/* Part of SWI-Prolog
Author: Jan Wielemaker
E-mail: J.Wielemaker@vu.nl
WWW: http://www.swi-prolog.org
Copyright (c) 1999-2017, University of Amsterdam
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(thread_util,
[ thread_run_interactor/0, % interactor main loop
threads/0, % List available threads
join_threads/0, % Join all terminated threads
interactor/0, % Create a new interactor
interactor/1, % ?Title
thread_has_console/0, % True if thread has a console
attach_console/0, % Create a new console for thread.
attach_console/1, % ?Title
tspy/1, % :Spec
tspy/2, % :Spec, +ThreadId
tdebug/0,
tdebug/1, % +ThreadId
tnodebug/0,
tnodebug/1, % +ThreadId
tprofile/1, % +ThreadId
tbacktrace/1, % +ThreadId,
tbacktrace/2 % +ThreadId, +Options
]).
:- autoload(library(apply),[maplist/3]).
:- autoload(library(backcomp),[thread_at_exit/1]).
:- autoload(library(edinburgh),[nodebug/0]).
:- autoload(library(gui_tracer),[gdebug/0]).
:- autoload(library(lists),[max_list/2]).
:- autoload(library(option),[merge_options/3,option/3]).
:- autoload(library(pce),[send/2]).
:- autoload(library(prolog_stack),
[print_prolog_backtrace/2,get_prolog_backtrace/3]).
:- autoload(library(statistics),[thread_statistics/2,show_profile/1]).
:- autoload(library(thread),[call_in_thread/2]).
:- set_prolog_flag(generate_debug_info, false).
:- module_transparent
tspy/1,
tspy/2.
/** <module> Interactive thread utilities
This library provides utilities that are primarily intended for
interactive usage in a threaded Prolog environment. It allows for
inspecting threads, manage I/O of background threads (depending on the
environment) and manipulating the debug status of threads.
*/
%! threads
%
% List currently known threads with their status.
threads :-
threads(Threads),
print_message(information, threads(Threads)).
threads(Threads) :-
findall(Thread, thread_statistics(_,Thread), Threads).
%! join_threads
%
% Join all terminated threads.
join_threads :-
findall(Ripped, rip_thread(Ripped), AllRipped),
( AllRipped == []
-> true
; print_message(informational, joined_threads(AllRipped))
).
rip_thread(thread{id:id, status:Status}) :-
thread_property(Id, status(Status)),
Status \== running,
\+ thread_self(Id),
thread_join(Id, _).
%! interactor is det.
%! interactor(?Title) is det.
%
% Run a Prolog toplevel in another thread with a new console window.
% If Title is given, this will be used as the window title.
interactor :-
interactor(_).
interactor(Title) :-
thread_self(Me),
thread_create(thread_run_interactor(Me, Title), _Id,
[ detached(true),
debug(false)
]),
thread_get_message(title(Title)).
thread_run_interactor(Creator, Title) :-
set_prolog_flag(query_debug_settings, debug(false, false)),
attach_console(Title),
thread_send_message(Creator, title(Title)),
print_message(banner, thread_welcome),
prolog.
%! thread_run_interactor
%
% Attach a console and run a Prolog toplevel in the current thread.
thread_run_interactor :-
set_prolog_flag(query_debug_settings, debug(false, false)),
attach_console(_Title),
print_message(banner, thread_welcome),
prolog.
%! thread_has_console is semidet.
%
% True when the calling thread has an attached console.
%
% @see attach_console/0
:- dynamic
has_console/4. % Id, In, Out, Err
thread_has_console(main) :- !. % we assume main has one.
thread_has_console(Id) :-
has_console(Id, _, _, _).
thread_has_console :-
current_prolog_flag(break_level, _),
!.
thread_has_console :-
thread_self(Id),
thread_has_console(Id),
!.
%! attach_console is det.
%! attach_console(?Title) is det.
%
% Create a new console and make the standard Prolog streams point to
% it. If not provided, the title is built using the thread id. Does
% nothing if the current thread already has a console attached.
attach_console :-
attach_console(_).
attach_console(_) :-
thread_has_console,
!.
attach_console(Title) :-
thread_self(Id),
( var(Title)
-> console_title(Id, Title)
; true
),
open_console(Title, In, Out, Err),
assert(has_console(Id, In, Out, Err)),
set_stream(In, alias(user_input)),
set_stream(Out, alias(user_output)),
set_stream(Err, alias(user_error)),
set_stream(In, alias(current_input)),
set_stream(Out, alias(current_output)),
enable_line_editing(In,Out,Err),
thread_at_exit(detach_console(Id)).
console_title(Thread, Title) :- % uses tabbed consoles
current_prolog_flag(console_menu_version, qt),
!,
human_thread_id(Thread, Id),
format(atom(Title), 'Thread ~w', [Id]).
console_title(Thread, Title) :-
current_prolog_flag(system_thread_id, SysId),
human_thread_id(Thread, Id),
format(atom(Title),
'SWI-Prolog Thread ~w (~d) Interactor',
[Id, SysId]).
human_thread_id(Thread, Alias) :-
thread_property(Thread, alias(Alias)),
!.
human_thread_id(Thread, Id) :-
thread_property(Thread, id(Id)).
%! open_console(+Title, -In, -Out, -Err) is det.
%
% Open a new console window and unify In, Out and Err with the input,
% output and error streams for the new console.
:- multifile xterm_args/1.
:- dynamic xterm_args/1.
:- if(current_predicate(win_open_console/5)).
open_console(Title, In, Out, Err) :-
thread_self(Id),
regkey(Id, Key),
win_open_console(Title, In, Out, Err,
[ registry_key(Key)
]).
regkey(Key, Key) :-
atom(Key).
regkey(_, 'Anonymous').
:- else.
%! xterm_args(-List) is nondet.
%
% Multifile and dynamic hook that provides (additional) arguments for
% the xterm(1) process opened for additional thread consoles. Each
% solution must bind List to a list of atomic values. All solutions
% are concatenated using append/2 to form the final argument list.
%
% The defaults set the colors to black-on-light-yellow, enable a
% scrollbar, set the font using Xft font pattern and prepares the
% back-arrow key.
xterm_args(['-xrm', '*backarrowKeyIsErase: false']).
xterm_args(['-xrm', '*backarrowKey: false']).
xterm_args(['-fa', 'monospace;pixelsize=11;regular']).
xterm_args(['-fg', '#000000']).
xterm_args(['-bg', '#ffffdd']).
xterm_args(['-sb', '-sl', 1000, '-rightbar']).
open_console(Title, In, Out, Err) :-
findall(Arg, xterm_args(Arg), Args),
append(Args, Argv),
open_xterm(Title, In, Out, Err, Argv).
:- endif.
%! enable_line_editing(+In, +Out, +Err) is det.
%
% Enable line editing for the console. This is by built-in for the
% Windows console. We can also provide it for the X11 xterm(1) based
% console if we use the BSD libedit based command line editor.
:- if((current_prolog_flag(readline, editline),
exists_source(library(editline)))).
enable_line_editing(_In, _Out, _Err) :-
current_prolog_flag(readline, editline),
!,
el_wrap.
:- endif.
enable_line_editing(_In, _Out, _Err).
:- if(current_predicate(el_unwrap/1)).
disable_line_editing(_In, _Out, _Err) :-
el_unwrap(user_input).
:- endif.
disable_line_editing(_In, _Out, _Err).
%! detach_console(+ThreadId) is det.
%
% Destroy the console for ThreadId.
detach_console(Id) :-
( retract(has_console(Id, In, Out, Err))
-> disable_line_editing(In, Out, Err),
close(In, [force(true)]),
close(Out, [force(true)]),
close(Err, [force(true)])
; true
).
/*******************************
* DEBUGGING *
*******************************/
%! tspy(:Spec) is det.
%! tspy(:Spec, +ThreadId) is det.
%
% Trap the graphical debugger on reaching Spec in the specified or
% any thread.
tspy(Spec) :-
spy(Spec),
tdebug.
tspy(Spec, ThreadID) :-
spy(Spec),
tdebug(ThreadID).
%! tdebug is det.
%! tdebug(+Thread) is det.
%
% Enable debug-mode, trapping the graphical debugger on reaching
% spy-points or errors.
tdebug :-
forall(debug_target(Id), thread_signal(Id, gdebug)).
tdebug(ThreadID) :-
thread_signal(ThreadID, gdebug).
%! tnodebug is det.
%! tnodebug(+Thread) is det.
%
% Disable debug-mode in all threads or the specified Thread.
tnodebug :-
forall(debug_target(Id), thread_signal(Id, nodebug)).
tnodebug(ThreadID) :-
thread_signal(ThreadID, nodebug).
debug_target(Thread) :-
thread_property(Thread, status(running)),
thread_property(Thread, debug(true)).
%! tbacktrace(+Thread) is det.
%! tbacktrace(+Thread, +Options) is det.
%
% Print a backtrace for Thread to the stream `user_error` of the
% calling thread. This is achieved by inserting an interrupt into
% Thread using call_in_thread/2. Options:
%
% - depth(+MaxFrames)
% Number of stack frames to show. Default is the current Prolog
% flag `backtrace_depth` or 20.
%
% Other options are passed to get_prolog_backtrace/3.
%
% @bug call_in_thread/2 may not process the event.
tbacktrace(Thread) :-
tbacktrace(Thread, []).
tbacktrace(Thread, Options) :-
merge_options(Options, [clause_references(false)], Options1),
( current_prolog_flag(backtrace_depth, Default)
-> true
; Default = 20
),
option(depth(Depth), Options1, Default),
call_in_thread(Thread, thread_get_prolog_backtrace(Depth, Stack, Options1)),
print_prolog_backtrace(user_error, Stack).
%! thread_get_prolog_backtrace(+Depth, -Stack, +Options)
%
% As get_prolog_backtrace/3, but starts above the C callback, hiding
% the overhead inside call_in_thread/2.
thread_get_prolog_backtrace(Depth, Stack, Options) :-
prolog_current_frame(Frame),
signal_frame(Frame, SigFrame),
get_prolog_backtrace(Depth, Stack, [frame(SigFrame)|Options]).
signal_frame(Frame, SigFrame) :-
prolog_frame_attribute(Frame, clause, _),
!,
( prolog_frame_attribute(Frame, parent, Parent)
-> signal_frame(Parent, SigFrame)
; SigFrame = Frame
).
signal_frame(Frame, SigFrame) :-
( prolog_frame_attribute(Frame, parent, Parent)
-> SigFrame = Parent
; SigFrame = Frame
).
/*******************************
* REMOTE PROFILING *
*******************************/
%! tprofile(+Thread) is det.
%
% Profile the operation of Thread until the user hits a key.
tprofile(Thread) :-
init_pce,
thread_signal(Thread,
( reset_profiler,
profiler(_, true)
)),
format('Running profiler in thread ~w (press RET to show results) ...',
[Thread]),
flush_output,
get_code(_),
thread_signal(Thread,
( profiler(_, false),
show_profile([])
)).
%! init_pce
%
% Make sure XPCE is running if it is attached, so we can use the
% graphical display using in_pce_thread/1.
init_pce :-
current_prolog_flag(gui, true),
!,
call(send(@(display), open)). % avoid autoloading
init_pce.
/*******************************
* HOOKS *
*******************************/
:- multifile
user:message_hook/3.
user:message_hook(trace_mode(on), _, Lines) :-
\+ thread_has_console,
\+ current_prolog_flag(gui_tracer, true),
catch(attach_console, _, fail),
print_message_lines(user_error, '% ', Lines).
:- multifile
prolog:message/3.
prolog:message(thread_welcome) -->
{ thread_self(Self),
human_thread_id(Self, Id)
},
[ 'SWI-Prolog console for thread ~w'-[Id],
nl, nl
].
prolog:message(joined_threads(Threads)) -->
[ 'Joined the following threads'-[], nl ],
thread_list(Threads).
prolog:message(threads(Threads)) -->
thread_list(Threads).
thread_list(Threads) -->
{ maplist(th_id_len, Threads, Lens),
max_list(Lens, MaxWidth),
LeftColWidth is max(6, MaxWidth),
Threads = [H|_]
},
thread_list_header(H, LeftColWidth),
thread_list(Threads, LeftColWidth).
th_id_len(Thread, IdLen) :-
write_length(Thread.id, IdLen, [quoted(true)]).
thread_list([], _) --> [].
thread_list([H|T], CW) -->
thread_info(H, CW),
( {T == []}
-> []
; [nl],
thread_list(T, CW)
).
thread_list_header(Thread, CW) -->
{ _{id:_, status:_, time:_, stacks:_} :< Thread,
!,
HrWidth is CW+18+13+13
},
[ '~|~tThread~*+ Status~tTime~18+~tStack use~13+~tallocated~13+'-[CW], nl ],
[ '~|~`-t~*+'-[HrWidth], nl ].
thread_list_header(Thread, CW) -->
{ _{id:_, status:_} :< Thread,
!,
HrWidth is CW+7
},
[ '~|~tThread~*+ Status'-[CW], nl ],
[ '~|~`-t~*+'-[HrWidth], nl ].
thread_info(Thread, CW) -->
{ _{id:Id, status:Status, time:Time, stacks:Stacks} :< Thread },
!,
[ '~|~t~q~*+ ~w~t~3f~18+~t~D~13+~t~D~13+'-
[ Id, CW, Status, Time.cpu, Stacks.total.usage, Stacks.total.allocated
]
].
thread_info(Thread, CW) -->
{ _{id:Id, status:Status} :< Thread },
!,
[ '~|~t~q~*+ ~w'-
[ Id, CW, Status
]
].