def create_verify_message_procedure( message: Message, context_invariant: Sequence[Expr]) -> UnitPart: specification = ProcedureSpecification( "Verify_Message", [InOutParameter(["Ctx"], "Context")]) return UnitPart( [ SubprogramDeclaration( specification, [ Postcondition( And( Equal( Call("Has_Buffer", [Variable("Ctx")]), Old(Call("Has_Buffer", [Variable("Ctx")])), ), *context_invariant, )), ], ) ], [ SubprogramBody( specification, [], [ CallStatement( "Verify", [Variable("Ctx"), Variable(f.affixed_name)]) for f in message.fields ], ) ], )
def setter_postconditions( self, message: Message, field: Field, field_type: Type ) -> Sequence[Expr]: return [ *[ Call("Invalid", [Name("Ctx"), Name(p.affixed_name)]) for p in message.successors(field) if p != FINAL ], *self.common.valid_path_to_next_field_condition(message, field, field_type), *[ Equal(e, Old(e)) for e in [ Selected("Ctx", "Buffer_First"), Selected("Ctx", "Buffer_Last"), Selected("Ctx", "First"), Call("Predecessor", [Name("Ctx"), Name(field.affixed_name)]), Call("Valid_Next", [Name("Ctx"), Name(field.affixed_name)]), ] + [ Call(f"Get_{p.name}", [Name("Ctx")]) for p in message.definite_predecessors(field) if isinstance(message.types[p], Scalar) ] ], ]
def test_attribute() -> None: assert isinstance(Size("X"), Attribute) assert isinstance(Length("X"), Attribute) assert isinstance(First("X"), Attribute) assert isinstance(Last("X"), Attribute) assert isinstance(Range("X"), Attribute) assert isinstance(Old("X"), Attribute) assert isinstance(Result("X"), Attribute) assert isinstance(Constrained("X"), Attribute) assert First("X") == First(Variable("X")) assert First("X") == First(ID("X")) assert First("X") == First(Variable(ID("X")))
def create_internal_functions( self, message: Message, scalar_fields: Mapping[Field, Scalar] ) -> UnitPart: return UnitPart( [], [ SubprogramBody( ProcedureSpecification( "Set_Field_Value", [ InOutParameter(["Ctx"], "Context"), Parameter(["Val"], "Field_Dependent_Value"), OutParameter(["Fst", "Lst"], self.types.bit_index), ], ), [ *self.common.field_bit_location_declarations(Selected("Val", "Fld")), *self.common.field_byte_location_declarations(), ], [ Assignment("Fst", Name("First")), Assignment("Lst", Name("Last")), CaseStatement( Selected("Val", "Fld"), [ ( Name(f.affixed_name), [ CallStatement( "Insert", [ Selected("Val", f"{f.name}_Value"), Slice( Selected(Selected("Ctx", "Buffer"), "all"), Name("Buffer_First"), Name("Buffer_Last"), ), Name("Offset"), ], ) if f in scalar_fields else NullStatement() ], ) for f in message.all_fields ], ), ], [ Precondition( AndThen( Not(Constrained("Ctx")), Call("Has_Buffer", [Name("Ctx")]), In(Selected("Val", "Fld"), Range("Field")), Call("Valid_Next", [Name("Ctx"), Selected("Val", "Fld")]), self.common.sufficient_space_for_field_condition( Selected("Val", "Fld") ), ForAllIn( "F", Range("Field"), If( [ ( Call( "Structural_Valid", [ Indexed( Selected("Ctx", "Cursors"), Name("F"), ) ], ), LessEqual( Selected( Indexed( Selected("Ctx", "Cursors"), Name("F"), ), "Last", ), Call( "Field_Last", [Name("Ctx"), Selected("Val", "Fld")], ), ), ) ] ), ), ) ), Postcondition( And( Call("Has_Buffer", [Name("Ctx")]), Equal( Name("Fst"), Call("Field_First", [Name("Ctx"), Selected("Val", "Fld")]), ), Equal( Name("Lst"), Call("Field_Last", [Name("Ctx"), Selected("Val", "Fld")]), ), GreaterEqual(Name("Fst"), Selected("Ctx", "First")), LessEqual(Name("Fst"), Add(Name("Lst"), Number(1))), LessEqual( Call(self.types.byte_index, [Name("Lst")]), Selected("Ctx", "Buffer_Last"), ), ForAllIn( "F", Range("Field"), If( [ ( Call( "Structural_Valid", [ Indexed( Selected("Ctx", "Cursors"), Name("F"), ) ], ), LessEqual( Selected( Indexed( Selected("Ctx", "Cursors"), Name("F"), ), "Last", ), Name("Lst"), ), ) ] ), ), *[ Equal(e, Old(e)) for e in [ Selected("Ctx", "Buffer_First"), Selected("Ctx", "Buffer_Last"), Selected("Ctx", "First"), Selected("Ctx", "Cursors"), ] ], ) ), ], ) ], )
def create_scalar_setter_procedures( self, message: Message, scalar_fields: Mapping[Field, Scalar] ) -> UnitPart: def specification(field: Field, field_type: Type) -> ProcedureSpecification: type_name = ( field_type.enum_name if isinstance(field_type, Enumeration) and field_type.always_valid else field_type.name ) return ProcedureSpecification( f"Set_{field.name}", [ InOutParameter(["Ctx"], "Context"), Parameter(["Val"], f"{message.package}.{type_name}"), ], ) return UnitPart( [ SubprogramDeclaration( specification(f, t), [ Precondition( AndThen( *self.setter_preconditions(f), Call( "Field_Condition", [ Name("Ctx"), Aggregate( Name(f.affixed_name), Name("Val") if not isinstance(t, Enumeration) else Call("Convert", [Name("Val")]), ), ], ), Call("Valid", [Name("Val")]) if not isinstance(t, Enumeration) else TRUE, self.common.sufficient_space_for_field_condition( Name(f.affixed_name) ), ) ), Postcondition( And( VALID_CONTEXT, Call("Has_Buffer", [Name("Ctx")]), Call("Valid", [Name("Ctx"), Name(f.affixed_name)]), Equal( Call(f"Get_{f.name}", [Name("Ctx")]), Aggregate(TRUE, Name("Val")) if isinstance(t, Enumeration) and t.always_valid else Name("Val"), ), *self.setter_postconditions(message, f, t), *[ Equal( Call("Cursor", [Name("Ctx"), Name(p.affixed_name)]), Old(Call("Cursor", [Name("Ctx"), Name(p.affixed_name)])), ) for p in message.predecessors(f) ], ) ), ], ) for f, t in scalar_fields.items() ], [ SubprogramBody( specification(f, t), [ ObjectDeclaration( ["Field_Value"], "Field_Dependent_Value", Aggregate( Name(f.affixed_name), Name("Val") if not isinstance(t, Enumeration) else Call("Convert", [Name("Val")]), ), True, ), ObjectDeclaration(["First", "Last"], self.types.bit_index), ], [ CallStatement( "Reset_Dependent_Fields", [Name("Ctx"), Name(f.affixed_name)], ), CallStatement( "Set_Field_Value", [Name("Ctx"), Name("Field_Value"), Name("First"), Name("Last")], ), Assignment( "Ctx", Aggregate( Selected("Ctx", "Buffer_First"), Selected("Ctx", "Buffer_Last"), Selected("Ctx", "First"), Name("Last"), Selected("Ctx", "Buffer"), Selected("Ctx", "Cursors"), ), ), Assignment( Indexed(Selected("Ctx", "Cursors"), Name(f.affixed_name)), NamedAggregate( ("State", Name("S_Valid")), ("First", Name("First")), ("Last", Name("Last")), ("Value", Name("Field_Value")), ( "Predecessor", Selected( Indexed(Selected("Ctx", "Cursors"), Name(f.affixed_name)), "Predecessor", ), ), ), ), Assignment( Indexed( Selected("Ctx", "Cursors"), Call("Successor", [Name("Ctx"), Name(f.affixed_name)]), ), NamedAggregate( ("State", Name("S_Invalid")), ("Predecessor", Name(f.affixed_name)), ), ), ], ) for f, t in scalar_fields.items() ], )
def create_verify_procedure(self, message: Message, context_invariant: Sequence[Expr]) -> UnitPart: specification = ProcedureSpecification( "Verify", [InOutParameter(["Ctx"], "Context"), Parameter(["Fld"], "Field")]) valid_field_condition = And( Call( "Valid_Value", [Variable("Value")], ), Call( "Field_Condition", [ Variable("Ctx"), Variable("Value"), *([ Call( "Field_Length", [Variable("Ctx"), Variable("Fld")]) ] if common.length_dependent_condition(message) else []), ], ), ) set_cursors_statements = [ IfStatement( [( Call("Composite_Field", [Variable("Fld")]), [ Assignment( Indexed(Variable("Ctx.Cursors"), Variable("Fld")), NamedAggregate( ("State", Variable("S_Structural_Valid")), ( "First", Call("Field_First", [Variable("Ctx"), Variable("Fld")]), ), ( "Last", Call("Field_Last", [Variable("Ctx"), Variable("Fld")]), ), ("Value", Variable("Value")), ( "Predecessor", Selected( Indexed(Variable("Ctx.Cursors"), Variable("Fld")), "Predecessor", ), ), ), ) ], )], [ Assignment( Indexed(Variable("Ctx.Cursors"), Variable("Fld")), NamedAggregate( ("State", Variable("S_Valid")), ("First", Call("Field_First", [Variable("Ctx"), Variable("Fld")])), ("Last", Call("Field_Last", [Variable("Ctx"), Variable("Fld")])), ("Value", Variable("Value")), ( "Predecessor", Selected( Indexed(Variable("Ctx.Cursors"), Variable("Fld")), "Predecessor"), ), ), ) ], ), # WORKAROUND: # Limitation of GNAT Community 2019 / SPARK Pro 20.0 # Provability of predicate is increased by adding part of # predicate as assert PragmaStatement("Assert", [ str(common.message_structure_invariant(message, self.prefix)) ]), # WORKAROUND: # Limitation of GNAT Community 2019 / SPARK Pro 20.0 # Provability of predicate is increased by splitting # assignment in multiple statements IfStatement([( Equal(Variable("Fld"), Variable(f.affixed_name)), [ Assignment( Indexed( Variable("Ctx.Cursors"), Call("Successor", [Variable("Ctx"), Variable("Fld")]), ), NamedAggregate( ("State", Variable("S_Invalid")), ("Predecessor", Variable("Fld")), ), ) ], ) for f in message.fields]), ] return UnitPart( [ SubprogramDeclaration( specification, [ Postcondition( And( Equal( Call("Has_Buffer", [Variable("Ctx")]), Old(Call("Has_Buffer", [Variable("Ctx")])), ), *context_invariant, )), ], ) ], [ SubprogramBody( specification, [ObjectDeclaration(["Value"], "Field_Dependent_Value")], [ IfStatement([( AndThen( Call("Has_Buffer", [Variable("Ctx")]), Call( "Invalid", [ Indexed(Variable("Ctx.Cursors"), Variable("Fld")) ], ), Call("Valid_Predecessor", [Variable("Ctx"), Variable("Fld")]), Call("Path_Condition", [Variable("Ctx"), Variable("Fld")]), ), [ IfStatement( [( Call( "Sufficient_Buffer_Length", [Variable("Ctx"), Variable("Fld")], ), [ Assignment( "Value", Call( "Get_Field_Value", [ Variable("Ctx"), Variable("Fld") ], ), ), IfStatement( [( valid_field_condition, set_cursors_statements, )], [ Assignment( Indexed( Variable( "Ctx.Cursors"), Variable("Fld"), ), NamedAggregate( ( "State", Variable( "S_Invalid" ), ), ( "Predecessor", Variable( FINAL. affixed_name ), ), ), ) ], ), ], )], [ Assignment( Indexed(Variable("Ctx.Cursors"), Variable("Fld")), NamedAggregate( ("State", Variable("S_Incomplete")), ( "Predecessor", Variable( FINAL.affixed_name), ), ), ) ], ) ], )], ) ], ) ], )
def create_internal_functions( self, message: Message, scalar_fields: Mapping[Field, Scalar]) -> UnitPart: return UnitPart( [], [ SubprogramBody( ProcedureSpecification( "Set_Field_Value", [ InOutParameter(["Ctx"], "Context"), Parameter(["Val"], "Field_Dependent_Value"), OutParameter(["Fst", "Lst"], const.TYPES_BIT_INDEX), ], ), [ *common.field_bit_location_declarations( Variable("Val.Fld")), *common.field_byte_location_declarations(), *unique( self.insert_function(common.full_base_type_name(t)) for t in message.types.values() if isinstance(t, Scalar)), ], [ Assignment("Fst", Variable("First")), Assignment("Lst", Variable("Last")), CaseStatement( Variable("Val.Fld"), [( Variable(f.affixed_name), [ CallStatement( "Insert", [ Variable(f"Val.{f.name}_Value"), Slice( Variable("Ctx.Buffer.all"), Variable("Buffer_First"), Variable("Buffer_Last"), ), Variable("Offset"), ], ) if f in scalar_fields else NullStatement() ], ) for f in message.all_fields], ), ], [ Precondition( AndThen( Not(Constrained("Ctx")), Call("Has_Buffer", [Variable("Ctx")]), In(Variable("Val.Fld"), Range("Field")), Call("Valid_Next", [Variable("Ctx"), Variable("Val.Fld")]), common.sufficient_space_for_field_condition( Variable("Val.Fld")), ForAllIn( "F", Range("Field"), If([( Call( "Structural_Valid", [ Indexed( Variable("Ctx.Cursors"), Variable("F"), ) ], ), LessEqual( Selected( Indexed( Variable("Ctx.Cursors"), Variable("F"), ), "Last", ), Call( "Field_Last", [ Variable("Ctx"), Variable("Val.Fld") ], ), ), )]), ), )), Postcondition( And( Call("Has_Buffer", [Variable("Ctx")]), Equal( Variable("Fst"), Call( "Field_First", [Variable("Ctx"), Variable("Val.Fld")]), ), Equal( Variable("Lst"), Call( "Field_Last", [Variable("Ctx"), Variable("Val.Fld")]), ), GreaterEqual(Variable("Fst"), Variable("Ctx.First")), LessEqual(Variable("Fst"), Add(Variable("Lst"), Number(1))), LessEqual( Call(const.TYPES_BYTE_INDEX, [Variable("Lst")]), Variable("Ctx.Buffer_Last"), ), ForAllIn( "F", Range("Field"), If([( Call( "Structural_Valid", [ Indexed( Variable("Ctx.Cursors"), Variable("F"), ) ], ), LessEqual( Selected( Indexed( Variable("Ctx.Cursors"), Variable("F"), ), "Last", ), Variable("Lst"), ), )]), ), *[ Equal(e, Old(e)) for e in [ Variable("Ctx.Buffer_First"), Variable("Ctx.Buffer_Last"), Variable("Ctx.First"), Variable("Ctx.Cursors"), ] ], )), ], ) ] if scalar_fields else [], )
def create_scalar_setter_procedures( self, message: Message, scalar_fields: Mapping[Field, Scalar]) -> UnitPart: def specification(field: Field, field_type: Type) -> ProcedureSpecification: if field_type.package == BUILTINS_PACKAGE: type_name = ID(field_type.name) elif isinstance(field_type, Enumeration) and field_type.always_valid: type_name = common.prefixed_type_name( common.full_enum_name(field_type), self.prefix) else: type_name = common.prefixed_type_name(field_type.identifier, self.prefix) return ProcedureSpecification( f"Set_{field.name}", [ InOutParameter(["Ctx"], "Context"), Parameter(["Val"], type_name) ], ) return UnitPart( [ SubprogramDeclaration( specification(f, t), [ Precondition( AndThen( *self.setter_preconditions(f), Call( "Field_Condition", [ Variable("Ctx"), Aggregate( Variable(f.affixed_name), Call("To_Base", [Variable("Val")]), ), ], ), Call("Valid", [Call("To_Base", [Variable("Val")])]) if not isinstance(t, Enumeration) else TRUE, common.sufficient_space_for_field_condition( Variable(f.affixed_name)), )), Postcondition( And( Call("Has_Buffer", [Variable("Ctx")]), Call("Valid", [ Variable("Ctx"), Variable(f.affixed_name) ]), Equal( Call(f"Get_{f.name}", [Variable("Ctx")]), Aggregate(TRUE, Variable("Val")) if isinstance(t, Enumeration) and t.always_valid else Variable("Val"), ), *self.setter_postconditions(message, f), *[ Equal( Call( "Context_Cursor", [ Variable("Ctx"), Variable(p.affixed_name) ], ), Old( Call( "Context_Cursor", [ Variable("Ctx"), Variable(p.affixed_name) ], )), ) for p in message.predecessors(f) ], )), ], ) for f, t in scalar_fields.items() ], [ SubprogramBody( specification(f, t), [ ObjectDeclaration( ["Field_Value"], "Field_Dependent_Value", Aggregate( Variable(f.affixed_name), Call("To_Base", [Variable("Val")]), ), True, ), ObjectDeclaration(["First", "Last"], const.TYPES_BIT_INDEX), ], [ CallStatement( "Reset_Dependent_Fields", [Variable("Ctx"), Variable(f.affixed_name)], ), CallStatement( "Set_Field_Value", [ Variable("Ctx"), Variable("Field_Value"), Variable("First"), Variable("Last"), ], ), Assignment( "Ctx", Aggregate( Variable("Ctx.Buffer_First"), Variable("Ctx.Buffer_Last"), Variable("Ctx.First"), Variable("Last"), Variable("Ctx.Buffer"), Variable("Ctx.Cursors"), ), ), Assignment( Indexed(Variable("Ctx.Cursors"), Variable(f.affixed_name)), NamedAggregate( ("State", Variable("S_Valid")), ("First", Variable("First")), ("Last", Variable("Last")), ("Value", Variable("Field_Value")), ( "Predecessor", Selected( Indexed(Variable("Ctx.Cursors"), Variable(f.affixed_name)), "Predecessor", ), ), ), ), Assignment( Indexed( Variable("Ctx.Cursors"), Call("Successor", [ Variable("Ctx"), Variable(f.affixed_name) ]), ), NamedAggregate( ("State", Variable("S_Invalid")), ("Predecessor", Variable(f.affixed_name)), ), ), ], ) for f, t in scalar_fields.items() ], )