IkiWiki/Plugin/aggregate.pm

   1 #!/usr/bin/perl
   2 # Feed aggregation plugin.
   3 package IkiWiki::Plugin::aggregate;
   4
   5 use warnings;
   6 use strict;
   7 use IkiWiki 2.00;
   8 use HTML::Parser;
   9 use HTML::Tagset;
  10 use HTML::Entities;
  11 use URI;
  12 use open qw{:utf8 :std};
  13
  14 my %feeds;
  15 my %guids;
  16
  17 sub import { #{{{
  18         hook(type => "getopt", id => "aggregate", call => \&getopt);
  19         hook(type => "checkconfig", id => "aggregate", call => \&checkconfig);
  20         hook(type => "needsbuild", id => "aggregate", call => \&needsbuild);
  21         hook(type => "preprocess", id => "aggregate", call => \&preprocess);
  22         hook(type => "delete", id => "aggregate", call => \&delete);
  23         hook(type => "savestate", id => "aggregate", call => \&savestate);
  24         hook(type => "htmlize", id => "_aggregated", call => \&htmlize);
  25         if (exists $config{aggregate_webtrigger} && $config{aggregate_webtrigger}) {
  26                 hook(type => "cgi", id => "aggregate", call => \&cgi);
  27         }
  28 } # }}}
  29
  30 sub getopt () { #{{{
  31         eval q{use Getopt::Long};
  32         error($@) if $@;
  33         Getopt::Long::Configure('pass_through');
  34         GetOptions(
  35                 "aggregate" => \$config{aggregate},
  36                 "aggregateinternal!" => \$config{aggregateinternal},
  37         );
  38 } #}}}
  39
  40 sub checkconfig () { #{{{
  41         if ($config{aggregate} && ! ($config{post_commit} &&
  42                                      IkiWiki::commit_hook_enabled())) {
  43                 launchaggregation();
  44         }
  45 } #}}}
  46
  47 sub cgi ($) { #{{{
  48         my $cgi=shift;
  49
  50         if (defined $cgi->param('do') &&
  51             $cgi->param("do") eq "aggregate_webtrigger") {
  52                 $|=1;
  53                 print "Content-Type: text/plain\n\n";
  54                 $config{cgi}=0;
  55                 $config{verbose}=1;
  56                 $config{syslog}=0;
  57                 print gettext("Aggregation triggered via web.")."\n\n";
  58                 if (launchaggregation()) {
  59                         IkiWiki::lockwiki();
  60                         IkiWiki::loadindex();
  61                         require IkiWiki::Render;
  62                         IkiWiki::refresh();
  63                         IkiWiki::saveindex();
  64                 }
  65                 else {
  66                         print gettext("Nothing to do right now, all feeds are up-to-date!")."\n";
  67                 }
  68                 exit 0;
  69         }
  70 } #}}}
  71
  72 sub launchaggregation () { #{{{
  73         # See if any feeds need aggregation.
  74         loadstate();
  75         my @feeds=needsaggregate();
  76         return unless @feeds;
  77         if (! lockaggregate()) {
  78                 debug("an aggregation process is already running");
  79                 return;
  80         }
  81         # force a later rebuild of source pages
  82         $IkiWiki::forcerebuild{$_->{sourcepage}}=1
  83                 foreach @feeds;
  84
  85         # Fork a child process to handle the aggregation.
  86         # The parent process will then handle building the
  87         # result. This avoids messy code to clear state
  88         # accumulated while aggregating.
  89         defined(my $pid = fork) or error("Can't fork: $!");
  90         if (! $pid) {
  91                 IkiWiki::loadindex();
  92                 # Aggregation happens without the main wiki lock
  93                 # being held. This allows editing pages etc while
  94                 # aggregation is running.
  95                 aggregate(@feeds);
  96
  97                 IkiWiki::lockwiki;
  98                 # Merge changes, since aggregation state may have
  99                 # changed on disk while the aggregation was happening.
 100                 mergestate();
 101                 expire();
 102                 savestate();
 103                 IkiWiki::unlockwiki;
 104                 exit 0;
 105         }
 106         waitpid($pid,0);
 107         if ($?) {
 108                 error "aggregation failed with code $?";
 109         }
 110
 111         clearstate();
 112         unlockaggregate();
 113
 114         return 1;
 115 } #}}}
 116
 117 #  Pages with extension _aggregated have plain html markup, pass through.
 118 sub htmlize (@) { #{{{
 119         my %params=@_;
 120         return $params{content};
 121 } #}}}
 122
 123 sub migrate_to_internal { #{{{
 124
 125         if (! lockaggregate()) {
 126                 error("an aggregation process is already running");
 127                 return;
 128         }
 129
 130         IkiWiki::lockwiki();
 131         loadstate();
 132
 133         foreach my $data (values %guids) {
 134                 next unless $data->{page};
 135
 136                 $config{aggregateinternal} = 0;
 137                 my $oldname = pagefile($data->{page});
 138
 139                 $config{aggregateinternal} = 1;
 140                 my $newname = pagefile($data->{page});
 141
 142                 print "I: $oldname -> $newname\n";
 143                 if (-e $newname) {
 144                         if (-e $oldname) {
 145                                 error("$newname already exists");
 146                         }
 147                         else {
 148                                 print STDERR
 149                                         "W: already renamed to $newname?\n";
 150                         }
 151                 }
 152                 elsif (-e $oldname) {
 153                         rename($oldname, $newname) || error("$!");
 154                 }
 155                 else {
 156                         print "W: $oldname not found\n";
 157                 }
 158         }
 159
 160         savestate();
 161         IkiWiki::unlockwiki;
 162
 163         unlockaggregate();
 164 } #}}}
 165
 166 sub needsbuild (@) { #{{{
 167         my $needsbuild=shift;
 168
 169         loadstate();
 170
 171         foreach my $feed (values %feeds) {
 172                 if (exists $pagesources{$feed->{sourcepage}} &&
 173                     grep { $_ eq $pagesources{$feed->{sourcepage}} } @$needsbuild) {
 174                         # Mark all feeds originating on this page as
 175                         # not yet seen; preprocess will unmark those that
 176                         # still exist.
 177                         markunseen($feed->{sourcepage});
 178                 }
 179         }
 180 } # }}}
 181
 182 sub preprocess (@) { #{{{
 183         my %params=@_;
 184
 185         foreach my $required (qw{name url}) {
 186                 if (! exists $params{$required}) {
 187                         error sprintf(gettext("missing %s parameter"), $required)
 188                 }
 189         }
 190
 191         my $feed={};
 192         my $name=$params{name};
 193         if (exists $feeds{$name}) {
 194                 $feed=$feeds{$name};
 195         }
 196         else {
 197                 $feeds{$name}=$feed;
 198         }
 199         $feed->{name}=$name;
 200         $feed->{sourcepage}=$params{page};
 201         $feed->{url}=$params{url};
 202         my $dir=exists $params{dir} ? $params{dir} : $params{page}."/".IkiWiki::titlepage($params{name});
 203         $dir=~s/^\/+//;
 204         ($dir)=$dir=~/$config{wiki_file_regexp}/;
 205         $feed->{dir}=$dir;
 206         $feed->{feedurl}=defined $params{feedurl} ? $params{feedurl} : "";
 207         $feed->{updateinterval}=defined $params{updateinterval} ? $params{updateinterval} * 60 : 15 * 60;
 208         $feed->{expireage}=defined $params{expireage} ? $params{expireage} : 0;
 209         $feed->{expirecount}=defined $params{expirecount} ? $params{expirecount} : 0;
 210         if (exists $params{template}) {
 211                 $params{template}=~s/[^-_a-zA-Z0-9]+//g;
 212         }
 213         else {
 214                 $params{template} = "aggregatepost"
 215         }
 216         $feed->{template}=$params{template} . ".tmpl";
 217         delete $feed->{unseen};
 218         $feed->{lastupdate}=0 unless defined $feed->{lastupdate};
 219         $feed->{numposts}=0 unless defined $feed->{numposts};
 220         $feed->{newposts}=0 unless defined $feed->{newposts};
 221         $feed->{message}=gettext("new feed") unless defined $feed->{message};
 222         $feed->{error}=0 unless defined $feed->{error};
 223         $feed->{tags}=[];
 224         while (@_) {
 225                 my $key=shift;
 226                 my $value=shift;
 227                 if ($key eq 'tag') {
 228                         push @{$feed->{tags}}, $value;
 229                 }
 230         }
 231
 232         return "<a href=\"".$feed->{url}."\">".$feed->{name}."</a>: ".
 233                ($feed->{error} ? "<em>" : "").$feed->{message}.
 234                ($feed->{error} ? "</em>" : "").
 235                " (".$feed->{numposts}." ".gettext("posts").
 236                ($feed->{newposts} ? "; ".$feed->{newposts}.
 237                                     " ".gettext("new") : "").
 238                ")";
 239 } # }}}
 240
 241 sub delete (@) { #{{{
 242         my @files=@_;
 243
 244         # Remove feed data for removed pages.
 245         foreach my $file (@files) {
 246                 my $page=pagename($file);
 247                 markunseen($page);
 248         }
 249 } #}}}
 250
 251 sub markunseen ($) { #{{{
 252         my $page=shift;
 253
 254         foreach my $id (keys %feeds) {
 255                 if ($feeds{$id}->{sourcepage} eq $page) {
 256                         $feeds{$id}->{unseen}=1;
 257                 }
 258         }
 259 } #}}}
 260
 261 my $state_loaded=0;
 262
 263 sub loadstate () { #{{{
 264         return if $state_loaded;
 265         $state_loaded=1;
 266         if (-e "$config{wikistatedir}/aggregate") {
 267                 open(IN, "$config{wikistatedir}/aggregate") ||
 268                         die "$config{wikistatedir}/aggregate: $!";
 269                 while (<IN>) {
 270                         $_=IkiWiki::possibly_foolish_untaint($_);
 271                         chomp;
 272                         my $data={};
 273                         foreach my $i (split(/ /, $_)) {
 274                                 my ($field, $val)=split(/=/, $i, 2);
 275                                 if ($field eq "name" || $field eq "feed" ||
 276                                     $field eq "guid" || $field eq "message") {
 277                                         $data->{$field}=decode_entities($val, " \t\n");
 278                                 }
 279                                 elsif ($field eq "tag") {
 280                                         push @{$data->{tags}}, $val;
 281                                 }
 282                                 else {
 283                                         $data->{$field}=$val;
 284                                 }
 285                         }
 286
 287                         if (exists $data->{name}) {
 288                                 $feeds{$data->{name}}=$data;
 289                         }
 290                         elsif (exists $data->{guid}) {
 291                                 $guids{$data->{guid}}=$data;
 292                         }
 293                 }
 294
 295                 close IN;
 296         }
 297 } #}}}
 298
 299 sub savestate () { #{{{
 300         return unless $state_loaded;
 301         garbage_collect();
 302         my $newfile="$config{wikistatedir}/aggregate.new";
 303         my $cleanup = sub { unlink($newfile) };
 304         open (OUT, ">$newfile") || error("open $newfile: $!", $cleanup);
 305         foreach my $data (values %feeds, values %guids) {
 306                 my @line;
 307                 foreach my $field (keys %$data) {
 308                         if ($field eq "name" || $field eq "feed" ||
 309                             $field eq "guid" || $field eq "message") {
 310                                 push @line, "$field=".encode_entities($data->{$field}, " \t\n");
 311                         }
 312                         elsif ($field eq "tags") {
 313                                 push @line, "tag=$_" foreach @{$data->{tags}};
 314                         }
 315                         else {
 316                                 push @line, "$field=".$data->{$field};
 317                         }
 318                 }
 319                 print OUT join(" ", @line)."\n" || error("write $newfile: $!", $cleanup);
 320         }
 321         close OUT || error("save $newfile: $!", $cleanup);
 322         rename($newfile, "$config{wikistatedir}/aggregate") ||
 323                 error("rename $newfile: $!", $cleanup);
 324 } #}}}
 325
 326 sub garbage_collect () { #{{{
 327         foreach my $name (keys %feeds) {
 328                 # remove any feeds that were not seen while building the pages
 329                 # that used to contain them
 330                 if ($feeds{$name}->{unseen}) {
 331                         delete $feeds{$name};
 332                 }
 333         }
 334
 335         foreach my $guid (values %guids) {
 336                 # any guid whose feed is gone should be removed
 337                 if (! exists $feeds{$guid->{feed}}) {
 338                         unlink pagefile($guid->{page})
 339                                 if exists $guid->{page};
 340                         delete $guids{$guid->{guid}};
 341                 }
 342                 # handle expired guids
 343                 elsif ($guid->{expired} && exists $guid->{page}) {
 344                         unlink pagefile($guid->{page});
 345                         delete $guid->{page};
 346                         delete $guid->{md5};
 347                 }
 348         }
 349 } #}}}
 350
 351 sub mergestate () { #{{{
 352         # Load the current state in from disk, and merge into it
 353         # values from the state in memory that might have changed
 354         # during aggregation.
 355         my %myfeeds=%feeds;
 356         my %myguids=%guids;
 357         clearstate();
 358         loadstate();
 359
 360         # All that can change in feed state during aggregation is a few
 361         # fields.
 362         foreach my $name (keys %myfeeds) {
 363                 if (exists $feeds{$name}) {
 364                         foreach my $field (qw{message lastupdate numposts
 365                                               newposts error}) {
 366                                 $feeds{$name}->{$field}=$myfeeds{$name}->{$field};
 367                         }
 368                 }
 369         }
 370
 371         # New guids can be created during aggregation.
 372         # It's also possible that guids were removed from the on-disk state
 373         # while the aggregation was in process. That would only happen if
 374         # their feed was also removed, so any removed guids added back here
 375         # will be garbage collected later.
 376         foreach my $guid (keys %myguids) {
 377                 if (! exists $guids{$guid}) {
 378                         $guids{$guid}=$myguids{$guid};
 379                 }
 380         }
 381 } #}}}
 382
 383 sub clearstate () { #{{{
 384         %feeds=();
 385         %guids=();
 386         $state_loaded=0;
 387 } #}}}
 388
 389 sub expire () { #{{{
 390         foreach my $feed (values %feeds) {
 391                 next unless $feed->{expireage} || $feed->{expirecount};
 392                 my $count=0;
 393                 my %seen;
 394                 foreach my $item (sort { $IkiWiki::pagectime{$b->{page}} <=> $IkiWiki::pagectime{$a->{page}} }
 395                                   grep { exists $_->{page} && $_->{feed} eq $feed->{name} && $IkiWiki::pagectime{$_->{page}} }
 396                                   values %guids) {
 397                         if ($feed->{expireage}) {
 398                                 my $days_old = (time - $IkiWiki::pagectime{$item->{page}}) / 60 / 60 / 24;
 399                                 if ($days_old > $feed->{expireage}) {
 400                                         debug(sprintf(gettext("expiring %s (%s days old)"),
 401                                                 $item->{page}, int($days_old)));
 402                                         $item->{expired}=1;
 403                                 }
 404                         }
 405                         elsif ($feed->{expirecount} &&
 406                                $count >= $feed->{expirecount}) {
 407                                 debug(sprintf(gettext("expiring %s"), $item->{page}));
 408                                 $item->{expired}=1;
 409                         }
 410                         else {
 411                                 if (! $seen{$item->{page}}) {
 412                                         $seen{$item->{page}}=1;
 413                                         $count++;
 414                                 }
 415                         }
 416                 }
 417         }
 418 } #}}}
 419
 420 sub needsaggregate () { #{{{
 421         return values %feeds if $config{rebuild};
 422         return grep { time - $_->{lastupdate} >= $_->{updateinterval} } values %feeds;
 423 } #}}}
 424
 425 sub aggregate (@) { #{{{
 426         eval q{use XML::Feed};
 427         error($@) if $@;
 428         eval q{use URI::Fetch};
 429         error($@) if $@;
 430
 431         foreach my $feed (@_) {
 432                 $feed->{lastupdate}=time;
 433                 $feed->{newposts}=0;
 434                 $feed->{message}=sprintf(gettext("processed ok at %s"),
 435                         displaytime($feed->{lastupdate}));
 436                 $feed->{error}=0;
 437
 438                 debug(sprintf(gettext("checking feed %s ..."), $feed->{name}));
 439
 440                 if (! length $feed->{feedurl}) {
 441                         my @urls=XML::Feed->find_feeds($feed->{url});
 442                         if (! @urls) {
 443                                 $feed->{message}=sprintf(gettext("could not find feed at %s"), $feed->{url});
 444                                 $feed->{error}=1;
 445                                 debug($feed->{message});
 446                                 next;
 447                         }
 448                         $feed->{feedurl}=pop @urls;
 449                 }
 450                 my $res=URI::Fetch->fetch($feed->{feedurl});
 451                 if (! $res) {
 452                         $feed->{message}=URI::Fetch->errstr;
 453                         $feed->{error}=1;
 454                         debug($feed->{message});
 455                         next;
 456                 }
 457                 if ($res->status == URI::Fetch::URI_GONE()) {
 458                         $feed->{message}=gettext("feed not found");
 459                         $feed->{error}=1;
 460                         debug($feed->{message});
 461                         next;
 462                 }
 463                 my $content=$res->content;
 464                 my $f=eval{XML::Feed->parse(\$content)};
 465                 if ($@) {
 466                         # One common cause of XML::Feed crashing is a feed
 467                         # that contains invalid UTF-8 sequences. Convert
 468                         # feed to ascii to try to work around.
 469                         $feed->{message}.=" ".sprintf(gettext("(invalid UTF-8 stripped from feed)"));
 470                         $content=Encode::decode_utf8($content, 0);
 471                         $f=eval{XML::Feed->parse(\$content)};
 472                 }
 473                 if ($@) {
 474                         # Another possibility is badly escaped entities.
 475                         $feed->{message}.=" ".sprintf(gettext("(feed entities escaped)"));
 476                         $content=~s/\&(?!amp)(\w+);/&amp;$1;/g;
 477                         $content=Encode::decode_utf8($content, 0);
 478                         $f=eval{XML::Feed->parse(\$content)};
 479                 }
 480                 if ($@) {
 481                         $feed->{message}=gettext("feed crashed XML::Feed!")." ($@)";
 482                         $feed->{error}=1;
 483                         debug($feed->{message});
 484                         next;
 485                 }
 486                 if (! $f) {
 487                         $feed->{message}=XML::Feed->errstr;
 488                         $feed->{error}=1;
 489                         debug($feed->{message});
 490                         next;
 491                 }
 492
 493                 foreach my $entry ($f->entries) {
 494                         add_page(
 495                                 feed => $feed,
 496                                 copyright => $f->copyright,
 497                                 title => defined $entry->title ? decode_entities($entry->title) : "untitled",
 498                                 link => $entry->link,
 499                                 content => defined $entry->content->body ? $entry->content->body : "",
 500                                 guid => defined $entry->id ? $entry->id : time."_".$feed->{name},
 501                                 ctime => $entry->issued ? ($entry->issued->epoch || time) : time,
 502                         );
 503                 }
 504         }
 505 } #}}}
 506
 507 sub add_page (@) { #{{{
 508         my %params=@_;
 509
 510         my $feed=$params{feed};
 511         my $guid={};
 512         my $mtime;
 513         if (exists $guids{$params{guid}}) {
 514                 # updating an existing post
 515                 $guid=$guids{$params{guid}};
 516                 return if $guid->{expired};
 517         }
 518         else {
 519                 # new post
 520                 $guid->{guid}=$params{guid};
 521                 $guids{$params{guid}}=$guid;
 522                 $mtime=$params{ctime};
 523                 $feed->{numposts}++;
 524                 $feed->{newposts}++;
 525
 526                 # assign it an unused page
 527                 my $page=IkiWiki::titlepage($params{title});
 528                 # escape slashes and periods in title so it doesn't specify
 529                 # directory name or trigger ".." disallowing code.
 530                 $page=~s!([/.])!"__".ord($1)."__"!eg;
 531                 $page=$feed->{dir}."/".$page;
 532                 ($page)=$page=~/$config{wiki_file_regexp}/;
 533                 if (! defined $page || ! length $page) {
 534                         $page=$feed->{dir}."/item";
 535                 }
 536                 my $c="";
 537                 while (exists $IkiWiki::pagecase{lc $page.$c} ||
 538                        -e pagefile($page.$c)) {
 539                         $c++
 540                 }
 541
 542                 # Make sure that the file name isn't too long.
 543                 # NB: This doesn't check for path length limits.
 544                 my $max=POSIX::pathconf($config{srcdir}, &POSIX::_PC_NAME_MAX);
 545                 if (defined $max && length(htmlfn($page)) >= $max) {
 546                         $c="";
 547                         $page=$feed->{dir}."/item";
 548                         while (exists $IkiWiki::pagecase{lc $page.$c} ||
 549                                -e pagefile($page.$c)) {
 550                                 $c++
 551                         }
 552                 }
 553
 554                 $guid->{page}=$page;
 555                 debug(sprintf(gettext("creating new page %s"), $page));
 556         }
 557         $guid->{feed}=$feed->{name};
 558
 559         # To write or not to write? Need to avoid writing unchanged pages
 560         # to avoid unneccessary rebuilding. The mtime from rss cannot be
 561         # trusted; let's use a digest.
 562         eval q{use Digest::MD5 'md5_hex'};
 563         error($@) if $@;
 564         require Encode;
 565         my $digest=md5_hex(Encode::encode_utf8($params{content}));
 566         return unless ! exists $guid->{md5} || $guid->{md5} ne $digest || $config{rebuild};
 567         $guid->{md5}=$digest;
 568
 569         # Create the page.
 570         my $template=template($feed->{template}, blind_cache => 1);
 571         $template->param(title => $params{title})
 572                 if defined $params{title} && length($params{title});
 573         $template->param(content => htmlescape(htmlabs($params{content}, $feed->{feedurl})));
 574         $template->param(name => $feed->{name});
 575         $template->param(url => $feed->{url});
 576         $template->param(copyright => $params{copyright})
 577                 if defined $params{copyright} && length $params{copyright};
 578         $template->param(permalink => urlabs($params{link}, $feed->{feedurl}))
 579                 if defined $params{link};
 580         if (ref $feed->{tags}) {
 581                 $template->param(tags => [map { tag => $_ }, @{$feed->{tags}}]);
 582         }
 583         writefile(htmlfn($guid->{page}), $config{srcdir},
 584                 $template->output);
 585
 586         # Set the mtime, this lets the build process get the right creation
 587         # time on record for the new page.
 588         utime $mtime, $mtime, pagefile($guid->{page})
 589                 if defined $mtime && $mtime <= time;
 590 } #}}}
 591
 592 sub htmlescape ($) { #{{{
 593         # escape accidental wikilinks and preprocessor stuff
 594         my $html=shift;
 595         $html=~s/(?<!\\)\[\[/\\\[\[/g;
 596         return $html;
 597 } #}}}
 598
 599 sub urlabs ($$) { #{{{
 600         my $url=shift;
 601         my $urlbase=shift;
 602
 603         URI->new_abs($url, $urlbase)->as_string;
 604 } #}}}
 605
 606 sub htmlabs ($$) { #{{{
 607         # Convert links in html from relative to absolute.
 608         # Note that this is a heuristic, which is not specified by the rss
 609         # spec and may not be right for all feeds. Also, see Debian
 610         # bug #381359.
 611         my $html=shift;
 612         my $urlbase=shift;
 613
 614         my $ret="";
 615         my $p = HTML::Parser->new(api_version => 3);
 616         $p->handler(default => sub { $ret.=join("", @_) }, "text");
 617         $p->handler(start => sub {
 618                 my ($tagname, $pos, $text) = @_;
 619                 if (ref $HTML::Tagset::linkElements{$tagname}) {
 620                         while (4 <= @$pos) {
 621                                 # use attribute sets from right to left
 622                                 # to avoid invalidating the offsets
 623                                 # when replacing the values
 624                                 my($k_offset, $k_len, $v_offset, $v_len) =
 625                                         splice(@$pos, -4);
 626                                 my $attrname = lc(substr($text, $k_offset, $k_len));
 627                                 next unless grep { $_ eq $attrname } @{$HTML::Tagset::linkElements{$tagname}};
 628                                 next unless $v_offset; # 0 v_offset means no value
 629                                 my $v = substr($text, $v_offset, $v_len);
 630                                 $v =~ s/^([\'\"])(.*)\1$/$2/;
 631                                 my $new_v=urlabs($v, $urlbase);
 632                                 $new_v =~ s/\"/&quot;/g; # since we quote with ""
 633                                 substr($text, $v_offset, $v_len) = qq("$new_v");
 634                         }
 635                 }
 636                 $ret.=$text;
 637         }, "tagname, tokenpos, text");
 638         $p->parse($html);
 639         $p->eof;
 640
 641         return $ret;
 642 } #}}}
 643
 644 sub pagefile ($) { #{{{
 645         my $page=shift;
 646
 647         return "$config{srcdir}/".htmlfn($page);
 648 } #}}}
 649
 650 sub htmlfn ($) { #{{{
 651         return shift().".".($config{aggregateinternal} ? "_aggregated" : $config{htmlext});
 652 } #}}}
 653
 654 my $aggregatelock;
 655
 656 sub lockaggregate () { #{{{
 657         # Take an exclusive lock to prevent multiple concurrent aggregators.
 658         # Returns true if the lock was aquired.
 659         if (! -d $config{wikistatedir}) {
 660                 mkdir($config{wikistatedir});
 661         }
 662         open($aggregatelock, '>', "$config{wikistatedir}/aggregatelock") ||
 663                 error ("cannot open to $config{wikistatedir}/aggregatelock: $!");
 664         if (! flock($aggregatelock, 2 | 4)) { # LOCK_EX | LOCK_NB
 665                 close($aggregatelock) || error("failed closing aggregatelock: $!");
 666                 return 0;
 667         }
 668         return 1;
 669 } #}}}
 670
 671 sub unlockaggregate () { #{{{
 672         return close($aggregatelock) if $aggregatelock;
 673         return;
 674 } #}}}
 675
 676 1