--- loncom/lonnet/perl/lonnet.pm	2000/09/29 14:36:30	1.33
+++ loncom/lonnet/perl/lonnet.pm	2000/10/05 19:27:23	1.36
@@ -33,6 +33,7 @@
 # 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
 # condval(index)     : value of condition index based on state
@@ -40,6 +41,10 @@
 # refreshstate()     : refresh the state information string
 # symblist(map,hash) : Updates symbolic storage links
 # 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
 #
 # 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,
@@ -51,7 +56,10 @@
 # 06/26 Ben Tyszka
 # 06/30,07/15,07/17,07/18,07/20,07/21,07/22,07/25 Gerd Kortemeyer
 # 08/14 Ben Tyszka
-# 08/22,08/28,08/31,09/01,09/02,09/04,09/05,09/25,09/28 Gerd Kortemeyer
+# 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
+
 
 package Apache::lonnet;
 
@@ -196,6 +204,15 @@ sub critical {
 
 sub appenv {
     my %newenv=@_;
+    map {
+	if (($newenv{$_}=~/^user\.role/) || ($newenv{$_}=~/^user\.priv/)) {
+            &logthis("<font color=blue>WARNING: ".
+                "Attempt to modify environment ".$_." to ".$newenv{$_});
+	    delete($newenv{$_});
+        } else {
+            $ENV{$_}=$newenv{$_};
+        }
+    } keys %newenv;
     my @oldenv;
     {
      my $fh;
@@ -445,6 +462,39 @@ sub restore {
     return %returnhash;
 }
 
+# ---------------------------------------------------------- Course Description
+
+sub coursedescription {
+    my $courseid=shift;
+    $courseid=~s/^\///;
+    my ($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 %returnhash=('home'   => $chome, 
+                           'domain' => $cdomain,
+                           'num'    => $cnum);
+           map {
+               my ($name,$value)=split(/\=/,$_);
+               $name=&unescape($name);
+               $value=&unescape($value);
+               $returnhash{$name}=$value;
+               if ($name eq 'description') {
+		   $cachehash{$courseid}=$value;
+               }
+           } split(/\&/,$rep);
+           $returnhash{'url'}='/res/'.declutter($returnhash{'url'});
+           $returnhash{'fn'}=$perlvar{'lonDaemons'}.'/tmp/'.
+	       $ENV{'user.name.'}.'_'.$cdomain.'_'.$cnum;
+	   put ('coursedescriptions',%cachehash);
+           return %returnhash;
+       }
+    }
+    return ();
+}
+
 # -------------------------------------------------------- Get user priviledges
 
 sub rolesinit {
@@ -1017,6 +1067,38 @@ sub rndseed {
                .$symbchck);
 }
 
+# ------------------------------------------------------------ Serves up a file
+# returns either the contents of the file or a -1
+sub getfile {
+  my $file=shift;
+  if (! -e $file ) {
+    &subscribe($file);
+    &repcopy($file);
+  }
+  if (! -e $file ) { return -1; };
+  my $fh=Apache::File->new($file);
+  my $a='';
+  while (<$fh>) { $a .=$_; }
+  return $a
+}
+
+sub filelocation {
+  my ($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;
+  } else {
+    $location = '/home/httpd/html/res'.$file;
+  }
+  $location=~s://+:/:g; # remove duplicate /
+  while ($location=~m:/../:) {$location=~ s:/[^/]+/\.\./:/:g;} #remove dir/..
+
+  return $location;
+}
+
 # ------------------------------------------------------------- Declutters URLs
 
 sub declutter {