Natools

------------------------------------------------------------------------------
-- Natools.Getopt_Long is a native Ada implementation of getopt_long()      --
-- processor for command line arguments.                                    --
--                                                                          --
-- This package is generic, and its only formal parameter is a descrete     --
-- type supposed to cover all command-line options.                         --
--                                                                          --
-- Option_Definitions objects hold the list of recognized flags. Flags can  --
-- have a single-character short name or a multiple-character long name.    --
-- Moreover, there is no limit to the number of flag names referring to the --
-- same Option_Id value.                                                    --
--                                                                          --
-- Once the Option_Definitions object has been filled with flags recognized --
-- by the client, the actual command-line arguments can be processed,       --
-- using the handler callbacks from a Handlers.Callback'Class object.       --
--                                                                          --
-- Callback subprograms for normal operation are Option, for command-line   --
-- flags identified by their Option_Id, and Argument, for top-level command --
-- line arguments. There are also callbacks for error conditions (missing   --
-- or unexpected argument, unknown option), whose implementation in         --

         Name    : Any_Name);
         --  Raise Option_Error (default error handler).

   end Handlers;



   ---------------------
   -- Option database --
   ---------------------

   type Argument_Requirement is
     (No_Argument, Required_Argument, Optional_Argument);

   type Option_Definitions is tagged private;

   procedure Add_Option
     (Options    : in out Option_Definitions;
      Long_Name  : String;
      Short_Name : Character;
      Has_Arg    : Argument_Requirement;
      Id         : Option_Id);
      --  Add an option with both a short and a long name to the database.

   procedure Add_Option
     (Options    : in out Option_Definitions;
      Long_Name  : String;
      Has_Arg    : Argument_Requirement;
      Id         : Option_Id);
      --  Add an option with only a long name to the database.

   procedure Add_Option
     (Options    : in out Option_Definitions;
      Short_Name : Character;
      Has_Arg    : Argument_Requirement;
      Id         : Option_Id);
      --  Add an option with only a short name to the database.

   procedure Del_Option
     (Options    : in out Option_Definitions;
      Id         : Option_Id);
      --  Remove from the database an option identified by its id.

   procedure Del_Option
     (Options    : in out Option_Definitions;
      Long_Name  : String);
      --  Remove from the database an option identified by its long name.

   procedure Del_Option
     (Options    : in out Option_Definitions;
      Short_Name : Character);
      --  Remove from the database an option identified by its short name.

   function Format_Long_Names
     (Options     : Option_Definitions;
      Id          : Option_Id;
      Separator   : String := ", ";
      Name_Prefix : String := "--")
      return String;
      --  Return a human-readable list of long names for the given option.

   function Format_Names
     (Options           : Option_Definitions;
      Id                : Option_Id;
      Separator         : String := ", ";
      Long_Name_Prefix  : String := "--";
      Short_Name_Prefix : String := "-";
      Short_First       : Boolean := True)
      return String;
      --  Return a human-readable list of all names for the given option.

   function Format_Short_Names
     (Options     : Option_Definitions;
      Id          : Option_Id;
      Separator   : String := ", ";
      Name_Prefix : String := "-")
      return String;
      --  Return a human-readable list of short names for the given option.

   function Get_Long_Name
     (Options    : Option_Definitions;
      Id         : Option_Id;
      Index      : Positive := 1)
      return String;
      --  Return the "Index"th long name for the given option id.
      --  Raise Constraint_Error when Index is not
      --     in range 1 .. Get_Long_Name_Count (Options, Id)

   function Get_Long_Name_Count
     (Options    : Option_Definitions;
      Id         : Option_Id)
      return Natural;
      --  Return the number of long names for the given option id.

   function Get_Short_Name_Count
     (Options    : Option_Definitions;
      Id         : Option_Id)
      return Natural;
      --  Return the number of short names for the given option id.

   function Get_Short_Names
     (Options    : Option_Definitions;
      Id         : Option_Id)
      return String;
      --  Return a string containing the characters for short names for
      --    the given option id.

   procedure Iterate
     (Options : Option_Definitions;
      Process : not null access procedure (Id : Option_Id;
                                           Long_Name : String;
                                           Short_Name : Character;
                                           Has_Arg : Argument_Requirement));
      --  Iterate over all options, starting with options having a short name,
      --    followed by options having only a long name, sorted respectively by
      --    short and long name.
      --  Process is called for each option; for options lacking a long name,
      --    Long_Name is "", and for options lacking a short name, Short_Name
      --    is Character'Val (0).



   --------------------------------------
   -- Command line argument processing --
   --------------------------------------

   procedure Process
     (Options : Option_Definitions;
      Handler : in out Handlers.Callback'Class;
      Posixly_Correct : Boolean := True;
      Long_Only : Boolean := False;
      Argument_Count : not null access function return Natural
        := Ada.Command_Line.Argument_Count'Access;
      Argument : not null access function (Number : Positive) return String
        := Ada.Command_Line.Argument'Access);

   package Long_Option_Maps is
      new Ada.Containers.Indefinite_Ordered_Maps (String, Option);

   package Short_Option_Maps is
      new Ada.Containers.Indefinite_Ordered_Maps (Character, Option);

   type Option_Definitions is tagged record
      By_Long_Name : Long_Option_Maps.Map;
      By_Short_Name : Short_Option_Maps.Map;
   end record;

end Natools.Getopt_Long;