--  GHDL Run Time (GRT) - Stupid emulation of readline using stdio
--  Copyright (C) 2022 Tristan Gingold
--
--  This program is free software: you can redistribute it and/or modify
--  it under the terms of the GNU General Public License as published by
--  the Free Software Foundation, either version 2 of the License, or
--  (at your option) any later version.
--
--  This program is distributed in the hope that it will be useful,
--  but WITHOUT ANY WARRANTY; without even the implied warranty of
--  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
--  GNU General Public License for more details.
--
--  You should have received a copy of the GNU General Public License
--  along with this program.  If not, see <gnu.org/licenses>.
--
--  As a special exception, if other files instantiate generics from this
--  unit, or you link this unit with other files to produce an executable,
--  this unit does not by itself cause the resulting executable to be
--  covered by the GNU General Public License. This exception does not
--  however invalidate any other reasons why the executable file might be
--  covered by the GNU Public License.
with Grt.C; use Grt.C;
with Grt.Stdio; use Grt.Stdio;

package body Grt.Readline_None is
   function Readline (Prompt : Ghdl_C_String) return Ghdl_C_String
   is
      Linep : Ghdl_C_String;
      Cap : size_t;
      Len : Positive;
      C : int;
   begin
      C := fputs (To_Address (Prompt), stdout);

      --  Mimic getline(), which is not available on windows.
      Cap := 64;
      Linep := To_Ghdl_C_String (Malloc (Cap));
      if Linep = null then
         return null;
      end if;

      Len := 1;
      loop
         C := fgetc (stdin);
         exit when C < 0 or C = Character'Pos (ASCII.LF);
         Len := Len + 1;
         if size_t (Len) = Cap then
            Cap := Cap * 2;
            Linep := To_Ghdl_C_String (Realloc (To_Address (Linep), Cap));
            if Linep = null then
               return null;
            end if;
         end if;
         Linep (Len - 1) := Character'Val (C);
      end loop;
      Linep (Len) := ASCII.NUL;
      return Linep;
   end Readline;

   procedure Add_History (Line : Ghdl_C_String) is
   begin
      null;
   end Add_History;
end Grt.Readline_None;