--- loncom/lonnet/perl/lonnet.pm	2003/09/17 01:45:14	1.414
+++ loncom/lonnet/perl/lonnet.pm	2003/09/25 20:02:54	1.423
@@ -1,7 +1,7 @@
 # The LearningOnline Network
 # TCP networking package
 #
-# $Id: lonnet.pm,v 1.414 2003/09/17 01:45:14 www Exp $
+# $Id: lonnet.pm,v 1.423 2003/09/25 20:02:54 albertel Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -76,7 +76,7 @@ qw(%perlvar %hostname %homecache %badSer
    %libserv %pr %prp %metacache %packagetab %titlecache 
    %courselogs %accesshash %userrolehash $processmarker $dumpcount 
    %coursedombuf %coursenumbuf %coursehombuf %coursedescrbuf %courseresdatacache 
-   %domaindescription %domain_auth_def %domain_auth_arg_def 
+   %userresdatacache %usectioncache %domaindescription %domain_auth_def %domain_auth_arg_def 
    %domain_lang_def %domain_city %domain_longi %domain_lati $tmpdir);
 
 use IO::Socket;
@@ -848,8 +848,39 @@ sub getsection {
     return '-1';
 }
 
+sub devalidate_cache {
+    my ($cache,$id) = @_;
+    delete $$cache{$id.'.time'};
+    delete $$cache{$id};
+}
+
+sub is_cached {
+    my ($cache,$id,$time) = @_;
+    if (!$time) { $time=300; }
+    if (!exists($$cache{$id.'.time'})) {
+	return (undef,undef);
+    } else {
+	if (time-$$cache{$id.'.time'}>$time) {
+	    &devalidate_cache($cache,$id);
+	    return (undef,undef);
+	}
+    }
+    return ($$cache{$id},1);
+}
+
+sub do_cache {
+    my ($cache,$id,$value) = @_;
+    $$cache{$id.'.time'}=time;
+    # do_cache implictly return the set value
+    $$cache{$id}=$value;
+}
+
 sub usection {
     my ($udom,$unam,$courseid)=@_;
+    my $hashid="$udom:$unam:$courseid";
+    
+    my ($result,$cached)=&is_cached(\%usectioncache,$hashid);
+    if (defined($cached)) { return $result; }
     $courseid=~s/\_/\//g;
     $courseid=~s/^(\w)/\/$1/;
     foreach (split(/\&/,&reply('dump:'.$udom.':'.$unam.':roles',
@@ -868,10 +899,12 @@ sub usection {
             if ($end) {
                 if ($now>$end) { $notactive=1; }
             } 
-            unless ($notactive) { return $section; }
+            unless ($notactive) {
+		return &do_cache(\%usectioncache,$hashid,$section);
+	    }
         }
     }
-    return '-1';
+    return &do_cache(\%usectioncache,$hashid,'-1');
 }
 
 # ------------------------------------- Read an entry from a user's environment
@@ -3268,7 +3301,7 @@ sub condval {
 sub devalidatecourseresdata {
     my ($coursenum,$coursedomain)=@_;
     my $hashid=$coursenum.':'.$coursedomain;
-    delete $courseresdatacache{$hashid.'.time'};
+    &devalidate_cache(\%courseresdatacache,$hashid);
 }
 
 # --------------------------------------------------- Course Resourcedata Query
@@ -3277,25 +3310,23 @@ sub courseresdata {
     my ($coursenum,$coursedomain,@which)=@_;
     my $coursehom=&homeserver($coursenum,$coursedomain);
     my $hashid=$coursenum.':'.$coursedomain;
-    my $dodump=0;
-    if (!defined($courseresdatacache{$hashid.'.time'})) {
-	$dodump=1;
-    } else {
-	if (time-$courseresdatacache{$hashid.'.time'}>300) { $dodump=1; }
-    }
-    if ($dodump) {
+    my ($result,$cached)=&is_cached(\%courseresdatacache,$hashid);
+    unless (defined($cached)) {
 	my %dumpreply=&dump('resourcedata',$coursedomain,$coursenum);
+	$result=\%dumpreply;
 	my ($tmp) = keys(%dumpreply);
 	if ($tmp !~ /^(con_lost|error|no_such_host)/i) {
-	    $courseresdatacache{$hashid.'.time'}=time;
-	    $courseresdatacache{$hashid}=\%dumpreply;
+	    &do_cache(\%courseresdatacache,$hashid,$result);
 	} elsif ($tmp =~ /^(con_lost|no_such_host)/) {
 	    return $tmp;
+	} elsif ($tmp =~ /^(error)/) {
+	    $result=undef;
+	    &do_cache(\%courseresdatacache,$hashid,$result);
 	}
     }
     foreach my $item (@which) {
-	if (defined($courseresdatacache{$hashid}->{$item})) {
-	    return $courseresdatacache{$hashid}->{$item};
+	if (defined($result->{$item})) {
+	    return $result->{$item};
 	}
     }
     return undef;
@@ -3463,28 +3494,35 @@ sub EXT {
 
 # ----------------------------------------------------------- first, check user
 	    #most student don\'t have any data set, check if there is some data
-            #every thirty minutes
 	    if (! &EXT_cache_status($udom,$uname)) {
-		my %resourcedata=&get('resourcedata',
-				      [$courselevelr,$courselevelm,$courselevel],
-				      $udom,$uname);
-		my ($tmp)=keys(%resourcedata);
+		my $hashid="$udom:$uname";
+		my ($result,$cached)=&is_cached(\%userresdatacache,$hashid);
+		if (!defined($cached)) { 
+		    my %resourcedata=&get('resourcedata',
+					  [$courselevelr,$courselevelm,
+					   $courselevel],$udom,$uname);
+		    $result=\%resourcedata;
+		}
+		my ($tmp)=keys(%$result);
 		if (($tmp!~/^error\:/) && ($tmp!~/^con_lost/)) {
-		    if ($resourcedata{$courselevelr}) {
-			return $resourcedata{$courselevelr}; }
-		    if ($resourcedata{$courselevelm}) {
-			return $resourcedata{$courselevelm}; }
-		    if ($resourcedata{$courselevel}) {
-			return $resourcedata{$courselevel}; }
+		    &do_cache(\%userresdatacache,$hashid,$result);
+		    if ($$result{$courselevelr}) {
+			return $$result{$courselevelr}; }
+		    if ($$result{$courselevelm}) {
+			return $$result{$courselevelm}; }
+		    if ($$result{$courselevel}) {
+			return $$result{$courselevel}; }
 		} else {
 		    if ($tmp!~/No such file/) {
 			&logthis("<font color=blue>WARNING:".
 				 " Trying to get resource data for ".
 				 $uname." at ".$udom.": ".
 				 $tmp."</font>");
+			&do_cache(\%userresdatacache,$hashid,undef);
 		    } elsif ($tmp=~/error:No such file/) {
                         &EXT_cache_set($udom,$uname);
 		    } elsif ($tmp =~ /^(con_lost|no_such_host)/) {
+			&do_cache(\%userresdatacache,$hashid,undef);
 			return $tmp;
 		    }
 		}
@@ -3591,11 +3629,11 @@ sub add_prefix_and_part {
 
 sub metadata {
     my ($uri,$what,$liburi,$prefix,$depthcount)=@_;
-
     $uri=&declutter($uri);
     # if it is a non metadata possible uri return quickly
     if (($uri eq '') || (($uri =~ m|^/*adm/|) && ($uri !~ m|^adm/includes|)) ||
-        ($uri =~ m|/$|) || ($uri =~ m|/.meta$|)) {
+        ($uri =~ m|/$|) || ($uri =~ m|/.meta$|) || ($uri =~ /^~/) ||
+	($uri =~ m|home/[^/]+/public_html/|)) {
 	return '';
     }
     my $filename=$uri;
@@ -3784,13 +3822,8 @@ sub gettitle {
 	unless ($urlsymb) { $urlsymb=$ENV{'request.filename'}; }
         return &metadata($urlsymb,'title'); 
     }
-    if ($titlecache{$symb}) {
-	if (time < ($titlecache{$symb}[1] + 600)) {
-	    return $titlecache{$symb}[0];
-	} else {
-	    delete($titlecache{$symb});
-	}
-    }
+    my ($result,$cached)=&is_cached(\%titlecache,$symb,600);
+    if (defined($cached)) { return $result; }
     my ($map,$resid,$url)=&decode_symb($symb);
     my $title='';
     my %bighash;
@@ -3802,8 +3835,7 @@ sub gettitle {
     }
     $title=~s/\&colon\;/\:/gs;
     if ($title) {
-        $titlecache{$symb}=[$title,time];
-        return $title;
+        return &do_cache(\%titlecache,$symb,$title);
     } else {
 	return &metadata($urlsymb,'title');
     }
@@ -4196,6 +4228,12 @@ sub unescape {
     return $str;
 }
 
+sub mod_perl_version {
+    if (defined($perlvar{'MODPERL2'})) {
+	return 2;
+    }
+    return 1;
+}
 # ================================================================ Main Program
 
 sub goodbye {