--- loncom/xml/run.pm 2000/06/28 13:01:52 1.1
+++ loncom/xml/run.pm 2019/11/10 20:40:59 1.65
@@ -1,9 +1,223 @@
- sub evaluate {
- my ($expression,$safeeval) = @_;
- return $safeeval->reval($expression);
+package Apache::run;
+#
+# $Id: run.pm,v 1.65 2019/11/10 20:40:59 raeburn Exp $
+#
+# Copyright Michigan State University Board of Trustees
+#
+# This file is part of the LearningOnline Network with CAPA (LON-CAPA).
+#
+# LON-CAPA is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# LON-CAPA is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with LON-CAPA; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+#
+# /home/httpd/html/adm/gpl.txt
+#
+# http://www.lon-capa.org/
+#
+
+use HTML::Entities;
+use Apache::lonlocal;
+
+$Apache::run::EVALUATE_STRING=<<'ENDEVALUATE';
+my %_LONCAPA_INTERNAL_oldexpressions=();
+while (!$_LONCAPA_INTERNAL_oldexpressions{$_}) {
+ $_LONCAPA_INTERNAL_oldexpressions{$_}=1;
+ $_ =~s/ # $1 will be the variable reference or subroutine name
+ ((?:\$|\&) #look for a starting $ or &
+ (?:[\#|\$]* #support $$ or $#$ etc.
+ [A-Za-z][\w]*| # get variable name
+ \{[A-Za-z][\w]*\})) # for ${a}
+ # $2 is 0 or more array dereferences []
+ # or hash dereferences {}
+ # the ^$ and ^& is because we do this iteratively
+ # $a[$c] becomes $a[3] which then evaluates
+ ([\[\{][^\$\&\]\}]+[\]\}])*?
+ # $3 is the list of arguments
+ (\([^\$\&\)]+\))*?
+ # only match the above if there is not { [ ( coming up
+ # Why? (I.e. this fails &a(1)[2]
+ (?=[^\[\{\(]|$)/
+ my ($__LC__a,$__LC__b,$__LC__c)=($1,$2,$3);
+ my $__LC__prefix;
+ my $__LC__result;
+ while (1) {
+ if ($__LC__a =~ m-^&(theta|pi|rho)$-) { last; }
+ {
+ use strict;
+ no strict "vars";
+ if (eval(defined(eval($__LC__a.$__LC__b)))) {
+ $__LC__result= $__LC__prefix.eval($__LC__a.$__LC__b.$__LC__c);
+ last;
+ }
+ }
+ $__LC__prefix.=substr($__LC__a,0,1,"");
+ if ($__LC__a!~m-^(\$|&|\#)-) { last; }
+ }
+ if (!defined($__LC__result)) {
+ $__LC__result=$__LC__prefix.$__LC__a.$__LC__b.$__LC__c;
+ }
+ $__LC__result;
+ /sexg;
+ if (scalar(values(%_LONCAPA_INTERNAL_oldexpressions))>10) {last;}
+}
+ENDEVALUATE
+
+sub evaluate {
+ my ($expression,$safeeval,$decls) = @_;
+ unless (defined($expression)) { return ''; }
+ if ($Apache::lonxml::evaluate < 1) { return $expression; }
+ my $result = '';
+ $@='';
+ $Apache::run::timeout=0;
+ local $main::SIG{'ALRM'} = sub {
+ $Apache::run::timeout=1;
+ die("timeout");
+ };
+ my $innererror;
+ eval {
+ &Apache::lonxml::start_alarm();
+ $safeeval->reval('{'.$decls.';$_=<<\'EXPRESSION\';'."\n".$expression.
+ "\n".'EXPRESSION'."\n".$EVALUATE_STRING.'}');
+ $innererror=$@;
+ &Apache::lonxml::end_alarm();
+ };
+ my $error=$@;
+ if ($error eq '' && $innererror eq '' && !$Apache::run::timeout) {
+ $result = $safeeval->reval('return $_;');
+ chomp $result;
+ } else {
+ if ($Apache::run::timeout) {
+ $error =
+ &mt('Code ran too long. It ran for more than [_1] seconds.',
+ $Apache::lonnet::perlvar{'lonScriptTimeout'});
}
+ &Apache::lonxml::error(
+ &mt('Substitution on [_1] with [_2] caused:',
+ '<pre>'. &HTML::Entities::encode($expression,'<>&"').'</pre>',
+ '<pre>'.&HTML::Entities::encode($decls,'<>&"').'</pre>')
+ .'<br />'
+ .'<pre>'.&HTML::Entities::encode($error,'<>&"').' '
+ .&HTML::Entities::encode($innererror,'<>&"').'</pre>');
+ }
+ return $result;
+}
- sub run {
- my ($code,$safeeval) = @_;
- $safeeval->reval($code);
+sub run {
+ my ($code,$safeeval,$hideerrors) = @_;
+ my @result;
+ $@='';
+ $Apache::run::timeout=0;
+ local $main::SIG{'ALRM'} = sub {
+ $Apache::run::timeout=1;
+ die("timeout");
+ };
+ my $innererror;
+ eval {
+ &Apache::lonxml::start_alarm();
+ @result=$safeeval->reval($code);
+ $innererror=$@;
+ &Apache::lonxml::end_alarm();
+ };
+ my $error=$@;
+ if (($Apache::run::timeout || $error ne '' || $innererror ne '') && !$hideerrors) {
+ if ($Apache::run::timeout) {
+ $error = &mt('Code ran too long. It ran for more than [_1] seconds.',
+ $Apache::lonnet::perlvar{'lonScriptTimeout'});
}
+ $code=&HTML::Entities::encode($code,'<>&"');
+ if ($innererror=~/line (\d+)/) {
+ my $linenumber=$1;
+ my @code=split("\n",$code);
+ if ($linenumber < scalar(@code)) {
+ $code[$linenumber-1]=
+ '<span style="color:red;font-weight:bold;">'.
+ $code[$linenumber-1].'</span>';
+ }
+ $code=join("\n",@code);
+ }
+ &Apache::lonxml::error(
+ '<pre>'.&HTML::Entities::encode($error,'<>&"').' '.
+ &HTML::Entities::encode($innererror,'<>&"').
+ '</pre>'
+ .&mt('This occurred while running: [_1]',
+ '<pre>'.$code.'</pre>'));
+ }
+ if ( $#result < '1') {
+ return $result[0];
+ } else {
+ &Apache::lonxml::debug("<b>Got lots results</b>:$#result:");
+ return (@result);
+ }
+}
+
+sub dump {
+ my ($target,$safeeval)=@_;
+ my $dump='';
+ foreach my $symname (sort(keys(%{$safeeval->varglob('main::')}))) {
+ if (($symname!~ /^(INC|SIG)/) && ($symname!~/\027/) && ($symname!~/\022/) &&
+ ($symname!~/^\_/) && ($symname!~/\:$/) && ($symname ne '!')) {
+ my $line;
+ if ($safeeval->reval('defined($'.$symname.')')) {
+ if ($symname =~ /^\w/) {
+ $line.='$'.$symname.'='.$safeeval->reval('$'.$symname)."\n";
+ }
+ }
+ if ($safeeval->reval('@'.$symname)) {
+ $line.='@'.$symname.'=('.
+ $safeeval->reval('join(",",@'.$symname.')').")"."\n";
+ }
+ if ($safeeval->reval('%'.$symname)) {
+ $line.='%'.$symname.'=(';
+ $line.=$safeeval->reval('join(",",map { $_."=>".$'.
+ $symname.'{$_} } sort(keys(%'.
+ $symname.')))').")"."\n";
+ }
+ if ($line ne '') {
+ $line=&HTML::Entities::encode($line,'<>&"');
+ $line=~s|\n|<br />|g;
+ $dump.=$line;
+ }
+ }
+ }
+ $dump.='';
+ return $dump;
+}
+
+1;
+__END__;
+
+=pod
+
+=head1 NAME
+
+Apache::run.pm
+
+=head1 SYNOPSIS
+
+Used to prevent poorly written problems from
+causing lingering after effects
+
+This is part of the LearningOnline Network with CAPA project
+described at http://www.lon-capa.org.
+
+
+=head1 NOTABLE SUBROUTINES
+
+=over
+
+=item run(), dump(), evaluate()
+
+=back
+
+=cut
+