Diff for /rat/lonuserstate.pm between versions 1.132 and 1.153

version 1.132, 2009/11/15 14:08:53 version 1.153, 2017/09/03 18:52:23
Line 42  use Safe::Hole; Line 42  use Safe::Hole;
 use Opcode;  use Opcode;
 use Apache::lonenc;  use Apache::lonenc;
 use Fcntl qw(:flock);  use Fcntl qw(:flock);
 use LONCAPA;  use LONCAPA qw(:DEFAULT :match);
   use File::Basename;
   
     
   
 # ---------------------------------------------------- Globals for this package  # ---------------------------------------------------- Globals for this package
   
 my $pc;      # Package counter  my $pc;      # Package counter is this what 'Guts' calls the map counter?
 my %hash;    # The big tied hash  my %hash;    # The big tied hash
 my %parmhash;# The hash with the parameters  my %parmhash;# The hash with the parameters
 my @cond;    # Array with all of the conditions  my @cond;    # Array with all of the conditions
Line 57  my $retfurl; # first URL Line 59  my $retfurl; # first URL
 my %randompick; # randomly picked resources  my %randompick; # randomly picked resources
 my %randompickseed; # optional seed for randomly picking resources  my %randompickseed; # optional seed for randomly picking resources
 my %randomorder; # maps to order contents randomly  my %randomorder; # maps to order contents randomly
   my %randomizationcode; # code used to grade folder for bubblesheet exam 
 my %encurl; # URLs in this folder are supposed to be encrypted  my %encurl; # URLs in this folder are supposed to be encrypted
 my %hiddenurl; # this URL (or complete folder) is supposed to be hidden  my %hiddenurl; # this URL (or complete folder) is supposed to be hidden
   my %rescount; # count of unhidden items in each map
   my %mapcount; # count of unhidden maps in each map
   
 # ----------------------------------- Remove version from URL and store in hash  # ----------------------------------- Remove version from URL and store in hash
   
   sub versionerror {
       my ($uri,$usedversion,$unusedversion)=@_;
       return '<br />'.&mt('Version discrepancy: resource [_1] included in both version [_2] and version [_3]. Using version [_2].',
                       $uri,$usedversion,$unusedversion).'<br />';
   }
   
   #  Removes the version number from a URI and returns the resulting
   #  URI (e.g. mumbly.version.stuff => mumbly.stuff).
   #
   #   If the URI has not been seen with a versio before the
   #   hash{'version_'.resultingURI} is set to the  version number.
   #   If the URI has been seen and the version does not match and error
   #   is added to the error string.
   #
   # Parameters:
   #   URI potentially with a version.
   # Returns:
   #   URI with the version cut out.
   # See above for side effects.
   #
   
 sub versiontrack {  sub versiontrack {
     my $uri=shift;      my $uri=shift;
     if ($uri=~/\.(\d+)\.\w+$/) {      if ($uri=~/\.(\d+)\.\w+$/) {
Line 69  sub versiontrack { Line 95  sub versiontrack {
  $uri=~s/\.\d+\.(\w+)$/\.$1/;   $uri=~s/\.\d+\.(\w+)$/\.$1/;
         unless ($hash{'version_'.$uri}) {          unless ($hash{'version_'.$uri}) {
     $hash{'version_'.$uri}=$version;      $hash{'version_'.$uri}=$version;
  }   } elsif ($version!=$hash{'version_'.$uri}) {
               $errtext.=&versionerror($uri,$hash{'version_'.$uri},$version);
           }
     }      }
     return $uri;      return $uri;
 }  }
Line 104  sub processversionfile { Line 132  sub processversionfile {
     }      }
 }  }
   
 # --------------------------------------------------------- Loads map from disk  # --------------------------------------------------------- Loads from disk
   
   
   #
   #  Loads a map file.
   #  Note that this may implicitly recurse via parse_resource if one of the resources
   #  is itself composed.
   #
   # Parameters:
   #    uri         - URI of the map file.
   #    parent_rid  - Resource id in the map of the parent resource (0.0 for the top level map)
   #    courseid    - Course id for the course for which the map is being loaded
   #
 sub loadmap {   sub loadmap { 
     my ($uri,$parent_rid)=@_;      my ($uri,$parent_rid,$courseid)=@_;
   
       # Is the map already included?
   
     if ($hash{'map_pc_'.$uri}) {       if ($hash{'map_pc_'.$uri}) { 
  $errtext.='<p class="LC_error">'.   $errtext.='<p class="LC_error">'.
     &mt('Multiple use of sequence/page [_1]! The course will not function properly.','<tt>'.$uri.'</tt>').      &mt('Multiple use of sequence/page [_1]! The course will not function properly.','<tt>'.$uri.'</tt>').
     '</p>';      '</p>';
  return;    return; 
     }      }
       # Register the resource in it's map_pc_ [for the URL]
       # map_id.nnn is the nesting level -> to the URI.
   
     $pc++;      $pc++;
     my $lpc=$pc;      my $lpc=$pc;
     $hash{'map_pc_'.$uri}=$lpc;      $hash{'map_pc_'.$uri}=$lpc;
     $hash{'map_id_'.$lpc}=$uri;      $hash{'map_id_'.$lpc}=$uri;
   
 # Determine and check filename      # If the parent is of the form n.m hang this map underneath it in the
       # map hierarchy.
   
       if ($parent_rid =~ /^(\d+)\.\d+$/) {
           my $parent_pc = $1;
           if (defined($hash{'map_hierarchy_'.$parent_pc})) {
               $hash{'map_hierarchy_'.$lpc}=$hash{'map_hierarchy_'.$parent_pc}.','.
                                            $parent_pc;
           } else {
               $hash{'map_hierarchy_'.$lpc}=$parent_pc;
           }
       }
   
   # Determine and check filename of the sequence we need to read:
   
     my $fn=&Apache::lonnet::filelocation('',&putinversion($uri));      my $fn=&Apache::lonnet::filelocation('',&putinversion($uri));
   
     my $ispage=($fn=~/\.page$/);      my $ispage=($fn=~/\.page$/);
   
     unless (($fn=~/\.sequence$/) ||      # We can only nest sequences or pages.  Anything else is an illegal nest.
             ($fn=~/\.page$/)) {   
  $errtext.=&mt("<br />Invalid map: <tt>[_1]</tt>",$fn);      unless (($fn=~/\.sequence$/) || $ispage) { 
    $errtext.='<br />'.&mt('Invalid map: [_1]',"<tt>$fn</tt>");
  return;    return; 
     }      }
   
       # Read the XML that constitutes the file.
   
     my $instr=&Apache::lonnet::getfile($fn);      my $instr=&Apache::lonnet::getfile($fn);
   
     if ($instr eq -1) {      if ($instr eq -1) {
         $errtext.=&mt('<br />Map not loaded: The file <tt>[_1]</tt> does not exist.',$fn);          $errtext.= '<br />'
                     .&mt('Map not loaded: The file [_1] does not exist.',
                          "<tt>$fn</tt>");
  return;   return;
     }      }
   
 # Successfully got file, parse it      # Successfully got file, parse it
   
       # parse for parameter processing.
       # Note that these are <param... / > tags
       # so we only care about 'S' (tag start) nodes.
   
   
     my $parser = HTML::TokeParser->new(\$instr);      my $parser = HTML::TokeParser->new(\$instr);
     $parser->attr_encoded(1);      $parser->attr_encoded(1);
   
     # first get all parameters      # first get all parameters
   
   
     while (my $token = $parser->get_token) {      while (my $token = $parser->get_token) {
  next if ($token->[0] ne 'S');   next if ($token->[0] ne 'S');
  if ($token->[1] eq 'param') {   if ($token->[1] eq 'param') {
     &parse_param($token,$lpc);      &parse_param($token,$lpc);
  }    } 
     }      }
     #reset parser  
       # Get set to take another pass through the XML:
       # for resources and links.
   
     $parser = HTML::TokeParser->new(\$instr);      $parser = HTML::TokeParser->new(\$instr);
     $parser->attr_encoded(1);      $parser->attr_encoded(1);
   
Line 160  sub loadmap { Line 235  sub loadmap {
   
     my $randomize = ($randomorder{$parent_rid} =~ /^yes$/i);      my $randomize = ($randomorder{$parent_rid} =~ /^yes$/i);
   
       # Parse the resources, link and condition tags.
       # Note that if randomorder or random select is chosen the links and
       # conditions are meaningless but are determined by the randomization.
       # This is handled in the next chunk of code.
   
     my @map_ids;      my @map_ids;
       my $codechecked;
       $rescount{$lpc} = 0;
       $mapcount{$lpc} = 0;
     while (my $token = $parser->get_token) {      while (my $token = $parser->get_token) {
  next if ($token->[0] ne 'S');   next if ($token->[0] ne 'S');
   
    # Resource
   
  if ($token->[1] eq 'resource') {   if ($token->[1] eq 'resource') {
     push(@map_ids,&parse_resource($token,$lpc,$ispage,$uri));      my $resource_id = &parse_resource($token,$lpc,$ispage,$uri,$courseid);
       if (defined $resource_id) {
    push(@map_ids, $resource_id);
                   if ($hash{'src_'.$lpc.'.'.$resource_id}) {
                       $rescount{$lpc} ++;
                       if (($hash{'src_'.$lpc.'.'.$resource_id}=~/\.sequence$/) || 
                           ($hash{'src_'.$lpc.'.'.$resource_id}=~/\.page$/)) {
                           $mapcount{$lpc} ++; 
                       }
                   }
                   unless ($codechecked) {
                       my $startsymb =
                          &Apache::lonnet::encode_symb($hash{'map_id_'.$lpc},$resource_id,
                                                       $hash{'src_'."$lpc.$resource_id"});
                       my $code = 
                           &Apache::lonnet::EXT('resource.0.examcode',$startsymb,undef,undef,
                                                undef,undef,$courseid);
                       if ($code) {
                           $randomizationcode{$parent_rid} = $code;
                       }
                       $codechecked = 1; 
                   }
       }
   
          # Link
   
  } elsif ($token->[1] eq 'link' && !$randomize) {   } elsif ($token->[1] eq 'link' && !$randomize) {
 # ----------------------------------------------------------------------- Links  
     &make_link(++$linkpc,$lpc,$token->[2]->{'to'},      &make_link(++$linkpc,$lpc,$token->[2]->{'to'},
        $token->[2]->{'from'},         $token->[2]->{'from'},
        $token->[2]->{'condition'});         $token->[2]->{'condition'}); # note ..condition may be undefined.
   
    # condition
   
  } elsif ($token->[1] eq 'condition' && !$randomize) {   } elsif ($token->[1] eq 'condition' && !$randomize) {
     &parse_condition($token,$lpc);      &parse_condition($token,$lpc);
  }   }
     }      }
       undef($codechecked);
   
       # Handle randomization and random selection
   
     if ($randomize) {      if ($randomize) {
  if (!$env{'request.role.adv'}) {          my $advanced;
           if ($env{'request.course.id'}) {
               $advanced = (&Apache::lonnet::allowed('adv') eq 'F');
           } else {
               $env{'request.course.id'} = $courseid;
               $advanced = (&Apache::lonnet::allowed('adv') eq 'F');
               $env{'request.course.id'} = '';
           }
           unless ($advanced) {
               # Order of resources is not randomized if user has and advanced role in the course.
     my $seed;      my $seed;
   
               # If the map's random seed parameter has been specified
               # it is used as the basis for computing the seed ...
   
     if (defined($randompickseed{$parent_rid})) {      if (defined($randompickseed{$parent_rid})) {
  $seed = $randompickseed{$parent_rid};   $seed = $randompickseed{$parent_rid};
     } else {      } else {
   
    # Otherwise the parent's fully encoded symb is used.
   
  my ($mapid,$resid)=split(/\./,$parent_rid);   my ($mapid,$resid)=split(/\./,$parent_rid);
  my $symb=   my $symb=
     &Apache::lonnet::encode_symb($hash{'map_id_'.$mapid},      &Apache::lonnet::encode_symb($hash{'map_id_'.$mapid},
Line 188  sub loadmap { Line 320  sub loadmap {
   
  $seed = $symb;   $seed = $symb;
     }      }
   
       # TODO: Here for sure we need to pass along the username/domain
       # so that we can impersonate users in lonprintout e.g.
   
               my $setcode;
               if (defined($randomizationcode{$parent_rid})) {
                   if ($env{'form.CODE'} eq '') {
                       $env{'form.CODE'} = $randomizationcode{$parent_rid};
                       $setcode = 1;
                   }
               }
   
     my $rndseed=&Apache::lonnet::rndseed($seed);      my $rndseed=&Apache::lonnet::rndseed($seed);
     &Apache::lonnet::setup_random_from_rndseed($rndseed);      &Apache::lonnet::setup_random_from_rndseed($rndseed);
   
               if ($setcode) {
                   undef($env{'form.CODE'});
                   undef($setcode);
               }
   
       # Take the set of map ids we have decoded and permute them to a
       # random order based on the seed set above. All of this is
       # processing the randomorder parameter if it is set, not
       # randompick.
   
     @map_ids=&Math::Random::random_permutation(@map_ids);      @map_ids=&Math::Random::random_permutation(@map_ids);
  }   }
   
  my $from = shift(@map_ids);   my $from = shift(@map_ids);
  my $from_rid = $lpc.'.'.$from;   my $from_rid = $lpc.'.'.$from;
  $hash{'map_start_'.$uri} = $from_rid;   $hash{'map_start_'.$uri} = $from_rid;
  $hash{'type_'.$from_rid}='start';   $hash{'type_'.$from_rid}='start';
   
    # Create links to reflect the random re-ordering done above.
    # In the code to process the map XML, we did not process links or conditions
    # if randomorder was set.  This means that for an instructor to choose
   
  while (my $to = shift(@map_ids)) {   while (my $to = shift(@map_ids)) {
     &make_link(++$linkpc,$lpc,$to,$from);      &make_link(++$linkpc,$lpc,$to,$from);
     my $to_rid =  $lpc.'.'.$to;      my $to_rid =  $lpc.'.'.$to;
Line 212  sub loadmap { Line 371  sub loadmap {
   
     $parser = HTML::TokeParser->new(\$instr);      $parser = HTML::TokeParser->new(\$instr);
     $parser->attr_encoded(1);      $parser->attr_encoded(1);
     # last parse out the mapalias params so as to ignore anything  
     # refering to non-existant resources      # last parse out the mapalias params.  These provide mnemonic
       # tags to resources that can be used in conditions
   
     while (my $token = $parser->get_token) {      while (my $token = $parser->get_token) {
  next if ($token->[0] ne 'S');   next if ($token->[0] ne 'S');
  if ($token->[1] eq 'param') {   if ($token->[1] eq 'param') {
Line 224  sub loadmap { Line 385  sub loadmap {
   
   
 # -------------------------------------------------------------------- Resource  # -------------------------------------------------------------------- Resource
   #
   #  Parses a resource tag to produce the value to push into the
   #  map_ids array.
   # 
   #
   #  Information about the actual type of resource is provided by the file extension
   #  of the uri (e.g. .problem, .sequence etc. etc.).
   #
   #  Parameters:
   #    $token   - A token from HTML::TokeParser
   #               This is an array that describes the most recently parsed HTML item.
   #    $lpc     - Map nesting level (?)
   #    $ispage  - True if this resource is encapsulated in a .page (assembled resourcde).
   #    $uri     - URI of the enclosing resource.
   #    $courseid - Course id of the course containing the resource being parsed. 
   # Returns:
   #   Value of the id attribute of the tag.
   #
   # Note:
   #   The token is an array that contains the following elements:
   #   [0]   => 'S' indicating this is a start token
   #   [1]   => 'resource'  indicating this tag is a <resource> tag.
   #   [2]   => Hash of attribute =>value pairs.
   #   [3]   => @(keys [2]).
   #   [4]   => unused.
   #
   #   The attributes of the resourcde tag include:
   #
   #   id     - The resource id.
   #   src    - The URI of the resource.
   #   type   - The resource type (e.g. start and finish).
   #   title  - The resource title.
   
   
 sub parse_resource {  sub parse_resource {
     my ($token,$lpc,$ispage,$uri) = @_;      my ($token,$lpc,$ispage,$uri,$courseid) = @_;
     if ($token->[2]->{'type'} eq 'zombie') { next; }      
     my $rid=$lpc.'.'.$token->[2]->{'id'};      # I refuse to countenance code like this that has 
       # such a dirty side effect (and forcing this sub to be called within a loop).
       #
       #  if ($token->[2]->{'type'} eq 'zombie') { next; }
       #
       #  The original code both returns _and_ skips to the next pass of the >caller's<
       #  loop, that's just dirty.
       #
   
       # Zombie resources don't produce anything useful.
   
       if ($token->[2]->{'type'} eq 'zombie') {
    return undef;
       }
   
       my $rid=$lpc.'.'.$token->[2]->{'id'}; # Resource id in hash is levelcounter.id-in-xml.
   
       # Save the hash element type and title:
           
     $hash{'kind_'.$rid}='res';      $hash{'kind_'.$rid}='res';
     $hash{'title_'.$rid}=$token->[2]->{'title'};      $hash{'title_'.$rid}=$token->[2]->{'title'};
   
       # Get the version free URI for the resource.
       # If a 'version' attribute was supplied, and this resource's version 
       # information has not yet been stored, store it.
       #
   
     my $turi=&versiontrack($token->[2]->{'src'});      my $turi=&versiontrack($token->[2]->{'src'});
     if ($token->[2]->{'version'}) {      if ($token->[2]->{'version'}) {
  unless ($hash{'version_'.$turi}) {   unless ($hash{'version_'.$turi}) {
     $hash{'version_'.$turi}=$1;      $hash{'version_'.$turi}=$1;
  }   }
     }      }
       # Pull out the title and do entity substitution on &colon
       # Q: Why no other entity substitutions?
   
     my $title=$token->[2]->{'title'};      my $title=$token->[2]->{'title'};
     $title=~s/\&colon\;/\:/gs;      $title=~s/\&colon\;/\:/gs;
 #   my $symb=&Apache::lonnet::encode_symb($uri,  
 #  $token->[2]->{'id'},  
 #  $turi);  
 #   &Apache::lonnet::do_cache_new('title',$symb,$title);      # I think the point of all this code is to construct a final
       # URI that apache and its rewrite rules can use to
       # fetch the resource.   Thi s sonly necessary if the resource
       # is not a page.  If the resource is a page then it must be
       # assembled (at fetch time?).
   
     unless ($ispage) {      unless ($ispage) {
  $turi=~/\.(\w+)$/;   $turi=~/\.(\w+)$/;
  my $embstyle=&Apache::loncommon::fileembstyle($1);   my $embstyle=&Apache::loncommon::fileembstyle($1);
Line 258  sub parse_resource { Line 484  sub parse_resource {
     } elsif ($turi!~/\.(sequence|page)$/) {      } elsif ($turi!~/\.(sequence|page)$/) {
  $turi='/adm/coursedocs/showdoc'.$turi;   $turi='/adm/coursedocs/showdoc'.$turi;
     }      }
           } elsif ($turi=~ m{^/adm/$match_domain/$match_courseid/\d+/ext\.tool$}) {
               $turi='/adm/wrapper'.$turi;
  } elsif ($turi=~/\S/) { # normal non-empty internal resource   } elsif ($turi=~/\S/) { # normal non-empty internal resource
     my $mapdir=$uri;      my $mapdir=$uri;
     $mapdir=~s/[^\/]+$//;      $mapdir=~s/[^\/]+$//;
Line 269  sub parse_resource { Line 497  sub parse_resource {
     }      }
  }   }
     }      }
 # Store reverse lookup, remove query string      # Store reverse lookup, remove query string resource 'ids'_uri => resource id.
       # If the URI appears more than one time in the sequence, it's resourcde
       # id's are constructed as a comma spearated list.
   
     my $idsuri=$turi;      my $idsuri=$turi;
     $idsuri=~s/\?.+$//;      $idsuri=~s/\?.+$//;
     if (defined($hash{'ids_'.$idsuri})) {      if (defined($hash{'ids_'.$idsuri})) {
Line 278  sub parse_resource { Line 509  sub parse_resource {
  $hash{'ids_'.$idsuri}=''.$rid;   $hash{'ids_'.$idsuri}=''.$rid;
     }      }
           
     if ($turi=~/\/(syllabus|aboutme|navmaps|smppg|bulletinboard)$/) {  
   
       if ($turi=~/\/(syllabus|aboutme|navmaps|smppg|bulletinboard|viewclasslist)$/) {
  $turi.='?register=1';   $turi.='?register=1';
     }      }
           
   
       # resource id lookup:  'src'_resourc-di  => URI decorated with a query
       # parameter as above if necessary due to the resource type.
       
     $hash{'src_'.$rid}=$turi;      $hash{'src_'.$rid}=$turi;
   
       # Mark the external-ness of the resource:
           
     if ($token->[2]->{'external'} eq 'true') {      if ($token->[2]->{'external'} eq 'true') {
  $hash{'ext_'.$rid}='true:';   $hash{'ext_'.$rid}='true:';
     } else {      } else {
  $hash{'ext_'.$rid}='false:';   $hash{'ext_'.$rid}='false:';
     }      }
   
       # If the resource is a start/finish resource set those
       # entries in the has so that navigation knows where everything starts.
       # TODO?  If there is a malformed sequence that has no start or no finish
       # resource, should this be detected and errors thrown?  How would such a 
       # resource come into being other than being manually constructed by a person
       # and then uploaded?  Could that happen if an author decided a sequence was almost
       # right edited it by hand and then reuploaded it to 'fix it' but accidently cut the
       #  start or finish resources?
       #
       #  All resourcess also get a type_id => (start | finish | normal)    hash entr.
       #
     if ($token->[2]->{'type'}) {      if ($token->[2]->{'type'}) {
  $hash{'type_'.$rid}=$token->[2]->{'type'};   $hash{'type_'.$rid}=$token->[2]->{'type'};
  if ($token->[2]->{'type'} eq 'start') {   if ($token->[2]->{'type'} eq 'start') {
Line 300  sub parse_resource { Line 551  sub parse_resource {
     }  else {      }  else {
  $hash{'type_'.$rid}='normal';   $hash{'type_'.$rid}='normal';
     }      }
   
       # Sequences end pages are constructed entities.  They require that the 
       # map that defines _them_ be loaded as well into the hash...with this resourcde
       # as the base of the nesting.
       # Resources like that are also marked with is_map_id => 1 entries.
       #
           
     if (($turi=~/\.sequence$/) ||      if (($turi=~/\.sequence$/) ||
  ($turi=~/\.page$/)) {   ($turi=~/\.page$/)) {
  $hash{'is_map_'.$rid}=1;   $hash{'is_map_'.$rid}=1;
  &loadmap($turi,$rid);   &loadmap($turi,$rid,$courseid);
     }       } 
     return $token->[2]->{'id'};      return $token->[2]->{'id'};
 }  }
   
   #-------------------------------------------------------------------- link
   #  Links define how you are allowed to move from one resource to another.
   #  They are the transition edges in the directed graph that a map is.
   #  This sub takes informatino from a <link> tag and constructs the
   #  navigation bits and pieces of a map.  There is no requirement that the
   #  resources that are linke are already defined, however clearly the map is 
   #  badly broken if they are not _eventually_ defined.
   #
   #  Note that links can be unconditional or conditional.
   #
   #  Parameters:
   #     linkpc   - The link counter for this level of map nesting (this is 
   #                reset to zero by loadmap prior to starting to process
   #                links for map).
   #     lpc      - The map level ocounter (how deeply nested this map is in
   #                the hierarchy of maps that are recursively read in.
   #     to       - resource id (within the XML) of the target of the edge.
   #     from     - resource id (within the XML) of the source of the edge.
   #     condition- id of condition associated with the edge (also within the XML).
   #
   
 sub make_link {  sub make_link {
     my ($linkpc,$lpc,$to,$from,$condition) = @_;      my ($linkpc,$lpc,$to,$from,$condition) = @_;
           
       #  Compute fully qualified ids for the link, the 
       # and from/to by prepending lpc.
       #
   
     my $linkid=$lpc.'.'.$linkpc;      my $linkid=$lpc.'.'.$linkpc;
     my $goesto=$lpc.'.'.$to;      my $goesto=$lpc.'.'.$to;
     my $comesfrom=$lpc.'.'.$from;      my $comesfrom=$lpc.'.'.$from;
     my $undercond=0;      my $undercond=0;
   
   
       # If there is a condition, qualify it with the level counter.
   
     if ($condition) {      if ($condition) {
  $undercond=$lpc.'.'.$condition;   $undercond=$lpc.'.'.$condition;
     }      }
   
       # Links are represnted by:
       #  goesto_.fuullyqualifedlinkid => fully qualified to
       #  comesfrom.fullyqualifiedlinkid => fully qualified from
       #  undercond_.fullyqualifiedlinkid => fully qualified condition id.
   
     $hash{'goesto_'.$linkid}=$goesto;      $hash{'goesto_'.$linkid}=$goesto;
     $hash{'comesfrom_'.$linkid}=$comesfrom;      $hash{'comesfrom_'.$linkid}=$comesfrom;
     $hash{'undercond_'.$linkid}=$undercond;      $hash{'undercond_'.$linkid}=$undercond;
   
       # In addition:
       #   to_.fully qualified from => comma separated list of 
       #   link ids with that from.
       # Similarly:
       #   from_.fully qualified to => comma separated list of link ids`
       #                               with that to.
       #  That allows us given a resource id to know all edges that go to it
       #  and leave from it.
       #
   
     if (defined($hash{'to_'.$comesfrom})) {      if (defined($hash{'to_'.$comesfrom})) {
  $hash{'to_'.$comesfrom}.=','.$linkid;   $hash{'to_'.$comesfrom}.=','.$linkid;
     } else {      } else {
Line 338  sub make_link { Line 638  sub make_link {
 }  }
   
 # ------------------------------------------------------------------- Condition  # ------------------------------------------------------------------- Condition
   #
   #  Processes <condition> tags, storing sufficient information about them
   #  in the hash so that they can be evaluated and used to conditionalize
   #  what is presented to the student.
   #
   #  these can have the following attributes 
   #
   #    id    = A unique identifier of the condition within the map.
   #
   #    value = Is a perl script-let that, when evaluated in safe space
   #            determines whether or not the condition is true.
   #            Normally this takes the form of a test on an  Apache::lonnet::EXT call
   #            to find the value of variable associated with a resource in the
   #            map identified by a mapalias.
   #            Here's a fragment of XML code that illustrates this:
   #
   #           <param to="5" value="mainproblem" name="parameter_0_mapalias" type="string" />
   #           <resource src="" id="1" type="start" title="Start" />
   #           <resource src="/res/msu/albertel/b_and_c/p1.problem" id="5"  title="p1.problem" />
   #           <condition value="&EXT('user.resource.resource.0.tries','mainproblem')
   #           <2 " id="61" type="stop" />
   #           <link to="5" index="1" from="1" condition="61" />    
   #
   #           In this fragment:
   #             - The param tag establishes an alias to resource id 5 of 'mainproblem'.
   #             - The resource that is the start of the map is identified.
   #             - The resource tag identifies the resource associated with this tag
   #               and gives it the id 5.
   #             - The condition is true if the tries variable associated with mainproblem
   #               is less than 2 (that is the user has had more than 2 tries).
   #               The condition type is a stop condition which inhibits(?) the associated
   #               link if the condition  is false. 
   #             - The link to resource 5 from resource 1 is affected by this condition.    
   #            
   #    type  = Type of the condition. The type determines how the condition affects the
   #            link associated with it and is one of
   #            -  'force'
   #            -  'stop'
   #              anything else including not supplied..which treated as:
   #            - 'normal'.
   #            Presumably maps get created by the resource assembly tool and therefore
   #            illegal type values won't squirm their way into the XML.
   #
   # Side effects:
   #   -  The kind_level-qualified-condition-id hash element is set to 'cond'.
   #   -  The condition text is pushed into the cond array and its element number is
   #      set in the condid_level-qualified-condition-id element of the hash.
   #   - The condition type is colon appneded to the cond array element for this condition.
 sub parse_condition {  sub parse_condition {
     my ($token,$lpc) = @_;      my ($token,$lpc) = @_;
     my $rid=$lpc.'.'.$token->[2]->{'id'};      my $rid=$lpc.'.'.$token->[2]->{'id'};
Line 356  sub parse_condition { Line 704  sub parse_condition {
 }  }
   
 # ------------------------------------------------------------------- Parameter  # ------------------------------------------------------------------- Parameter
   # Parse a <parameter> tag in the map.
   # Parmameters:
   #    $token Token array for a start tag from HTML::TokeParser
   #           [0] = 'S'
   #           [1] = tagname ("param")
   #           [2] = Hash of {attribute} = values.
   #           [3] = Array of the keys in [2].
   #           [4] = unused.
   #    $lpc   Current map nesting level.a
   #
   #  Typical attributes:
   #     to=n      - Number of the resource the parameter applies to.
   #     type=xx   - Type of parameter value (e.g. string_yesno or int_pos).
   #     name=xxx  - Name of parameter (e.g. parameter_randompick or parameter_randomorder).
   #     value=xxx - value of the parameter.
   
 sub parse_param {  sub parse_param {
     my ($token,$lpc) = @_;      my ($token,$lpc) = @_;
     my $referid=$lpc.'.'.$token->[2]->{'to'};      my $referid=$lpc.'.'.$token->[2]->{'to'}; # Resource param applies to.
     my $name=$token->[2]->{'name'};      my $name=$token->[2]->{'name'};      # Name of parameter
     my $part;      my $part;
     if ($name=~/^parameter_(.*)_/) {  
   
       if ($name=~/^parameter_(.*)_/) { 
  $part=$1;   $part=$1;
     } else {      } else {
  $part=0;   $part=0;
     }      }
   
       # Peel the parameter_ off the parameter name.
   
     $name=~s/^.*_([^_]*)$/$1/;      $name=~s/^.*_([^_]*)$/$1/;
   
       # The value is:
       #   type.part.name.value
   
     my $newparam=      my $newparam=
  &escape($token->[2]->{'type'}).':'.   &escape($token->[2]->{'type'}).':'.
  &escape($part.'.'.$name).'='.   &escape($part.'.'.$name).'='.
  &escape($token->[2]->{'value'});   &escape($token->[2]->{'value'});
   
       # The hash key is param_resourceid.
       # Multiple parameters for a single resource are & separated in the hash.
   
   
     if (defined($hash{'param_'.$referid})) {      if (defined($hash{'param_'.$referid})) {
  $hash{'param_'.$referid}.='&'.$newparam;   $hash{'param_'.$referid}.='&'.$newparam;
     } else {      } else {
  $hash{'param_'.$referid}=''.$newparam;   $hash{'param_'.$referid}=''.$newparam;
     }      }
     if ($token->[2]->{'name'}=~/^parameter_(0_)*randompick$/) {      #
       #  These parameters have to do with randomly selecting
       # resources, therefore a separate hash is also created to 
       # make it easy to locate them when actually computing the resource set later on
       # See the code conditionalized by ($randomize) in loadmap().
   
       if ($token->[2]->{'name'}=~/^parameter_(0_)*randompick$/) { # Random selection turned on
  $randompick{$referid}=$token->[2]->{'value'};   $randompick{$referid}=$token->[2]->{'value'};
     }      }
     if ($token->[2]->{'name'}=~/^parameter_(0_)*randompickseed$/) {      if ($token->[2]->{'name'}=~/^parameter_(0_)*randompickseed$/) { # Randomseed provided.
  $randompickseed{$referid}=$token->[2]->{'value'};   $randompickseed{$referid}=$token->[2]->{'value'};
     }      }
     if ($token->[2]->{'name'}=~/^parameter_(0_)*randomorder$/) {      if ($token->[2]->{'name'}=~/^parameter_(0_)*randomorder$/) { # Random order turned on.
  $randomorder{$referid}=$token->[2]->{'value'};   $randomorder{$referid}=$token->[2]->{'value'};
     }      }
   
       # These parameters have to do with how the URLs of resources are presented to
       # course members(?).  encrypturl presents encypted url's while
       # hiddenresource hides the URL.
       #
   
     if ($token->[2]->{'name'}=~/^parameter_(0_)*encrypturl$/) {      if ($token->[2]->{'name'}=~/^parameter_(0_)*encrypturl$/) {
  if ($token->[2]->{'value'}=~/^yes$/i) {   if ($token->[2]->{'value'}=~/^yes$/i) {
     $encurl{$referid}=1;      $encurl{$referid}=1;
Line 397  sub parse_param { Line 786  sub parse_param {
  }   }
     }      }
 }  }
   #
   #  Parse mapalias parameters.
   #  these are tags of the form:
   #  <param to="nn" 
   #         value="some-alias-for-resourceid-nn" 
   #         name="parameter_0_mapalias" 
   #         type="string" />
   #  A map alias is a textual name for a resource:
   #    - The to  attribute identifies the resource (this gets level qualified below)
   #    - The value attributes provides the alias string.
   #    - name must be of the regexp form: /^parameter_(0_)*mapalias$/
   #    - e.g. the string 'parameter_' followed by 0 or more "0_" strings
   #      terminating with the string 'mapalias'.
   #      Examples:
   #         'parameter_mapalias', 'parameter_0_mapalias', parameter_0_0_mapalias'
   #  Invalid to ids are silently ignored.
   #
   #  Parameters:
   #     token - The token array fromthe HMTML::TokeParser
   #     lpc   - The current map level counter.
   #
 sub parse_mapalias_param {  sub parse_mapalias_param {
     my ($token,$lpc) = @_;      my ($token,$lpc) = @_;
   
       # Fully qualify the to value and ignore the alias if there is no
       # corresponding resource.
   
     my $referid=$lpc.'.'.$token->[2]->{'to'};      my $referid=$lpc.'.'.$token->[2]->{'to'};
     return if (!exists($hash{'src_'.$referid}));      return if (!exists($hash{'src_'.$referid}));
   
       # If this is a valid mapalias parameter, 
       # Append the target id to the count_mapalias element for that
       # alias so that we can detect doubly defined aliases
       # e.g.:
       #  <param to="1" value="george" name="parameter_0_mapalias" type="string" />
       #  <param to="2" value="george" name="parameter_0_mapalias" type="string" />
       #
       #  The example above is trivial but the case that's important has to do with
       #  constructing a map that includes a nested map where the nested map may have
       #  aliases that conflict with aliases established in the enclosing map.
       #
       # ...and create/update the hash mapalias entry to actually store the alias.
       #
   
     if ($token->[2]->{'name'}=~/^parameter_(0_)*mapalias$/) {      if ($token->[2]->{'name'}=~/^parameter_(0_)*mapalias$/) {
  &count_mapalias($token->[2]->{'value'},$referid);   &count_mapalias($token->[2]->{'value'},$referid);
  $hash{'mapalias_'.$token->[2]->{'value'}}=$referid;   $hash{'mapalias_'.$token->[2]->{'value'}}=$referid;
Line 411  sub parse_mapalias_param { Line 838  sub parse_mapalias_param {
   
 # --------------------------------------------------------- Simplify expression  # --------------------------------------------------------- Simplify expression
   
   
   #
   #  Someone should really comment this to describe what it does to what and why.
   #
 sub simplify {  sub simplify {
     my $expression=shift;      my $expression=shift;
 # (0&1) = 1  # (0&1) = 1
Line 420  sub simplify { Line 851  sub simplify {
 # 8&8=8  # 8&8=8
     $expression=~s/([^_\.\d])([_\.\d]+)\&\2([^_\.\d])/$1$2$3/g;      $expression=~s/([^_\.\d])([_\.\d]+)\&\2([^_\.\d])/$1$2$3/g;
 # 8|8=8  # 8|8=8
     $expression=~s/([^_\.\d])([_\.\d]+)\|\2([^_\.\d])/$1$2$3/g;      $expression=~s/([^_\.\d])([_\.\d]+)(?:\|\2)+([^_\.\d])/$1$2$3/g;
 # (5&3)&4=5&3&4  # (5&3)&4=5&3&4
     $expression=~s/\(([_\.\d]+)((?:\&[_\.\d]+)+)\)\&([_\.\d]+[^_\.\d])/$1$2\&$3/g;      $expression=~s/\(([_\.\d]+)((?:\&[_\.\d]+)+)\)\&([_\.\d]+[^_\.\d])/$1$2\&$3/g;
 # (((5&3)|(4&6)))=((5&3)|(4&6))  # (((5&3)|(4&6)))=((5&3)|(4&6))
Line 434  sub simplify { Line 865  sub simplify {
   
 # -------------------------------------------------------- Build condition hash  # -------------------------------------------------------- Build condition hash
   
   #
   #  Traces a route recursively through the map after it has been loaded
   #  (I believe this really visits each resourcde that is reachable fromt he
   #  start top node.
   #
   #  - Marks hidden resources as hidden.
   #  - Marks which resource URL's must be encrypted.
   #  - Figures out (if necessary) the first resource in the map.
   #  - Further builds the chunks of the big hash that define how 
   #    conditions work
   #
   #  Note that the tracing strategy won't visit resources that are not linked to
   #  anything or islands in the map (groups of resources that form a path but are not
   #  linked in to the path that can be traced from the start resource...but that's ok
   #  because by definition, those resources are not reachable by users of the course.
   #
   # Parameters:
   #   sofar    - _URI of the prior entry or 0 if this is the top.
   #   rid      - URI of the resource to visit.
   #   beenhere - list of resources (each resource enclosed by &'s) that have
   #              already been visited.
   #   encflag  - If true the resource that resulted in a recursive call to us
   #              has an encoded URL (which means contained resources should too). 
   #   hdnflag  - If true,the resource that resulted in a recursive call to us
   #              was hidden (which means contained resources should be hidden too).
   # Returns
   #    new value indicating how far the map has been traversed (the sofar).
   #
 sub traceroute {  sub traceroute {
     my ($sofar,$rid,$beenhere,$encflag,$hdnflag)=@_;      my ($sofar,$rid,$beenhere,$encflag,$hdnflag)=@_;
     my $newsofar=$sofar=simplify($sofar);      my $newsofar=$sofar=simplify($sofar);
   
     unless ($beenhere=~/\&\Q$rid\E\&/) {      unless ($beenhere=~/\&\Q$rid\E\&/) {
  $beenhere.=$rid.'&';     $beenhere.=$rid.'&';  
  my ($mapid,$resid)=split(/\./,$rid);   my ($mapid,$resid)=split(/\./,$rid);
Line 452  sub traceroute { Line 912  sub traceroute {
   
  my $encrypt=&Apache::lonnet::EXT('resource.0.encrypturl',$symb);   my $encrypt=&Apache::lonnet::EXT('resource.0.encrypturl',$symb);
  if ($encflag || lc($encrypt) eq 'yes') { $encurl{$rid}=1; }   if ($encflag || lc($encrypt) eq 'yes') { $encurl{$rid}=1; }
   
  if (($retfrid eq '') && ($hash{'src_'.$rid})   if (($retfrid eq '') && ($hash{'src_'.$rid})
     && ($hash{'src_'.$rid}!~/\.sequence$/)) {      && ($hash{'src_'.$rid}!~/\.sequence$/)) {
     $retfrid=$rid;      $retfrid=$rid;
  }   }
   
  if (defined($hash{'conditions_'.$rid})) {   if (defined($hash{'conditions_'.$rid})) {
     $hash{'conditions_'.$rid}=simplify(      $hash{'conditions_'.$rid}=simplify(
            '('.$hash{'conditions_'.$rid}.')|('.$sofar.')');             '('.$hash{'conditions_'.$rid}.')|('.$sofar.')');
Line 465  sub traceroute { Line 927  sub traceroute {
   
  # if the expression is just the 0th condition keep it   # if the expression is just the 0th condition keep it
  # otherwise leave a pointer to this condition expression   # otherwise leave a pointer to this condition expression
   
  $newsofar = ($sofar eq '0') ? $sofar : '_'.$rid;   $newsofar = ($sofar eq '0') ? $sofar : '_'.$rid;
   
    # Recurse if the resource is a map:
   
  if (defined($hash{'is_map_'.$rid})) {   if (defined($hash{'is_map_'.$rid})) {
     if (defined($hash{'map_start_'.$hash{'src_'.$rid}})) {      if (defined($hash{'map_start_'.$hash{'src_'.$rid}})) {
  $sofar=$newsofar=   $sofar=$newsofar=
Line 477  sub traceroute { Line 942  sub traceroute {
  $hdnflag || $hiddenurl{$rid});   $hdnflag || $hiddenurl{$rid});
     }      }
  }   }
   
    # Processes  links to this resource:
    #  - verify the existence of any conditionals on the link to here.
    #  - Recurse to any resources linked to us.
    #
  if (defined($hash{'to_'.$rid})) {   if (defined($hash{'to_'.$rid})) {
     foreach my $id (split(/\,/,$hash{'to_'.$rid})) {      foreach my $id (split(/\,/,$hash{'to_'.$rid})) {
  my $further=$sofar;   my $further=$sofar;
    #
    # If there's a condition associated with this link be sure
    # it's been defined else that's an error:
    #
                 if ($hash{'undercond_'.$id}) {                  if ($hash{'undercond_'.$id}) {
     if (defined($hash{'condid_'.$hash{'undercond_'.$id}})) {      if (defined($hash{'condid_'.$hash{'undercond_'.$id}})) {
  $further=simplify('('.'_'.$rid.')&('.   $further=simplify('('.'_'.$rid.')&('.
   $hash{'condid_'.$hash{'undercond_'.$id}}.')');    $hash{'condid_'.$hash{'undercond_'.$id}}.')');
     } else {      } else {
  $errtext.=&mt('<br />Undefined condition ID: [_1]',$hash{'undercond_'.$id});   $errtext.= '<br />'.
                                      &mt('Undefined condition ID: [_1]',
                                          $hash{'undercond_'.$id});
     }      }
                 }                  }
    #  Recurse to resoruces that have to's to us.
                 $newsofar=&traceroute($further,$hash{'goesto_'.$id},$beenhere,                  $newsofar=&traceroute($further,$hash{'goesto_'.$id},$beenhere,
       $encflag,$hdnflag);        $encflag,$hdnflag);
     }      }
Line 498  sub traceroute { Line 975  sub traceroute {
   
 # ------------------------------ Cascading conditions, quick access, parameters  # ------------------------------ Cascading conditions, quick access, parameters
   
   #
   #  Seems a rather strangely named sub given what the comment above says it does.
   
   
 sub accinit {  sub accinit {
     my ($uri,$short,$fn)=@_;      my ($uri,$short,$fn)=@_;
     my %acchash=();      my %acchash=();
     my %captured=();      my %captured=();
     my $condcounter=0;      my $condcounter=0;
     $acchash{'acc.cond.'.$short.'.0'}=0;      $acchash{'acc.cond.'.$short.'.0'}=0;
   
       # This loop is only interested in conditions and 
       # parameters in the big hash:
   
     foreach my $key (keys(%hash)) {      foreach my $key (keys(%hash)) {
   
    # conditions:
   
  if ($key=~/^conditions/) {   if ($key=~/^conditions/) {
     my $expr=$hash{$key};      my $expr=$hash{$key};
   
     # try to find and factor out common sub-expressions      # try to find and factor out common sub-expressions
       # Any subexpression that is found is simplified, removed from
       # the original condition expression and the simplified sub-expression
       # substituted back in to the epxression..I'm not actually convinced this
       # factors anything out...but instead maybe simplifies common factors(?)
   
     foreach my $sub ($expr=~m/(\(\([_\.\d]+(?:\&[_\.\d]+)+\)(?:\|\([_\.\d]+(?:\&[_\.\d]+)+\))+\))/g) {      foreach my $sub ($expr=~m/(\(\([_\.\d]+(?:\&[_\.\d]+)+\)(?:\|\([_\.\d]+(?:\&[_\.\d]+)+\))+\))/g) {
  my $orig=$sub;   my $orig=$sub;
   
Line 521  sub accinit { Line 1015  sub accinit {
  $expr=~s/\Q$orig\E/$sub/;   $expr=~s/\Q$orig\E/$sub/;
     }      }
     $hash{$key}=$expr;      $hash{$key}=$expr;
   
              # If not yet seen, record in acchash and that we've seen it.
   
     unless (defined($captured{$expr})) {      unless (defined($captured{$expr})) {
  $condcounter++;   $condcounter++;
  $captured{$expr}=$condcounter;   $captured{$expr}=$condcounter;
  $acchash{'acc.cond.'.$short.'.'.$condcounter}=$expr;   $acchash{'acc.cond.'.$short.'.'.$condcounter}=$expr;
     }       } 
           # Parameters:
   
  } elsif ($key=~/^param_(\d+)\.(\d+)/) {   } elsif ($key=~/^param_(\d+)\.(\d+)/) {
     my $prefix=&Apache::lonnet::encode_symb($hash{'map_id_'.$1},$2,      my $prefix=&Apache::lonnet::encode_symb($hash{'map_id_'.$1},$2,
     $hash{'src_'.$1.'.'.$2});      $hash{'src_'.$1.'.'.$2});
Line 539  sub accinit { Line 1038  sub accinit {
     }      }
  }   }
     }      }
       # This loop only processes id entries in the big hash.
   
     foreach my $key (keys(%hash)) {      foreach my $key (keys(%hash)) {
  if ($key=~/^ids/) {   if ($key=~/^ids/) {
     foreach my $resid (split(/\,/,$hash{$key})) {      foreach my $resid (split(/\,/,$hash{$key})) {
Line 582  sub accinit { Line 1083  sub accinit {
   
 sub hiddenurls {  sub hiddenurls {
     my $randomoutentry='';      my $randomoutentry='';
     foreach my $rid (keys %randompick) {      foreach my $rid (keys(%randompick)) {
         my $rndpick=$randompick{$rid};          my $rndpick=$randompick{$rid};
         my $mpc=$hash{'map_pc_'.$hash{'src_'.$rid}};          my $mpc=$hash{'map_pc_'.$hash{'src_'.$rid}};
 # ------------------------------------------- put existing resources into array  # ------------------------------------------- put existing resources into array
Line 603  sub hiddenurls { Line 1104  sub hiddenurls {
 # -------------------------------- randomly eliminate the ones that should stay  # -------------------------------- randomly eliminate the ones that should stay
  my (undef,$id)=split(/\./,$rid);   my (undef,$id)=split(/\./,$rid);
         if ($randompickseed{$rid}) { $id=$randompickseed{$rid}; }          if ($randompickseed{$rid}) { $id=$randompickseed{$rid}; }
           my $setcode;
           if (defined($randomizationcode{$rid})) {
               if ($env{'form.CODE'} eq '') {
                   $env{'form.CODE'} = $randomizationcode{$rid};
                   $setcode = 1;
               }
           }
  my $rndseed=&Apache::lonnet::rndseed($id); # use id instead of symb   my $rndseed=&Apache::lonnet::rndseed($id); # use id instead of symb
           if ($setcode) {
               undef($env{'form.CODE'});
               undef($setcode);
           }
  &Apache::lonnet::setup_random_from_rndseed($rndseed);   &Apache::lonnet::setup_random_from_rndseed($rndseed);
  my @whichids=&Math::Random::random_permuted_index($#currentrids+1);   my @whichids=&Math::Random::random_permuted_index($#currentrids+1);
         for (my $i=1;$i<=$rndpick;$i++) { $currentrids[$whichids[$i]]=''; }          for (my $i=1;$i<=$rndpick;$i++) { $currentrids[$whichids[$i]]=''; }
Line 613  sub hiddenurls { Line 1125  sub hiddenurls {
             if ($currentrids[$k]) {              if ($currentrids[$k]) {
  $hash{'randomout_'.$currentrids[$k]}=1;   $hash{'randomout_'.$currentrids[$k]}=1;
                 my ($mapid,$resid)=split(/\./,$currentrids[$k]);                  my ($mapid,$resid)=split(/\./,$currentrids[$k]);
                   if ($rescount{$mapid}) {
                       $rescount{$mapid} --;
                   }
                   if ($hash{'is_map_'.$currentrids[$k]}) {
                       if ($mapcount{$mapid}) {
                           $mapcount{$mapid} --;
                       }
                   }
                 $randomoutentry.='&'.                  $randomoutentry.='&'.
     &Apache::lonnet::encode_symb($hash{'map_id_'.$mapid},      &Apache::lonnet::encode_symb($hash{'map_id_'.$mapid},
  $resid,   $resid,
Line 622  sub hiddenurls { Line 1142  sub hiddenurls {
         }          }
     }      }
 # ------------------------------ take care of explicitly hidden urls or folders  # ------------------------------ take care of explicitly hidden urls or folders
     foreach my $rid (keys %hiddenurl) {      foreach my $rid (keys(%hiddenurl)) {
  $hash{'randomout_'.$rid}=1;   $hash{'randomout_'.$rid}=1;
  my ($mapid,$resid)=split(/\./,$rid);   my ($mapid,$resid)=split(/\./,$rid);
           if ($rescount{$mapid}) {
               $rescount{$mapid} --;
           }
           if ($hash{'is_map_'.$rid}) {
               if ($mapcount{$mapid}) {
                   $mapcount{$mapid} --;
               }
           }
  $randomoutentry.='&'.   $randomoutentry.='&'.
     &Apache::lonnet::encode_symb($hash{'map_id_'.$mapid},$resid,      &Apache::lonnet::encode_symb($hash{'map_id_'.$mapid},$resid,
  $hash{'src_'.$rid}).'&';   $hash{'src_'.$rid}).'&';
Line 635  sub hiddenurls { Line 1163  sub hiddenurls {
     }      }
 }  }
   
   # -------------------------------------- populate big hash with map breadcrumbs
   
   # Create map_breadcrumbs_$pc from map_hierarchy_$pc by omitting intermediate
   # maps not shown in Course Contents table.
   
   sub mapcrumbs {
       foreach my $key (keys(%rescount)) {
           if ($hash{'map_hierarchy_'.$key}) {
               my $skipnext = 0;
               foreach my $id (split(/,/,$hash{'map_hierarchy_'.$key}),$key) {
                   unless ($skipnext) {
                       $hash{'map_breadcrumbs_'.$key} .= "$id,";
                   }
                   unless (($id == 0) || ($id == 1)) {
                       if ((!$rescount{$id}) || ($rescount{$id} == 1 && $mapcount{$id} == 1)) {
                           $skipnext = 1;
                       } else {
                           $skipnext = 0;
                       }
                   }
               }
               $hash{'map_breadcrumbs_'.$key} =~ s/,$//;
           }
       }
   }
   
 # ---------------------------------------------------- Read map and all submaps  # ---------------------------------------------------- Read map and all submaps
   
 sub readmap {  sub readmap {
     my $short=shift;      my $short=shift;
     $short=~s/^\///;      $short=~s/^\///;
     my %cenv=&Apache::lonnet::coursedescription($short,{'freshen_cache'=>1});  
       # TODO:  Hidden dependency on current user:
   
       my %cenv=&Apache::lonnet::coursedescription($short,{'freshen_cache'=>1}); 
   
     my $fn=$cenv{'fn'};      my $fn=$cenv{'fn'};
     my $uri;      my $uri;
     $short=~s/\//\_/g;      $short=~s/\//\_/g;
     unless ($uri=$cenv{'url'}) {       unless ($uri=$cenv{'url'}) { 
  &Apache::lonnet::logthis("<font color=blue>WARNING: ".   &Apache::lonnet::logthis('<font color="blue">WARNING: '.
  "Could not load course $short.</font>");    "Could not load course $short.</font>"); 
  return ('',&mt('No course data available.'));;   return ('',&mt('No course data available.'));;
     }      }
     @cond=('true:normal');      @cond=('true:normal');
   
     open(LOCKFILE,">$fn.db.lock");      unless (open(LOCKFILE,">$fn.db.lock")) {
    # 
    # Most likely a permissions problem on the lockfile or its directory.
    #
           $retfurl = '';
           return ($retfurl,'<br />'.&mt('Map not loaded - Lock file could not be opened when reading map:').' <tt>'.$fn.'</tt>.');
       }
     my $lock=0;      my $lock=0;
     my $gotstate=0;      my $gotstate=0;
     if (flock(LOCKFILE,LOCK_EX|LOCK_NB)) {      
  $lock=1;      # If we can get the lock without delay any files there are idle
       # and from some prior request.  We'll kill them off and regenerate them:
   
       if (flock(LOCKFILE,LOCK_EX|LOCK_NB)) {
    $lock=1; # Remember that we hold the lock.
         &unlink_tmpfiles($fn);          &unlink_tmpfiles($fn);
     }      }
     undef %randompick;      undef %randompick;
     undef %hiddenurl;      undef %hiddenurl;
     undef %encurl;      undef %encurl;
     $retfrid='';      $retfrid='';
     my ($untiedhash,$untiedparmhash,$tiedhash,$tiedparmhash);      $errtext='';
       my ($untiedhash,$untiedparmhash,$tiedhash,$tiedparmhash); # More state flags.
   
       # if we got the lock, regenerate course regnerate empty files and tie them.
   
     if ($lock) {      if ($lock) {
         if (tie(%hash,'GDBM_File',"$fn.db",&GDBM_WRCREAT(),0640)) {          if (tie(%hash,'GDBM_File',"$fn.db",&GDBM_WRCREAT(),0640)) {
             $tiedhash = 1;              $tiedhash = 1;
             if (tie(%parmhash,'GDBM_File',$fn.'_parms.db',&GDBM_WRCREAT(),0640)) {              if (tie(%parmhash,'GDBM_File',$fn.'_parms.db',&GDBM_WRCREAT(),0640)) {
                 $tiedparmhash = 1;                  $tiedparmhash = 1;
                 $gotstate = &build_tmp_hashes($uri,$fn,$short,\%cenv);                  $gotstate = &build_tmp_hashes($uri,
         $fn,
         $short,
         \%cenv); # TODO: Need to provide requested user@dom
                 unless ($gotstate) {                  unless ($gotstate) {
                     &Apache::lonnet::logthis('Failed to write statemap at first attempt '.$fn.' for '.$uri.'.</font>');                      &Apache::lonnet::logthis('Failed to write statemap at first attempt '.$fn.' for '.$uri.'.</font>');
                 }                  }
Line 684  sub readmap { Line 1259  sub readmap {
                     'Could not untie coursemap hash '.$fn.' for '.$uri.'.</font>');                      'Could not untie coursemap hash '.$fn.' for '.$uri.'.</font>');
             }              }
         }          }
  flock(LOCKFILE,LOCK_UN);   flock(LOCKFILE,LOCK_UN); # RF: this is what I don't get unless there are other
  close(LOCKFILE);                           # unlocked places the remainder happens..seems like if we
                                    # just kept the lock here the rest of the code would have
                                    # been much easier? 
     }      }
     unless ($lock && $tiedhash && $tiedparmhash) {       unless ($lock && $tiedhash && $tiedparmhash) { 
  # if we are here it is likely because we are already trying to    # if we are here it is likely because we are already trying to 
Line 693  sub readmap { Line 1270  sub readmap {
  # tie the hashes for the next 90 seconds, if we succeed forward    # 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    # them on to navmaps, if we fail, throw up the Could not init 
  # course screen   # course screen
    #
    # RF: I'm not seeing the case where the ties/unties can fail in a way
    #     that can be remedied by this.  Since we owned the lock seems
    #     Tie/untie failures are a result of something like a permissions problem instead?
    #
   
    #  In any vent, undo what we did manage to do above first:
  if ($lock) {   if ($lock) {
     # Got the lock but not the DB files      # Got the lock but not the DB files
     flock(LOCKFILE,LOCK_UN);      flock(LOCKFILE,LOCK_UN);
Line 708  sub readmap { Line 1292  sub readmap {
                 untie(%parmhash);                  untie(%parmhash);
             }              }
         }          }
  &Apache::lonnet::logthis("<font color=blue>WARNING: ".   # Log our failure:
   
    &Apache::lonnet::logthis('<font color="blue">WARNING: '.
  "Could not tie coursemap $fn for $uri.</font>");   "Could not tie coursemap $fn for $uri.</font>");
         $tiedhash = '';          $tiedhash = '';
         $tiedparmhash = '';          $tiedparmhash = '';
  my $i=0;   my $i=0;
   
    # Keep on retrying the lock for 90 sec until we succeed.
   
  while($i<90) {   while($i<90) {
     $i++;      $i++;
     sleep(1);      sleep(1);
     if (flock(LOCKFILE,LOCK_EX|LOCK_NB)) {      if (flock(LOCKFILE,LOCK_EX|LOCK_NB)) {
   
    # Got the lock, tie the hashes...the assumption in this code is
    # that some other worker thread has created the db files quite recently
    # so no load is needed:
   
                 $lock = 1;                  $lock = 1;
  if (tie(%hash,'GDBM_File',"$fn.db",&GDBM_READER(),0640)) {   if (tie(%hash,'GDBM_File',"$fn.db",&GDBM_READER(),0640)) {
                     $tiedhash = 1;                      $tiedhash = 1;
Line 724  sub readmap { Line 1318  sub readmap {
                         $tiedparmhash = 1;                          $tiedparmhash = 1;
                         if (-e "$fn.state") {                          if (-e "$fn.state") {
             $retfurl='/adm/navmaps';              $retfurl='/adm/navmaps';
   
       # BUG BUG: Side effect!
       # Should conditionalize on something so that we can use this
       # to load maps for courses that are not current?
       #
             &Apache::lonnet::appenv({"request.course.id"  => $short,              &Apache::lonnet::appenv({"request.course.id"  => $short,
                "request.course.fn"  => $fn,                 "request.course.fn"  => $fn,
              "request.course.uri" => $uri});               "request.course.uri" => $uri,
                                                        "request.course.tied" => time});
                               
             $untiedhash = untie(%hash);              $untiedhash = untie(%hash);
             $untiedparmhash = untie(%parmhash);              $untiedparmhash = untie(%parmhash);
                             $gotstate = 1;                              $gotstate = 1;
Line 740  sub readmap { Line 1341  sub readmap {
  }   }
         if ($lock) {          if ($lock) {
             flock(LOCKFILE,LOCK_UN);              flock(LOCKFILE,LOCK_UN);
               $lock = 0;
             if ($tiedparmhash) {              if ($tiedparmhash) {
                 unless ($untiedparmhash) {                  unless ($untiedparmhash) {
                     &Apache::lonnet::logthis('<font color="blue">WARNING: '.                      &Apache::lonnet::logthis('<font color="blue">WARNING: '.
Line 754  sub readmap { Line 1356  sub readmap {
             }              }
         }          }
     }      }
       # I think this branch of code is all about what happens if we just did the stuff above, 
       # but found that the  state file did not exist...again if we'd just held the lock
       # would that have made this logic simpler..as generating all the files would be
       # an atomic operation with respect to the lock.
       #
     unless ($gotstate) {      unless ($gotstate) {
           $lock = 0;
         &Apache::lonnet::logthis('<font color="blue">WARNING: '.          &Apache::lonnet::logthis('<font color="blue">WARNING: '.
                      'Could not read statemap '.$fn.' for '.$uri.'.</font>');                       'Could not read statemap '.$fn.' for '.$uri.'.</font>');
         &unlink_tmpfiles($fn);          &unlink_tmpfiles($fn);
         if (open(LOCKFILE,">$fn.db.lock")) {          if (flock(LOCKFILE,LOCK_EX|LOCK_NB)) {
             my $lock=0;              $lock=1;
             if (flock(LOCKFILE,LOCK_EX|LOCK_NB)) {          }
                 $lock=1;          undef %randompick;
                 &unlink_tmpfiles($fn);          undef %hiddenurl;
             }          undef %encurl;
             undef %randompick;          $errtext='';
             undef %hiddenurl;          $retfrid='';
             undef %encurl;   #
             $retfrid='';   # Once more through the routine of tying and loading and so on.
             if ($lock) {   #
                 if (tie(%hash,'GDBM_File',"$fn.db",&GDBM_WRCREAT(),0640)) {          if ($lock) {
                     if (tie(%parmhash,'GDBM_File',$fn.'_parms.db',&GDBM_WRCREAT(),0640)) {              if (tie(%hash,'GDBM_File',"$fn.db",&GDBM_WRCREAT(),0640)) {
                         $gotstate = &build_tmp_hashes($uri,$fn,$short,\%cenv);                  if (tie(%parmhash,'GDBM_File',$fn.'_parms.db',&GDBM_WRCREAT(),0640)) {
                         unless ($gotstate) {                      $gotstate = &build_tmp_hashes($uri,$fn,$short,\%cenv); # TODO: User dependent?
                             &Apache::lonnet::logthis('<font color="blue">WARNING: '.                      unless ($gotstate) {
                                 'Failed to write statemap at second attempt '.$fn.' for '.$uri.'.</font>');  
                         }  
                         unless (untie(%parmhash)) {  
                             &Apache::lonnet::logthis('<font color="blue">WARNING: '.  
                                 'Could not untie coursemap parmhash '.$fn.'.db for '.$uri.'.</font>');  
                         }  
                     } else {  
                         &Apache::lonnet::logthis('<font color="blue">WARNING: '.                          &Apache::lonnet::logthis('<font color="blue">WARNING: '.
                             'Could not tie coursemap '.$fn.'__parms.db for '.$uri.'.</font>');                              'Failed to write statemap at second attempt '.$fn.' for '.$uri.'.</font>');
                     }                      }
                     unless (untie(%hash)) {                      unless (untie(%parmhash)) {
                         &Apache::lonnet::logthis('<font color="blue">WARNING: '.                          &Apache::lonnet::logthis('<font color="blue">WARNING: '.
                             'Could not untie coursemap hash '.$fn.'.db for '.$uri.'.</font>');                              'Could not untie coursemap parmhash '.$fn.'.db for '.$uri.'.</font>');
                     }                      }
                } else {                  } else {
                    &Apache::lonnet::logthis('<font color="blue">WARNING: '.                      &Apache::lonnet::logthis('<font color="blue">WARNING: '.
                        'Could not tie coursemap '.$fn.'.db for '.$uri.'.</font>');                          'Could not tie coursemap '.$fn.'__parms.db for '.$uri.'.</font>');
                }                  }
                flock(LOCKFILE,LOCK_UN);                  unless (untie(%hash)) {
                close(LOCKFILE);                      &Apache::lonnet::logthis('<font color="blue">WARNING: '.
                           'Could not untie coursemap hash '.$fn.'.db for '.$uri.'.</font>');
                   }
             } else {              } else {
                 &Apache::lonnet::logthis('<font color="blue">WARNING: '.                 &Apache::lonnet::logthis('<font color="blue">WARNING: '.
                 'Could not obtain lock to tie coursemap hash '.$fn.'.db for '.$uri.'.</font>');                     'Could not tie coursemap '.$fn.'.db for '.$uri.'.</font>');
             }              }
     close(LOCKFILE);              flock(LOCKFILE,LOCK_UN);
               $lock = 0;
           } else {
       # Failed to get the immediate lock.
   
               &Apache::lonnet::logthis('<font color="blue">WARNING: '.
               'Could not obtain lock to tie coursemap hash '.$fn.'.db for '.$uri.'.</font>');
         }          }
     }      }
       close(LOCKFILE);
     unless (($errtext eq '') || ($env{'request.course.uri'} =~ m{^/uploaded/})) {      unless (($errtext eq '') || ($env{'request.course.uri'} =~ m{^/uploaded/})) {
         &Apache::lonmsg::author_res_msg($env{'request.course.uri'},          &Apache::lonmsg::author_res_msg($env{'request.course.uri'},
                                         $errtext);                                          $errtext); # TODO: User dependent?
     }      }
 # ------------------------------------------------- Check for critical messages  # ------------------------------------------------- Check for critical messages
   
   #  Depends on user must parameterize this as well..or separate as this is:
   #  more part of determining what someone sees on entering a course?
   
     my @what=&Apache::lonnet::dump('critical',$env{'user.domain'},      my @what=&Apache::lonnet::dump('critical',$env{'user.domain'},
    $env{'user.name'});     $env{'user.name'});
     if ($what[0]) {      if ($what[0]) {
Line 817  sub readmap { Line 1430  sub readmap {
     return ($retfurl,$errtext);      return ($retfurl,$errtext);
 }  }
   
   #
   #  This sub is called when the course hash and the param hash have been tied and
   #  their lock file is held.
   #  Parameters:
   #     $uri      -  URI that identifies the course.
   #     $fn       -  The base path/filename of the files that make up the context
   #                  being built.
   #     $short    -  Short course name.
   #     $cenvref  -  Reference to the course environment hash returned by 
   #                  Apache::lonnet::coursedescription
   #
   #  Assumptions:
   #    The globals
   #    %hash, %paramhash are tied to their gdbm files and we hold the lock on them.
   #
 sub build_tmp_hashes {  sub build_tmp_hashes {
     my ($uri,$fn,$short,$cenvref) = @_;      my ($uri,$fn,$short,$cenvref) = @_;
       
     unless(ref($cenvref) eq 'HASH') {      unless(ref($cenvref) eq 'HASH') {
         return;          return;
     }      }
     my %cenv = %{$cenvref};      my %cenv = %{$cenvref};
     my $gotstate = 0;      my $gotstate = 0;
     %hash=();      %hash=(); # empty the global course and  parameter hashes.
     %parmhash=();      %parmhash=();
     $errtext='';      $errtext=''; # No error messages yet.
     $pc=0;      $pc=0;
     &clear_mapalias_count();      &clear_mapalias_count();
     &processversionfile(%cenv);      &processversionfile(%cenv);
   
       # URI Of the map file.
   
     my $furi=&Apache::lonnet::clutter($uri);      my $furi=&Apache::lonnet::clutter($uri);
       #
       #  the map staring points.
       #
     $hash{'src_0.0'}=&versiontrack($furi);      $hash{'src_0.0'}=&versiontrack($furi);
     $hash{'title_0.0'}=&Apache::lonnet::metadata($uri,'title');      $hash{'title_0.0'}=&Apache::lonnet::metadata($uri,'title');
     $hash{'ids_'.$furi}='0.0';      $hash{'ids_'.$furi}='0.0';
     $hash{'is_map_0.0'}=1;      $hash{'is_map_0.0'}=1;
     &loadmap($uri,'0.0');  
       # Load the map.. note that loadmap may implicitly recurse if the map contains 
       # sub-maps.
   
   
       &loadmap($uri,'0.0',$short);
   
       #  The code below only executes if there is a starting point for the map>
       #  Q/BUG??? If there is no start resource for the map should that be an error?
       #
   
     if (defined($hash{'map_start_'.$uri})) {      if (defined($hash{'map_start_'.$uri})) {
         &Apache::lonnet::appenv({"request.course.id"  => $short,          &Apache::lonnet::appenv({"request.course.id"  => $short,
                                  "request.course.fn"  => $fn,                                   "request.course.fn"  => $fn,
                                  "request.course.uri" => $uri});                                   "request.course.uri" => $uri,
                                    "request.course.tied" => time});
         $env{'request.course.id'}=$short;          $env{'request.course.id'}=$short;
         &traceroute('0',$hash{'map_start_'.$uri},'&');          &traceroute('0',$hash{'map_start_'.$uri},'&');
         &accinit($uri,$short,$fn);          &accinit($uri,$short,$fn);
         &hiddenurls();          &hiddenurls();
           &mapcrumbs();
     }      }
     $errtext .= &get_mapalias_errors();      $errtext .= &get_mapalias_errors();
 # ------------------------------------------------------- Put versions into src  # ------------------------------------------------------- Put versions into src
Line 888  sub build_tmp_hashes { Line 1535  sub build_tmp_hashes {
   
 sub unlink_tmpfiles {  sub unlink_tmpfiles {
     my ($fn) = @_;      my ($fn) = @_;
     if ($fn =~ m{^\Q$Apache::lonnet::perlvar{'lonUsersDir'}\E/tmp/}) {      my $file_dir = dirname($fn);
   
       if ("$file_dir/" eq LONCAPA::tempdir()) {
         my @files = qw (.db _symb.db .state _parms.db);          my @files = qw (.db _symb.db .state _parms.db);
         foreach my $file (@files) {          foreach my $file (@files) {
             if (-e $fn.$file) {              if (-e $fn.$file) {
Line 942  sub evalstate { Line 1591  sub evalstate {
     return $state;      return $state;
 }  }
   
   #  This block seems to have code to manage/detect doubly defined
   #  aliases in maps.
   
 {  {
     my %mapalias_cache;      my %mapalias_cache;
     sub count_mapalias {      sub count_mapalias {
Line 962  sub evalstate { Line 1614  sub evalstate {
      $count++;       $count++;
  }   }
  my ($mapid) = split(/\./,$id);   my ($mapid) = split(/\./,$id);
                          &mt('Resource "[_1]" <br /> in Map "[_2]"',                           &mt('Resource [_1][_2]in Map [_3]',
      $hash{'title_'.$id},       $hash{'title_'.$id},'<br />',
      $hash{'title_'.$hash{'ids_'.$hash{'map_id_'.$mapid}}});       $hash{'title_'.$hash{'ids_'.$hash{'map_id_'.$mapid}}});
      } (@{ $mapalias_cache{$mapalias} }));       } (@{ $mapalias_cache{$mapalias} }));
     next if ($count < 2);      next if ($count < 2);

Removed from v.1.132  
changed lines
  Added in v.1.153


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