--- loncom/lonnet/perl/lonnet.pm	2000/10/28 19:26:07	1.53
+++ loncom/lonnet/perl/lonnet.pm	2000/11/14 02:39:30	1.60
@@ -24,6 +24,7 @@
 # revokerole (udom,uname,url,role) : Revoke a role for url
 # revokecustomrole (udom,uname,url,rdom,rnam,rolename) : Revoke a custom role
 # appenv(hash)       : adds hash to session environment
+# delenv(varname)    : deletes all environment entries starting with varname
 # store(hash)        : stores hash permanently for this url
 # cstore(hash)       : critical store
 # restore            : returns hash for this url
@@ -41,7 +42,7 @@
 # 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
+# EXT(name)          : value of a variable
 # refreshstate()     : refresh the state information string
 # symblist(map,hash) : Updates symbolic storage links
 # symbread([filename]) : returns the data handle (filename optional)
@@ -66,8 +67,8 @@
 # 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
-# 10/06,10/09,10/10,10/11,10/14,10/20,10/23,10/25,10/26,10/27,10/28 
-# 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, 
+# 10/30,10/31,11/2,11/14 Gerd Kortemeyer
 
 package Apache::lonnet;
 
@@ -250,6 +251,35 @@ sub appenv {
     }
     return 'ok';
 }
+# ----------------------------------------------------- Delete from Environment
+
+sub delenv {
+    my $delthis=shift;
+    my %newenv=();
+    if (($delthis=~/user\.role/) || ($delthis=~/user\.priv/)) {
+        &logthis("<font color=blue>WARNING: ".
+                "Attempt to delete from environment ".$delthis);
+        return 'error';
+    }
+    my @oldenv;
+    {
+     my $fh;
+     unless ($fh=Apache::File->new("$ENV{'user.environment'}")) {
+	return 'error';
+     }
+     @oldenv=<$fh>;
+    }
+    {
+     my $fh;
+     unless ($fh=Apache::File->new(">$ENV{'user.environment'}")) {
+	return 'error';
+     }
+     map {
+	 unless ($_=~/^$delthis/) { print $fh $_; }
+     } @oldenv;
+    }
+    return 'ok';
+}
 
 # ------------------------------ Find server with least workload from spare.tab
 
@@ -499,6 +529,8 @@ sub coursedescription {
     if ($chome ne 'no_host') {
        my $rep=reply("dump:$cdomain:$cnum:environment",$chome);
        if ($rep ne 'con_lost') {
+           my $normalid=$courseid;
+           $normalid=~s/\//\_/g;
            my %envhash=();
            my %returnhash=('home'   => $chome, 
                            'domain' => $cdomain,
@@ -508,13 +540,15 @@ sub coursedescription {
                $name=&unescape($name);
                $value=&unescape($value);
                $returnhash{$name}=$value;
-               my $normalid=$courseid;
-               $normalid=~s/\//\_/g;
                $envhash{'course.'.$normalid.'.'.$name}=$value;
            } split(/\&/,$rep);
            $returnhash{'url'}='/res/'.declutter($returnhash{'url'});
            $returnhash{'fn'}=$perlvar{'lonDaemons'}.'/tmp/'.
 	       $ENV{'user.name'}.'_'.$cdomain.'_'.$cnum;
+           $envhash{'course.'.$normalid.'.last_cache'}=time;
+           $envhash{'course.'.$normalid.'.home'}=$chome;
+           $envhash{'course.'.$normalid.'.domain'}=$cdomain;
+           $envhash{'course.'.$normalid.'.num'}=$cnum;
            &appenv(%envhash);
            return %returnhash;
        }
@@ -717,9 +751,9 @@ sub allowed {
     my ($priv,$uri)=@_;
     $uri=&declutter($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';
     }
 
@@ -776,7 +810,7 @@ sub allowed {
        my $pathname=$uri;
        $pathname=~s/\/$filename$//;
        if ($ENV{'acc.res.'.$ENV{'request.course.id'}.'.'.$pathname}=~
-           /\&$filename\:(\d+)\&/) {
+           /\&$filename\:([\d\|]+)\&/) {
            $statecond=$1;
            if ($ENV{'user.priv.'.$ENV{'request.role'}.'./'.$courseprivid}
                =~/$priv\&([^\:]*)/) {
@@ -784,16 +818,19 @@ sub allowed {
                $checkreferer=0;
            }
        }
+
        if (($ENV{'HTTP_REFERER'}) && ($checkreferer)) {
-	  my $refuri=&declutter($ENV{'HTTP_REFERER'});
+	  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$//;
-          my @filenameparts=split(/\./,$filename);
+          my @filenameparts=split(/\./,$uri);
           if (&fileembstyle($filenameparts[$#filenameparts]) ne 'ssi') {
             if ($ENV{'acc.res.'.$ENV{'request.course.id'}.'.'.$pathname}=~
-              /\&$filename\:(\d+)\&/) {
+              /\&$filename\:([\d\|]+)\&/) {
               my $refstatecond=$1;
               if ($ENV{'user.priv.'.$ENV{'request.role'}.'./'.$courseprivid}
                   =~/$priv\&([^\:]*)/) {
@@ -830,37 +867,43 @@ sub allowed {
 #
 
 # 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\.([^\.]*)/) {
-	       my ($cdom,$cnum,$csec)=split(/\//,$1);
-               my %locks=();
-               map {
-                   my ($name,$value)=split(/\=/,$_);
-                   $locks{&unescape($name)}=&unescape($value);
-               } split(/\&/,&reply('get:'.$cdom.':'.$cnum.
-                 ':environment:'.&escape('priv.'.$priv.'.lock.sections').
-                             ':'.&escape('priv.'.$priv.'.lock.expire').
-                             ':'.&escape('res.'.$uri.'.lock.sections').
-			     ':'.&escape('res.'.$uri.'.lock.expire'),
-                  &homeserver($cnum,$cdom)));
-               if (($locks{'res.'.$uri.'.lock.sections'}=~/\,$csec\,/) ||
-                   ($locks{'res.'.$uri.'.lock.sections'} eq 'all')) {
-		   if ($locks{'res.'.$uri.'.lock.expire'}>time) {
-                       &log('Locked by res: '.$priv.' for '.$uri.' due to '.
+           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.'.$uri.'.lock.expire'}>time) {
+                       &log($ENV{'user.domain'},$ENV{'user.name'},
+                            $ENV{'user.host'},
+                            'Locked by res: '.$priv.' for '.$uri.' due to '.
                             $cdom.'/'.$cnum.'/'.$csec.' expire '.
-                            $locks{'priv.'.$priv.'.lock.expire'});
+                            $ENV{$prefix.'priv.'.$priv.'.lock.expire'});
 		       return '';
                    }
                }
-               if (($locks{'priv.'.$priv.'.lock.sections'}=~/\,$csec\,/) ||
-                   ($locks{'priv.'.$priv.'.lock.sections'} eq 'all')) {
-		   if ($locks{'priv.'.$priv.'.lock.expire'}>time) {
-                       &log('Locked by priv: '.$priv.' for '.$uri.' due to '.
+               if (($ENV{$prefix.'priv.'.$priv.'.lock.sections'}=~/\,$csec\,/)
+                || ($ENV{$prefix.'priv.'.$priv.'.lock.sections'} eq 'all')) {
+		   if ($ENV{'priv.'.$priv.'.lock.expire'}>time) {
+                       &log($ENV{'user.domain'},$ENV{'user.name'},
+                            $ENV{'user.host'},
+                            'Locked by priv: '.$priv.' for '.$uri.' due to '.
                             $cdom.'/'.$cnum.'/'.$csec.' expire '.
-                            $locks{'priv.'.$priv.'.lock.expire'});
+                            $ENV{$prefix.'priv.'.$priv.'.lock.expire'});
 		       return '';
                    }
                }
@@ -884,17 +927,35 @@ sub allowed {
 # Course preferences
 
    if ($thisallowed=~/C/) {
-#
-# Registered course preferences from environment
-#
+       my $rolecode=(split(/\./,$ENV{'request.role'}))[0];
+       if ($ENV{'course.'.$ENV{'request.course.id'}.'.'.$priv.'.roles.denied'}
+	   =~/\,$rolecode\,/) {
+           &log($ENV{'user.domain'},$ENV{'user.name'},$ENV{'user.host'},
+                'Denied by role: '.$priv.' for '.$uri.' as '.$rolecode.' in '.
+                $ENV{'request.course.id'});
+           return '';
+       }
    }
 
 # Resource preferences
 
    if ($thisallowed=~/R/) {
-#
-# Resource Metadata
-#
+       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($ENV{'user.domain'},$ENV{'user.name'},$ENV{'user.host'},
+                    'Denied by role: '.$priv.' for '.$uri.' as '.$rolecode);
+           return '';
+
+           }
+       }
    }
 
 # Restricted by state?
@@ -1094,8 +1155,16 @@ sub directcondval {
 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 {
@@ -1118,8 +1187,7 @@ sub condval {
                      $result=$result>$new?$result:$new;
                   }                  
               }
-          } ($ENV{'acc.cond.'.$ENV{'request.course.id'}.'.'.$condidx}=~
-             /(\d+|\(|\)|\&|\|)/g);
+          } ($allpathcond=~/(\d+|\(|\)|\&|\|)/g);
        }
     }
     return $result;
@@ -1127,7 +1195,7 @@ sub condval {
 
 # --------------------------------------------------------- Value of a Variable
 
-sub varval {
+sub EXT {
     my $varname=shift;
     my ($realm,$space,$qualifier,@therest)=split(/\./,$varname);
     my $rest;
@@ -1136,15 +1204,21 @@ sub varval {
     } else {
        $rest='';
     }
+    my $qualifierrest=$qualifier;
+    if ($rest) { $qualifierrest.='.'.$rest; }
+    my $spacequalifierrest=$space;
+    if ($qualifierrest) { $spacequalifierrest.='.'.$qualifierrest; }
     if ($realm eq 'user') {
 # --------------------------------------------------------------- user.resource
 	if ($space eq 'resource') {
+	    my %restored=&restore;
+            return $restored{$qualifierrest};
 # ----------------------------------------------------------------- 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))};
+            return $ENV{join('.',('environment',$qualifierrest))};
 # ----------------------------------------------------------------- user.course
         } elsif ($space eq 'course') {
             return $ENV{join('.',('request.course',$qualifier))};
@@ -1172,33 +1246,79 @@ sub varval {
 # ------------------------------------------------------------- request.browser
         if ($space eq 'browser') {
 	    return $ENV{'browser.'.$qualifier};
-        } elsif ($space eq 'filename') {
-            return $ENV{'request.filename'};
+# ------------------------------------------------------------ request.filename
+        } else {
+            return $ENV{'request.'.$spacequalifierrest};
         }
     } elsif ($realm eq 'course') {
 # ---------------------------------------------------------- course.description
-        if ($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));
+        my $section='';
+        if ($ENV{'request.course.sec'}) {
+	    $section='_'.$ENV{'request.course.sec'};
+        }
+        return $ENV{'course.'.$ENV{'request.course.id'}.$section.'.'.
+                              $spacequalifierrest};
+    } elsif ($realm eq 'resource') {
+      if ($ENV{'request.course.id'}) {
+# ----------------------------------------------------- Cascading lookup scheme
+       my $reslevel=
+	    $ENV{'request.course.id'}.'.'.&symbread().'.'.$spacequalifierrest;
+       my $seclevel=
+            $ENV{'request.course.id'}.'.'.
+		$ENV{'request.course.sec'}.'.'.$spacequalifierrest;
+       my $courselevel=
+            $ENV{'request.course.id'}.'.'.$spacequalifierrest;
+
+# ----------------------------------------------------------- first, check user
+       my %resourcedata=get('resourcedata',($reslevel,$seclevel,$courselevel));
+       if ($resourcedata{$reslevel}) { return $resourcedata{$reslevel}; }
+       if ($resourcedata{$seclevel}) { return $resourcedata{$seclevel}; }
+       if ($resourcedata{$courselevel}) { return $resourcedata{$courselevel}; }
+
+# -------------------------------------------------------- second, check course
+        my $section='';
+        if ($ENV{'request.course.sec'}) {
+	    $section='_'.$ENV{'request.course.sec'};
+        }
+        my $reply=&reply('get:'.
+              $ENV{'course.'.$ENV{'request.course.id'}.$section.'.domain'}.':'.
+              $ENV{'course.'.$ENV{'request.course.id'}.$section.'.num'}.
+              ':resourcedata:'.
+              escape($reslevel).':'.escape($seclevel).':'.escape($courselevel),
+		   $ENV{'course.'.$ENV{'request.course.id'}.$section.'.home'});
+        map {
+           my ($name,$value)=split(/\=/,$_);
+           $resourcedata{unescape($name)}=unescape($value);  
+        } split(/\&/,$reply);
+       if ($resourcedata{$reslevel}) { return $resourcedata{$reslevel}; }
+       if ($resourcedata{$seclevel}) { return $resourcedata{$seclevel}; }
+       if ($resourcedata{$courselevel}) { return $resourcedata{$courselevel}; }
+
+# ------------------------------------------------------ third, check map parms
+       
+       if ($ENV{'resource.parms.'.$reslevel}) {
+	   return $ENV{'resource.parms.'.$reslevel};
+       }
+     }
+     
+# --------------------------------------------- last, look in resource metadata
+	my $uri=&declutter($ENV{'request.filename'});
+        my $filename=$perlvar{'lonDocRoot'}.'/res/'.$ENV.'.meta';
+        if (-e $filename) {
+            my @content;
+            {
+             my $fh=Apache::File->new($filename);
+             @content=<$fh>;
+            }
+            if (join('',@content)=~
+                 /\<$space[^\>]*\>([^\<]*)\<\/$space\>/) {
+	        return $1;
+ 	    }
         }
-    } elsif ($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))};
+        return $ENV{$spacequalifierrest};
     } elsif ($realm eq 'system') {
 # ----------------------------------------------------------------- system.time
 	if ($space eq 'time') {
@@ -1338,12 +1458,17 @@ sub filelocation {
   my ($dir,$file) = @_;
   my $location;
   $file=~ s/^\s*(\S+)\s*$/$1/; ## strip off leading and trailing spaces
-  $file=~s/^$perlvar{'lonDocRoot'}//;
-  $file=~s:^/*res::;
-  if ( !( $file =~ m:^/:) ) {
-    $location = $dir. '/'.$file;
+  if ($file=~m:^/~:) { # is a contruction space reference
+    $location = $file;
+    $location =~ s:/~(.*?)/(.*):/home/$1/public_html/$2:;
   } else {
-    $location = '/home/httpd/html/res'.$file;
+    $file=~s/^$perlvar{'lonDocRoot'}//;
+    $file=~s:^/*res::;
+    if ( !( $file =~ m:^/:) ) {
+      $location = $dir. '/'.$file;
+    } else {
+      $location = '/home/httpd/html/res'.$file;
+    }
   }
   $location=~s://+:/:g; # remove duplicate /
   while ($location=~m:/\.\./:) {$location=~ s:/[^/]+/\.\./:/:g;} #remove dir/..