1/*  Part of SWI-Prolog
    2
    3    Author:        Jan Wielemaker
    4    E-mail:        J.Wielemaker@vu.nl
    5    WWW:           http://www.swi-prolog.org
    6    Copyright (c)  2011-2019, VU University Amsterdam
    7                              CWI, Amsterdam
    8    All rights reserved.
    9
   10    Redistribution and use in source and binary forms, with or without
   11    modification, are permitted provided that the following conditions
   12    are met:
   13
   14    1. Redistributions of source code must retain the above copyright
   15       notice, this list of conditions and the following disclaimer.
   16
   17    2. Redistributions in binary form must reproduce the above copyright
   18       notice, this list of conditions and the following disclaimer in
   19       the documentation and/or other materials provided with the
   20       distribution.
   21
   22    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   23    "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   24    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
   25    FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
   26    COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
   27    INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
   28    BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
   29    LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
   30    CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   31    LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
   32    ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   33    POSSIBILITY OF SUCH DAMAGE.
   34*/
   35
   36:- module(prolog_history,
   37          [ prolog_history/1
   38          ]).   39:- autoload(library(base32),[base32/2]).   40:- autoload(library(lists),[member/2]).   41:- autoload(library(readutil),[read_line_to_codes/2]).   42
   43
   44:- multifile
   45    prolog:history/2.

   61:- create_prolog_flag(save_history, true, [type(boolean)]).

 history_directory(-Dir) is semidet

Dir is the directory where the per-directory history databases are stored.

   68history_directory(Dir) :-
   69    absolute_file_name(user_app_config('dir-history'),
   70                       Dir,
   71                       [ access(write),
   72                         file_type(directory),
   73                         file_errors(fail)
   74                       ]),
   75    !.
   76history_directory(Dir) :-
   77    absolute_file_name(user_app_config('.'),
   78                       ConfigDir,
   79                       [ access(write),
   80                         file_type(directory),
   81                         file_errors(fail)
   82                       ]),
   83    atom_concat(ConfigDir, '/dir-history', Dir),
   84    (   exists_directory(Dir)
   85    ->  '$my_file'(Dir)
   86    ;   file_directory_name(Dir, Parent),
   87        '$my_file'(Parent),
   88        make_directory(Dir)
   89    ).

 dir_history_file(+Dir, -File) is det

dir_history_file(?Dir, ?File) is nondet

File is the history file for a Prolog session running in Dir.

   96dir_history_file(Dir, File) :-
   97    nonvar(Dir),
   98    !,
   99    history_directory(Base),
  100    absolute_file_name(Dir, Path),
  101    base32(Path, Encoded),
  102    atomic_list_concat([Base, Encoded], /, File).
  103dir_history_file(Dir, File) :-
  104    history_directory(HDir),
  105    directory_files(HDir, Files),
  106    '$member'(Base32, Files),
  107    base32(Dir, Base32),
  108    !,
  109    atomic_list_concat([Dir, Base32], /, File).
  110
  111write_history(File) :-
  112    current_prolog_flag(save_history, true),
  113    catch(prolog:history(user_input, save(File)), _, true), !.
  114write_history(_).

 prolog_history(+Action) is det

Execute Action on the history. Action is one of

enable

Enable history. First loads history for the current directory. Loading the history is done at most once.

disable

Sets the Prolog flag save_history to false, such that the history is not saved on halt.

  128:- dynamic
  129    history_loaded/1.  130
  131load_dir_history(File) :-
  132    (   exists_file(File),
  133        prolog:history(user_input, load(File))
  134    ->  assertz(history_loaded(File))
  135    ;   true
  136    ).
  137
  138prolog_history(enable) :-
  139    history_loaded(_),
  140    !.
  141prolog_history(enable) :-
  142    catch(dir_history_file('.', File), E,
  143          (print_message(warning, E),fail)),
  144    catch(load_dir_history(File), E,
  145          print_message(warning, E)),
  146    !,
  147    at_halt(write_history(File)),
  148    set_prolog_flag(save_history, true).
  149prolog_history(_) :-
  150    set_prolog_flag(save_history, false).
  151
  152		 /*******************************
  153		 *      SWIPL-WIN SUPPORT	*
  154		 *******************************/
  155
  156:- if(current_predicate('$rl_history'/1)).  157prolog:history(_, load(File)) :-
  158    access_file(File, read),
  159    !,
  160    setup_call_cleanup(
  161        open(File, read, In, [encoding(utf8)]),
  162        read_history(In),
  163        close(In)).
  164prolog:history(_, load(_)).
  165
  166read_history(In) :-
  167    repeat,
  168    read_line_to_codes(In, Codes),
  169    (   Codes == end_of_file
  170    ->  !
  171    ;   atom_codes(Line, Codes),
  172        rl_add_history(Line),
  173        fail
  174    ).
  175
  176prolog:history(_, save(File)) :-
  177    '$rl_history'(Lines),
  178    (   Lines \== []
  179    ->  setup_call_cleanup(
  180            open(File, write, Out, [encoding(utf8)]),
  181            forall(member(Line, Lines),
  182                   format(Out, '~w~n', [Line])),
  183            close(Out))
  184    ;   true
  185    ).
  186
  187:- endif.