--- loncom/lonnet/perl/lonnet.pm	2010/10/01 14:26:07	1.1056.4.11
+++ loncom/lonnet/perl/lonnet.pm	2011/06/03 00:31:30	1.1056.4.26
@@ -1,7 +1,7 @@
 # The LearningOnline Network
 # TCP networking package
 #
-# $Id: lonnet.pm,v 1.1056.4.11 2010/10/01 14:26:07 raeburn Exp $
+# $Id: lonnet.pm,v 1.1056.4.26 2011/06/03 00:31:30 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -95,6 +95,7 @@ use Math::Random;
 use File::MMagic;
 use LONCAPA qw(:DEFAULT :match);
 use LONCAPA::Configuration;
+use File::Copy;
 
 my $readit;
 my $max_connection_retries = 10;     # Or some such value.
@@ -195,6 +196,29 @@ sub get_server_timezone {
     }
 }
 
+sub get_server_distarch {
+    my ($lonhost,$ignore_cache) = @_;
+    if (defined($lonhost)) {
+        if (!defined(&hostname($lonhost))) {
+            return;
+        }
+        my $cachetime = 12*3600;
+        if (!$ignore_cache) {
+            my ($distarch,$cached)=&is_cached_new('serverdistarch',$lonhost);
+            if (defined($cached)) {
+                return $distarch;
+            }
+        }
+        my $rep = &reply('serverdistarch',$lonhost);
+        unless ($rep eq 'unknown_command' || $rep eq 'no_such_host' ||
+                $rep eq 'con_lost' || $rep eq 'rejected' || $rep eq 'refused' ||
+                $rep eq '') {
+            return &do_cache_new('serverdistarch',$lonhost,$rep,$cachetime);
+        }
+    }
+    return;
+}
+
 sub get_server_loncaparev {
     my ($dom,$lonhost,$ignore_cache,$caller) = @_;
     if (defined($lonhost)) {
@@ -751,22 +775,22 @@ sub overloaderror {
 # ------------------------------ Find server with least workload from spare.tab
 
 sub spareserver {
-    my ($loadpercent,$userloadpercent,$want_server_name) = @_;
+    my ($loadpercent,$userloadpercent,$want_server_name,$udom) = @_;
     my $spare_server;
     if ($userloadpercent !~ /\d/) { $userloadpercent=0; }
     my $lowest_load=($loadpercent > $userloadpercent) ? $loadpercent 
                                                      :  $userloadpercent;
     my ($uint_dom,$remotesessions);
-    if ($env{'user.domain'}) {
-        my $uprimary_id = &Apache::lonnet::domain($env{'user.domain'},'primary');
+    if (($udom ne '') && (&domain($udom) ne '')) {
+        my $uprimary_id = &Apache::lonnet::domain($udom,'primary');
         $uint_dom = &Apache::lonnet::internet_dom($uprimary_id);
-        my %udomdefaults = &Apache::lonnet::get_domain_defaults($env{'user.domain'});
+        my %udomdefaults = &Apache::lonnet::get_domain_defaults($udom);
         $remotesessions = $udomdefaults{'remotesessions'};
     }
     foreach my $try_server (@{ $spareid{'primary'} }) {
         if ($uint_dom) {
-            next unless (&spare_can_host($env{'user.domain'},$uint_dom,
-                                         $remotesessions,$try_server));
+            next unless (&spare_can_host($udom,$uint_dom,$remotesessions,
+                                         $try_server));
         }
 	($spare_server, $lowest_load) =
 	    &compare_server_load($try_server, $spare_server, $lowest_load);
@@ -777,8 +801,8 @@ sub spareserver {
     if (!$found_server) {
 	foreach my $try_server (@{ $spareid{'default'} }) {
             if ($uint_dom) {
-                next unless (&spare_can_host($env{'user.domain'},$uint_dom,
-                                             $remotesessions,$try_server));
+                next unless (&spare_can_host($udom,$uint_dom,$remotesessions,
+                                             $try_server));
             }
 	    ($spare_server, $lowest_load) =
 		&compare_server_load($try_server, $spare_server, $lowest_load);
@@ -2199,6 +2223,8 @@ sub allowuploaded {
 #        path to file, source of file, instruction to parse file for objects,
 #        ref to hash for embedded objects,
 #        ref to hash for codebase of java objects.
+#        reference to scalar to accommodate mime type determined
+#          from File::MMagic if $parser = parse.
 #
 # output: url to file (if action was uploaddoc), 
 #         ok if successful, or diagnostic message otherwise (if action was propagate or copy)
@@ -2225,7 +2251,8 @@ sub allowuploaded {
 #
 
 sub process_coursefile {
-    my ($action,$docuname,$docudom,$file,$source,$parser,$allfiles,$codebase)=@_;
+    my ($action,$docuname,$docudom,$file,$source,$parser,$allfiles,$codebase,
+        $mimetype)=@_;
     my $fetchresult;
     my $home=&homeserver($docuname,$docudom);
     if ($action eq 'propagate') {
@@ -2253,13 +2280,16 @@ sub process_coursefile {
             close($fh);
             if ($parser eq 'parse') {
                 my $mm = new File::MMagic;
-                my $mime_type = $mm->checktype_filename($filepath.'/'.$fname);
-                if ($mime_type eq 'text/html') {
+                my $type = $mm->checktype_filename($filepath.'/'.$fname);
+                if ($type eq 'text/html') {
                     my $parse_result = &extract_embedded_items($filepath.'/'.$fname,$allfiles,$codebase);
                     unless ($parse_result eq 'ok') {
                         &logthis('Failed to parse '.$filepath.'/'.$fname.' for embedded media: '.$parse_result);
                     }
                 }
+                if (ref($mimetype)) {
+                    $$mimetype = $type;
+                }
             }
             $fetchresult= &reply('fetchuserfile:'.$docudom.'/'.$docuname.'/'.$file,
                                  $home);
@@ -2375,9 +2405,13 @@ sub resizeImage {
 
 # --------------- Take an uploaded file and put it into the userfiles directory
 # input: $formname - the contents of the file are in $env{"form.$formname"}
-#                    the desired filenam is in $env{"form.$formname.filename"}
-#        $coursedoc - if true up to the current course
-#                     if false
+#                    the desired filename is in $env{"form.$formname.filename"}
+#        $context - possible values: coursedoc, existingfile, overwrite, 
+#                                    canceloverwrite, or ''.
+#                   if 'coursedoc': upload to the current course
+#                   if 'existingfile': write file to tmp/overwrites directory
+#                   if 'canceloverwrite': delete file written to tmp/overwrites directory
+#                   $context is passed as argument to &finishuserfileupload 
 #        $subdir - directory in userfile to store the file into
 #        $parser - instruction to parse file for objects ($parser = parse)    
 #        $allfiles - reference to hash for embedded objects
@@ -2388,37 +2422,60 @@ sub resizeImage {
 #        $thumbheight - height (pixels) of thumbnail to make for uploaded image
 #        $resizewidth - width (pixels) to which to resize uploaded image
 #        $resizeheight - height (pixels) to which to resize uploaded image
+#        $mimetype - reference to scalar to accommodate mime type determined
+#                    from File::MMagic if $parser = parse.
 # 
 # output: url of file in userspace, or error: <message> 
 #             or /adm/notfound.html if failure to upload occurse
 
 sub userfileupload {
-    my ($formname,$coursedoc,$subdir,$parser,$allfiles,$codebase,$destuname,
-        $destudom,$thumbwidth,$thumbheight,$resizewidth,$resizeheight)=@_;
+    my ($formname,$context,$subdir,$parser,$allfiles,$codebase,$destuname,
+        $destudom,$thumbwidth,$thumbheight,$resizewidth,$resizeheight,$mimetype)=@_;
     if (!defined($subdir)) { $subdir='unknown'; }
     my $fname=$env{'form.'.$formname.'.filename'};
     $fname=&clean_filename($fname);
-# See if there is anything left
+    # See if there is anything left
     unless ($fname) { return 'error: no uploaded file'; }
-    chop($env{'form.'.$formname});
-    if (($formname eq 'screenshot') && ($subdir eq 'helprequests')) { #files uploaded to help request form are handled differently
+    # Files uploaded to help request form, or uploaded to "create course" page are handled differently
+    if ((($formname eq 'screenshot') && ($subdir eq 'helprequests')) ||
+        (($formname eq 'coursecreatorxml') && ($subdir eq 'batchupload')) ||
+         ($context eq 'existingfile') || ($context eq 'canceloverwrite')) {
         my $now = time;
-        my $filepath = 'tmp/helprequests/'.$now;
-        my @parts=split(/\//,$filepath);
-        my $fullpath = $perlvar{'lonDaemons'};
-        for (my $i=0;$i<@parts;$i++) {
-            $fullpath .= '/'.$parts[$i];
-            if ((-e $fullpath)!=1) {
-                mkdir($fullpath,0777);
+        my $filepath;
+        if (($formname eq 'screenshot') && ($subdir eq 'helprequests')) {
+             $filepath = 'tmp/helprequests/'.$now;
+        } elsif (($formname eq 'coursecreatorxml') && ($subdir eq 'batchupload')) {
+             $filepath = 'tmp/addcourse/'.$destudom.'/web/'.$env{'user.name'}.
+                         '_'.$env{'user.domain'}.'/pending';
+        } elsif (($context eq 'existingfile') || ($context eq 'canceloverwrite')) {
+            my ($docuname,$docudom);
+            if ($destudom) {
+                $docudom = $destudom;
+            } else {
+                $docudom = $env{'user.domain'};
+            }
+            if ($destuname) {
+                $docuname = $destuname;
+            } else {
+                $docuname = $env{'user.name'};
+            }
+            if (exists($env{'form.group'})) {
+                $docuname=$env{'course.'.$env{'request.course.id'}.'.num'};
+                $docudom=$env{'course.'.$env{'request.course.id'}.'.domain'};
+            }
+            $filepath = 'tmp/overwrites/'.$docudom.'/'.$docuname.'/'.$subdir;
+            if ($context eq 'canceloverwrite') {
+                my $tempfile =  $perlvar{'lonDaemons'}.'/'.$filepath.'/'.$fname;
+                if (-e  $tempfile) {
+                    my @info = stat($tempfile);
+                    if ($info[9] eq $env{'form.timestamp'}) {
+                        unlink($tempfile);
+                    }
+                }
+                return;
             }
         }
-        open(my $fh,'>'.$fullpath.'/'.$fname);
-        print $fh $env{'form.'.$formname};
-        close($fh);
-        return $fullpath.'/'.$fname;
-    } elsif (($formname eq 'coursecreatorxml') && ($subdir eq 'batchupload')) { #files uploaded to create course page are handled differently
-        my $filepath = 'tmp/addcourse/'.$destudom.'/web/'.$env{'user.name'}.
-                       '_'.$env{'user.domain'}.'/pending';
+        # Create the directory if not present
         my @parts=split(/\//,$filepath);
         my $fullpath = $perlvar{'lonDaemons'};
         for (my $i=0;$i<@parts;$i++) {
@@ -2430,27 +2487,31 @@ sub userfileupload {
         open(my $fh,'>'.$fullpath.'/'.$fname);
         print $fh $env{'form.'.$formname};
         close($fh);
-        return $fullpath.'/'.$fname;
+        if ($context eq 'existingfile') {
+            my @info = stat($fullpath.'/'.$fname);
+            return ($fullpath.'/'.$fname,$info[9]);
+        } else {
+            return $fullpath.'/'.$fname;
+        }
     }
     if ($subdir eq 'scantron') {
         $fname = 'scantron_orig_'.$fname;
-    } else {   
-# Create the directory if not present
+    } else {
         $fname="$subdir/$fname";
     }
-    if ($coursedoc) {
+    if ($context eq 'coursedoc') {
 	my $docuname=$env{'course.'.$env{'request.course.id'}.'.num'};
 	my $docudom=$env{'course.'.$env{'request.course.id'}.'.domain'};
         if ($env{'form.folder'} =~ m/^(default|supplemental)/) {
             return &finishuserfileupload($docuname,$docudom,
 					 $formname,$fname,$parser,$allfiles,
 					 $codebase,$thumbwidth,$thumbheight,
-                                         $resizewidth,$resizeheight);
+                                         $resizewidth,$resizeheight,$context,$mimetype);
         } else {
             $fname=$env{'form.folder'}.'/'.$fname;
             return &process_coursefile('uploaddoc',$docuname,$docudom,
 				       $fname,$formname,$parser,
-				       $allfiles,$codebase);
+				       $allfiles,$codebase,$mimetype);
         }
     } elsif (defined($destuname)) {
         my $docuname=$destuname;
@@ -2458,8 +2519,7 @@ sub userfileupload {
 	return &finishuserfileupload($docuname,$docudom,$formname,$fname,
 				     $parser,$allfiles,$codebase,
                                      $thumbwidth,$thumbheight,
-                                     $resizewidth,$resizeheight);
-        
+                                     $resizewidth,$resizeheight,$context,$mimetype);
     } else {
         my $docuname=$env{'user.name'};
         my $docudom=$env{'user.domain'};
@@ -2470,13 +2530,13 @@ sub userfileupload {
 	return &finishuserfileupload($docuname,$docudom,$formname,$fname,
 				     $parser,$allfiles,$codebase,
                                      $thumbwidth,$thumbheight,
-                                     $resizewidth,$resizeheight);
+                                     $resizewidth,$resizeheight,$context,$mimetype);
     }
 }
 
 sub finishuserfileupload {
     my ($docuname,$docudom,$formname,$fname,$parser,$allfiles,$codebase,
-        $thumbwidth,$thumbheight,$resizewidth,$resizeheight) = @_;
+        $thumbwidth,$thumbheight,$resizewidth,$resizeheight,$context,$mimetype) = @_;
     my $path=$docudom.'/'.$docuname.'/';
     my $filepath=$perlvar{'lonDocRoot'};
   
@@ -2502,7 +2562,23 @@ sub finishuserfileupload {
 	    print STDERR ('Failed to create '.$filepath.'/'.$file."\n");
 	    return '/adm/notfound.html';
 	}
-	if (!print FH ($env{'form.'.$formname})) {
+        if ($context eq 'overwrite') {
+            my $source =  $perlvar{'lonDaemons'}.'/tmp/overwrites/'.$docudom.'/'.$docuname.'/'.$fname;
+            my $target = $filepath.'/'.$file;
+            if (-e $source) {
+                my @info = stat($source);
+                if ($info[9] eq $env{'form.timestamp'}) {
+                    unless (&File::Copy::move($source,$target)) {
+                        &logthis('Failed to overwrite '.$filepath.'/'.$file);
+                        return "Moving from $source failed";
+                    }
+                } else {
+                    return "Temporary file: $source had unexpected date/time for last modification";
+                }
+            } else {
+                return "Temporary file: $source missing";
+            }
+	} elsif (!print FH ($env{'form.'.$formname})) {
 	    &logthis('Failed to write to '.$filepath.'/'.$file);
 	    print STDERR ('Failed to write to '.$filepath.'/'.$file."\n");
 	    return '/adm/notfound.html';
@@ -2518,8 +2594,8 @@ sub finishuserfileupload {
     }
     if ($parser eq 'parse') {
         my $mm = new File::MMagic;
-        my $mime_type = $mm->checktype_filename($filepath.'/'.$file);
-        if ($mime_type eq 'text/html') {
+        my $type = $mm->checktype_filename($filepath.'/'.$file);
+        if ($type eq 'text/html') {
             my $parse_result = &extract_embedded_items($filepath.'/'.$file,
                                                        $allfiles,$codebase);
             unless ($parse_result eq 'ok') {
@@ -2527,6 +2603,9 @@ sub finishuserfileupload {
 	   	         ' for embedded media: '.$parse_result); 
             }
         }
+        if (ref($mimetype)) {
+            $$mimetype = $type;
+        }
     }
     if (($thumbwidth =~ /^\d+$/) && ($thumbheight =~ /^\d+$/)) {
         my $input = $filepath.'/'.$file;
@@ -4396,22 +4475,22 @@ sub role_status {
 }
 
 sub check_adhoc_privs {
-    my ($cdom,$cnum,$then,$refresh,$now,$checkrole) = @_;
+    my ($cdom,$cnum,$then,$refresh,$now,$checkrole,$caller) = @_;
     my $cckey = 'user.role.'.$checkrole.'./'.$cdom.'/'.$cnum;
     if ($env{$cckey}) {
         my ($role,$where,$trolecode,$tstart,$tend,$tremark,$tstatus,$tpstart,$tpend);
         &role_status($cckey,$then,$refresh,$now,\$role,\$where,\$trolecode,\$tstatus,\$tstart,\$tend);
         unless (($tstatus eq 'is') || ($tstatus eq 'will_not')) {
-            &set_adhoc_privileges($cdom,$cnum,$checkrole);
+            &set_adhoc_privileges($cdom,$cnum,$checkrole,$caller);
         }
     } else {
-        &set_adhoc_privileges($cdom,$cnum,$checkrole);
+        &set_adhoc_privileges($cdom,$cnum,$checkrole,$caller);
     }
 }
 
 sub set_adhoc_privileges {
 # role can be cc or ca
-    my ($dcdom,$pickedcourse,$role) = @_;
+    my ($dcdom,$pickedcourse,$role,$caller) = @_;
     my $area = '/'.$dcdom.'/'.$pickedcourse;
     my $spec = $role.'.'.$area;
     my %userroles = &set_arearole($role,$area,'','',$env{'user.domain'},
@@ -4421,14 +4500,16 @@ sub set_adhoc_privileges {
     my ($author,$adv)= &set_userprivs(\%userroles,\%ccrole);
     &appenv(\%userroles,[$role,'cm']);
     &log($env{'user.domain'},$env{'user.name'},$env{'user.home'},"Role ".$role);
-    &appenv( {'request.role'        => $spec,
-              'request.role.domain' => $dcdom,
-              'request.course.sec'  => ''
-             }
-           );
-    my $tadv=0;
-    if (&allowed('adv') eq 'F') { $tadv=1; }
-    &appenv({'request.role.adv'    => $tadv});
+    unless ($caller eq 'constructaccess' && $env{'request.course.id'}) {
+        &appenv( {'request.role'        => $spec,
+                  'request.role.domain' => $dcdom,
+                  'request.course.sec'  => ''
+                 }
+               );
+        my $tadv=0;
+        if (&allowed('adv') eq 'F') { $tadv=1; }
+        &appenv({'request.role.adv'    => $tadv});
+    }
 }
 
 # --------------------------------------------------------------- get interface
@@ -5696,7 +5777,7 @@ sub allowed {
        my $unamedom=$env{'user.name'}.':'.$env{'user.domain'};
        if ($env{'course.'.$env{'request.course.id'}.'.'.$priv.'.roles.denied'}
 	   =~/\Q$rolecode\E/) {
-	   if ($priv ne 'pch') { 
+           if (($priv ne 'pch') && ($priv ne 'plc')) {
 	       &logthis($env{'user.domain'}.':'.$env{'user.name'}.':'.$env{'user.home'}.':'.
 			'Denied by role: '.$priv.' for '.$uri.' as '.$rolecode.' in '.
 			$env{'request.course.id'});
@@ -5706,7 +5787,7 @@ sub allowed {
 
        if ($env{'course.'.$env{'request.course.id'}.'.'.$priv.'.users.denied'}
 	   =~/\Q$unamedom\E/) {
-	   if ($priv ne 'pch') { 
+           if (($priv ne 'pch') && ($priv ne 'plc')) {
 	       &logthis($env{'user.domain'}.':'.$env{'user.name'}.':'.$env{'user.home'}.
 			'Denied by user: '.$priv.' for '.$uri.' as '.$unamedom.' in '.
 			$env{'request.course.id'});
@@ -5720,7 +5801,7 @@ sub allowed {
    if ($thisallowed=~/R/) {
        my $rolecode=(split(/\./,$env{'request.role'}))[0];
        if (&metadata($uri,'roledeny')=~/\Q$rolecode\E/) {
-	   if ($priv ne 'pch') { 
+           if (($priv ne 'pch') && ($priv ne 'plc')) {
 	       &logthis($env{'user.domain'}.':'.$env{'user.name'}.':'.$env{'user.home'}.':'.
 			'Denied by role: '.$priv.' for '.$uri.' as '.$rolecode);
 	   }
@@ -6073,9 +6154,9 @@ sub auto_get_sections {
 }
 
 sub auto_new_course {
-    my ($cnum,$cdom,$inst_course_id,$owner) = @_;
+    my ($cnum,$cdom,$inst_course_id,$owner,$coowners) = @_;
     my $homeserver = &homeserver($cnum,$cdom);
-    my $response=&unescape(&reply('autonewcourse:'.$inst_course_id.':'.$owner.':'.$cdom,$homeserver));
+    my $response=&unescape(&reply('autonewcourse:'.$inst_course_id.':'.&escape($owner).':'.$cdom.':'.&escape($coowners),$homeserver));
     return $response;
 }
 
@@ -7292,8 +7373,8 @@ sub store_userdata {
                     $namevalue.=&escape($key).'='.&freeze_escape($$storehash{$key}).'&';
                 }
                 $namevalue=~s/\&$//;
-                $result =  &reply("store:$env{'user.domain'}:$env{'user.name'}:".
-                                  "$namespace:$datakey:$namevalue",$uhome);
+                $result =  &reply("store:$udom:$uname:$namespace:$datakey:".
+                                  $namevalue,$uhome);
             }
         } else {
             $result = 'error: data to store was not a hash reference'; 
@@ -7346,10 +7427,10 @@ sub diskusage {
 }
 
 sub is_locked {
-    my ($file_name, $domain, $user) = @_;
+    my ($file_name, $domain, $user, $which) = @_;
     my @check;
     my $is_locked;
-    push @check, $file_name;
+    push(@check,$file_name);
     my %locked = &get('file_permissions',\@check,
 		      $env{'user.domain'},$env{'user.name'});
     my ($tmp)=keys(%locked);
@@ -7358,14 +7439,19 @@ sub is_locked {
     if (ref($locked{$file_name}) eq 'ARRAY') {
         $is_locked = 'false';
         foreach my $entry (@{$locked{$file_name}}) {
-           if (ref($entry) eq 'ARRAY') { 
+           if (ref($entry) eq 'ARRAY') {
                $is_locked = 'true';
-               last;
+               if (ref($which) eq 'ARRAY') {
+                   push(@{$which},$entry);
+               } else {
+                   last;
+               }
            }
        }
     } else {
         $is_locked = 'false';
     }
+    return $is_locked;
 }
 
 sub declutter_portfile {
@@ -8515,7 +8601,7 @@ sub metadata {
     if (($uri eq '') || 
 	(($uri =~ m|^/*adm/|) && 
 	     ($uri !~ m|^adm/includes|) && ($uri !~ m|/bulletinboard$|)) ||
-        ($uri =~ m|/$|) || ($uri =~ m|/.meta$|) ) {
+        ($uri =~ m|/$|) || ($uri =~ m|/.meta$|) || ($uri =~ m{^/*uploaded/.+\.sequence$})) {
 	return undef;
     }
     if (($uri =~ /^~/ || $uri =~ m{home/$match_username/public_html/}) 
@@ -8557,7 +8643,8 @@ sub metadata {
 		&Apache::lonnet::ssi_body($which,
 					  ('grade_target' => 'meta'));
 	    $cachetime = 1; # only want this cached in the child not long term
-	} elsif ($uri !~ m -^(editupload)/-) {
+	} elsif (($uri !~ m -^(editupload)/-) && 
+                 ($uri !~ m{^/*uploaded/$match_domain/$match_courseid/docs/})) {
 	    my $file=&filelocation('',&clutter($filename));
 	    #push(@{$metaentry{$uri.'.file'}},$file);
 	    $metastring=&getfile($file);
@@ -8905,7 +8992,8 @@ sub symbverify {
         }
         my $ids=$bighash{'ids_'.&clutter($thisurl)};
         unless ($ids) { 
-           $ids=$bighash{'ids_/'.$thisurl};
+           my $idkey = 'ids_'.($thisurl =~ m{^/}? '' : '/').$thisurl;
+           $ids=$bighash{$idkey};
         }
         if ($ids) {
 # ------------------------------------------------------------------- Has ID(s)
@@ -8918,7 +9006,8 @@ sub symbverify {
   &symbclean(&declutter($bighash{'map_id_'.$mapid}).'___'.$resid.'___'.$thisfn)
    eq $symb) { 
 		   if (($env{'request.role.adv'}) ||
-		       $bighash{'encrypted_'.$id} eq $env{'request.enc'}) {
+		       ($bighash{'encrypted_'.$id} eq $env{'request.enc'}) ||
+		       ($thisurl eq '/adm/navmaps')) {
 		       $okay=1; 
 		   }
 	       }
@@ -9997,13 +10086,19 @@ sub get_dns {
     my $loaded;
     my %name_to_host;
     my %internetdom;
+    my %LC_dns_serv;
 
     sub parse_hosts_tab {
 	my ($file) = @_;
 	foreach my $configline (@$file) {
 	    next if ($configline =~ /^(\#|\s*$ )/x);
-	    next if ($configline =~ /^\^/);
-	    chomp($configline);
+            chomp($configline);
+            if ($configline =~ /^\^/) {
+                if ($configline =~ /^\^([\w.\-]+)/) {
+                    $LC_dns_serv{$1} = 1;
+                }
+                next;
+            }
 	    my ($id,$domain,$role,$name,$protocol,$intdom)=split(/:/,$configline);
 	    $name=~s/\s//g;
 	    if ($id && $domain && $role && $name) {
@@ -11400,8 +11495,10 @@ userfileupload(): main rotine for puttin
            filename, and the contents of the file to create/modifed exist
            the filename is in $env{'form.'.$formname.'.filename'} and the
            contents of the file is located in $env{'form.'.$formname}
- coursedoc - if true, store the file in the course of the active role
-             of the current user
+ context - if coursedoc, store the file in the course of the active role
+             of the current user;
+           if 'existingfile': store in 'overwrites' in /home/httpd/perl/tmp
+           if 'canceloverwrite': delete file in tmp/overwrites directory
  subdir - required - subdirectory to put the file in under ../userfiles/
          if undefined, it will be placed in "unknown"
 
@@ -11423,16 +11520,29 @@ returns: the new clean filename
 
 =item *
 
-finishuserfileupload(): routine that creaes and sends the file to
+finishuserfileupload(): routine that creates and sends the file to
 userspace, probably shouldn't be called directly
 
   docuname: username or courseid of destination for the file
   docudom: domain of user/course of destination for the file
   formname: same as for userfileupload()
-  fname: filename (inculding subdirectories) for the file
+  fname: filename (including subdirectories) for the file
+  parser: if 'parse', will parse (html) file to extract references to objects, links etc.
+  allfiles: reference to hash used to store objects found by parser
+  codebase: reference to hash used for codebases of java objects found by parser
+  thumbwidth: width (pixels) of thumbnail to be created for uploaded image
+  thumbheight: height (pixels) of thumbnail to be created for uploaded image
+  resizewidth: width to be used to resize image using resizeImage from ImageMagick
+  resizeheight: height to be used to resize image using resizeImage from ImageMagick
+  context: if 'overwrite', will move the uploaded file from its temporary location to
+            userfiles to facilitate overwriting a previously uploaded file with same name.
+  mimetype: reference to scalar to accommodate mime type determined
+            from File::MMagic if $parser = parse.
 
  returns either the url of the uploaded file (/uploaded/....) if successful
- and /adm/notfound.html if unsuccessful
+ and /adm/notfound.html if unsuccessful (or an error message if context 
+ was 'overwrite').
+
 
 =item *