--- rat/lonuserstate.pm	2005/03/15 17:21:42	1.85
+++ rat/lonuserstate.pm	2006/02/23 08:38:54	1.99.2.1
@@ -1,7 +1,7 @@
 # The LearningOnline Network with CAPA
 # Construct and maintain state and binary representation of course for user
 #
-# $Id: lonuserstate.pm,v 1.85 2005/03/15 17:21:42 albertel Exp $
+# $Id: lonuserstate.pm,v 1.99.2.1 2006/02/23 08:38:54 albertel Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -31,10 +31,8 @@ package Apache::lonuserstate;
 
 # ------------------------------------------------- modules used by this module
 use strict;
-use Apache::Constants qw(:common :http);
-use Apache::File;
 use HTML::TokeParser;
-use Apache::lonnet();
+use Apache::lonnet;
 use Apache::loncommon();
 use GDBM_File;
 use Apache::lonmsg;
@@ -42,6 +40,7 @@ use Safe;
 use Safe::Hole;
 use Opcode;
 use Apache::lonenc;
+use Fcntl qw(:flock);
 
 # ---------------------------------------------------- Globals for this package
 
@@ -74,6 +73,7 @@ sub versiontrack {
 
 sub putinversion {
     my $uri=shift;
+    my $key=$env{'request.course.id'}.'_'.&Apache::lonnet::clutter($uri);
     if ($hash{'version_'.$uri}) {
 	my $version=$hash{'version_'.$uri};
 	if ($version eq 'mostrecent') { return $uri; }
@@ -82,6 +82,7 @@ sub putinversion {
 	             { return $uri; }
 	$uri=~s/\.(\w+)$/\.$version\.$1/;
     }
+    &Apache::lonnet::do_cache_new('courseresversion',$key,&Apache::lonnet::declutter($uri),600);
     return $uri;
 }
 
@@ -102,7 +103,7 @@ sub processversionfile {
 
 sub loadmap { 
     my $uri=shift;
-    if ($hash{'map_pc_'.$uri}) { return OK; }
+    if ($hash{'map_pc_'.$uri}) { return; }
 
     $pc++;
     my $lpc=$pc;
@@ -117,7 +118,7 @@ sub loadmap {
     unless (($fn=~/\.sequence$/) ||
             ($fn=~/\.page$/)) { 
 	$errtext.="Invalid map: $fn\n";
-	return OK; 
+	return; 
     }
 
     my $instr=&Apache::lonnet::getfile($fn);
@@ -127,6 +128,7 @@ sub loadmap {
 # Successfully got file, parse it
 
         my $parser = HTML::TokeParser->new(\$instr);
+	$parser->attr_encoded(1);
         my $token;
 
         my $linkpc=0;
@@ -139,7 +141,7 @@ sub loadmap {
 	    if ($token->[0] eq 'S') {
                 if ($token->[1] eq 'resource') {
 # -------------------------------------------------------------------- Resource
-
+                    if ($token->[2]->{'type'} eq 'zombie') { next; }
                     my $rid=$lpc.'.'.$token->[2]->{'id'};
 
                     $hash{'kind_'.$rid}='res';
@@ -162,7 +164,9 @@ sub loadmap {
                         if ($token->[2]->{'external'} eq 'true') { # external
                             $turi=~s/^http\:\/\//\/adm\/wrapper\/ext\//;
                         } elsif ($turi=~/^\/*uploaded\//) { # uploaded
-			    if (($embstyle eq 'img') || ($embstyle eq 'emb')) {
+			    if (($embstyle eq 'img') 
+				|| ($embstyle eq 'emb')
+				|| ($embstyle eq 'wrp')) {
                                 $turi='/adm/wrapper'.$turi;
 			    } elsif ($embstyle eq 'ssi') {
 				#do nothing with these
@@ -173,7 +177,9 @@ sub loadmap {
 			    my $mapdir=$uri;
 			    $mapdir=~s/[^\/]+$//;
 			    $turi=&Apache::lonnet::hreflocation($mapdir,$turi);
-			    if (($embstyle eq 'img') || ($embstyle eq 'emb')) {
+			    if (($embstyle eq 'img') 
+				|| ($embstyle eq 'emb')
+				|| ($embstyle eq 'wrp')) {
 				$turi='/adm/wrapper'.$turi;
 			    }
                         }
@@ -312,6 +318,8 @@ sub loadmap {
 
 sub simplify {
     my $expression=shift;
+# (0&1) = 1
+    $expression=~s/\(0\&(\d+)\)/$1/g;
 # (8)=8
     $expression=~s/\((\d+)\)/$1/g;
 # 8&8=8
@@ -321,8 +329,8 @@ sub simplify {
 # (5&3)&4=5&3&4
     $expression=~s/\((\d+)((?:\&\d+)+)\)\&(\d+\D)/$1$2\&$3/g;
 # (((5&3)|(4&6)))=((5&3)|(4&6))
-    $expression=~
-	s/\((\(\(\d+(?:\&\d+)*\)(?:\|\(\d+(?:\&\d+)*\))+\))\)/$1/g;
+#    $expression=~
+#	s/\((\(\(\d+(?:\&\d+)*\)(?:\|\(\d+(?:\&\d+)*\))+\))\)/$1/g;
 # ((5&3)|(4&6))|(1&2)=(5&3)|(4&6)|(1&2)
     $expression=~
 	s/\((\(\d+(?:\&\d+)*\))((?:\|\(\d+(?:\&\d+)*\))+)\)\|(\(\d+(?:\&\d+)*\))/\($1$2\|$3\)/g;
@@ -339,7 +347,14 @@ sub traceroute {
 	my ($mapid,$resid)=split(/\./,$rid);
 	my $symb=&Apache::lonnet::encode_symb($hash{'map_id_'.$mapid},$resid,$hash{'src_'.$rid});
 	my $hidden=&Apache::lonnet::EXT('resource.0.hiddenresource',$symb);
-	if ($hdnflag || lc($hidden) eq 'yes') { $hiddenurl{$rid}=1; }
+
+	if ($hdnflag || lc($hidden) eq 'yes') {
+	    $hiddenurl{$rid}=1;
+	}
+	if (!$hdnflag && lc($hidden) eq 'no') {
+	    delete($hiddenurl{$rid});
+	}
+
 	my $encrypt=&Apache::lonnet::EXT('resource.0.encrypturl',$symb);
 	if ($encflag || lc($encrypt) eq 'yes') { $encurl{$rid}=1; }
 	if (($retfurl eq '') && ($hash{'src_'.$rid})
@@ -413,8 +428,8 @@ sub accinit {
 		$acchash{'acc.cond.'.$short.'.'.$condcounter}=$expr;
 	    } 
 	} elsif ($_=~/^param_(\d+)\.(\d+)/) {
-	    my $prefix=&Apache::lonnet::declutter($hash{'map_id_'.$1}).
-		'___'.$2.'___'.&Apache::lonnet::declutter($hash{'src_'.$1.'.'.$2});
+	    my $prefix=&Apache::lonnet::encode_symb($hash{'map_id_'.$1},$2,
+						    $hash{'src_'.$1.'.'.$2});
 	    foreach (split(/\&/,$hash{$_})) {
 		my ($typename,$value)=split(/\=/,$_);
 		my ($type,$name)=split(/\:/,$typename);
@@ -504,11 +519,10 @@ sub hiddenurls {
 		$hash{'randomout_'.$currentrids[$k]}=1;
                 my ($mapid,$resid)=split(/\./,$currentrids[$k]);
                 $randomoutentry.='&'.
-		    &Apache::lonnet::symbclean(
-					       &Apache::lonnet::declutter($hash{'map_id_'.$mapid}).
-					       '___'.$resid.'___'.
-					       &Apache::lonnet::declutter($hash{'src_'.$currentrids[$k]})
-					       ).'&';
+		    &Apache::lonnet::encode_symb($hash{'map_id_'.$mapid},
+						 $resid,
+						 $hash{'src_'.$currentrids[$k]}
+						 ).'&';
             }
         }
     }
@@ -517,11 +531,8 @@ sub hiddenurls {
 	$hash{'randomout_'.$rid}=1;
 	my ($mapid,$resid)=split(/\./,$rid);
 	$randomoutentry.='&'.
-	    &Apache::lonnet::symbclean(
-				       &Apache::lonnet::declutter($hash{'map_id_'.$mapid}).
-				       '___'.$resid.'___'.
-				       &Apache::lonnet::declutter($hash{'src_'.$rid})
-				       ).'&';
+	    &Apache::lonnet::encode_symb($hash{'map_id_'.$mapid},$resid,
+					 $hash{'src_'.$rid}).'&';
     }
 # --------------------------------------- append randomout entry to environment
     if ($randomoutentry) {
@@ -544,15 +555,21 @@ sub readmap {
 	return 'No course data available.';
     }
     @cond=('true:normal');
-    unlink($fn.'.db');
-    unlink($fn.'_symb.db');
-    unlink($fn.'.state');
-    unlink($fn.'parms.db');
+
+    open(LOCKFILE,">$fn.db.lock");
+    my $lock=0;
+    if (flock(LOCKFILE,LOCK_EX|LOCK_NB)) {
+	$lock=1;
+	unlink($fn.'.db');
+	unlink($fn.'_symb.db');
+	unlink($fn.'.state');
+	unlink($fn.'parms.db');
+    }
     undef %randompick;
     undef %hiddenurl;
     undef %encurl;
     $retfurl='';
-    if ((tie(%hash,'GDBM_File',"$fn.db",&GDBM_WRCREAT(),0640)) &&
+    if ($lock && (tie(%hash,'GDBM_File',"$fn.db",&GDBM_WRCREAT(),0640)) &&
 	(tie(%parmhash,'GDBM_File',$fn.'_parms.db',&GDBM_WRCREAT(),0640))) {
 	%hash=();
 	%parmhash=();
@@ -586,6 +603,7 @@ sub readmap {
 	}
 # ----------------------------------------------- Close hashes to finally store
 # --------------------------------- Routine must pass this point, no early outs
+	$hash{'first_url'}=$retfurl;
 	unless ((untie(%hash)) && (untie(%parmhash))) {
 	    &Apache::lonnet::logthis("<font color=blue>WARNING: ".
 				     "Could not untie coursemap $fn for $uri.</font>"); 
@@ -593,22 +611,56 @@ sub readmap {
 # ---------------------------------------------------- Store away initial state
 	{
 	    my $cfh;
-	    if ($cfh=Apache::File->new(">$fn.state")) {
+	    if (open($cfh,">$fn.state")) {
 		print $cfh join("\n",@cond);
 	    } else {
 		&Apache::lonnet::logthis("<font color=blue>WARNING: ".
 					 "Could not write statemap $fn for $uri.</font>"); 
 	    }
-	}  
+	}
+	flock(LOCKFILE,LOCK_UN);
+	close(LOCKFILE);
     } else {
+	# if we are here it is likely because we are already trying to 
+	# initialize the course in another child, busy wait trying to 
+	# tie the hashes for the next 90 seconds, if we succeed forward 
+	# them on to navmaps, if we fail, throw up the Could not init 
+	# course screen
+	if ($lock) {
+	    # Got the lock but not the DB files
+	    flock(LOCKFILE,LOCK_UN);
+	}
+	untie(%hash);
+	untie(%parmhash);
 	&Apache::lonnet::logthis("<font color=blue>WARNING: ".
 				 "Could not tie coursemap $fn for $uri.</font>"); 
+	my $i=0;
+	while($i<90) {
+	    $i++;
+	    sleep(1);
+	    if (flock(LOCKFILE,LOCK_EX|LOCK_NB) &&
+		(tie(%hash,'GDBM_File',"$fn.db",&GDBM_READER(),0640))) {
+		if (tie(%parmhash,'GDBM_File',$fn.'_parms.db',&GDBM_READER(),0640)) {
+		    $retfurl='/adm/navmaps';
+		    &Apache::lonnet::appenv("request.course.id"  => $short,
+					    "request.course.fn"  => $fn,
+					    "request.course.uri" => $uri);
+		    untie(%hash);
+		    untie(%parmhash);
+		    last;
+		}
+	    }
+	    untie(%hash);
+	    untie(%parmhash);
+	}
+	flock(LOCKFILE,LOCK_UN);
+	close(LOCKFILE);
     }
-    &Apache::lonmsg::author_res_msg($ENV{'request.course.uri'},$errtext);
+    &Apache::lonmsg::author_res_msg($env{'request.course.uri'},$errtext);
 # ------------------------------------------------- Check for critical messages
 
-    my @what=&Apache::lonnet::dump('critical',$ENV{'user.domain'},
-				   $ENV{'user.name'});
+    my @what=&Apache::lonnet::dump('critical',$env{'user.domain'},
+				   $env{'user.name'});
     if ($what[0]) {
 	if (($what[0] ne 'con_lost') && ($what[0]!~/^error\:/)) {
 	    $retfurl='/adm/email?critical=display';
@@ -620,7 +672,7 @@ sub readmap {
 # ------------------------------------------------------- Evaluate state string
 
 sub evalstate {
-    my $fn=$ENV{'request.course.fn'}.'.state';
+    my $fn=$env{'request.course.fn'}.'.state';
     my $state='';
     if (-e $fn) {
 	my @conditions=();
@@ -652,7 +704,7 @@ sub evalstate {
 	    }
 	}
     }
-    &Apache::lonnet::appenv('user.state.'.$ENV{'request.course.id'} => $state);
+    &Apache::lonnet::appenv('user.state.'.$env{'request.course.id'} => $state);
     return $state;
 }