/usr/lib/swi-prolog/library/time.pl is in swi-prolog-nox 7.6.4+dfsg-1build1.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 | /* Part of SWI-Prolog
Author: Jan Wielemaker
E-mail: J.Wielemaker@vu.nl
WWW: http://www.swi-prolog.org
Copyright (c) 2002-2015, 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(time,
[ alarm/3, % +Time, :Callable, -Id
alarm/4, % +Time, :Callable, -Id, +Options
alarm_at/3, % +Time, :Callable, -Id
alarm_at/4, % +Time, :Callable, -Id, +Options
remove_alarm/1, % +Id
install_alarm/1, % +Id
install_alarm/2, % +Id, +Time
uninstall_alarm/1, % +Id
current_alarm/4, % ?At, ?:Goal, ?Id, ?Status
call_with_time_limit/2 % +Time, :Callable
]).
:- use_module(library(lists)).
:- set_prolog_flag(generate_debug_info, false).
:- meta_predicate
call_with_time_limit(+, 0),
alarm(+, 0, -),
alarm(+, 0, -, +),
alarm_at(+, 0, -, +),
current_alarm(?, :, ?, ?).
:- predicate_options(alarm/4, 4,
[ remove(boolean),
install(boolean)
]).
/** <module> Time and alarm library
*/
%! alarm(+Time, :Callable, -Id) is det.
%! alarm(+Time, :Callable, -Id, +Options) is det.
%
% Set up an alarm to be signaled Time seconds from now. If the
% alarm expires, Callable is called asynchronously. Callable can
% be used to raise an exception using throw/1 to abort some
% execution.
%
% Options is a list of Name(Value) options. Currently defined
% options are:
%
% * remove(Bool)
% If =true= (default =false=), remove the alarm-event (as
% remove_alarm/1) after it has been fired.
% * install(Bool)
% If =false= (default =true=) do not install the alarm.
% It must be installed separately using install_alarm/1.
%! alarm_at(+Time, :Callable, -Id) is det.
%! alarm_at(+Time, :Callable, -Id, +Options) is det.
%
% As alarm/3 and alarm/4, but schedule the alarm at an absolute
% point in time.
%
% @see date_time_stamp/2.
%! install_alarm(+Id) is det.
%! install_alarm(+Id, +RelTime) is det.
%
% Install an alarm allocated using alarm/4 with the install(false)
% option or de-activated using uninstall_alarm/1. With a given
% RelTime, the alarm is scheduled at the RelTime from now.
% Otherwise it is scheduled on the same (absolute) time on which
% is was created.
%! uninstall_alarm(+Id) is det.
%
% De-activate an alarm. This does _not_ invalidate Id, but ensures
% that the alarm will not fire. The alarm can be rescheduled to
% the original time using install_alarm/1 or to a new time using
% install_alarm/2.
%! remove_alarm(+Id) is det.
%
% Remove an alarm. If it has not yet been fired, it never will.
%! current_alarm(?Time, :Goal, ?Id, ?Status) is nondet.
%
% Enumerate the alarms in the schedule. Time is the absolute time
% the event is scheduled for (see also get_time/1). Goal is the
% goal to execute, Id is the identifier and Status is the
% scheduling status. It takes the value =done= if the alarm has
% been fired, =next= if the event is the next to be executed and
% =scheduled= otherwise.
:- use_foreign_library(foreign(time)).
:- public time_debug/1. % set debugging
%! call_with_time_limit(+Time, :Goal) is semidet.
%
% Call Goal, while watching out for a (wall-time) limit. If this
% limit is exceeded, the exception =time_limit_exceeded= is
% raised. Goal is called as in once/1.
%
% @throws =time_limit_exceeded=
call_with_time_limit(Time, Goal) :-
Time > 0,
!,
setup_call_cleanup(alarm(Time, time_limit_exceeded(Time),
Id, [install(false)]),
run_alarm_goal(Id, Goal),
remove_alarm_notrace(Id)).
call_with_time_limit(_Time, _Goal) :-
throw(time_limit_exceeded).
run_alarm_goal(AlarmID, Goal) :-
install_alarm(AlarmID),
Goal,
!.
time_limit_exceeded(_Time) :-
throw(time_limit_exceeded).
current_alarm(Time, Goal, Id, Status) :-
current_alarms(Time, Goal, Id, Status, List),
member(alarm(Time, Goal, Id, Status), List).
/*******************************
* HANDLE MESSAGES *
*******************************/
:- multifile
prolog:message/3.
prolog:message(time_limit_exceeded) -->
[ 'Time limit exceeded' ].
/*******************************
* ALARM *
*******************************/
:- multifile sandbox:safe_meta_predicate/1.
sandbox:safe_meta_predicate(time:call_with_time_limit/2).
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