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(swish_debug, 39 [ swish_debug/3, % +Topic, +Format, :Args 40 debug/1, % +Topic 41 nodebug/1, % +Topic 42 swish_debugging/1, % ?Topic 43 list_debug_topics/0, 44 list_debug_topics/1, % +Options 45 46 swish_debug_sentinel/0 47 ]). 48:- autoload(library(option), [option/3, option/2]). 49:- autoload(library(pengines), [pengine_self/1, pengine_output/1]). 50:- autoload(library(dcg/high_order), [sequence/5]). 51:- autoload(library(pengines_io), [pengine_format/2]). 52:- autoload(library(http/html_write), [html/3, print_html/1]). 53 54 55:- meta_predicate 56 debug( , , ). 57 58:- thread_local 59 debugging/2. % Topic, Enabled 60:- dynamic 61 shared_debug_topic/1.
debugging(+Topic)
may be used to
perform more complex debugging tasks. A typical usage skeleton
is:
( debugging(mytopic) -> <perform debugging actions> ; true ), ...
The other two calls are intended to examine existing and enabled debugging tokens and are typically not used in user programs.
103swish_debugging(Topic) :-
104 debugging(Topic, true).
nodebug(_)
removes all
topics. Gives a warning if the topic is not defined unless it is
used from a directive. The latter allows placing debug topics at the
start of a (load-)file without warnings.
For debug/1, Topic can be a term Topic > Out
, where Out is
either a stream or stream-alias or a filename (an atom). This
redirects debug information on this topic to the given output. On
Linux systems redirection can be used to make the message appear,
even if the user_error
stream is redefined using
?- debug(Topic > '/proc/self/fd/2').
A platform independent way to get debug messages in the current
console (for example, a swipl-win
window, or login using ssh
to
Prolog running an SSH server from the libssh
pack) is to use:
?- stream_property(S, alias(user_error)), debug(Topic > S).
Do not forget to disable the debugging using nodebug/1 before quitting the console if Prolog must remain running.
132debug(Topic) :- 133 debug(Topic, true). 134nodebug(Topic) :- 135 debug(Topic, false). 136 137debug(Topic, Enabled) :- 138 ( retract(debugging(Topic, _)) 139 -> true 140 ; shared_debug_topic(Topic) 141 -> true 142 ; print_message(warning, debug_no_topic(Topic)) 143 ), 144 assert(debugging(Topic, Enabled)).
151debug_topic(Topic) :- 152 pengine_self(_), 153 !, 154 ( debugging(Registered, _), 155 Registered =@= Topic 156 -> true 157 ; assertz(debugging(Topic, false)) 158 ). 159debug_topic(Topic) :- 160 ( shared_debug_topic(Registered), 161 Registered =@= Topic 162 -> true 163 ; assertz(shared_debug_topic(Topic)) 164 ).
[search(String)]
or a normal option list. Defined options are:
true
) or inactive
(false
).183list_debug_topics :- 184 list_debug_topics([]). 185 186list_debug_topics(Options) :- 187 ( atom(Options) 188 ; string(Options) 189 ), 190 !, 191 list_debug_topics([search(Options)]). 192list_debug_topics(Options) :- 193 option(active(Activated), Options, _), 194 findall(debug_topic(Topic, String, Activated), 195 matching_topic(Topic, String, Activated, Options), 196 Triples), 197 print_message(information, debug_topics(Triples)). 198 199matching_topic(Topic, String, Activated, Options) :- 200 known_debug_topic(Topic, Activated), 201 topic_to_string(Topic, String), 202 ( option(search(Search), Options) 203 -> sub_atom_icasechk(String, _, Search) 204 ; true 205 ). 206 207topic_to_string(Topic, String) :- 208 numbervars(Topic, 0, _, [singletons(true)]), 209 term_string(Topic, String, [quoted(true), numbervars(true)]). 210 211known_debug_topic(Topic, Value) :- 212 debugging(Topic, Value). 213known_debug_topic(Topic, false) :- 214 shared_debug_topic(Topic), 215 \+ debugging(Topic, _). 216 217 218:- multifile 219 prolog_debug_tools:debugging_hook/0. 220 221prolog_debug_toolsdebugging_hook :- 222 ( debugging(_, true) 223 -> list_debug_topics([active(true)]) 224 ).
user_error
, but only prints if Topic is activated through
debug/1. Args is a meta-argument to deal with goal for the
@-command. Output is first handed to the hook
prolog:debug_print_hook/3. If this fails, Format+Args is
translated to text using the message-translation (see
print_message/2) for the term debug(Format, Args)
and then
printed to every matching destination (controlled by debug/1)
using print_message_lines/3.
The message is preceded by '% ' and terminated with a newline.
242swish_debug(Topic, Format, Args) :- 243 debugging(Topic, true), 244 !, 245 print_debug(Topic, Format, Args). 246swish_debug(_, _, _). 247 248 249print_debug(_Topic, _Format, _Args) :- 250 nb_current(swish_debug_printing, true), 251 !. 252print_debug(Topic, Format, Args) :- 253 setup_call_cleanup( 254 nb_setval(swish_debug_printing, true), 255 print_debug_guarded(Topic, Format, Args), 256 nb_delete(swish_debug_printing)). 257 258:- html_meta(send_html( )). 259 260print_debug_guarded(Topic, Format, Args) :- 261 topic_to_string(Topic, String), 262 format(string(Msg0), Format, Args), 263 split_string(Msg0, "", "\n", [Msg]), 264 send_html(\debug_msg(Msg, String)). 265 266send_html(HTML) :- 267 phrase(html(HTML), Tokens), 268 with_output_to(string(HTMlString), print_html(Tokens)), 269 pengine_output(HTMlString). 270 271debug_msg(Msg, Topic) --> 272 html(div(class('debug-msg'), 273 [ span([class('topic'), title('Debug topic')], Topic) 274 | pre([class('msg'), title('Debug message')], Msg) 275 ])). 276 277 278 /******************************* 279 * EXPANSION * 280 *******************************/ 281 282swish_debug_sentinel. 283 284imports_this_module :- 285 prolog_load_context(module, M), 286 predicate_property(M:swish_debug_sentinel, imported_from(swish_debug)), 287 !. 288 289:- multifile 290 user:goal_expansion/2. 291 292usergoal_expansion(debug(Topic, Format, Args), 293 swish_debug(Topic, Format, Args)) :- 294 imports_this_module, 295 debug_topic(Topic). 296usergoal_expansion(debugging(Topic), 297 swish_debugging(Topic)) :- 298 imports_this_module, 299 debug_topic(Topic). 300 301 302 /******************************* 303 * MESSAGES * 304 *******************************/ 305 306:- multifile 307 prolog:message/3. 308 309prologmessage(debug_topics(List)) --> 310 [ ansi(bold, '~w~t ~w~35|~n', ['Debug Topic', 'Activated']), 311 '~`\u2015t~35|'-[], nl 312 ], 313 sequence(debug_topic, [nl], List). 314 315debug_topic(debug_topic(_Topic, TopicString, true)) --> 316 [ ansi(bold, '~s~t \u2714~35|', [TopicString]) ]. 317debug_topic(debug_topic(_Topic, TopicString, false)) --> 318 [ '~s~t -~35|'-[TopicString] ]. 319 320:- multifile 321 sandbox:safe_global_variable/1, 322 sandbox:safe_meta/2. 323 324sandbox:safe_global_variable(swish_debug_printing). 325sandbox:safe_meta(swish_debug:print_debug(_Topic, Format, Args), Calls) :- 326 sandbox:format_calls(Format, Args, Calls)
Print debug messages and test assertions
This library is a SWISH specific replacement for library(debug) that allows for debug/3 messages in SWISH code as well as libraries loaded into SWISH. Unlike library(debug), this library maintains the debug state per thread (Pengine).
This library allows for debug/3 calls inside user programs stored in SWISH as well as libraries preloaded into SWISH. Libraries that wish to enable debugging by SWISH users must include this file rather than library(debug). This may be done dynamically using the following snippet.
*/