/* Part of SWI-Prolog
Author: Jan Wielemaker
E-mail: J.Wielemaker@vu.nl
WWW: http://www.swi-prolog.org
Copyright (c) 2011-2017, VU University Amsterdam
All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
2. Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in
the documentation and/or other materials provided with the
distribution.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
POSSIBILITY OF SUCH DAMAGE.
*/
:- module(prolog_history,
[ prolog_history/1
]).
:- use_module(library(base32)).
:- multifile
prolog:history/2.
/** <module> Per-directory persistent commandline history
This module implements persistency of the commandline history over
Prolog sessions on Prolog installations that are based on the GNU
readline library (default for the development version on Unix systems).
The history is stored in the directory =|~/.swipl-dir-history|=. For
each directory for which it keeps the history, there is file whose name
is the base32 encoding of the directory path.
This file is normally loaded when Prolog is started if =user_input= is a
terminal and the system supports history.
*/
:- 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.
history_directory(Dir) :-
absolute_file_name(app_preferences('.swipl-dir-history'),
Dir,
[ access(write),
file_type(directory),
file_errors(fail)
]),
!.
history_directory(Dir) :-
absolute_file_name(app_preferences('.'),
Home,
[ access(write),
file_type(directory),
file_errors(fail)
]),
atom_concat(Home, '/.swipl-dir-history', Dir),
( exists_directory(Dir)
-> fail
; make_directory(Dir)
).
%! 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.
dir_history_file(Dir, File) :-
nonvar(Dir),
!,
history_directory(Base),
absolute_file_name(Dir, Path),
base32(Path, Encoded),
atomic_list_concat([Base, Encoded], /, File).
dir_history_file(Dir, File) :-
history_directory(HDir),
directory_files(HDir, Files),
'$member'(Base32, Files),
base32(Dir, Base32),
!,
atomic_list_concat([Dir, Base32], /, File).
write_history(File) :-
current_prolog_flag(save_history, true),
catch(prolog:history(user_input, save(File)), _, true), !.
write_history(_).
%! prolog_history(+Action) is det.
%
% Execute Action on the history. Action is one of
%
% * enable
% Enable history. First loads history for the current directory.
% Loading the history is done at most once.
% * disable
% Sets the Prolog flag =save_history= to =false=, such that the
% history is not saved on halt.
:- dynamic
history_loaded/1.
load_dir_history(File) :-
( exists_file(File),
prolog:history(user_input, load(File))
-> assertz(history_loaded(File))
; true
).
prolog_history(enable) :-
history_loaded(_),
!.
prolog_history(enable) :-
catch(dir_history_file('.', File), E,
(print_message(warning, E),fail)),
catch(load_dir_history(File), E,
print_message(warning, E)),
!,
at_halt(write_history(File)),
set_prolog_flag(save_history, true).
prolog_history(_) :-
set_prolog_flag(save_history, false).
/*******************************
* SWIPL-WIN SUPPORT *
*******************************/
:- if(current_predicate('$rl_history'/1)).
:- use_module(library(readutil)).
prolog:history(_, load(File)) :-
access_file(File, read),
!,
setup_call_cleanup(
open(File, read, In, [encoding(utf8)]),
read_history(In),
close(In)).
prolog:history(_, load(_)).
read_history(In) :-
repeat,
read_line_to_codes(In, Codes),
( Codes == end_of_file
-> !
; atom_codes(Line, Codes),
rl_add_history(Line),
fail
).
prolog:history(_, save(File)) :-
'$rl_history'(Lines),
( Lines \== []
-> setup_call_cleanup(
open(File, write, Out, [encoding(utf8)]),
forall(member(Line, Lines),
format(Out, '~w~n', [Line])),
close(Out))
; true
).
:- endif.