IDL to TTCN3 mapping issues

1
IDL to TTCN-3 mapping issues

• due to practical experiences with e.g. Parlay
  IDLs
• some gaps identified
• major issue missing modules scopes in TTCN-3
• consider module declarations
• introduce prefixes for interface definitions
• discriminated unions
• additional aux. record of type needed
• additional type definitions to express link bw.
  union and discr. types.
• sequence max. size mapping missing
• name clashes due to added suffixes (Type,
  Enum, Object, Interfaces)

2
(1) consider module declarations

• to consider module scope
• to avoid name clashes
• -------------------------IDL-------------------
• module identifier1
• typedef long mylong1
• module identifier2
• typedef string mystring2
• typedef mylong1 mylong2
• -------------------------TTCN-------------------
• module identifier1 type long mylong1
• module identifier1__identifier2
• import from identifier1 all
• type iso8859string mystring2
• type identifier1.mylong1 mylong2

3
(2) interface related definitions

• introduce prefixes to consider IDL scopes
• to avoid name clashes
• -------------------------IDL-------------------
• interface identifier
• attribute long attributeId
• void operationname (in string param_value )
  raises ( ExceptionType )
• //... other body definitions ...
• -------------------------TTCN-------------------
• group identifierInterface
• signature identifier__attributeIdGet () return
  long
• signature identifier__attributeIdSet (in long
  identifier__attributeId)
• signature identifier__operationname (in
  iso8859string identifier__param_value) exception
  ( ExceptionType )
• //...other body definitions ...

4
(3) discriminated unions (a) additional aux.
type needed

• in case of sequences used in discr. unions
• additional aux. record of type needed
• union MyUnion switch( long )
• case 0 boolean b
• case 1 char c
• case 2 octet o
• case 3 sequenceltchargt h
• case 4 short s
• type union MyUnionType
• boolean b,
• iso8859string c,
• octetstring o,
• MyUnion__3 h,
• short s

5
(3) discriminated unions (b) link bw. union and
discr. types

• different IDL types map to same TTCN-3
  definitions
• additional types to keep the link information
  (needed at runtime by CORBA adapter
  implementation)
• enum TpUIVariablePartType P_UI_VARIABLE_PART_TIM
  E, P_UI_VARIABLE_PART_DATE
• union TpUIVariableInfo switch(TpUIVariablePartType
  )
• case P_UI_VARIABLE_PART_TIME TpTime
  VariablePartTime
• case P_UI_VARIABLE_PART_DATE TpDate
  VariablePartDate
• ------------------------------NEW in TTCN-3
  -------------------------------
• type TpUIVariablePartType TpUIVariableInfo__Switch
  
• type enumerated TpUIVariableInfo__CasesType
  case_P_UI_VARIABLE_PART_TIME,
  case_P_UI_VARIABLE_PART_DATE

6
(4) mapping for IDL sequence

• Extend the mapping for IDL sequence if a maximum
  size is specified
• We recommend a mapping to record of in TTCN-3
  with limited number
• of elements
• IDL Example
• typedef sequence ltNameComponent, maximum_sizegt
  Name
• TTCN Example
• type record length (0, maximum_size - 1) of
  NameComponent Name

7
(5) name clases due suffixes

• aux. types are declared by adding suffixes
  Type, Enum, Object, Interfaces
• name clashes may occur if constructed types are
  already defined
• e.g. introduce protected suffix _
• -------------------------IDL-------------------
• enum TpUIInfoType P_UI_INFO_DATA,P_UI_INFO_ADDRE
  SS
• union TpUIInfo switch(TpUIInfoType)
• case P_UI_INFO_DATA TpString InfoData
• case P_UI_INFO_ADDRESS TpURL InfoAddress
• -------------------------TTCN-------------------
• type enumerated TpUIInfoType P_UI_INFO_ID,
  P_UI_INFO_DATA, P_UI_INFO_ADDRESS
• type union TpUIInfoType_ instead of standard
  rule TpUIInfoType org__csapi.TpString
  InfoData, org__csapi.TpURL InfoAddress
• type enumerated TpUIInfoEnumType_
  instead of TpUIInfoEnumTypeorg__csapi_TpInt32
  _InfoID, org__csapi_TpString_InfoData,
  org__csapi_TpURL_InfoAddress