--- loncom/lonnet/perl/lonnet.pm	2003/09/02 13:07:51	1.408
+++ loncom/lonnet/perl/lonnet.pm	2003/09/19 16:53:35	1.417
@@ -1,7 +1,7 @@
 # The LearningOnline Network
 # TCP networking package
 #
-# $Id: lonnet.pm,v 1.408 2003/09/02 13:07:51 www Exp $
+# $Id: lonnet.pm,v 1.417 2003/09/19 16:53:35 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 
+   %usectioncache %domaindescription %domain_auth_def %domain_auth_arg_def 
    %domain_lang_def %domain_city %domain_longi %domain_lati $tmpdir);
 
 use IO::Socket;
@@ -85,6 +85,7 @@ use Apache::Constants qw(:common :http);
 use HTML::LCParser;
 use Fcntl qw(:flock);
 use Apache::loncoursedata;
+use Apache::lonlocal;
 
 my $readit;
 
@@ -246,9 +247,13 @@ sub critical {
     return $answer;
 }
 
+#
 # -------------- Remove all key from the env that start witha lowercase letter
-#                (Which is alweways a lon-capa value)
+#                (Which is always a lon-capa value)
+
 sub cleanenv {
+#    unless (defined(&Apache::exists_config_define("MODPERL2"))) { return; }
+#    unless (&Apache::exists_config_define("MODPERL2")) { return; }
     foreach my $key (keys(%ENV)) {
 	if ($key =~ /^[a-z]/) {
 	    delete($ENV{$key});
@@ -436,15 +441,27 @@ sub spareserver {
     my $lowestserver=$loadpercent > $userloadpercent?
 	             $loadpercent :  $userloadpercent;
     foreach $tryserver (keys %spareid) {
-       my $loadans=reply('load',$tryserver);
-       my $userloadans=reply('userload',$tryserver);
-       if ($userloadans !~ /\d/) { $userloadans=0; }
-       my $answer=$loadans > $userloadans?
-                  $loadans :  $userloadans;
-       if (($answer =~ /\d/) && ($answer<$lowestserver)) {
-	   $spareserver="http://$hostname{$tryserver}";
-           $lowestserver=$answer;
-       }
+	my $loadans=reply('load',$tryserver);
+	my $userloadans=reply('userload',$tryserver);
+	if ($loadans !~ /\d/ && $userloadans !~ /\d/) {
+	    next; #didn't get a number from the server
+	}
+	my $answer;
+	if ($loadans =~ /\d/) {
+	    if ($userloadans =~ /\d/) {
+		#both are numbers, pick the bigger one
+		$answer=$loadans > $userloadans?
+		    $loadans :  $userloadans;
+	    } else {
+		$answer = $loadans;
+	    }
+	} else {
+	    $answer = $userloadans;
+	}
+	if (($answer =~ /\d/) && ($answer<$lowestserver)) {
+	    $spareserver="http://$hostname{$tryserver}";
+	    $lowestserver=$answer;
+	}
     }
     return $spareserver;
 }
@@ -831,8 +848,38 @@ 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 (!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,$hashid,300);
+    if (defined($cached)) { return $result; }
     $courseid=~s/\_/\//g;
     $courseid=~s/^(\w)/\/$1/;
     foreach (split(/\&/,&reply('dump:'.$udom.':'.$unam.':roles',
@@ -851,10 +898,12 @@ sub usection {
             if ($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
@@ -2590,7 +2639,10 @@ sub is_on_map {
     if ($match) {
 	return (1,$1);
     } else {
-	return (0,0);
+	my ($name,$ext)=($filename=~/^(.+)\.(\w+)$/);
+        $ENV{'acc.res.'.$ENV{'request.course.id'}.'.'.$pathname}=~
+	       /\&(\Q$name\E\.\d+\.$ext)\:([\d\|]+)\&/;
+	return (0,$2,$pathname.'/'.$1);
     }
 }
 
@@ -2720,7 +2772,7 @@ sub userlog_query {
 
 sub plaintext {
     my $short=shift;
-    return $prp{$short};
+    return &mt($prp{$short});
 }
 
 # ----------------------------------------------------------------- Assign Role
@@ -3165,6 +3217,13 @@ sub dirlist {
 # when it was last modified.  It will also return an error of -1
 # if an error occurs
 
+##
+## FIXME: This subroutine assumes its caller knows something about the
+## directory structure of the home server for the student ($root).
+## Not a good assumption to make.  Since this is for looking up files
+## in user directories, the full path should be constructed by lond, not
+## whatever machine we request data from.
+##
 sub GetFileTimestamp {
     my ($studentDomain,$studentName,$filename,$root)=@_;
     $studentDomain=~s/\W//g;
@@ -3250,25 +3309,23 @@ sub courseresdata {
     my ($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,$hashid,300);
+    unless (defined($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;
@@ -3410,7 +3467,7 @@ sub EXT {
 # ----------------------------------------------------- Cascading lookup scheme
 	    if (!$symbparm) { $symbparm=&symbread(); }
 	    my $symbp=$symbparm;
-	    my $mapp=(split(/\_\_\_/,$symbp))[0];
+	    my $mapp=(&decode_symb($symbp))[0];
 
 	    my $symbparm=$symbp.'.'.$spacequalifierrest;
 	    my $mapparm=$mapp.'___(all).'.$spacequalifierrest;
@@ -3489,7 +3546,7 @@ sub EXT {
 	my $filename;
 	if (!$symbparm) { $symbparm=&symbread(); }
 	if ($symbparm) {
-	    $filename=(split(/\_\_\_/,$symbparm))[2];
+	    $filename=(&decode_symb($symbparm))[2];
 	} else {
 	    $filename=$ENV{'request.filename'};
 	}
@@ -3764,7 +3821,7 @@ sub gettitle {
 	    delete($titlecache{$symb});
 	}
     }
-    my ($map,$resid,$url)=split(/\_\_\_/,$symb);
+    my ($map,$resid,$url)=&decode_symb($symb);
     my $title='';
     my %bighash;
     if (tie(%bighash,'GDBM_File',$ENV{'request.course.fn'}.'.db',
@@ -3810,7 +3867,7 @@ sub symbverify {
 # direct jump to resource in page or to a sequence - will construct own symbs
     if ($thisfn=~/\.(page|sequence)$/) { return 1; }
 # check URL part
-    my ($map,$resid,$url)=split(/\_\_\_/,$symb);
+    my ($map,$resid,$url)=&decode_symb($symb);
     unless (&symbclean($url) eq &symbclean($thisfn)) { return 0; }
 
     $symb=&symbclean($symb);
@@ -3853,6 +3910,23 @@ sub symbclean {
     return $symb;
 }
 
+# ---------------------------------------------- Split symb to find map and url
+
+sub decode_symb {
+    my ($map,$resid,$url)=split(/\_\_\_/,shift);
+    return (&fixversion($map),$resid,&fixversion($url));
+}
+
+sub fixversion {
+    my $fn=shift;
+    if ($fn=~/^(adm|uploaded|public)/) { return $fn; }
+    my ($match,$cond,$versioned)=&is_on_map($fn);
+    unless ($match) {
+	$fn=$versioned;
+    }
+    return $fn;
+}
+
 # ------------------------------------------------------ Return symb list entry
 
 sub symbread {
@@ -4152,6 +4226,12 @@ sub unescape {
     return $str;
 }
 
+sub mod_perl_version {
+    if (defined($perlvar{'MODPERL2'})) {
+	return 2;
+    }
+    return 1;
+}
 # ================================================================ Main Program
 
 sub goodbye {