--- loncom/xml/run.pm	2001/12/11 15:48:51	1.22
+++ loncom/xml/run.pm	2003/10/01 21:34:53	1.41
@@ -1,6 +1,6 @@
 package Apache::run;
 #
-# $Id: run.pm,v 1.22 2001/12/11 15:48:51 albertel Exp $
+# $Id: run.pm,v 1.41 2003/10/01 21:34:53 albertel Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -25,70 +25,98 @@ package Apache::run;
 # http://www.lon-capa.org/
 #
 
-sub evaluateold {
-  my ($expression,$safeeval,$decls) = @_;
-# print "inside2 evaluate $decls with $expression<br />\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;
+  my %_LONCAPA_INTERNAL_oldexpressions=();
+  while (!$_LONCAPA_INTERNAL_oldexpressions{$_}) {
+    $_LONCAPA_INTERNAL_oldexpressions{$_}=1;
     $_ =~s/((?:\$|\&)(?:[\#|\$]*[A-Za-z][\w]*|\{[A-Za-z][\w]*\}))([\[\{][^\$\&\]\}]+[\]\}])*?(\([^\$\&\)]+\))*?(?=[^\[\{\(]|$)/eval(defined(eval($1.$2))?eval('$1.$2.$3'):'$1.$2.$3')/seg;
+    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;
+    $main::SIG{'ALRM'} = sub {
+	$Apache::run::timeout=1;
+	die("timeout");
+    };
+    my $innererror;
+    eval {
+	alarm($Apache::lonnet::perlvar{'lonScriptTimeout'});
+	$safeeval->reval('{'.$decls.';$_=<<\'EXPRESSION\';'."\n".$expression.
+			 "\n".'EXPRESSION'."\n".$EVALUATE_STRING.'}');
+	$innererror=$@;
+	alarm(0);
+    };
+    my $error=$@;
+    if ($error eq '' && $innererror eq '' && !$Apache::run::timeout) {
+	$result = $safeeval->reval('return $_;');
+	chomp $result;
+    } else {
+	if ($Apache::run::timeout) {
+	    $error = 'Code ran too long. It ran for more than '.
+		Apache->request->server->timeout.' seconds';
+	}
+	&Apache::lonxml::error('substitution on <pre>'.
+			       &HTML::Entities::encode($expression).
+			       '</pre> with <pre>'.
+			       &HTML::Entities::encode($decls).
+			       '</pre> caused <pre>'.
+			       &HTML::Entities::encode($error).' '.
+			       &HTML::Entities::encode($innererror).
+			       '</pre>');
+    }
+    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 $result[0];
-  } else {
-    &Apache::lonxml::debug("<b>Got lots results</b>:$#result:");
-    return (@result);
-  }
+    my ($code,$safeeval,$hideerrors) = @_;
+    my @result;
+    $@='';
+    $Apache::run::timeout=0;
+    $main::SIG{'ALRM'} = sub {
+	$Apache::run::timeout=1;
+	die("timeout");
+    };
+    my $innererror;
+    eval {
+	alarm($Apache::lonnet::perlvar{'lonScriptTimeout'});
+	@result=$safeeval->reval($code);
+	$innererror=$@;
+	alarm(0);
+    };
+    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->request->server->timeout.' seconds';
+	}
+	my $errormsg='<pre>'.&HTML::Entities::encode($error).' '.
+	    &HTML::Entities::encode($innererror).
+	    '</pre> occured while running <pre>';
+	$code=&HTML::Entities::encode($code);
+	if ($innererror=~/line (\d+)/) {
+	    my $linenumber=$1;
+	    my @code=split("\n",$code);
+	    $code[$linenumber-1]='<b><font color="red">'.
+		$code[$linenumber-1].'</font></b>';
+	    $code=join("\n",@code);
+	}
+	&Apache::lonxml::error($errormsg.$code.'</pre>');
+    }
+    if ( $#result < '1') {
+	return $result[0];
+    } else {
+	&Apache::lonxml::debug("<b>Got lots results</b>:$#result:");
+	return (@result);
+    }
 }
 
 sub dump {
@@ -96,19 +124,21 @@ sub dump {
   my $dump='';
   foreach my $symname (sort keys %{$safeeval->varglob('main::')}) {
     if (($symname!~/^\_/) && ($symname!~/\:$/)) {
+      my $line;
       if ($safeeval->reval('defined($'.$symname.')')) {
-	$dump.='$'.$symname.'='.$safeeval->reval('$'.$symname)."\n";
+	$line='$'.$symname.'='.$safeeval->reval('$'.$symname);
       }	
       if ($safeeval->reval('defined(@'.$symname.')')) {
-	$dump.='@'.$symname.'=('.
-	  $safeeval->reval('join(",",@'.$symname.')').")\n";
+	$line='@'.$symname.'=('.
+	  $safeeval->reval('join(",",@'.$symname.')').")";
       }
       if ($safeeval->reval('defined(%'.$symname.')')) {
-	$dump.='%'.$symname.'=(';
-	$dump.=$safeeval->reval('join(",",map { $_."=>".$'.
+	$line='%'.$symname.'=(';
+	$line.=$safeeval->reval('join(",",map { $_."=>".$'.
 				$symname.'{$_} } sort keys %'.
-				$symname.')').")\n";
+				$symname.')').")"
       }
+      if ($line ne '') { $dump.=&HTML::Entities::encode($line)."<br />"; }
     }
   }
   $dump.='';