X-Git-Url: http://matita.cs.unibo.it/gitweb/?a=blobdiff_plain;f=helm%2Fhttp_getter%2Fhttp_getter.pl.in;h=e9d1f4a3e04609137ad68b8db5658759be797f81;hb=5d7d6bd5090f3f82279bef0b93b4b361a5b1d751;hp=1c7359b6c885c6c0c79665b63b5fe5cff4e0185c;hpb=71cc512008eddc1c64b0388b7def903d1994eaa2;p=helm.git

diff --git a/helm/http_getter/http_getter.pl.in b/helm/http_getter/http_getter.pl.in
index 1c7359b6c..e9d1f4a3e 100755
--- a/helm/http_getter/http_getter.pl.in
+++ b/helm/http_getter/http_getter.pl.in
@@ -23,6 +23,15 @@
 # For details, see the HELM World-Wide-Web page,
 # http://cs.unibo.it/helm/.
 
+#use strict;
+
+my $VERSION = "@VERSION@";
+
+# various variables
+my ($HELM_LIB_PATH);
+my $cgi_dir = "@HELM_CGI_DIR@";
+my (%xml_map, %rdf_map, %xslt_map);
+
 # First of all, let's load HELM configuration
 use Env;
 my $HELM_LIB_DIR = $ENV{"HELM_LIB_DIR"};
@@ -34,21 +43,33 @@ if (defined ($HELM_LIB_DIR)) {
    $HELM_LIB_PATH = $DEFAULT_HELM_LIB_DIR."/configuration.pl";
 }
 
-# Let's override the configuration file
-$styles_dir = $ENV{"HELM_STYLE_DIR"} if (defined ($ENV{"HELM_STYLE_DIR"}));
-$dtd_dir = $ENV{"HELM_DTD_DIR"} if (defined ($ENV{"HELM_DTD_DIR"}));
+# next require defines: $helm_dir, $html_link, $dtd_dir, $uris_dbm, $indexname
+require $HELM_LIB_PATH;
 
-# <ZACK>: TODO temporary, move this setting to configuration file
-# set the cache mode, may be "gzipped" or "normal"
-my $cachemode = $ENV{'HTTP_GETTER_CACHE_MODE'} || 'gzipped';
+# TEMP: TODO put these vars in configuration file configuration.xml
+# <move_to_conf_file>
+my $cachemode = $ENV{'HTTP_GETTER_CACHE_MODE'} ||
+    'gzipped';
 if (($cachemode ne 'gzipped') and ($cachemode ne 'normal')) {
  die "Invalid HTTP_GETTER_CACHE_MODE environment variable, must be".
  "'normal' or 'gzipped'\n";
 }
-# </ZACK>
 
-# next require defines: $helm_dir, $html_link, $dtd_dir, $uris_dbm
-require $HELM_LIB_PATH;
+$helm_rdf_dir = $ENV{'HTTP_GETTER_RDF_DIR'} || $helm_rdf_dir;
+$rdf_dbm = $ENV{'HTTP_GETTER_RDF_DBM'} || $rdf_dbm;
+$xslt_dbm = $ENV{'HTTP_GETTER_XSLT_DBM'} || $xslt_dbm;
+$rdf_indexname = $ENV{'HTTP_GETTER_RDF_INDEXNAME'} || $rdf_indexname;
+$xslt_indexname = $ENV{'HTTP_GETTER_XSLT_INDEXNAME'} || $xslt_indexname;
+$servers_file = $ENV{'HTTP_GETTER_SERVERS_FILE'} || $servers_file;
+$uris_dbm = $ENV{'HTTP_GETTER_URIS_DBM'} || $uris_dbm;
+$dtdbaseurl = $ENV{'HTTP_GETTER_DTD_BASE_URL'} || $dtdbaseurl;
+$getterport = $ENV{'HTTP_GETTER_PORT'} || $getterport;
+  
+# </move_to_conf_file>
+
+# Let's override the configuration file
+$style_dir = $ENV{"HELM_STYLE_DIR"} if (defined ($ENV{"HELM_STYLE_DIR"}));
+$dtd_dir = $ENV{"HELM_DTD_DIR"} if (defined ($ENV{"HELM_DTD_DIR"}));
 
 use HTTP::Daemon;
 use HTTP::Status;
@@ -56,183 +77,173 @@ use HTTP::Request;
 use LWP::UserAgent;
 use DB_File;
 use Compress::Zlib;
+use CGI;
+use URI;
+use URI::Escape;
 
 #CSC: mancano i controlli sulle condizioni di errore di molte funzioni
 #CSC: ==> non e' robusto
 #CSC: altra roba da sistemare segnata con CSC
 
-my $d = new HTTP::Daemon LocalPort => 8081;
+my $d = new HTTP::Daemon LocalPort => $getterport
+ or die "Error: port $getterport not available.";
 my $myownurl = $d->url;
+
+# Let's patch the returned URL
 $myownurl =~ s/\/$//; # chop the final slash
-tie(%map, 'DB_File', $uris_dbm.".db", O_RDONLY, 0664);
+my $myownport = $myownurl;
+$myownport =~ s/http:\/\/(.*):(.*)/$2/;
+$myownurl  =~ s/http:\/\/(.*):(.*)/$1/;
+($myownurl) = gethostbyname($myownurl);
+$myownurl = "http://".$myownurl.":".$myownport;
+
+tie(%xml_map, 'DB_File', $uris_dbm, O_RDWR, 0664); # open dbs
+tie(%rdf_map, 'DB_File', $rdf_dbm, O_RDWR, 0664);
+tie(%xslt_map, 'DB_File', $xslt_dbm, O_RDWR, 0664);
+
+print "\n";
+print "HTTP Getter $VERSION\n"; # print hello information
 print "Please contact me at: <URL:", $myownurl."/", ">\n";
+print "\n";
+print "servers_file: $servers_file\n";
 print "helm_dir: $helm_dir\n";
-print "styles_dir: $styles_dir\n";
+print "helm_rdf_dir: $helm_rdf_dir\n";
+print "style_dir: $style_dir\n";
 print "dtd_dir: $dtd_dir\n";
-print "urls_of_uris.db: $uris_dbm.db\n";
+print "urls_of_uris db: $uris_dbm\n";
+print "rdf db: $rdf_dbm\n";
+print "xslt db: $xslt_dbm\n";
 print "cache mode: $cachemode\n";
+print "indexname: $indexname\n";
+print "rdf_indexname: $rdf_indexname\n";
+print "xslt_indexname: $xslt_indexname\n";
+print "dtdbaseurl: $dtdbaseurl\n";
+print "getterport: $getterport\n";
+print "\n";
 
 $SIG{CHLD} = "IGNORE"; # do not accumulate defunct processes
 $SIG{USR1} = \&update; # sent by the child to make the parent update
+
 while (my $c = $d->accept) {
  if (fork() == 0) {
     while (my $r = $c->get_request) {
         #CSC: mancano i controlli di sicurezza
         
-        my $inputuri = $r->url; 
-        $inputuri =~ s/^[^?]*\?uri=(.*)/$1/;
-        print "\nRequest: ".$r->url."\n\n";
         my $http_method = $r->method;
         my $http_path = $r->url->path;
+        my $http_query = uri_unescape($r->url->query);
+        my $cgi = new CGI("$http_query");
+        my $inputuri = $cgi->param('uri');
+        print "\nRequest: ".$r->url."\n\n";
 
-        if ($http_method eq 'GET' and $http_path eq "/getciconly") {
-            # finds the uri, url and filename
-            my $cicuri = $inputuri;
-
-            my $cicfilename = $cicuri;
-            $cicfilename =~ s/cic:(.*)/$1/;
-            $cicfilename =~ s/theory:(.*)/$1/;
-
-            my $cicurl   = $map{$cicuri};
-            my $extension;
-            if ($cicurl =~ /\.xml$/) { # non gzipped file
-              $extension = ".xml";
-            } elsif ($cicurl =~ /\.xml\.gz$/) { # gzipped file
-              $extension = ".xml.gz";
-            } else { # error: unknown extension
-             die "unexpected extension in url: $cicurl, might be '.xml'".
-              "or '.xml.gz'";
-            }
-            $cicfilename = $helm_dir.$cicfilename.$extension;
-
-            if (!defined($cicurl)) {
-             print "\nNOT FOUND!!!!!\n";
-             $c->send_error(RC_NOT_FOUND)
-            } else {
-               print_request("cic",$cicuri,$cicurl,$cicfilename);
+        print "\nUnescaped query: ".$http_query."\n";
 
-               # Retrieves the file
-               my $ciccontent = download(0,"cic",$cicurl,$cicfilename);
+         # "getxml" works with rdf uris
+        if ($http_method eq 'GET' and $http_path eq "/getxml") {
+            # finds the uri, url and filename
 
-               # Answering the client
-               answer($c,$ciccontent);
+            my $answerformat = $cgi->param('format');
+            my $patch_dtd = $cgi->param('patch_dtd');
+            $answerformat = "" if (not defined($answerformat));
+            $patch_dtd = "yes" if (not defined($patch_dtd));
+            if (($answerformat ne "gz") and ($answerformat ne "normal")
+               and ($answerformat ne "")) {
+             die "Wrong output format: $answerformat, must be 'normal' ".
+                 "or 'gz'\n";
             }
-        } elsif ($http_method eq 'GET' and $http_path eq "/get") {
-            # finds the uris, urls and filenames
-            my $cicuri = $inputuri,
-               $typesuri = $inputuri,
-               $annuri = $inputuri;
-            my $annsuffix;
-            if ($inputuri =~ /\.types$/) {
-               $cicuri    =~ s/(.*)\.types$/$1/;
-               undef($annuri);
-            } elsif ($inputuri =~ /\.types\.ann$/) {
-               $cicuri    =~ s/(.*)\.types\.ann$/$1/;
-               $typesuri  =~ s/(.*)\.ann$/$1/;
-               $annsuffix = ".types.ann";
-            } elsif ($inputuri =~ /\.ann$/) {
-               $cicuri  =~ s/(.*)\.ann$/$1/;
-               undef($typesuri);
-               $annsuffix = ".ann";
-            } else {
-               undef($typesuri);
-               undef($annuri);
+            if (($patch_dtd ne "yes") and ($patch_dtd ne "no")
+               and ($patch_dtd ne "")) {
+             die "Wrong param, patch_dtd must be 'yes' or 'no'\n";
             }
 
-            my $cicfilename = $cicuri;
-            $cicfilename =~ s/cic:(.*)/$1/;
-            $cicfilename =~ s/theory:(.*)/$1/;
-            $cicfilename = $helm_dir.$cicfilename;
-
-            my $cicurl   = $map{$cicuri};
-            my $typesurl = $map{$typesuri} if (defined($typesuri));
-            my $annurl   = $map{$annuri}  if (defined($annuri));
-            my ($cicext, $typesext, $annext);
-            if ($cicurl =~ /\.xml$/) { # normal file
-             $cicext = ".xml";
-            } elsif ($cicurl =~ /\.xml\.gz$/) { # gzipped file
-             $cicext = ".xml.gz";
-            } else {
-             die "unexpected extension in url: $cicurl;".
-             "might be '.xml' or '.xml.gz'";
-            }
-            if (defined($typesuri)) { # extension selection for types file
-             if ($typesurl =~ /\.xml$/) { # normal file
-              $typesext = ".types.xml";
-             } elsif ($typesurl =~ /\.xml\.gz$/) { # gzipped file
-              $typesext = ".types.xml.gz";
-             } else {
-              die "unexpected extension in url: $typesurl;".
-              "might be '.xml' or '.xml.gz'";
-             }
-            }
-            if (defined($annuri)) { # extension selection for annotation file
-             if ($annurl =~ /\.xml$/) { # normal file
-              $annext = ".xml";
-             } elsif ($annurl =~ /\.xml\.gz$/) { # gzipped file
-              $annext = ".xml.gz";
-             } else {
-              die "unexpected extension in url: $annurl".
-              "might be '.xml' or '.xml.gz'";
-             }
+            my $filename = $inputuri;
+            my $prefix;
+            if (not isRdfUri($inputuri)) { # standad cic: or theory: uri
+             $filename =~ s/^cic:(.*)/$1/;
+             $filename =~ s/^theory:(.*)/$1/;
+            } else { # rdf uri
+             # The "helm:rdf/<<...>>//cic:" prefix is kept, but quoted
+             # (so that a "helm:rdf/<<...>>//cic:" dir is created
+             $prefix = $filename;
+             $filename =~ s/^(.*)\/\/cic:(.*)/$2/;
+             $filename =~ s/^(.*)\/\/theory:(.*)/$2/;
+             $prefix =~ s/\Q$filename\E//;
+             $prefix =~ s/_/__/g;
+             $prefix =~ s/\//_/g;
+             $filename = $prefix.$filename;
             }
-            my $typesfilename = $cicfilename.$typesext if $typesuri;
-            my $annfilename  = $cicfilename.$annsuffix.$annext if $annuri;
-            $cicfilename .= $cicext;
-
-            if (!defined($cicurl) ||
-               (!defined($typesurl) && $typesuri) ||
-               (!defined($annuri) && $annuri))
-            {
-             print "\nNOT FOUND!!!!!\n";
-             $c->send_error(RC_NOT_FOUND)
-            } else {
-               print_request("cic",$cicuri,$cicurl,$cicfilename);
-               print_request("types",$typesuri,$typesurl,$typesfilename)
-                if ($typesuri);
-               print_request("ann",$annuri,$annurl,$annfilename)
-                if ($annuri);
- 
-               # Retrieves the files
 
-               my $ciccontent = download(1,"cic",$cicurl,$cicfilename);
-               my $typescontent =
-                download(1,"types",$typesurl,$typesfilename) if ($typesuri);
-               my $anncontent =
-                download(1,"ann",$annurl,$annfilename) if ($annuri);
- 
-               # Merging the files together
- 
-               my $merged = <<EOT;
-<?xml version="1.0" encoding="UTF-8"?>
-<cicxml uri="$cicuri">
-$ciccontent
-$typescontent
-$anncontent
-</cicxml>
-EOT
-
-               # Answering the client
-               answer($c,$merged);
+            my $url = resolve ($inputuri); # resolve uri in url
+            if (not defined($url)) { # uri not found in uri2url map
+             die "NOT FOUND: uri \"$inputuri\" can't be resolved\n";
+             $c->send_error(RC_NOT_FOUND)
+            } else { # uri found and mapped to url
+              my $extension; # file extension
+              if ($url =~ /\.xml$/) { # non gzipped file
+                $extension = ".xml";
+              } elsif ($url =~ /\.xml\.gz$/) { # gzipped file
+                $extension = ".xml.gz";
+              } else { # error: unknown extension
+               die "unexpected extension in url: $url, might be '.xml'".
+                "or '.xml.gz'";
+              }
+
+              if (not isRdfUri ($inputuri)) { # save in uri std cache dir
+               $filename = $helm_dir.$filename.$extension;
+              } else { # save in rdf metadata cache dir
+               $filename = $helm_rdf_dir."/".$filename.$extension;
+              }
+
+              print_request($inputuri,$url,$filename);
+
+              # Retrieves the file
+              my $ciccontent = download($patch_dtd,$url,$filename,$answerformat);
+
+              if ($answerformat eq "normal") { # answer the client in text/xml
+               answer($c,$ciccontent,"text/xml","");
+              } else { # answer the client in text/xml, gzip encoding
+               answer($c,$ciccontent,"text/xml","x-gzip");
+              }
             }
-         } elsif ($http_method eq 'GET' and $http_path eq "/getdtd") {
+            
+                           # "/register" does not work with rdf uris
+        } elsif ($http_method eq 'GET' and $http_path eq "/register") {
+          my $inputurl = $cgi->param('url');
+          print "Register requested...\n";
+          $xml_map{$inputuri}=$inputurl;
+
+          # Now let's clean the cache
+          my $cicfilename = $inputuri;
+          $cicfilename =~ s/cic:(.*)/$1/;
+          $cicfilename =~ s/theory:(.*)/$1/;
+
+          print "Unlinking ".$helm_dir.$cicfilename.".xml[.gz]\n";
+          unlink ($helm_dir.$cicfilename.".xml");
+          unlink ($helm_dir.$cicfilename.".xml.gz");
+
+          kill(USR1,getppid()); # signal changes to parent
+          untie %xml_map;
+          print "done.\n";
+          html_nice_answer($c,"Register done");
+
+                                  # "/resolve" works with rdf uri
+        } elsif ($http_method eq 'GET' and $http_path eq "/resolve") {
+          #my $outputurl = $xml_map{$inputuri};
+          my $outputurl = resolve($inputuri);
+          $outputurl = "" if (not defined($outputurl));
+          $cont = "<?xml version=\"1.0\" ?>\n\n";
+          if ($outputurl eq "") {
+           $cont .= "<unresolved />\n";
+          } else {
+           $cont .= "<url value=\"$outputurl\" />\n";
+          }
+          answer($c,$cont,"text/xml","");
+
+        } elsif ($http_method eq 'GET' and $http_path eq "/getdtd") {
+
             my $filename = $inputuri;
             $filename = $dtd_dir."/".$filename;
             print "DTD: $inputuri ==> ($filename)\n";
-            if (stat($filename)) {
-               print "Using local copy\n";
-               open(FD, $filename) or die "Cannot open $filename\n";
-               $cont = "";
-               while(<FD>) { $cont .= $_; }
-               close(FD);
-               answer($c,$cont);
-            } else {
-               die "Could not find DTD!";
-            }
-         } elsif ($http_method eq 'GET' and $http_path eq "/getxslt") {
-            my $filename = $inputuri;
-            $filename = $styles_dir."/".$filename;
-            print "XSLT: $inputuri ==> ($filename)\n";
             if (stat($filename)) {
                print "Using local copy\n";
                open(FD, $filename) or die "Cannot open $filename\n";
@@ -240,37 +251,171 @@ EOT
                while(<FD>) {
                 # Vary bad heuristic for substituion of absolute URLs
                 # for relative ones
-                s/xsl:import\s+href="/xsl:import href="$myownurl\/getxslt?uri=/g ;
-                s/xsl:include\s+href="/xsl:include href="$myownurl\/getxslt?uri=/g ;
-                $cont .= $_;
-               }
+		s/ENTITY (.*) SYSTEM\s+"/ENTITY $1 SYSTEM "$myownurl\/getdtd?uri=/g;
+	        $cont .= $_;
+	       }
                close(FD);
-               answer($c,$cont);
+               answer($c,$cont,"text/xml","");
             } else {
-               die "Could not find XSLT!";
+               die "Could not find DTD!";
             }
-        } elsif ($http_method eq 'GET' and $http_path eq "/conf") {
-            my $quoted_html_link = $html_link;
-            $quoted_html_link =~ s/&/&amp;/g;
-            $quoted_html_link =~ s/</&lt;/g;
-            $quoted_html_link =~ s/>/&gt;/g;
-            $quoted_html_link =~ s/'/&apos;/g;
-            $quoted_html_link =~ s/"/&quot;/g;
-            print "\nConfiguration requested, returned #$quoted_html_link#\n";
-	    $cont = "<?xml version=\"1.0\"?><html_link>$quoted_html_link</html_link>";
-            answer($c,$cont);
+
+        } elsif ($http_method eq 'GET' and $http_path eq "/getxslt") {
+
+          $url = $xslt_map{$inputuri};
+          print "Downloading XSLT ...\n";
+          helm_wget($tmp_dir, $url);
+          print "XSLT downloaded!\n";
+          $inputuri =~ s/.*\///;
+          my $filename = $tmp_dir . "/" . $inputuri;
+          my $cont;
+          die "Could not find XSLT!\n" unless stat($filename);
+          open(FD, $filename) or die "Can't open xslt local copy: '$filename'\n";
+          while(<FD>) {
+            s/xsl:import\s+href="/xsl:import href="$myownurl\/getxslt?uri=/g;
+            s/xsl:include\s+href="/xsl:include href="$myownurl\/getxslt?uri=/g;
+            $cont .= $_;
+          }
+          close(FD);
+          answer($c, $cont, "text/xml", "");
+          unlink $filename or
+            print "Can't unlink XSLT temp file '$filename'";
+
+# <old_version>
+#             my $filename = $inputuri;
+#             $filename = $style_dir."/".$filename;
+#             print "XSLT: $inputuri ==> ($filename)\n";
+#             if (stat($filename)) {
+#                print "Using local copy\n";
+#                open(FD, $filename) or die "Cannot open $filename\n";
+#                $cont = "";
+#                while(<FD>) {
+#                 # Vary bad heuristic for substituion of absolute URLs
+#                 # for relative ones
+#                 s/xsl:import\s+href="/xsl:import href="$myownurl\/getxslt?uri=/g ;
+#                 s/xsl:include\s+href="/xsl:include href="$myownurl\/getxslt?uri=/g ;
+#                 $cont .= $_;
+#                }
+#                close(FD);
+#                answer($c,$cont,"text/xml","");
+#             } else {
+#                die "Could not find XSLT!";
+#             }
+# </old_version>
+
+                                    # "/update" works with rdf uri
         } elsif ($http_method eq 'GET' and $http_path eq "/update") {
-           print "Update requested...";
-           update();
-           kill(USR1,getppid());
+            # rebuild urls_of_uris db and rdf uris db
+           print "Update requested...\n";
+           update_dbs();
+           kill(USR1,getppid()); # signal changes to parent
            print " done\n";
-           answer($c,"<html><body><h1>Update done</h1></body></html>");
-        } else {
-            print "\nINVALID REQUEST!!!!!\n";
+           html_nice_answer($c,"Update done");
+
+                                 # "/getalluris" does not work with rdf uris
+        } elsif ($http_method eq 'GET' and $http_path eq "/getalluris") {
+            # send back all the keys in xml
+            print "BASEURI $baseuri, FORMAT $outype\n";
+            $cont = getalluris();
+            answer($c,$cont,"text/xml","");
+
+                                 # "/getallrdfuris"
+        } elsif ($http_method eq 'GET' and $http_path eq "/getallrdfuris") {
+            # send back all the keys in xml
+            my $class = $cgi->param('class');
+            print "BASEURI $baseuri, FORMAT $outype, CLASS $class\n";
+            $cont = getallrdfuris($class);
+            answer($c,$cont,"text/xml","");
+
+        } elsif ($http_method eq 'GET' and $http_path eq "/ls") {
+            # send back keys that begin with a given uri
+           my ($uritype,$uripattern,$uriprefix);
+           my $baseuri = $cgi->param('baseuri');
+           chop $baseuri if ($baseuri =~ /.*\/$/); # remove trailing "/"
+                         # output type, might be 'txt' or 'xml':
+           my $outype = $cgi->param('format');
+           $uripattern = $baseuri;
+           $uripattern =~ s/^.*:(.*)/$1/;
+           if ($baseuri =~ /^cic:/) {
+            $uritype = "cic";
+           } elsif ($baseuri =~ /^theory:/) {
+            $uritype = "theory";
+           } else {
+            $uritype = "invalid";
+           }
+           if ($uritype ne "invalid") { # uri is valid
+            if (($outype ne 'txt') and ($outype ne 'xml')) { # invalid out type
+             print "Invalid output type specified: $outype\n";
+             html_nice_answer($c,"Invalid output type, must be ".
+              "'txt' or 'xml'");
+            } else { # valid output
+             print "BASEURI $baseuri, FORMAT $outype\n";
+             $cont = finduris($uritype,$uripattern,$outype);
+             if ($outype eq 'txt') {
+              answer($c,$cont,"text/plain","");
+             } elsif ($outype eq 'xml') {
+              answer($c,$cont,"text/xml","");
+             } else {
+              die "Internal error, exiting!";
+             }
+            }
+           } else { # invalid uri
+            print "Invalid uri: $baseuri, may begin with 'cic:', ".
+             "'theory:' or '*:'\n";
+            html_nice_answer($c,"Invalid uri , must begin with ".
+             "'cic:' or 'theory:'");
+           }
+
+        } elsif ($http_method eq 'GET' and $http_path eq "/help") {
+          # help request
+           print "Help requested!\n";
+           html_nice_answer($c,"HTTP Getter Version: $VERSION");
+
+        } elsif ($http_method eq 'GET' and $http_path eq "/getempty") {
+          # return an empty, but valid, xml document
+          my $emptyxml = <<EOXML;
+<?xml version="1.0"?>
+<!DOCTYPE empty [
+  <!ELEMENT empty EMPTY>
+]>
+<empty />
+EOXML
+          answer($c, $emptyxml, "", "");
+
+        } elsif ($http_method eq 'GET' and $http_path =~ /\.cgi$/) {
+          # cgi handling
+           print "CGI requested!\n";
+           if ($http_path !~ /^\/[^\/]*\.cgi$/) {
+            html_nice_answer($c,"Invalid CGI name: $http_path, ".
+            "you can't request CGI that contain a slash in the name\n");
+           } elsif (stat "$cgi_dir"."$http_path") {
+            if (not -x "$cgi_dir/$http_path") {
+             html_nice_answer($c,"CGI $http_path found but not ".
+              "executable\n");
+            } else { # exec CGI and anser back its output
+             my %old_ENV = %ENV;
+             %ENV = ();
+             $ENV{'QUERY_STRING'} = $http_query;
+             my $cgi_output = `$cgi_dir/$http_path`;
+             answer($c,$cgi_output,"","");
+             %ENV = %old_ENV;
+            }
+           } else {
+            html_nice_answer($c,"CGI '$http_path' not found ".
+             "in CGI dir '$cgi_dir'");
+           }
+
+        } else { # unsupported request
+            print "\n";
+            print "INVALID REQUEST!!!!!\n";
+            print "(PATH: ",$http_path,", ";
+            print "QUERY: ",$http_query,")\n";
             $c->send_error(RC_FORBIDDEN)
         }
+
         print "\nRequest solved: ".$r->url."\n\n";
     }
+
     $c->close;
     undef($c);
     print "\nCONNECTION CLOSED\n\n";
@@ -280,6 +425,225 @@ EOT
 
 #================================
 
+sub isRdfUri { # return true if the uri is an rdf uri, false otherwise
+# typycal rdf uri:
+# helm:rdf/cic:www.cs.unibo.it/helm/rdf/foo_schema//cic:\
+#  /Coq/Init/Logic/True_rec.con.types
+#
+# the format is "helm:rdf/<metadata_tree>:<metadata_scheme>//<xml_file_uri>"
+#
+ my ($uri) = @_;
+ if ($uri =~ /^helm:rdf(.*):(.*)\/\/(.*)/) {
+  return 1;
+ } else {
+  return 0;
+ }
+}
+
+sub resolve { # resolve an uri in a url, work both with standard cic: or theory:
+              # uris and rdf uris
+ print "RESOLVE subroutine\n";
+ my ($uri) = @_;
+ print "GIVEN URI: \"$uri\"\n";
+ if (isRdfUri ($uri)) { # rdf uri, resolve using rdf db
+  print "IS A RDF URI\n";
+  print "I WILL RETURN '$rdf_map{$uri}'\n";
+  return ($rdf_map{$uri});
+ } else { # standard cic: or theory: uri, resolve using std uri db
+  print "IS NOT A RDF URI\n";
+  print "I WILL RETURN '$xml_map{$uri}'\n";
+  return ($xml_map{$uri});
+ }
+}
+
+sub getalluris { # get all the keys whose prefix is cic
+ my $content = "";
+ my ($uri);
+ my $debug=1; # for debug
+
+  $content .= '<?xml version="1.0" encoding="ISO-8859-1"?>' . "\n";
+  $content .= "<!DOCTYPE alluris SYSTEM ";
+  $content .= "\"$myownurl/getdtd?uri=alluris.dtd\">" . "\n\n";
+  $content .= "<alluris>\n";
+  foreach $uri (sort (keys(%xml_map))) { # select matching uris
+   if ($uri =~ /^cic:/ && not $uri =~ /.types$/) {
+    print "GETALLURI: $uri\n" if defined($debug);
+    $content .= "\t<uri value=\"$uri\"/>\n";
+   }
+  }
+  $content .= "</alluris>\n";
+ return $content;
+}
+
+sub getallrdfuris {
+ my $class = $_[0];
+ my $content = "";
+ my ($uri);
+ my $debug=1; # for debug
+
+  $content .= '<?xml version="1.0" encoding="ISO-8859-1"?>' . "\n";
+  $content .= "<!DOCTYPE allrdfuris SYSTEM ";
+  $content .= "\"$myownurl/getdtd?uri=alluris.dtd\">" . "\n\n";
+  $content .= "<allrdfuris>\n";
+  foreach $uri (sort (keys(%rdf_map))) {
+   if ($class eq "forward" &&
+        $uri =~ /^helm:rdf:www.cs.unibo.it\/helm\/rdf\/forward/
+       ||
+        $class eq "backward" &&
+         $uri =~ /^helm:rdf:www.cs.unibo.it\/helm\/rdf\/backward/) {
+      print "GETALLRDFURI: $uri\n" if defined($debug);
+      $content .= "\t<uri value=\"$uri\"/>\n";
+   }
+  }
+  $content .= "</allrdfuris>\n";
+ return $content;
+}
+
+sub finduris { # find uris for cic and theory trees generation
+ my ($uritype,$uripattern,$format) = @_;
+ my $content = "";
+ my ($uri,$localpart,$basepart,$dirname,$suffix,$flags,$key);
+ my (@itemz,@already_pushed_dir);
+ my (%objects,%dirs); # map uris to suffixes' flags
+ my $debug=1; # for debug
+
+ print "FINDURIS, uritype: $uritype, uripattern: $uripattern, ".
+  "format: $format\n\n" if defined($debug);
+ 
+ if (($uritype eq "cic") or ($uritype eq "theory")) {
+   # get info only of one type: cic or theory
+  foreach (keys(%xml_map)) { # select matching uris
+   $uri = $_;
+   if ($uri =~ /^$uritype:$uripattern(\/|$|\.)/) {
+    if ($uri =~ /^$uritype:$uripattern\//) { # directory match
+     $localpart = $uri;
+     $localpart =~ s/^$uritype:$uripattern\/(.*)/$1/;
+    } elsif ($uri =~ /^$uritype:$uripattern($|\.)/) { # file match
+     $localpart = $uri;
+     $localpart =~ s/^.*\/([^\/]*)/$1/;
+    } else {
+     die "Internal error, seems that requested match is none of ".
+      "directory match or file match";
+    }
+    print "LOCALPART: $localpart\n" if defined($debug);
+
+    if ($localpart =~ /^[^\/]*$/) { # no slash, an OBJECT
+     $basepart = $localpart;
+     $basepart =~ s/^([^.]*\.[^.]*)((\.body)|(\.types))?(\.ann)?/$1/;
+                                              # remove exts .types, .body,
+                                              # .types.ann or .body.ann
+     $flags = $objects{$basepart}; # get old flags
+     if ($localpart =~ /\.ann$/) {
+      $flags = add_flag("ann","YES",$flags);
+     } else {
+      $flags = add_flag("ann","NO",$flags);
+     }
+     if ($localpart =~ /\.types$/) {
+      $flags = add_flag("types","YES",$flags);
+     } elsif ($localpart =~ /\.types\.ann$/) {
+      $flags = add_flag("types","ANN",$flags);
+     } else {
+      $flags = add_flag("types","NO",$flags);
+     }
+     if ($localpart =~ /\.body$/) {
+      $flags = add_flag("body","YES",$flags);
+     } elsif ($localpart =~ /\.body\.ann$/) {
+      $flags = add_flag("body","ANN",$flags);
+     } else {
+      $flags = add_flag("body","NO",$flags);
+     }
+     $objects{$basepart} = $flags; # save new flags
+    } else { # exists at least one slash, a DIR
+     ($dirname) = split (/\//, $localpart);
+     $dirs{$dirname} = ""; # no flags requirement for dir
+    }
+   }
+  }
+ } else {
+  die "getter internal error: unsupported uritype: \"$uritype\"";
+ }
+                            # now generate OUTPUT:
+                            # output will be saved in $content
+ if ($format eq "txt") { # TXT output
+  foreach $key (sort(keys %dirs)) {
+   $content .= "dir, " . $key . "\n";
+  }
+  foreach $key (sort(keys %objects)) {
+   $content .= "object, $key, " . $objects{$key} . "\n";
+  }
+ } elsif ($format eq "xml") { # XML output
+  $content .= '<?xml version="1.0" encoding="ISO-8859-1"?>' . "\n";
+  $content .= "<!DOCTYPE ls SYSTEM ";
+  $content .= "\"$myownurl/getdtd?uri=ls.dtd\">" . "\n\n";
+  $content .= "<ls>\n";
+  foreach $key (sort(keys %dirs)) {
+   $content .= "\t<section>$key</section>\n";
+  }
+  foreach $key (sort(keys %objects)) {
+   $content .= "\t<object name=\"$key\">\n";
+   $flags = $objects{$key};
+   $flags =~ s/^<(.*)>$/$1/;
+   my ($annflag,$typesflag,$bodyflag) = split /,/,$flags;
+   $content .= "\t\t<ann value=\"$annflag\" />\n";
+   $content .= "\t\t<types value=\"$typesflag\" />\n";
+   $content .= "\t\t<body value=\"$bodyflag\" />\n";
+   $content .= "\t</object>\n";
+  }
+  $content .= "</ls>\n";
+ } else { # may not enter this branch
+  die "Getter internal error: invalid format received by finduris sub";
+ }
+ return $content;
+}
+
+sub add_flag {
+# manage string like: "<ann_flag,type_flag,body_flag>"
+# "ann_flag" may be one of "ann_YES", "ann_NO"
+# "type_flag" may be one of "types_NO", "types_YES", "types_ANN"
+# "body_flag" may be one of "body_NO", "body_YES", "body_ANN"
+# when adding a flag the max between the current flag and the new flag
+# is taken, the orders are ann_NO < ann_YES, types_NO < types_YES <
+# types_ANN and body_NO < body_YES < body_ANN
+ my ($flagtype,$newflag,$str) = @_;
+ $str = "<,,>" if ($str eq "");
+ ($str =~ s/^<(.*,.*,.*)>$/$1/) or die "Internal error: ".
+   "wrong string format for flag adding in $str";
+ my ($annflag,$typeflag,$bodyflag) = split /,/,$str;
+ if ($flagtype eq "ann") { # ANN flag handling
+  if ($newflag eq "YES") {
+   $annflag = "YES";
+  } elsif ($newflag eq "NO") {
+   $annflag = "NO" unless ($annflag eq "YES");
+  } else {
+   die "Internal error: annflag must be \"YES\" or \"NO\"";
+  }
+ } elsif ($flagtype eq "types") { # TYPES flag handling
+  if ($newflag eq "ANN") {
+   $typeflag = "ANN";
+  } elsif ($newflag eq "YES") {
+   $typeflag = "YES" unless ($typeflag eq "ANN");
+  } elsif ($newflag eq "NO") {
+   $typeflag = "NO"
+     unless (($typeflag eq "ANN") or ($typeflag eq "YES"));
+  } else {
+   die "Internal error: typeflag must be \"YES\", \"NO\" or \"ANN\"";
+  }
+ } elsif ($flagtype eq "body") { # BODY flag handling
+  if ($newflag eq "ANN") {
+   $bodyflag = "ANN";
+  } elsif ($newflag eq "YES") {
+   $bodyflag = "YES" unless ($bodyflag eq "ANN");
+  } elsif ($newflag eq "NO") {
+   $bodyflag = "NO"
+     unless (($bodyflag eq "ANN") or ($bodyflag eq "YES"));
+  } else {
+   die "Internal error: typeflag must be \"YES\", \"NO\" or \"ANN\"";
+  }
+ } else {
+  die "Internal error: unsupported flagtype \"$flagtype\"";
+ }
+ $str = "<$annflag,$typeflag,$bodyflag>";
+}
 
 #CSC: Too much powerful: creates even /home, /home/users/, ...
 #CSC: Does not raise errors if could not create dirs/files
@@ -297,16 +661,12 @@ sub mkdirs
 
 sub print_request
 {
- my ($str,$uri,$url,$filename) = @_;
- print $str."uri: $uri\n";
- print $str."url: $url\n";
- print $str."filename: $filename\n\n";
-}
-
-sub callback
-{
- my ($data) = @_;
- $cont .= $data;
+ my ($uri,$url,$filename) = @_;
+ print "<download_request>\n";
+ print "uri: $uri\n";
+ print "url: $url\n";
+ print "filename: $filename\n\n";
+ print "</download_request>\n";
 }
 
 sub gunzip { # gunzip a file and return the deflated content
@@ -329,20 +689,24 @@ sub gunzip { # gunzip a file and return the deflated content
 
 sub gzip {	# gzip the content argument and save it to filename argument
 	my ($cont, $filename) = @_;
+ #my $debug=1; # debug only
 
-	my ($gz, $cont);
-
-	$gz = gzopen($filename, "w")
+ print "gzopening $filename ...\n" if (defined($debug));
+	my $gz = gzopen($filename, "w")
 		or die "Cannot gzopen for writing file $filename: $gzerrno";
-	$gz->gzwrite($cont) or die "error writing: $gzerrno\n" ;
+ print "gzwriting ...\n" if (defined($debug));
+	$gz->gzwrite($cont) or die "error writing: $gzerrno, exiting!\n";
+ print "gzclosing ...\n" if (defined($debug));
 	$gz->gzclose();
 }
 
-sub download
-{
- my ($remove_headers,$str,$url,$filename) = @_;
+sub download {
+ my ($patch_dtd,$url,$filename,$format) = @_;
  my ($gz, $buffer);
 
+# print "DOWNLOAD subs receives url: \"$url\"\n";
+# print "DOWNLOAD subs receives filename: \"$filename\"\n";
+
  my $resourcetype;	# retrieve mode: "normal" (.xml) or "gzipped" (.xml.gz)
  if ($filename =~ /\.xml$/) {	# set retrieve mode
 	 $resourcetype = "normal";
@@ -363,7 +727,7 @@ sub download
  }
  if ($localfname ne "") { # we already have local copy of requested file
       # check both possible cache entry: gzipped or normal
-  print "Using local copy for the $str file\n";
+  print "Using local copy.\n";
   if ($localfname =~ /\.xml\.gz$/) { # deflating cached file and return it
    $cont = gunzip($localfname);
   } elsif ($localfname =~ /\.xml$/) { # just return cached file
@@ -375,63 +739,226 @@ sub download
    ."must end with '.gz' or '.xml.gz'\n";
   }
  } else { # download file from net
-    print "Downloading the $str file\n"; # download file
-    $ua = LWP::UserAgent->new;
-    $request = HTTP::Request->new(GET => "$url");
-    $response = $ua->request($request, \&callback);
-               
-    # cache retrieved file to disk
-# <ZACK/> TODO: inefficent, I haven't yet undestood how to deflate
-#    in memory gzipped file, without call "gzopen"
- print "Storing the $str file\n";
- mkdirs($filename);
- open(FD, ">".$filename.".tmp") or die "Cannot open $filename.tmp\n";
- print FD $cont;
- close(FD);
-
- # handle cache conversion normal->gzipped or gzipped->normal as user choice
- if (($cachemode eq 'normal') and ($resourcetype eq 'normal')) {
-   # cache the file as is
-  rename "$filename.tmp", $filename; 
- } elsif (($cachemode eq 'gzipped') and ($resourcetype eq 'gzipped')) {
-   # cache the file as is
-   # and update the $cont variabile with deflated content
-  rename "$filename.tmp", $filename; 
-  $cont = gunzip($filename);
- } elsif (($cachemode eq 'normal') and ($resourcetype eq 'gzipped')) {
-   # deflate cache entry
-   # and update $cont
-  open(FD, "> $basefname") or die "cannot open $basefname\n";
-  $cont = gunzip($filename.".tmp");
-  print FD $cont;
-  close(FD);
-  unlink "$filename.tmp"; # delete old gzipped file
- } elsif (($cachemode eq 'gzipped') and ($resourcetype eq 'normal')) {
-   # compress cache entry
-  gzip($cont, $basefname.".gz");
-  unlink "$filename.tmp"; # delete old uncompressed file
- } else {
-  die "Internal error, unsopported cachemode, resourcetype couple\n";
- }
- # $cont now contained uncompressed data
+   print "Downloading file ...\n"; # download file
+   my $ua = LWP::UserAgent->new;
+   my $request = HTTP::Request->new(GET => "$url");
+   my $response = $ua->request($request, \&callback);
+   
+   # cache retrieved file to disk
+   # <ZACK/> TODO: inefficent, I haven't yet undestood how to deflate
+   #    in memory gzipped file, without call "gzopen"
+   print "Storing file ...\n";
+#   print "Making dirs ...\n";
+   mkdirs($filename);
+#   print "Opening tmp file for writing ...\n";
+   open(FD, ">".$filename.".tmp") or die "Cannot open $filename.tmp\n";
+#   print "Writing on tmp file ...\n";
+   print FD $cont;
+#   print "Closing tmp file ...\n";
+   close(FD);
 
+   # handle cache conversion normal->gzipped or gzipped->normal as user choice
+   print "cachemode:$cachemode, resourcetype:$resourcetype\n"
+    if (defined($debug));
+   if (($cachemode eq 'normal') and ($resourcetype eq 'normal')) {
+     # cache the file as is
+    rename "$filename.tmp", $filename; 
+   } elsif (($cachemode eq 'gzipped') and ($resourcetype eq 'gzipped')) {
+     # cache the file as is
+     # and update the $cont variabile with deflated content
+    rename "$filename.tmp", $filename; 
+    $cont = gunzip($filename);
+   } elsif (($cachemode eq 'normal') and ($resourcetype eq 'gzipped')) {
+     # deflate cache entry
+     # and update $cont
+    open(FD, "> $basefname") or die "cannot open $basefname\n";
+    $cont = gunzip($filename.".tmp");
+    print FD $cont;
+    close(FD);
+    unlink "$filename.tmp"; # delete old gzipped file
+   } elsif (($cachemode eq 'gzipped') and ($resourcetype eq 'normal')) {
+     # compress cache entry
+    print "gzipping ...\n" if (defined($debug));
+    gzip($cont, $basefname.".gz");
+    unlink "$filename.tmp"; # delete old uncompressed file
+   } else {
+    die "Internal error, unsopported cachemode, resourcetype couple\n";
+   }
+   # $cont now contained uncompressed data
  }
- if ($remove_headers) {
-    $cont =~ s/<\?xml [^?]*\?>//sg;
-    $cont =~ s/<!DOCTYPE [^>]*>//sg;
+ if ($patch_dtd eq "yes") {
+    $cont =~ s/DOCTYPE (.*) SYSTEM\s+"$dtdbaseurl\//DOCTYPE $1 SYSTEM "$myownurl\/getdtd?uri=/g;
+ }
+ if ($format eq "gz") {
+  gzip($cont,"$basefname.tmp");
+  open (TMP, "< $basefname.tmp")
+   or die "Can't open tempfile: $filename.tmp, exiting!\n";
+  $cont = "";
+  while(<TMP>) {
+   $cont .= $_;
+  }
+  close TMP;
+  unlink ($basefname . ".tmp") or
+   die "cannot unlink temporary file: $basefname.tmp\n";
  }
+
  return $cont;
 }
 
-sub answer
-{
- my ($c,$cont) = @_;
+sub answer {
+# answer the client setting content, Content-Type and Content-Enconding
+# of the answer
+ my ($c,$cont,$contype,$contenc) = @_;
  my $res = new HTTP::Response;
  $res->content($cont);
+ $res->push_header("Content-Type" => $contype)
+   unless ($contype eq "");
+ $res->push_header("Content-Encoding" => $contenc)
+   unless ($contenc eq "");
+ $res->push_header("Cache-Control" => "no-cache");
+ $res->push_header("Pragma" => "no-cache");
+ $res->push_header("Expires" => "0");
  $c->send_response($res);
+ $c->force_last_request();
+}
+
+sub html_nice_answer {
+# answer the client whith a nice html document
+ my ($c,$content) = @_;
+ $content = "<html><body><h1>$content</h1></body></html>";
+ answer($c,$content,"text/html","");
+}
+
+sub callback {
+ my ($data) = @_;
+ $cont .= $data;
+}
+
+sub helm_wget {
+# retrieve a file from an url and write it to a temp dir
+# used for retrieve resource index from servers
+ $cont = "";
+ my ($prefix, $URL) = @_;
+ my $ua = LWP::UserAgent->new;
+ my $request = HTTP::Request->new(GET => "$URL");
+ my $response = $ua->request($request, \&callback);
+ my ($filename) = reverse (split "/", $URL); # get filename part of the URL
+ open (TEMP, "> $prefix/$filename")
+  || die "Cannot open temporary file: $prefix/$filename\n";
+ print TEMP $cont;
+ close TEMP;
 }
 
 sub update {
- untie %map;
- tie(%map, 'DB_File', $uris_dbm.".db", O_RDONLY, 0664);
+# retie dbs
+ untie %xml_map;
+ tie(%xml_map, 'DB_File', $uris_dbm, O_RDWR, 0664);
+ untie %rdf_map;
+ tie(%rdf_map, 'DB_File', $rdf_dbm, O_RDWR, 0664);
+ untie %xslt_map;
+ tie(%xslt_map, 'DB_File', $xslt_dbm, O_RDWR, 0664);
 }
+
+sub update_dbs {
+# rebuild dbs fetching resource indexes from servers.
+# Rebuild urls_of_uris db (1), rdf db (2) and xslt db (3)
+ my (
+  $server, $idxfile, $rdf_idxfile, $uri, $url, $comp, $line,
+  @servers,
+  %urls_of_uris, %rdf, %xslt # local proxy of dbs
+ );
+
+ untie %xml_map;
+ untie %rdf_map;
+ untie %xslt_map;
+ foreach my $file ($uris_dbm, $rdf_dbm, $xslt_dbm) { # remove old db file
+  if (stat $file) { # remove if exists
+   unlink ($file) or die "can't unlink old db file: $file\n";
+  }
+ }
+ tie(%urls_of_uris, 'DB_File', $uris_dbm, O_RDWR|O_CREAT, 0664);
+ tie(%rdf, 'DB_File', $rdf_dbm, O_RDWR|O_CREAT, 0664);
+ tie(%xslt, 'DB_File', $xslt_dbm, O_RDWR|O_CREAT, 0664);
+
+ open (SRVS, "< $servers_file") or
+  die "cannot open servers file: $servers_file\n";
+ @servers = <SRVS>; # read all servers
+ close (SRVS);
+
+ while ($server = pop @servers) { # cicle on servers in _reverse_ order
+  print "processing server: $server ...\n";
+  chomp $server;
+  helm_wget($tmp_dir, $server."/".$indexname); # get index
+  helm_wget($tmp_dir, $server."/".$rdf_indexname); # get rdf index
+  helm_wget($tmp_dir, $server."/".$xslt_indexname); # get xslt index
+  $idxfile = $tmp_dir."/".$indexname;
+  $rdf_idxfile = $tmp_dir."/".$rdf_indexname;
+  $xslt_idxfile = $tmp_dir . "/" . $xslt_indexname;
+
+                  # (1) REBUILD URLS_OF_URIS DB
+  open (INDEX, "< $idxfile") or
+   die "cannot open temporary index file: $idxfile\n";
+  while (my $line = <INDEX>) {  # parse index and add entry to urls_of_uris db
+   chomp $line;
+   ($uri,$comp) = split /[ \t]+/, $line;
+             # build url:
+   if ($comp =~ /gz/) { 
+    $url = $uri . ".xml" . ".gz";
+   } else {
+    $url = $uri . ".xml";
+   }
+   $url =~ s/cic:/$server/;
+   $url =~ s/theory:/$server/;
+   $urls_of_uris{$uri} = $url;
+  }
+
+                  # (2) REBUILD RDF DB
+  open (RDF_INDEX, "< $rdf_idxfile") or
+   die "cannot open temporary RDF index file: $rdf_idxfile\n";
+  while (my $line = <RDF_INDEX>) {  # parse index and add entry to rdf db
+   chomp $line;
+   ($uri,$comp) = split /[ \t]+/, $line; # comp is "gz" or nothing
+             # build url:
+   if ($comp =~ /gz/) { 
+    $url = $uri . ".xml" . ".gz";
+   } else {
+    $url = $uri . ".xml";
+   }
+   $url =~ s/^helm:rdf(.*)\/\/cic:/$server/;
+   $url =~ s/^helm:rdf(.*)\/\/theory:/$server/;
+   $rdf{$uri} = $url;
+  }
+
+                  # (3) REBUILD XSLT DB
+  open (XSLT_INDEX, "< $xslt_idxfile") or
+    die "cannot open temporary XSLT index file: $xslt_idxfile\n";
+  while (my $line = <XSLT_INDEX>) { # parse index and add entry to xslt db
+    chomp $line;
+    my $stylesheet = $line;
+    my $url = $server . "/" . $stylesheet;
+    $xslt{$stylesheet} = $url;
+  }
+
+  close INDEX;  # close indexes
+  close RDF_INDEX;
+  close XSLT_INDEX;
+
+                  # remove temp files
+  foreach my $file ($idxfile, $rdf_idxfile, $xslt_idxfile) {
+    print "cannot unlink temporary file: $file\n" if (unlink $file) != 1;
+  }
+
+ }
+
+ untie(%urls_of_uris); # untie local proxies
+ untie(%rdf);
+ untie(%xslt);
+ tie(%xml_map, 'DB_File', $uris_dbm, O_RDWR, 0664); # retie global ones
+ tie(%rdf_map, 'DB_File', $rdf_dbm, O_RDWR, 0664);
+ tie(%xslt_map, 'DB_File', $xslt_dbm, O_RDWR, 0664);
+
+} # update_dbs
+
+# vim modline: do not remove!
+# vim: set ft=perl:
+