--- loncom/xml/run.pm 2001/07/20 21:19:38 1.18
+++ loncom/xml/run.pm 2012/12/18 18:27:43 1.61
@@ -1,70 +1,219 @@
package Apache::run;
+#
+# $Id: run.pm,v 1.61 2012/12/18 18:27:43 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/
+#
-sub evaluateold {
- my ($expression,$safeeval,$decls) = @_;
-# print "inside2 evaluate $decls with $expression
\n";
-# gerd's old method interpolates unset vars
-# $safeeval->reval('return qq('.$expression.');');
- unless (defined $expression) { return ''; }
- my $result = '';
- $@='';
- $safeeval->reval('$_=q|'.$expression.'|;');
- if ($@ eq '') {
- $safeeval->reval('{'.$decls.'$_=~s/(\$[A-Za-z]\w*)/(defined(eval($1))?eval($1):$1)/ge;}');
- if ($@ eq '') {
- $result = $safeeval->reval('return $_;');
- } else {
- &Apache::lonxml::error("substitution on:$expression:with:$decls:caused");
- }
- } else {
- &Apache::lonxml::error("defining:$expression:caused");
- }
- if ($@ ne '') {&Apache::lonxml::error($@);}
- return $result
-}
+use HTML::Entities;
-$Apache::run::EVALUATE_STRING=<<'ENDEVALUATE';
- my %oldexpressions=();
- while (!$oldexpressions{$_}) {
- $oldexpressions{$_}=1;
- $_ =~s/((?:\$|\&)(?:[\#|\$]*[A-Za-z][\w]*|\{[A-Za-z][\w]*\}))([\[\{][^\$\&\]\}]+[\]\}])*?(\([^\$\&\)]+\))*?(?=[^\[\{\(]|$)/eval(defined(eval($1.$2))?eval('$1.$2.$3'):'$1.$2.$3')/seg;
- }
+$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) { return $expression; }
- my $result = '';
- $@='';
- $safeeval->reval('{'.$decls.';$_=<<\'EXPRESSION\';'."\n".$expression.
- "\n".'EXPRESSION'."\n".$EVALUATE_STRING.'}');
-# $safeeval->reval('{'.$decls.';<< &evaluate(q|'.$expression.'|);}');
- if ($@ eq '') {
- $result = $safeeval->reval('return $_;');
- chomp $result;
- } else {
- &Apache::lonxml::error("substitution on:$expression:with:$decls:caused $@");
- }
- return $result
+ my ($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 = 'Code ran too long. It ran for more than '.
+ $Apache::lonnet::perlvar{'lonScriptTimeout'}.' seconds';
+ }
+ &Apache::lonxml::error('substitution on '.
+ &HTML::Entities::encode($expression,'<>&"').
+ '
with '.
+ &HTML::Entities::encode($decls,'<>&"').
+ '
caused '.
+ &HTML::Entities::encode($error,'<>&"').' '.
+ &HTML::Entities::encode($innererror,'<>&"').
+ '
');
+ }
+ return $result
}
sub run {
- my ($code,$safeeval,$hideerrors) = @_;
-# print "inside run\n";
- $@='';
- my (@result)=$safeeval->reval($code);
- if ($@ ne '' && !$hideerrors) {
- &Apache::lonxml::error(":$code:caused");
- &Apache::lonxml::error($@);
- }
- if ( $#result < '1') {
- return $result[0];
- } else {
- &Apache::lonxml::debug("Got lots results:$#result:");
- return (@result);
- }
+ 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 = 'Code ran too long. It ran for more than '.
+ $Apache::lonnet::perlvar{'lonScriptTimeout'}.' seconds';
+ }
+ my $errormsg=''.&HTML::Entities::encode($error,'<>&"').' '.
+ &HTML::Entities::encode($innererror,'<>&"').
+ '
occurred while running ';
+ $code=&HTML::Entities::encode($code,'<>&"');
+ if ($innererror=~/line (\d+)/) {
+ my $linenumber=$1;
+ my @code=split("\n",$code);
+ if ($linenumber < scalar(@code)) {
+ $code[$linenumber-1]=''.
+ $code[$linenumber-1].'';
+ }
+ $code=join("\n",@code);
+ }
+ &Apache::lonxml::error($errormsg.$code.'');
+ }
+ if ( $#result < '1') {
+ return $result[0];
+ } else {
+ &Apache::lonxml::debug("Got lots results:$#result:");
+ return (@result);
+ }
+}
+
+sub dump {
+ my ($target,$safeeval)=@_;
+ my $dump='';
+ foreach my $symname (sort keys %{$safeeval->varglob('main::')}) {
+ if (($symname!~ /^(INC|SIG)/) && ($symname!~/\027/) &&
+ ($symname!~/^\_/) && ($symname!~/\:$/)) {
+ 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|
|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
+