glfwGetRequiredInstanceExtensions binding demo

// hdr.h
char **strings(int *count);

// bdy.c
#include "hdr.h"

char *data[] = {"now", "is", "the", "time"};

char **strings(int *count) {
  *count = sizeof(data) / sizeof(char*);
  return data;
}

--  caller.adb
with Ada.Text_IO;
with Ada.Unchecked_Conversion;
with Interfaces.C.Strings;
with System;

procedure Caller is
   function Strings return Interfaces.C.Strings.chars_ptr_array;
   function Strings return Interfaces.C.Strings.chars_ptr_array is
      function Inner (Count : out Interfaces.C.int) return System.Address
      with
        Import,
        Convention => C,
        External_Name => "strings";
      Count : aliased Interfaces.C.int;
      Address : System.Address;
   begin
      Address := Inner (Count);
      declare
         subtype Result_Type
           is Interfaces.C.Strings.chars_ptr_array
             (1 .. Interfaces.C.size_t (Count));
         type Result_Type_P is access Result_Type;
         function Convert is new Ada.Unchecked_Conversion (System.Address,
                                                           Result_Type_P);
      begin
         return Result : Result_Type do
            Result := Convert (Address).all;
         end return;
      end;
   end Strings;
   Answer : Interfaces.C.Strings.chars_ptr_array := Strings;
begin
   for Str of Strings loop
      Ada.Text_IO.Put_Line (Interfaces.C.Strings.Value (Str));
   end loop;
end Caller;