--- loncom/lonnet/perl/lonnet.pm	2000/10/07 10:09:53	1.39
+++ loncom/lonnet/perl/lonnet.pm	2000/10/30 22:45:21	1.55
@@ -25,27 +25,33 @@
 # revokecustomrole (udom,uname,url,rdom,rnam,rolename) : Revoke a custom role
 # appenv(hash)       : adds hash to session environment
 # store(hash)        : stores hash permanently for this url
+# cstore(hash)       : critical store
 # restore            : returns hash for this url
 # eget(namesp,array) : returns hash with keys from array filled in from namesp
 # get(namesp,array)  : returns hash with keys from array filled in from namesp
 # del(namesp,array)  : deletes keys out of array from namesp
 # put(namesp,hash)   : stores hash in namesp
+# cput(namesp,hash)  : critical put
 # dump(namesp)       : dumps the complete namespace into a hash
 # ssi(url,hash)      : does a complete request cycle on url to localhost, posts
 #                      hash
 # coursedescription(id) : returns and caches course description for id
 # repcopy(filename)  : replicate file
 # dirlist(url)       : gets a directory listing
+# directcondval(index) : reading condition value of single condition from 
+#                        state string
 # condval(index)     : value of condition index based on state
 # varval(name)       : value of a variable
 # refreshstate()     : refresh the state information string
 # symblist(map,hash) : Updates symbolic storage links
-# symbread(filename) : returns the data handle
+# symbread([filename]) : returns the data handle (filename optional)
 # rndseed()          : returns a random seed  
 # getfile(filename)  : returns the contents of filename, or a -1 if it can't
 #                      be found, replicates and subscribes to the file
 # filelocation(dir,file) : returns a farily clean absolute reference to file 
 #                          from the directory dir
+# hreflocation(dir,file) : same as filelocation, but for hrefs
+# log(domain,user,home,msg) : write to permanent log for user
 #
 # 6/1/99,6/2,6/10,6/11,6/12,6/14,6/26,6/28,6/29,6/30,
 # 7/1,7/2,7/9,7/10,7/12,7/14,7/15,7/19,
@@ -60,7 +66,8 @@
 # 08/22,08/28,08/31,09/01,09/02,09/04,09/05,09/25,09/28,09/30 Gerd Kortemeyer
 # 10/04 Gerd Kortemeyer
 # 10/04 Guy Albertelli
-# 10/06 Gerd Kortemeyer
+# 10/06,10/09,10/10,10/11,10/14,10/20,10/23,10/25,10/26,10/27,10/28,10/29, 
+# 10/30 Gerd Kortemeyer
 
 package Apache::lonnet;
 
@@ -421,7 +428,7 @@ sub ssi {
 
 sub log {
     my ($dom,$nam,$hom,$what)=@_;
-    return reply("log:$dom:$nam:$what",$hom);
+    return critical("log:$dom:$nam:$what",$hom);
 }
 
 # ----------------------------------------------------------------------- Store
@@ -429,7 +436,7 @@ sub log {
 sub store {
     my %storehash=@_;
     my $symb;
-    unless ($symb=escape(&symbread($ENV{'request.filename'}))) { return ''; }
+    unless ($symb=escape(&symbread())) { return ''; }
     my $namespace;
     unless ($namespace=$ENV{'request.course.id'}) { return ''; }
     my $namevalue='';
@@ -442,11 +449,29 @@ sub store {
 		 "$ENV{'user.home'}");
 }
 
+# -------------------------------------------------------------- Critical Store
+
+sub cstore {
+    my %storehash=@_;
+    my $symb;
+    unless ($symb=escape(&symbread())) { return ''; }
+    my $namespace;
+    unless ($namespace=$ENV{'request.course.id'}) { return ''; }
+    my $namevalue='';
+    map {
+        $namevalue.=escape($_).'='.escape($storehash{$_}).'&';
+    } keys %storehash;
+    $namevalue=~s/\&$//;
+    return critical(
+     "store:$ENV{'user.domain'}:$ENV{'user.name'}:$namespace:$symb:$namevalue",
+		 "$ENV{'user.home'}");
+}
+
 # --------------------------------------------------------------------- Restore
 
 sub restore {
     my $symb;
-    unless ($symb=escape(&symbread($ENV{'request.filename'}))) { return ''; }
+    unless ($symb=escape(&symbread())) { return ''; }
     my $namespace;
     unless ($namespace=$ENV{'request.course.id'}) { return ''; }
     my $answer=reply(
@@ -468,12 +493,15 @@ sub restore {
 sub coursedescription {
     my $courseid=shift;
     $courseid=~s/^\///;
+    $courseid=~s/\_/\//g;
     my ($cdomain,$cnum)=split(/\//,$courseid);
     my $chome=homeserver($cnum,$cdomain);
     if ($chome ne 'no_host') {
        my $rep=reply("dump:$cdomain:$cnum:environment",$chome);
        if ($rep ne 'con_lost') {
-	   my %cachehash=();
+           my $normalid=$courseid;
+           $normalid=~s/\//\_/g;
+           my %envhash=();
            my %returnhash=('home'   => $chome, 
                            'domain' => $cdomain,
                            'num'    => $cnum);
@@ -482,14 +510,13 @@ sub coursedescription {
                $name=&unescape($name);
                $value=&unescape($value);
                $returnhash{$name}=$value;
-               if ($name eq 'description') {
-		   $cachehash{$courseid}=$value;
-               }
+               $envhash{'course.'.$normalid.'.'.$name}=$value;
            } split(/\&/,$rep);
            $returnhash{'url'}='/res/'.declutter($returnhash{'url'});
            $returnhash{'fn'}=$perlvar{'lonDaemons'}.'/tmp/'.
 	       $ENV{'user.name'}.'_'.$cdomain.'_'.$cnum;
-	   put ('coursedescriptions',%cachehash);
+           $envhash{'course.'.$normalid.'.last_cache'}=time;
+           &appenv(%envhash);
            return %returnhash;
        }
     }
@@ -527,6 +554,7 @@ sub rolesinit {
                 }
             }
             if (($area ne '') && ($trole ne '')) {
+	       my $spec=$trole.'.'.$area;
                my ($tdummy,$tdomain,$trest)=split(/\//,$area);
                if ($trole =~ /^cr\//) {
 		   my ($rdummy,$rdomain,$rauthor,$rrole)=split(/\//,$trole);
@@ -538,21 +566,27 @@ sub rolesinit {
                       if (($roledef ne 'con_lost') && ($roledef ne '')) {
                          my ($syspriv,$dompriv,$coursepriv)=
 			     split(/\_/,unescape($roledef));
- 	                 $allroles{'/'}.=':'.$syspriv;
+ 	                 $allroles{'cm./'}.=':'.$syspriv;
+                         $allroles{$spec.'./'}.=':'.$syspriv;
                          if ($tdomain ne '') {
-                             $allroles{'/'.$tdomain.'/'}.=':'.$dompriv;
+                             $allroles{'cm./'.$tdomain.'/'}.=':'.$dompriv;
+                             $allroles{$spec.'./'.$tdomain.'/'}.=':'.$dompriv;
                              if ($trest ne '') {
-		                $allroles{$area}.=':'.$coursepriv;
+		                $allroles{'cm.'.$area}.=':'.$coursepriv;
+		                $allroles{$spec.'.'.$area}.=':'.$coursepriv;
                              }
 	                 }
                       }
                    }
                } else {
-	           $allroles{'/'}.=':'.$pr{$trole.':s'};
+	           $allroles{'cm./'}.=':'.$pr{$trole.':s'};
+	           $allroles{$spec.'./'}.=':'.$pr{$trole.':s'};
                    if ($tdomain ne '') {
-                      $allroles{'/'.$tdomain.'/'}.=':'.$pr{$trole.':d'};
+                     $allroles{'cm./'.$tdomain.'/'}.=':'.$pr{$trole.':d'};
+                     $allroles{$spec.'./'.$tdomain.'/'}.=':'.$pr{$trole.':d'};
                       if ($trest ne '') {
-		          $allroles{$area}.=':'.$pr{$trole.':c'};
+		          $allroles{'cm.'.$area}.=':'.$pr{$trole.':c'};
+		          $allroles{$spec.'.'.$area}.=':'.$pr{$trole.':c'};
                       }
 	           }
 	       }
@@ -594,10 +628,11 @@ sub get {
                  $ENV{'user.home'});
    my @pairs=split(/\&/,$rep);
    my %returnhash=();
+   my $i=0;
    map {
-      my ($key,$value)=split(/=/,$_);
-      $returnhash{unescape($key)}=unescape($value);
-   } @pairs;
+      $returnhash{$_}=unescape($pairs[$i]);
+      $i++;
+   } @storearr;
    return %returnhash;
 }
 
@@ -642,6 +677,20 @@ sub put {
                  $ENV{'user.home'});
 }
 
+# ------------------------------------------------------ critical put interface
+
+sub cput {
+   my ($namespace,%storehash)=@_;
+   my $items='';
+   map {
+       $items.=escape($_).'='.escape($storehash{$_}).'&';
+   } keys %storehash;
+   $items=~s/\&$//;
+   return critical
+           ("put:$ENV{'user.domain'}:$ENV{'user.name'}:$namespace:$items",
+                 $ENV{'user.home'});
+}
+
 # -------------------------------------------------------------- eget interface
 
 sub eget {
@@ -655,10 +704,11 @@ sub eget {
                  $ENV{'user.home'});
    my @pairs=split(/\&/,$rep);
    my %returnhash=();
+   my $i=0;
    map {
-      my ($key,$value)=split(/=/,$_);
-      $returnhash{unescape($key)}=unescape($value);
-   } @pairs;
+      $returnhash{$_}=unescape($pairs[$i]);
+      $i++;
+   } @storearr;
    return %returnhash;
 }
 
@@ -666,106 +716,220 @@ sub eget {
 
 sub allowed {
     my ($priv,$uri)=@_;
-    $uri=~s/^\/res//;
-    $uri=~s/^\///;
+    $uri=&declutter($uri);
 
-# Free bre access to adm resources
+# Free bre access to adm and meta resources
 
-    if (($uri=~/^adm\//) && ($priv eq 'bre')) {
+    if ((($uri=~/^adm\//) || ($uri=~/\.meta$/)) && ($priv eq 'bre')) {
 	return 'F';
     }
 
-# Gather priviledges over system and domain
-
     my $thisallowed='';
-    if ($ENV{'user.priv./'}=~/$priv\&([^\:]*)/) {
+    my $statecond=0;
+    my $courseprivid='';
+
+# Course
+
+    if ($ENV{'user.priv.'.$ENV{'request.role'}.'./'}=~/$priv\&([^\:]*)/) {
        $thisallowed.=$1;
     }
-    if ($ENV{'user.priv./'.(split(/\//,$uri))[0].'/'}=~/$priv\&([^\:]*)/) {
+
+# Domain
+
+    if ($ENV{'user.priv.'.$ENV{'request.role'}.'./'.(split(/\//,$uri))[0].'/'}
+       =~/$priv\&([^\:]*)/) {
        $thisallowed.=$1;
     }
 
-# Full access at system or domain level? Exit.
+# Course: uri itself is a course
+
+    if ($ENV{'user.priv.'.$ENV{'request.role'}.'./'.$uri}
+       =~/$priv\&([^\:]*)/) {
+       $thisallowed.=$1;
+    }
+
+# Full access at system, domain or course-wide level? Exit.
 
     if ($thisallowed=~/F/) {
 	return 'F';
     }
 
-# The user does not have full access at system or domain level
-# Course level access control
+# If this is generating or modifying users, exit with special codes
 
-# uri itself refering to a course?
-    
-    if ($uri=~/\.course$/) {
-       if ($ENV{'user.priv./'.$uri}=~/$priv\&([^\:]*)/) {
-          $thisallowed.=$1;
+    if (':csu:cdc:ccc:cin:cta:cep:ccr:cst:cad:cli:cau:cdg:'=~/\:$priv\:/) {
+	return $thisallowed;
+    }
+#
+# Gathered so far: system, domain and course wide priviledges
+#
+# Course: See if uri or referer is an individual resource that is part of 
+# the course
+
+    if ($ENV{'request.course.id'}) {
+       $courseprivid=$ENV{'request.course.id'};
+       if ($ENV{'request.course.sec'}) {
+          $courseprivid.='/'.$ENV{'request.course.sec'};
        }
-# Full access on course level? Exit.
-       if ($thisallowed=~/F/) {
-	  return 'F';
+       $courseprivid=~s/\_/\//;
+       my $checkreferer=1;
+       my @uriparts=split(/\//,$uri);
+       my $filename=$uriparts[$#uriparts];
+       my $pathname=$uri;
+       $pathname=~s/\/$filename$//;
+       if ($ENV{'acc.res.'.$ENV{'request.course.id'}.'.'.$pathname}=~
+           /\&$filename\:([\d\|]+)\&/) {
+           $statecond=$1;
+           if ($ENV{'user.priv.'.$ENV{'request.role'}.'./'.$courseprivid}
+               =~/$priv\&([^\:]*)/) {
+               $thisallowed.=$1;
+               $checkreferer=0;
+           }
        }
 
-# uri is refering to an individual resource; user needs to be in a course
+       if (($ENV{'HTTP_REFERER'}) && ($checkreferer)) {
+	  my $refuri=$ENV{'HTTP_REFERER'};
+          $refuri=~s/^http\:\/\/$ENV{'request.host'}//i;
+          $refuri=&declutter($refuri);
+          my @uriparts=split(/\//,$refuri);
+          my $filename=$uriparts[$#uriparts];
+          my $pathname=$refuri;
+          $pathname=~s/\/$filename$//;
+          my @filenameparts=split(/\./,$uri);
+          if (&fileembstyle($filenameparts[$#filenameparts]) ne 'ssi') {
+            if ($ENV{'acc.res.'.$ENV{'request.course.id'}.'.'.$pathname}=~
+              /\&$filename\:([\d\|]+)\&/) {
+              my $refstatecond=$1;
+              if ($ENV{'user.priv.'.$ENV{'request.role'}.'./'.$courseprivid}
+                  =~/$priv\&([^\:]*)/) {
+                  $thisallowed.=$1;
+                  $uri=$refuri;
+                  $statecond=$refstatecond;
+              }
+            }
+          }
+       }
+   }
 
-   } else {
+#
+# Gathered now: all priviledges that could apply, and condition number
+# 
+#
+# Full or no access?
+#
 
-       unless(defined($ENV{'request.course.id'})) {
-	   return '1';
-       }
+    if ($thisallowed=~/F/) {
+	return 'F';
+    }
 
-# Get access priviledges for course
+    unless ($thisallowed) {
+        return '';
+    }
+
+# Restrictions exist, deal with them
+#
+#   C:according to course preferences
+#   R:according to resource settings
+#   L:unless locked
+#   X:according to user session state
+#
 
-       if ($ENV{'user.priv./'.$ENV{'request.course.id'}}=~/$priv\&([^\:]*)/) {
-          $thisallowed.=$1;
+# Possibly locked functionality, check all courses
+# Locks might take effect only after 10 minutes cache expiration for other
+# courses, and 2 minutes for current course
+
+    my $envkey;
+    if ($thisallowed=~/L/) {
+        foreach $envkey (keys %ENV) {
+           if ($envkey=~/^user\.role\.(st|ta)\.([^\.]*)/) {
+               my $courseid=$2;
+               my $roleid=$1.'.'.$2;
+               my $expiretime=600;
+               if ($ENV{'request.role'} eq $roleid) {
+		  $expiretime=120;
+               }
+	       my ($cdom,$cnum,$csec)=split(/\//,$courseid);
+               my $prefix='course.'.$cdom.'_'.$cnum.'.';
+               if ((time-$ENV{$prefix.'last_cache'})>$expiretime) {
+		   &coursedescription($courseid);
+               }
+               if (($ENV{$prefix.'res.'.$uri.'.lock.sections'}=~/\,$csec\,/)
+                || ($ENV{$prefix.'res.'.$uri.'.lock.sections'} eq 'all')) {
+		   if ($ENV{$prefix.'res.'.$uri.'.lock.expire'}>time) {
+                       &log('Locked by res: '.$priv.' for '.$uri.' due to '.
+                            $cdom.'/'.$cnum.'/'.$csec.' expire '.
+                            $ENV{$prefix.'priv.'.$priv.'.lock.expire'});
+		       return '';
+                   }
+               }
+               if (($ENV{$prefix.'priv.'.$priv.'.lock.sections'}=~/\,$csec\,/)
+                || ($ENV{$prefix.'priv.'.$priv.'.lock.sections'} eq 'all')) {
+		   if ($ENV{'priv.'.$priv.'.lock.expire'}>time) {
+                       &log('Locked by priv: '.$priv.' for '.$uri.' due to '.
+                            $cdom.'/'.$cnum.'/'.$csec.' expire '.
+                            $ENV{$prefix.'priv.'.$priv.'.lock.expire'});
+		       return '';
+                   }
+               }
+	   }
        }
+    }
+   
+#
+# Rest of the restrictions depend on selected course
+#
 
-# See if resource or referer is part of this course
-          
-       my @uriparts=split(/\//,$uri);
-       my $urifile=$uriparts[$#uriparts];
-       $urifile=~/\.(\w+)$/;
-       my $uritype=$1;
-       $#uriparts--;
-       my $uripath=join('/',@uriparts);
-       my $uricond=-1;
-       if ($ENV{'acc.res.'.$ENV{'request.course.id'}.'.'.$uripath}=~
-	   /\&$urifile\:(\d+)\&/) {
-	   $uricond=$1;
-       } elsif (($fe{$uritype} eq 'emb') || ($fe{$uritype} eq 'img')) {
-	  my $refuri=$ENV{'HTTP_REFERER'};
-          $refuri=~s/^\/res//;
-          $refuri=~s/^\///;
-          @uriparts=split(/\//,$refuri);
-          $urifile=$uriparts[$#uriparts];
-          $#uriparts--;
-          $uripath=join('/',@uriparts);
-          if ($ENV{'acc.res.'.$ENV{'request.course.id'}.'.'.$uripath}=~
-	     /\&$urifile\:(\d+)\&/) {
-	     $uricond=$1;
-	  }
+    unless ($ENV{'request.course.id'}) {
+       return '1';
+    }
+
+#
+# Now user is definitely in a course
+#
+
+
+# Course preferences
+
+   if ($thisallowed=~/C/) {
+       my $rolecode=(split(/\./,$ENV{'request.role'}))[0];
+       if ($ENV{'course.'.$ENV{'request.course.id'}.'.'.$priv.'.roles.denied'}
+	   =~/\,$rolecode\,/) {
+           &log('Denied by role: '.$priv.' for '.$uri.' as '.$rolecode.' in '.
+                $ENV{'request.course.id'});
+           return '';
        }
+   }
 
-       if ($uricond>=0) {
+# Resource preferences
 
-# The resource is part of the course
-# If user had full access on course level, go ahead
+   if ($thisallowed=~/R/) {
+       my $rolecode=(split(/\./,$ENV{'request.role'}))[0];
+       my $filename=$perlvar{'lonDocRoot'}.'/res/'.$uri.'.meta';
+       if (-e $filename) {
+           my @content;
+           {
+	     my $fh=Apache::File->new($filename);
+             @content=<$fh>;
+	   }
+           if (join('',@content)=~
+                    /\<roledeny[^\>]*\>[^\<]*$rolecode[^\<]*\<\/roledeny\>/) {
+	       &log('Denied by role: '.$priv.' for '.$uri.' as '.$rolecode);
+           return '';
 
-           if ($thisallowed=~/F/) {
-	       return 'F';
            }
+       }
+   }
 
 # Restricted by state?
 
-           if ($thisallowed=~/X/) {
-	      if (&condval($uricond)>1) {
-	         return '2';
-              } else {
-                 return '';
-              }
-	   }
-       }
-    }
-    return $thisallowed;
+   if ($thisallowed=~/X/) {
+      if (&condval($statecond)) {
+	 return '2';
+      } else {
+         return '';
+      }
+   }
+
+   return 'F';
 }
 
 # ---------------------------------------------------------- Refresh State Info
@@ -940,11 +1104,28 @@ sub dirlist {
 
 # -------------------------------------------------------- Value of a Condition
 
+sub directcondval {
+    my $number=shift;
+    if ($ENV{'user.state.'.$ENV{'request.course.id'}}) {
+       return substr($ENV{'user.state.'.$ENV{'request.course.id'}},$number,1);
+    } else {
+       return 2;
+    }
+}
+
 sub condval {
     my $condidx=shift;
     my $result=0;
+    my $allpathcond='';
+    map {
+       if (defined($ENV{'acc.cond.'.$ENV{'request.course.id'}.'.'.$_})) {
+	   $allpathcond.=
+               '('.$ENV{'acc.cond.'.$ENV{'request.course.id'}.'.'.$_}.')|';
+       }
+    } split(/\|/,$condidx);
+    $allpathcond=~s/\|$//;
     if ($ENV{'request.course.id'}) {
-       if (defined($ENV{'acc.cond.'.$ENV{'request.course.id'}.'.'.$condidx})) {
+       if ($allpathcond) {
           my $operand='|';
 	  my @stack;
           map {
@@ -960,16 +1141,14 @@ sub condval {
               } elsif (($_ eq '&') || ($_ eq '|')) {
                   $operand=$_;
               } else {
-                  my $new=
-                    substr($ENV{'user.state.'.$ENV{'request.course.id'}},$_,1);
+                  my $new=directcondval($_);
                   if ($operand eq '&') {
                      $result=$result>$new?$new:$result;
                   } else {
                      $result=$result>$new?$result:$new;
                   }                  
               }
-          } ($ENV{'acc.cond.'.$ENV{'request.course.id'}.'.'.$condidx}=~
-             /(\d+|\(|\)|\&|\|)/g);
+          } ($allpathcond=~/(\d+|\(|\)|\&|\|)/g);
        }
     }
     return $result;
@@ -978,20 +1157,84 @@ sub condval {
 # --------------------------------------------------------- Value of a Variable
 
 sub varval {
-    my ($realm,$space,@components)=split(/\./,shift);
-    my $value='';
+    my $varname=shift;
+    my ($realm,$space,$qualifier,@therest)=split(/\./,$varname);
+    my $rest;
+    if ($therest[0]) {
+       $rest=join('.',@therest);
+    } else {
+       $rest='';
+    }
     if ($realm eq 'user') {
-	if ($space=~/^resource/) {
-	    $space=~s/^resource\[//;
-            $space=~s/\]$//;
-
+# --------------------------------------------------------------- user.resource
+	if ($space eq 'resource') {
+# ----------------------------------------------------------------- user.access
+        } elsif ($space eq 'access') {
+            return &allowed($qualifier,$rest);
+# ------------------------------------------ user.preferences, user.environment
+        } elsif (($space eq 'preferences') || ($space eq 'environment')) {
+            return $ENV{join('.',('environment',$qualifier,$rest))};
+# ----------------------------------------------------------------- user.course
+        } elsif ($space eq 'course') {
+            return $ENV{join('.',('request.course',$qualifier))};
+# ------------------------------------------------------------------- user.role
+        } elsif ($space eq 'role') {
+            my ($role,$where)=split(/\./,$ENV{'request.role'});
+            if ($qualifier eq 'value') {
+		return $role;
+            } elsif ($qualifier eq 'extent') {
+                return $where;
+            }
+# ----------------------------------------------------------------- user.domain
+        } elsif ($space eq 'domain') {
+            return $ENV{'user.domain'};
+# ------------------------------------------------------------------- user.name
+        } elsif ($space eq 'name') {
+            return $ENV{'user.name'};
+# ---------------------------------------------------- Any other user namespace
         } else {
+            my $item=($rest)?$qualifier.'.'.$rest:$qualifier;
+            my %reply=&get($space,$item);
+            return $reply{$item};
+        }
+    } elsif ($realm eq 'request') {
+# ------------------------------------------------------------- request.browser
+        if ($space eq 'browser') {
+	    return $ENV{'browser.'.$qualifier};
+        } elsif ($space eq 'filename') {
+            return $ENV{'request.filename'};
         }
     } elsif ($realm eq 'course') {
-    } elsif ($realm eq 'session') {
+# ---------------------------------------------------------- course.description
+        if ($space eq 'description') {
+            my %reply=&coursedescription($ENV{'request.course.id'});
+            return $reply{'description'};
+# ------------------------------------------------------------------- course.id
+        } elsif ($space eq 'id') {
+            return $ENV{'request.course.id'};
+# -------------------------------------------------- Any other course namespace
+        } else {
+	    my ($cdom,$cnam)=split(/\_/,$ENV{'request.course.id'});
+	    my $chome=&homeserver($cnam,$cdom);
+            my $item=join('.',($qualifier,$rest));
+            return &unescape
+                   (&reply('get:'.$cdom.':'.$cnam.':'.&escape($space).':'.
+			   &escape($item),$chome));
+        }
+    } elsif ($realm eq 'userdata') {
+        my $uhome=&homeserver($qualifier,$space);
+# ----------------------------------------------- userdata.domain.name.resource
+# ---------------------------------------------------- Any other user namespace
+    } elsif ($realm eq 'environment') {
+# ----------------------------------------------------------------- environment
+        return $ENV{join('.',($space,$qualifier,$rest))};
     } elsif ($realm eq 'system') {
+# ----------------------------------------------------------------- system.time
+	if ($space eq 'time') {
+	    return time;
+        }
     }
-    return $value;
+    return '';
 }
 
 # ------------------------------------------------- Update symbolic store links
@@ -1017,11 +1260,15 @@ sub symblist {
 # ------------------------------------------------------ Return symb list entry
 
 sub symbread {
-    my $thisfn=declutter(shift);
+    my $thisfn=shift;
+    unless ($thisfn) {
+	$thisfn=$ENV{'request.filename'};
+    }
+    $thisfn=declutter($thisfn);
     my %hash;
     my %bighash;
     my $syval='';
-    if (($ENV{'request.course.fn'}) && ($ENV{'request.filename'})) {
+    if (($ENV{'request.course.fn'}) && ($thisfn)) {
         if (tie(%hash,'GDBM_File',$ENV{'request.course.fn'}.'_symb.db',
                       &GDBM_READER,0640)) {
 	    $syval=$hash{$thisfn};
@@ -1031,6 +1278,7 @@ sub symbread {
         if ($syval) {
            unless ($syval=~/\_\d+$/) {
 	       unless ($ENV{'form.request.prefix'}=~/\.(\d+)\_$/) {
+                  &appenv('request.ambiguous' => $thisfn);
                   return '';
                }    
                $syval.=$1;
@@ -1070,6 +1318,7 @@ sub symbread {
         }
         if ($syval) { return $syval.'___'.$thisfn; }
     }
+    &appenv('request.ambiguous' => $thisfn);
     return '';
 }
 
@@ -1089,7 +1338,7 @@ sub numval {
 
 sub rndseed {
     my $symb;
-    unless ($symb=&symbread($ENV{'request.filename'})) { return ''; }
+    unless ($symb=&symbread()) { return time; }
     my $symbchck=unpack("%32C*",$symb);
     my $symbseed=numval($symb)%$symbchck;
     my $namechck=unpack("%32C*",$ENV{'user.name'});
@@ -1126,11 +1375,21 @@ sub filelocation {
     $location = '/home/httpd/html/res'.$file;
   }
   $location=~s://+:/:g; # remove duplicate /
-  while ($location=~m:/../:) {$location=~ s:/[^/]+/\.\./:/:g;} #remove dir/..
-
+  while ($location=~m:/\.\./:) {$location=~ s:/[^/]+/\.\./:/:g;} #remove dir/..
   return $location;
 }
 
+sub hreflocation {
+    my ($dir,$file)=@_;
+    unless (($_=~/^http:\/\//i) || ($_=~/^\//)) {
+       my $finalpath=filelocation($dir,$file);
+       $finalpath=~s/^\/home\/httpd\/html//;
+       return $finalpath;
+    } else {
+       return $file;
+    }
+}
+
 # ------------------------------------------------------------- Declutters URLs
 
 sub declutter {