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) 2002-2023, University of Amsterdam 7 VU University Amsterdam 8 CWI, Amsterdam 9 SWI-Prolog Solutions b.v. 10 All rights reserved. 11 12 Redistribution and use in source and binary forms, with or without 13 modification, are permitted provided that the following conditions 14 are met: 15 16 1. Redistributions of source code must retain the above copyright 17 notice, this list of conditions and the following disclaimer. 18 19 2. Redistributions in binary form must reproduce the above copyright 20 notice, this list of conditions and the following disclaimer in 21 the documentation and/or other materials provided with the 22 distribution. 23 24 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 25 "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 26 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 27 FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 28 COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 29 INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 30 BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 31 LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 32 CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 33 LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 34 ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35 POSSIBILITY OF SUCH DAMAGE. 36*/ 37 38:- module(files_ex, 39 [ set_time_file/3, % +File, -OldTimes, +NewTimes 40 link_file/3, % +OldPath, +NewPath, +Type 41 chmod/2, % +File, +Mode 42 relative_file_name/3, % ?AbsPath, +RelTo, ?RelPath 43 directory_file_path/3, % +Dir, +File, -Path 44 directory_member/3, % +Dir, -Member, +Options 45 copy_file/2, % +From, +To 46 make_directory_path/1, % +Directory 47 ensure_directory/1, % +Directory 48 copy_directory/2, % +Source, +Destination 49 delete_directory_and_contents/1, % +Dir 50 delete_directory_contents/1 % +Dir 51 ]). 52:- autoload(library(apply), [maplist/2, maplist/3, foldl/4]). 53:- autoload(library(error), 54 [ permission_error/3, 55 must_be/2, 56 domain_error/2, 57 instantiation_error/1 58 ]). 59:- autoload(library(lists), [member/2]). 60:- autoload(library(nb_set), [empty_nb_set/1, add_nb_set/3]). 61:- autoload(library(option), [dict_options/2]).
77:- predicate_options(directory_member/3, 3, 78 [ recursive(boolean), 79 follow_links(boolean), 80 file_type(atom), 81 extensions(list(atom)), 82 file_errors(oneof([fail,warning,error])), 83 access(oneof([read,write,execute])), 84 matches(text), 85 exclude(text), 86 exclude_directory(text), 87 hidden(boolean) 88 ]). 89 90 91:- use_foreign_library(foreign(files)).
now to indicate the current time. Defined options
are:
link()) or removing (unlink()) names.Below are some example queries. The first retrieves the access-time, while the second sets the last-modified time to the current time.
?- set_time_file(foo, [access(Access)], []). ?- set_time_file(foo, [], [modified(now)]).
hard or symbolic.
With some limitations, these functions also work on Windows. First of all, the underlying filesystem must support links. This requires NTFS. Second, symbolic links are only supported in Vista and later.
?- relative_file_name('/home/janw/nice',
'/home/janw/deep/dir/file', Path).
Path = '../../nice'.
?- relative_file_name(Path, '/home/janw/deep/dir/file', '../../nice').
Path = '/home/janw/nice'.
Add a terminating / to get a path relative to a directory, e.g.
?- relative_file_name('/home/janw/deep/dir/file', './', Path).
Path = 'deep/dir/file'.
163relative_file_name(Path, RelTo, RelPath) :- % +,+,- 164 nonvar(Path), 165 !, 166 absolute_file_name(Path, AbsPath), 167 absolute_file_name(RelTo, AbsRelTo), 168 atomic_list_concat(PL, /, AbsPath), 169 atomic_list_concat(RL, /, AbsRelTo), 170 delete_common_prefix(PL, RL, PL1, PL2), 171 to_dot_dot(PL2, DotDot, PL1), 172 ( DotDot == [] 173 -> RelPath = '.' 174 ; atomic_list_concat(DotDot, /, RelPath) 175 ). 176relative_file_name(Path, RelTo, RelPath) :- 177 ( is_absolute_file_name(RelPath) 178 -> Path = RelPath 179 ; file_directory_name(RelTo, RelToDir), 180 directory_file_path(RelToDir, RelPath, Path0), 181 absolute_file_name(Path0, Path) 182 ). 183 184delete_common_prefix([H|T01], [H|T02], T1, T2) :- 185 !, 186 delete_common_prefix(T01, T02, T1, T2). 187delete_common_prefix(T1, T2, T1, T2). 188 189to_dot_dot([], Tail, Tail). 190to_dot_dot([_], Tail, Tail) :- !. 191to_dot_dot([_|T0], ['..'|T], Tail) :- 192 to_dot_dot(T0, T, Tail).
atom_concat(Directory, File, Path), but it ensures
there is exactly one / between the two parts. Notes:
206directory_file_path(Dir, File, Path) :- 207 nonvar(Dir), nonvar(File), 208 !, 209 ( ( is_absolute_file_name(File) 210 ; Dir == '.' 211 ; Dir == '' 212 ) 213 -> Path = File 214 ; sub_atom(Dir, _, _, 0, /) 215 -> atom_concat(Dir, File, Path) 216 ; atomic_list_concat([Dir, /, File], Path) 217 ). 218directory_file_path(Dir, File, Path) :- 219 nonvar(Path), 220 !, 221 ( nonvar(Dir) 222 -> ( ( Dir == '.' 223 -> true 224 ; Dir == '' 225 ), 226 \+ is_absolute_file_name(Path) 227 -> File = Path 228 ; sub_atom(Dir, _, _, 0, /) 229 -> atom_concat(Dir, File, Path) 230 ; atom_concat(Dir, /, TheDir) 231 -> atom_concat(TheDir, File, Path) 232 ) 233 ; nonvar(File) 234 -> atom_concat(Dir0, File, Path), 235 strip_trailing_slash(Dir0, Dir) 236 ; file_directory_name(Path, Dir), 237 file_base_name(Path, File) 238 ). 239directory_file_path(Dir, _, _) :- 240 instantiation_error(Dir). 241 242strip_trailing_slash(Dir0, Dir) :- 243 ( atom_concat(D, /, Dir0), 244 D \== '' 245 -> Dir = D 246 ; Dir = Dir0 247 ).
true (default false), recurse into subdirectoriestrue (default), follow symbolic links.fail, warning or error.
Default is warning. Errors notably happen if a directory is
unreadable or a link points nowhere.true (default), also return hidden files.This predicate is safe against cycles introduced by symbolic links to directories.
The idea for a non-deterministic file search predicate comes from Nicos Angelopoulos.
283directory_member(Directory, Member, Options) :- 284 dict_options(Dict, Options), 285 ( Dict.get(recursive) == true, 286 \+ Dict.get(follow_links) == false 287 -> empty_nb_set(Visited), 288 DictOptions = Dict.put(visited, Visited) 289 ; DictOptions = Dict 290 ), 291 directory_member_dict(Directory, Member, DictOptions). 292 293directory_member_dict(Directory, Member, Dict) :- 294 directory_files(Directory, Files, Dict), 295 member(Entry, Files), 296 \+ special(Entry), 297 directory_file_path(Directory, Entry, AbsEntry), 298 filter_link(AbsEntry, Dict), 299 ( exists_directory(AbsEntry) 300 -> ( filter_dir_member(AbsEntry, Entry, Dict), 301 Member = AbsEntry 302 ; filter_directory(Entry, Dict), 303 Dict.get(recursive) == true, 304 \+ hidden_file(Entry, Dict), 305 no_link_cycle(AbsEntry, Dict), 306 directory_member_dict(AbsEntry, Member, Dict) 307 ) 308 ; filter_dir_member(AbsEntry, Entry, Dict), 309 Member = AbsEntry 310 ). 311 312directory_files(Directory, Files, Dict) :- 313 Errors = Dict.get(file_errors), 314 !, 315 errors_directory_files(Errors, Directory, Files). 316directory_files(Directory, Files, _Dict) :- 317 errors_directory_files(warning, Directory, Files). 318 319errors_directory_files(fail, Directory, Files) :- 320 catch(directory_files(Directory, Files), _, fail). 321errors_directory_files(warning, Directory, Files) :- 322 catch(directory_files(Directory, Files), E, 323 ( print_message(warning, E), 324 fail)). 325errors_directory_files(error, Directory, Files) :- 326 directory_files(Directory, Files). 327 328 329filter_link(File, Dict) :- 330 \+ ( Dict.get(follow_links) == false, 331 read_link(File, _, _) 332 ). 333 334no_link_cycle(Directory, Dict) :- 335 Visited = Dict.get(visited), 336 !, 337 absolute_file_name(Directory, Canonical, 338 [ file_type(directory) 339 ]), 340 add_nb_set(Canonical, Visited, true). 341no_link_cycle(_, _). 342 (Entry, Dict) :- 344 false == Dict.get(hidden), 345 sub_atom(Entry, 0, _, _, '.').
351filter_dir_member(_AbsEntry, Entry, Dict) :- 352 Exclude = Dict.get(exclude), 353 wildcard_match(Exclude, Entry), 354 !, fail. 355filter_dir_member(_AbsEntry, Entry, Dict) :- 356 Include = Dict.get(matches), 357 \+ wildcard_match(Include, Entry), 358 !, fail. 359filter_dir_member(AbsEntry, _Entry, Dict) :- 360 Type = Dict.get(file_type), 361 \+ matches_type(Type, AbsEntry), 362 !, fail. 363filter_dir_member(_AbsEntry, Entry, Dict) :- 364 ExtList = Dict.get(extensions), 365 file_name_extension(_, Ext, Entry), 366 \+ memberchk(Ext, ExtList), 367 !, fail. 368filter_dir_member(AbsEntry, _Entry, Dict) :- 369 Access = Dict.get(access), 370 \+ access_file(AbsEntry, Access), 371 !, fail. 372filter_dir_member(_AbsEntry, Entry, Dict) :- 373 hidden_file(Entry, Dict), 374 !, fail. 375filter_dir_member(_, _, _). 376 377matches_type(directory, Entry) :- 378 !, 379 exists_directory(Entry). 380matches_type(regular, Entry) :- 381 !, 382 exists_file(Entry). 383matches_type(Type, Entry) :- 384 \+ exists_directory(Entry), 385 user:prolog_file_type(Ext, Type), 386 file_name_extension(_, Ext, Entry).
exclude_directory(+GlobPattern) option.393filter_directory(Entry, Dict) :- 394 Exclude = Dict.get(exclude_directory), 395 wildcard_match(Exclude, Entry), 396 !, fail. 397filter_directory(_, _).
405copy_file(From, To) :- 406 destination_file(To, From, Dest), 407 setup_call_cleanup( 408 open(Dest, write, Out, [type(binary)]), 409 copy_from(From, Out), 410 close(Out)). 411 412copy_from(File, Stream) :- 413 setup_call_cleanup( 414 open(File, read, In, [type(binary)]), 415 copy_stream_data(In, Stream), 416 close(In)). 417 418destination_file(Dir, File, Dest) :- 419 exists_directory(Dir), 420 !, 421 file_base_name(File, Base), 422 directory_file_path(Dir, Base, Dest). 423destination_file(Dest, _, Dest).
431make_directory_path(Dir) :- 432 make_directory_path_2(Dir), 433 !. 434make_directory_path(Dir) :- 435 permission_error(create, directory, Dir). 436 437make_directory_path_2(Dir) :- 438 exists_directory(Dir), 439 !. 440make_directory_path_2(Dir) :- 441 atom_concat(RealDir, '/', Dir), 442 RealDir \== '', 443 !, 444 make_directory_path_2(RealDir). 445make_directory_path_2(Dir) :- 446 Dir \== (/), 447 !, 448 file_directory_name(Dir, Parent), 449 make_directory_path_2(Parent), 450 ensure_directory_(Dir).
458ensure_directory(Dir) :- 459 exists_directory(Dir), 460 !. 461ensure_directory(Dir) :- 462 atom_concat(RealDir, '/', Dir), 463 RealDir \== '', 464 !, 465 ensure_directory(RealDir). 466ensure_directory(Dir) :- 467 ensure_directory_(Dir). 468 469ensure_directory_(Dir) :- 470 E = error(existence_error(directory, _), _), 471 catch(make_directory(Dir), E, 472 ( exists_directory(Dir) 473 -> true 474 ; throw(E) 475 )).
485copy_directory(From, To) :- 486 ( exists_directory(To) 487 -> true 488 ; make_directory(To) 489 ), 490 directory_files(From, Entries), 491 maplist(copy_directory_content(From, To), Entries). 492 493copy_directory_content(_From, _To, Special) :- 494 special(Special), 495 !. 496copy_directory_content(From, To, Entry) :- 497 directory_file_path(From, Entry, Source), 498 directory_file_path(To, Entry, Dest), 499 ( exists_directory(Source) 500 -> copy_directory(Source, Dest) 501 ; copy_file(Source, Dest) 502 ). 503 504special(.). 505special(..).
513delete_directory_and_contents(Dir) :- 514 read_link(Dir, _, _), 515 !, 516 delete_file(Dir). 517delete_directory_and_contents(Dir) :- 518 directory_files(Dir, Files), 519 maplist(delete_directory_contents(Dir), Files), 520 E = error(existence_error(directory, _), _), 521 catch(delete_directory(Dir), E, 522 ( \+ exists_directory(Dir) 523 -> true 524 ; throw(E) 525 )). 526 527delete_directory_contents(_, Entry) :- 528 special(Entry), 529 !. 530delete_directory_contents(Dir, Entry) :- 531 directory_file_path(Dir, Entry, Delete), 532 ( exists_directory(Delete) 533 -> delete_directory_and_contents(Delete) 534 ; E = error(existence_error(file, _), _), 535 catch(delete_file(Delete), E, 536 ( \+ exists_file(Delete) 537 -> true 538 ; throw(E))) 539 ).
548delete_directory_contents(Dir) :-
549 directory_files(Dir, Files),
550 maplist(delete_directory_contents(Dir), Files).+Mode, -Mode or
a plain Mode, which adds new permissions, revokes permissions or
sets the exact permissions. Mode itself is an integer, a POSIX
mode name or a list of POSIX mode names. Defines names are suid,
sgid, svtx and all names defined by the regular expression
[ugo]*[rwx]*. Specifying none of "ugo" is the same as specifying
all of them. For example, to make a file executable for the owner
(user) and group, we can use:
?- chmod(myfile, +ugx).
568chmod(File, +Spec) :- 569 must_be(ground, Spec), 570 !, 571 mode_bits(Spec, Bits), 572 file_mode_(File, Mode0), 573 Mode is Mode0 \/ Bits, 574 chmod_(File, Mode). 575chmod(File, -Spec) :- 576 must_be(ground, Spec), 577 !, 578 mode_bits(Spec, Bits), 579 file_mode_(File, Mode0), 580 Mode is Mode0 /\ \Bits, 581 chmod_(File, Mode). 582chmod(File, Spec) :- 583 must_be(ground, Spec), 584 !, 585 mode_bits(Spec, Bits), 586 chmod_(File, Bits). 587 588mode_bits(Spec, Spec) :- 589 integer(Spec), 590 !. 591mode_bits(Name, Bits) :- 592 atom(Name), 593 !, 594 ( file_mode(Name, Bits) 595 -> true 596 ; domain_error(posix_file_mode, Name) 597 ). 598mode_bits(Spec, Bits) :- 599 must_be(list(atom), Spec), 600 phrase(mode_bits(0, Bits), Spec). 601 602mode_bits(Bits0, Bits) --> 603 [Spec], !, 604 ( { file_mode(Spec, B), Bits1 is Bits0\/B } 605 -> mode_bits(Bits1, Bits) 606 ; { domain_error(posix_file_mode, Spec) } 607 ). 608mode_bits(Bits, Bits) --> 609 []. 610 611file_mode(suid, 0o4000). 612file_mode(sgid, 0o2000). 613file_mode(svtx, 0o1000). 614file_mode(Name, Bits) :- 615 atom_chars(Name, Chars), 616 phrase(who_mask(0, WMask0), Chars, Rest), 617 ( WMask0 =:= 0 618 -> WMask = 0o0777 619 ; WMask = WMask0 620 ), 621 maplist(mode_char, Rest, MBits), 622 foldl(or, MBits, 0, Mask), 623 Bits is Mask /\ WMask. 624 625who_mask(M0, M) --> 626 [C], 627 { who_mask(C,M1), !, 628 M2 is M0\/M1 629 }, 630 who_mask(M2,M). 631who_mask(M, M) --> 632 []. 633 634who_mask(o, 0o0007). 635who_mask(g, 0o0070). 636who_mask(u, 0o0700). 637 638mode_char(r, 0o0444). 639mode_char(w, 0o0222). 640mode_char(x, 0o0111). 641 642or(B1, B2, B) :- 643 B is B1\/B2
Extended operations on files
This module provides additional operations on files. This covers both more obscure and possible non-portable low-level operations and high-level utilities.
Using these Prolog primitives is typically to be preferred over using operating system primitives through shell/1 or process_create/3 because (1) there are no potential file name quoting issues, (2) there is no dependency on operating system commands and (3) using the implementations from this library is usually faster. */