup_size_constraint(C);
-fixup_size_constraint({C1,C2}) ->
-    %% this is with extension marks
-    {turn2vr(fixup_size_constraint(C1)), extension_size(fixup_size_constraint(C2))};
-fixup_size_constraint(CList) when is_list(CList) ->
-    [fixup_constraint(Xc)||Xc <- CList].
-   
-turn2vr(L) when is_list(L) ->
-    L2 =[X||X<-ordsets:from_list(L),is_integer(X)],
-    case L2 of
-	[H|_] ->
-	    {H,hd(lists:reverse(L2))};
-	_ ->
-	    L
-    end;
-turn2vr(VR) ->
-    VR.
-extension_size({I,I}) ->
-    [I];
-extension_size({I1,I2}) ->
-    [I1,I2];
-extension_size(C) ->
-    C.
+merge_constraints([], Cacc, Eacc) ->
+    lists:reverse(Cacc) ++ [{element_set,{'Errors',Eacc},none}].
 
 get_line({_,Pos,Token}) when is_integer(Pos),is_atom(Token) ->
     Pos;