/* Part of SWI-Prolog Author: Jan Wielemaker E-mail: J.Wielemaker@vu.nl WWW: http://www.swi-prolog.org Copyright (c) 2010-2014, 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(sicstus, [ (block)/1, % +Heads if/3, % :If, :Then, :Else use_module/3, % ?Module, ?File, +Imports bb_put/2, % :Key, +Value bb_get/2, % :Key, -Value bb_delete/2, % :Key, -Value bb_update/3, % :Key, -Old, +New is_mutable/1, % @Term create_mutable/2, % ?Value, -Mutable get_mutable/2, % ?Value, +Mutable update_mutable/2, % ?Value, !Mutable sicstus_is_readable_stream/1, % +Stream read_line/1, % -Codes read_line/2, % +Stream, -Codes trimcore/0, % call_residue/2, % :Goal, -Residue prolog_flag/3, % +Flag, -Old, +New statistics/2, % ?Key, ?Value op(1150, fx, (block)), op(1150, fx, (mode)), op(900, fy, (spy)), op(900, fy, (nospy)) ]). :- use_module(sicstus/block). :- use_module(library(occurs)). :- use_module(library(debug)). :- use_module(library(error)). :- use_module(library(lists)). :- use_module(library(arithmetic)). /** SICStus 3 compatibility library This library is intended to be activated using the directive below in files that are designed for use with SICStus Prolog 3. The changes are in effect until the end of the file and in each file loaded from this file. == :- expects_dialect(sicstus). == This library only provides compatibility with version 3 of SICStus Prolog. For SICStus Prolog 4 compatibility, use library(dialect/sicstus4) instead. @tbd The dialect-compatibility packages are developed in a `demand-driven' fashion. Please contribute to this package. */ % SICStus built-in operators that SWI doesn't declare by default. :- op(1150, fx, user:(mode)). :- op(900, fy, user:(spy)). :- op(900, fy, user:(nospy)). :- multifile system:goal_expansion/2. /******************************* * LIBRARY SETUP * *******************************/ %% push_sicstus_library % % Pushes searching for dialect/sicstus in front of every library % directory that contains such as sub-directory. push_sicstus_library :- ( absolute_file_name(library(dialect/sicstus), Dir, [ file_type(directory), access(read), solutions(all), file_errors(fail) ]), asserta((user:file_search_path(library, Dir) :- prolog_load_context(dialect, sicstus))), fail ; true ). :- push_sicstus_library. in_sicstus_dialect :- ( prolog_load_context(dialect, sicstus) -> true ; prolog_load_context(dialect, sicstus4) ). /******************************* * OPERATORS * *******************************/ % declare all operators globally user:goal_expansion(op(Pri,Ass,Name), op(Pri,Ass,user:Name)) :- \+ qualified(Name), in_sicstus_dialect. qualified(Var) :- var(Var), !, fail. qualified(_:_). % Import all operators from a module, even when using an explicit list % of imports. This simulates the SICStus behavior, where operators are % not module-sensitive and don't need to be listed in import lists. user:goal_expansion(use_module(Module,Imports), use_module(Module,[op(_,_,_)|Imports])) :- in_sicstus_dialect, % Prevent infinite recursion. \+ memberchk(op(_,_,_),Imports). %% setup_dialect % % Further dialect initialization. % % Currently this disables quoting when printing atoms, % which SWI does by default, but SICStus doesn't. % This globally modifies the print_write_options Prolog flag, % so this change also affects code that doesn't request % SICStus compatibility. setup_dialect :- current_prolog_flag(print_write_options, Options), ( selectchk(quoted(true), Options, OptionsNoQuoted) -> set_prolog_flag(print_write_options, OptionsNoQuoted) ; true ). /******************************* * CONTROL * *******************************/ :- meta_predicate if(0,0,0). system:goal_expansion(if(If,Then,Else), (If *-> Then ; Else)) :- in_sicstus_dialect, \+ (sub_term(X, [If,Then,Else]), X == !). %% if(:If, :Then, :Else) % % Same as SWI-Prolog soft-cut construct. Normally, this is % translated using goal-expansion. If either term contains a !, we % use meta-calling for full compatibility (i.e., scoping the cut). if(If, Then, Else) :- ( If *-> Then ; Else ). /******************************* * LIBRARY MODULES * *******************************/ %% rename_module(?SICStusModule, ?RenamedSICSTusModule) is nondet. % % True if RenamedSICSTusModule is the name that we use for the % SICStus native module SICStusModule. We do this in places where % the module-name conflicts. All explicitely qualified goals are % mapped to the SICStus equivalent of the module. :- multifile rename_module/2. system:goal_expansion(M:Goal, SicstusM:Goal) :- atom(M), rename_module(M, SicstusM), prolog_load_context(dialect, sicstus). /******************************* * MODULES * *******************************/ % SICStus use_module/1 does not require the target to be a module. system:goal_expansion(use_module(File), load_files(File, [if(changed)])) :- prolog_load_context(dialect, sicstus). %% use_module(+Module, -File, +Imports) is det. %% use_module(-Module, +File, +Imports) is det. % % This predicate can be used to import from a named module while % the file-location of the module is unknown or to get access to % the module-name loaded from a file. % % If both Module and File are given, we use Module and try to % unify File with the absolute canonical path to the file from % which Module was loaded. However, we succeed regardless of the % success of this unification. use_module(Module, File, Imports) :- atom(Module), !, module_property(Module, file(Path)), use_module(Path, Imports), ignore(File = Path). use_module(Module, File, Imports) :- ground(File), !, absolute_file_name(File, Path, [ file_type(prolog), access(read) ]), use_module(Path, Imports), module_property(Module, file(Path)). use_module(Module, _, _Imports) :- instantiation_error(Module). /******************************* * FOREIGN RESOURCES * *******************************/ /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - SICStus uses foreign_resource(Name, Functions) and predicate definitions similar to Quintus. qpforeign can generate the glue code that can be linked with swipl-ld. This part of the emulation merely skips the declarations and Maps load_foreign_resource to load_foreign_resource/2 from library(qpforeign). - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */ system:term_expansion( (:- load_foreign_resource(Base)), (:- initialization(load_foreign_resource(M:Base, Source), now))) :- prolog_load_context(source, Source), prolog_load_context(module, M). system:term_expansion( (:- module(Name, Exports, Options)), [ (:- module(Name, Exports)) | Declarations ]) :- (prolog_load_context(dialect, sicstus) ; prolog_load_context(dialect, sicstus4)), phrase(sicstus_module_decls(Options), Declarations). sicstus_module_decls([]) --> []. sicstus_module_decls([H|T]) --> sicstus_module_decl(H), sicstus_module_decls(T). sicstus_module_decl(hidden(true)) --> !, [(:- set_prolog_flag(generate_debug_info, false))]. sicstus_module_decl(_) --> []. /******************************* * BB_* * *******************************/ :- meta_predicate bb_put(:, +), bb_get(:, -), bb_delete(:, -), bb_update(:, -, +). system:goal_expansion(bb_put(Key, Value), nb_setval(Atom, Value)) :- bb_key(Key, Atom). system:goal_expansion(bb_get(Key, Value), nb_current(Atom, Value)) :- bb_key(Key, Atom). system:goal_expansion(bb_delete(Key, Value), ( nb_current(Atom, Value), nb_delete(Atom) )) :- bb_key(Key, Atom). system:goal_expansion(bb_update(Key, Old, New), ( nb_current(Atom, Old), nb_setval(Atom, New) )) :- bb_key(Key, Atom). bb_key(Module:Key, Atom) :- atom(Module), !, atomic(Key), atomic_list_concat([Module, Key], :, Atom). bb_key(Key, Atom) :- atomic(Key), prolog_load_context(module, Module), atomic_list_concat([Module, Key], :, Atom). %% bb_put(:Name, +Value) is det. %% bb_get(:Name, -Value) is semidet. %% bb_delete(:Name, -Value) is semidet. %% bb_update(:Name, -Old, +New) is semidet. % % SICStus compatible blackboard routines. The implementations only % deal with cases where the module-sensitive key is unknown and % meta-calling. Simple cases are directly mapped to SWI-Prolog % non-backtrackable global variables. bb_put(Key, Value) :- bb_key(Key, Name), nb_setval(Name, Value). bb_get(Key, Value) :- bb_key(Key, Name), nb_current(Name, Value). bb_delete(Key, Value) :- bb_key(Key, Name), nb_current(Name, Value), nb_delete(Name). bb_update(Key, Old, New) :- bb_key(Key, Name), nb_current(Name, Old), nb_setval(Name, New). /******************************* * MUTABLES * *******************************/ %% is_mutable(@Term) is det. % % True if Term is bound to a mutable term. % % @compat sicstus is_mutable(Term) :- nonvar(Term), functor(Term, '$mutable', 2). %% create_mutable(?Value, -Mutable) is det. % % Create a mutable term with the given initial Value. % % @compat sicstus create_mutable(Value, '$mutable'(Value,_)). %% get_mutable(?Value, +Mutable) is semidet. % % True if Value unifies with the current value of Mutable. % % @compat sicstus get_mutable(Value, '$mutable'(Value,_)). %% update_mutable(?Value, !Mutable) is det. % % Set the value of Mutable to Value. The old binding is % restored on backtracking. % % @see setarg/3. % @compat sicstus update_mutable(Value, Mutable) :- functor(Mutable, '$mutable', 2), !, setarg(1, Mutable, Value). update_mutable(_, Mutable) :- type_error(mutable, Mutable). /******************************* * LINE READING * *******************************/ %% read_line(-Codes) is det. %% read_line(+Stream, -Codes) is det. % % Read a line from the given or current input. The line read does % _not_ include the line-termination character. Unifies Codes with % =end_of_file= if the end of the input is reached. % % @compat sicstus % @see The SWI-Prolog primitive is read_line_to_codes/2. read_line(Codes) :- read_line_to_codes(current_input, Codes). read_line(Stream, Codes) :- read_line_to_codes(Stream, Codes). % Emulate the SICStus behavior of at_end_of_stream, which silently fails % instead of blocking if reading from the stream would block. % Also fails silently if Stream is not actually a valid stream. sicstus_is_readable_stream(Stream) :- is_stream(Stream), stream_property(Stream, end_of_stream(not)). user:goal_expansion(at_end_of_stream(Stream), \+ sicstus_is_readable_stream(Stream)) :- in_sicstus_dialect. user:goal_expansion(at_end_of_stream, \+ sicstus_is_readable_stream(current_input)) :- in_sicstus_dialect. /******************************* * COROUTINING & CONSTRAINTS * *******************************/ /* This is more complicated. Gertjan van Noord decided to use copy_term/3 in Alpino. %% call_residue(:Goal, -Residue) is nondet. % % Residue is a list of VarSet-Goal. Note that this implementation % is incomplete. Please consult the documentation of % call_residue_vars/2 for known issues. :- meta_predicate call_residue(0, -). call_residue(Goal, Residue) :- call_residue_vars(Goal, Vars), ( Vars == [] -> Residue = [] ; copy_term(Vars, _AllVars, Goals), phrase(vars_by_goal(Goals), Residue) ). vars_by_goal((A,B)) --> !, vars_by_goal(A), vars_by_goal(B). vars_by_goal(Goal) --> { term_attvars(Goal, AttVars), sort(AttVars, VarSet) }, [ VarSet-Goal ]. */ %% trimcore is det. % % Trims the stacks and releases unused heap memory to the % operating system where possible. Other tasks of the SICStus % trimcore/0 are automatically scheduled by SWI-Prolog. trimcore :- trim_stacks, trim_heap. /******************************* * FLAGS * *******************************/ :- use_module(library(quintus), [prolog_flag/2 as quintus_flag]). %% prolog_flag(+Flag, -Old, +New) is semidet. % % Query and set a Prolog flag. Use the debug/1 topic =prolog_flag= % to find the flags accessed using this predicate. prolog_flag(Flag, Old, New) :- debug(prolog_flag, 'prolog_flag(~q, ~q, ~q)', [Flag, Old, New]), sicstus_flag(Flag, Old), set_prolog_flag(Flag, New). :- public sicstus_flag/2. sicstus_flag(host_type, HostType) :- !, % Not a perfect emulation. SWI's arch flag only contains the % architecture and OS family (e. g. 'x86_64-darwin'), % but SICStus host_type also contains the OS version number % (e. g. 'x86_64-darwin-15.6.0'). % But this works well enough for code that just checks the % architecture/OS part and not the exact version. current_prolog_flag(arch, HostType). sicstus_flag(system_type, Type) :- !, ( current_prolog_flag(saved_program, true) -> Type = runtime ; Type = development ). sicstus_flag(Name, Value) :- quintus_flag(Name, Value). % Replace all current_prolog_flag/2 and prolog_flag/2 calls with % sicstus_flag/2. prolog_flag/2 can also be autoloaded from % library(quintus) - this goal expansion ensures that sicstus_flag/2 % takes priority when SICStus emulation is active. user:goal_expansion(Goal, sicstus:sicstus_flag(Name, Value)) :- nonvar(Goal), (Goal = current_prolog_flag(Name, Value) ; Goal = prolog_flag(Name, Value)), in_sicstus_dialect. % As of SICStus 3.2.11, the following statistics/2 keys are still missing: % * choice statistics(heap, Stats) :- !, system:statistics(program, Stats). statistics(garbage_collection, [Count, Freed, Time]) :- !, % Remove fourth list element (SWI extension). system:statistics(garbage_collection, [Count, Freed, Time|_]). statistics(atoms, [H|T]) :- !, % SWI natively provides two different values under the atoms key: % the number of atoms as a single integer, % and a Quintus/SICStus-compatible list of atom usage statistics. % Which value is returned when calling statistics(atoms, X) % depends on the value of X before the call: % if X is unbound, the single integer is returned, % but if X is already bound to a (usually non-ground) list, % the list of statistics is returned instead. % Here we just force the list to be returned in all cases % if SICStus emulation is active, by forcing the second argument % to be bound to a list. system:statistics(atoms, [H|T]). statistics(Keyword, Value) :- system:statistics(Keyword, Value). /******************************* * ARITHMETIC * *******************************/ % Provide (#)/2 as arithmetic function. Ideally, we should be able to % bind multiple names to built-in functions. This is rather slow. We % could also consider adding # internally, but not turning it into an % operator. :- op(500, yfx, user:(#)). :- arithmetic_function(user:(#)/2). user:(#(X,Y,R)) :- R is xor(X,Y). /******************************* * HACKS * *******************************/ %% prolog:'$breaklevel'(-BreakLevel, Unknown) % % Query the current break-level prolog:'$breaklevel'(BreakLevel, _) :- current_prolog_flag(break_level, BreakLevel), !. prolog:'$breaklevel'(0, _).