--- loncom/lonnet/perl/lonnet.pm	2000/09/30 17:25:04	1.34
+++ loncom/lonnet/perl/lonnet.pm	2000/10/07 10:09:53	1.39
@@ -28,7 +28,7 @@
 # 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 arry from namesp
+# del(namesp,array)  : deletes keys out of array from namesp
 # put(namesp,hash)   : stores hash in namesp
 # dump(namesp)       : dumps the complete namespace into a hash
 # ssi(url,hash)      : does a complete request cycle on url to localhost, posts
@@ -40,7 +40,12 @@
 # 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
 # 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,
@@ -53,6 +58,9 @@
 # 06/30,07/15,07/17,07/18,07/20,07/21,07/22,07/25 Gerd Kortemeyer
 # 08/14 Ben Tyszka
 # 08/22,08/28,08/31,09/01,09/02,09/04,09/05,09/25,09/28,09/30 Gerd Kortemeyer
+# 10/04 Gerd Kortemeyer
+# 10/04 Guy Albertelli
+# 10/06 Gerd Kortemeyer
 
 package Apache::lonnet;
 
@@ -197,6 +205,15 @@ 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;
@@ -412,7 +429,7 @@ sub log {
 sub store {
     my %storehash=@_;
     my $symb;
-    unless ($symb=escape(&symbread())) { return ''; }
+    unless ($symb=escape(&symbread($ENV{'request.filename'}))) { return ''; }
     my $namespace;
     unless ($namespace=$ENV{'request.course.id'}) { return ''; }
     my $namevalue='';
@@ -429,7 +446,7 @@ sub store {
 
 sub restore {
     my $symb;
-    unless ($symb=escape(&symbread())) { return ''; }
+    unless ($symb=escape(&symbread($ENV{'request.filename'}))) { return ''; }
     my $namespace;
     unless ($namespace=$ENV{'request.course.id'}) { return ''; }
     my $answer=reply(
@@ -471,7 +488,7 @@ sub coursedescription {
            } split(/\&/,$rep);
            $returnhash{'url'}='/res/'.declutter($returnhash{'url'});
            $returnhash{'fn'}=$perlvar{'lonDaemons'}.'/tmp/'.
-	       $ENV{'user.name.'}.'_'.$cdomain.'_'.$cnum;
+	       $ENV{'user.name'}.'_'.$cdomain.'_'.$cnum;
 	   put ('coursedescriptions',%cachehash);
            return %returnhash;
        }
@@ -1000,24 +1017,58 @@ sub symblist {
 # ------------------------------------------------------ Return symb list entry
 
 sub symbread {
+    my $thisfn=declutter(shift);
     my %hash;
-    my $syval;
+    my %bighash;
+    my $syval='';
     if (($ENV{'request.course.fn'}) && ($ENV{'request.filename'})) {
         if (tie(%hash,'GDBM_File',$ENV{'request.course.fn'}.'_symb.db',
                       &GDBM_READER,0640)) {
-            my $thisfn=declutter($ENV{'request.filename'});
 	    $syval=$hash{$thisfn};
-            if (untie(%hash)) {
-                unless ($syval=~/\_\d+$/) {
-		   unless ($ENV{'form.request.prefix'}=~/\.(\d+)\_$/) {
-                      return '';
-                   }    
-                   $syval.=$1;
-	        }
-                $syval.='___'.$thisfn;
-		return $syval;
-            }
+            untie(%hash);
         }
+# ---------------------------------------------------------- There was an entry
+        if ($syval) {
+           unless ($syval=~/\_\d+$/) {
+	       unless ($ENV{'form.request.prefix'}=~/\.(\d+)\_$/) {
+                  return '';
+               }    
+               $syval.=$1;
+	   }
+        } else {
+# ------------------------------------------------------- Was not in symb table
+           if (tie(%bighash,'GDBM_File',$ENV{'request.course.fn'}.'.db',
+                            &GDBM_READER,0640)) {
+# ---------------------------------------------- Get ID(s) for current resource
+              my $ids=$bighash{'ids_/res/'.$thisfn};
+              if ($ids) {
+# ------------------------------------------------------------------- Has ID(s)
+                 my @possibilities=split(/\,/,$ids);
+                 if ($#possibilities==0) {
+# ----------------------------------------------- There is only one possibility
+		     my ($mapid,$resid)=split(/\./,$ids);
+                     $syval=declutter($bighash{'map_id_'.$mapid}).'___'.$resid;
+                 } else {
+# ------------------------------------------ There is more than one possibility
+                     my $realpossible=0;
+                     map {
+			 my $file=$bighash{'src_'.$_};
+                         if (&allowed('bre',$file)) {
+         		    my ($mapid,$resid)=split(/\./,$_);
+                            if ($bighash{'map_type_'.$mapid} ne 'page') {
+				$realpossible++;
+                                $syval=declutter($bighash{'map_id_'.$mapid}).
+                                       '___'.$resid;
+                            }
+			 }
+                     } @possibilities;
+		     if ($realpossible!=1) { $syval=''; }
+                 }
+	      }
+              untie(%bighash)
+           } 
+        }
+        if ($syval) { return $syval.'___'.$thisfn; }
     }
     return '';
 }
@@ -1038,7 +1089,7 @@ sub numval {
 
 sub rndseed {
     my $symb;
-    unless ($symb=&symbread()) { return ''; }
+    unless ($symb=&symbread($ENV{'request.filename'})) { return ''; }
     my $symbchck=unpack("%32C*",$symb);
     my $symbseed=numval($symb)%$symbchck;
     my $namechck=unpack("%32C*",$ENV{'user.name'});
@@ -1051,6 +1102,35 @@ sub rndseed {
                .$symbchck);
 }
 
+# ------------------------------------------------------------ Serves up a file
+# returns either the contents of the file or a -1
+sub getfile {
+  my $file=shift;
+  &repcopy($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 {