IkiWiki/Render.pm



#!/usr/bin/perl

package IkiWiki;

use warnings;
use strict;
use IkiWiki;
use Encode;

my %backlinks;
my $backlinks_calculated=0;

sub calculate_backlinks () {
    return if $backlinks_calculated;
    %backlinks=();
    foreach my $page (keys %links) {
        foreach my $link (@{$links{$page}}) {
            my $bestlink=bestlink($page, $link);
            if (length $bestlink && $bestlink ne $page) {
                $backlinks{$bestlink}{$page}=1;
            }
        }
    }
    $backlinks_calculated=1;
}

sub backlinks ($) {
    my $page=shift;

    calculate_backlinks();

    my @links;
    foreach my $p (keys %{$backlinks{$page}}) {
        my $href=urlto($p, $page);
                
        # Trim common dir prefixes from both pages.
        my $p_trimmed=$p;
        my $page_trimmed=$page;
        my $dir;
        1 while (($dir)=$page_trimmed=~m!^([^/]+/)!) &&
                defined $dir &&
                $p_trimmed=~s/^\Q$dir\E// &&
                $page_trimmed=~s/^\Q$dir\E//;
                   
        push @links, { url => $href, page => pagetitle($p_trimmed) };
    }
    return @links;
}

sub genpage ($$) {
    my $page=shift;
    my $content=shift;

    my $templatefile;
    run_hooks(templatefile => sub {
        return if defined $templatefile;
        my $file=shift->(page => $page);
        if (defined $file && defined template_file($file)) {
            $templatefile=$file;
        }
    });
    my $template=template(defined $templatefile ? $templatefile : 'page.tmpl', blind_cache => 1);
    my $actions=0;

    if (length $config{cgiurl}) {
        $template->param(editurl => cgiurl(do => "edit", page => $page))
            if IkiWiki->can("cgi_editpage");
        $template->param(prefsurl => cgiurl(do => "prefs"));
        $actions++;
    }
        
    if (defined $config{historyurl} && length $config{historyurl}) {
        my $u=$config{historyurl};
        $u=~s/\[\[file\]\]/$pagesources{$page}/g;
        $template->param(historyurl => $u);
        $actions++;
    }
    if ($config{discussion}) {
        my $discussionlink=lc(gettext("Discussion"));
        if ($page !~ /.*\/\Q$discussionlink\E$/ &&
           (length $config{cgiurl} ||
            exists $links{$page."/".$discussionlink})) {
            $template->param(discussionlink => htmllink($page, $page, gettext("Discussion"), noimageinline => 1, forcesubpage => 1));
            $actions++;
        }
    }

    if ($actions) {
        $template->param(have_actions => 1);
    }

    my @backlinks=sort { $a->{page} cmp $b->{page} } backlinks($page);
    my ($backlinks, $more_backlinks);
    if (@backlinks <= $config{numbacklinks} || ! $config{numbacklinks}) {
        $backlinks=\@backlinks;
        $more_backlinks=[];
    }
    else {
        $backlinks=[@backlinks[0..$config{numbacklinks}-1]];
        $more_backlinks=[@backlinks[$config{numbacklinks}..$#backlinks]];
    }

    $template->param(
        title => $page eq 'index' 
            ? $config{wikiname} 
            : pagetitle(basename($page)),
        wikiname => $config{wikiname},
        content => $content,
        backlinks => $backlinks,
        more_backlinks => $more_backlinks,
        mtime => displaytime($pagemtime{$page}),
        ctime => displaytime($pagectime{$page}),
        baseurl => baseurl($page),
    );

    run_hooks(pagetemplate => sub {
        shift->(page => $page, destpage => $page, template => $template);
    });
    
    $content=$template->output;
    
    run_hooks(postscan => sub {
        shift->(page => $page, content => $content);
    });

    run_hooks(format => sub {
        $content=shift->(
            page => $page,
            content => $content,
        );
    });

    return $content;
}

sub scan ($) {
    my $file=shift;

    my $type=pagetype($file);
    if (defined $type) {
        my $srcfile=srcfile($file);
        my $content=readfile($srcfile);
        my $page=pagename($file);
        will_render($page, htmlpage($page), 1);

        if ($config{discussion}) {
            # Discussion links are a special case since they're
            # not in the text of the page, but on its template.
            $links{$page}=[ $page."/".lc(gettext("Discussion")) ];
        }
        else {
            $links{$page}=[];
        }

        run_hooks(scan => sub {
            shift->(
                page => $page,
                content => $content,
            );
        });

        # Preprocess in scan-only mode.
        preprocess($page, $page, $content, 1);
    }
    else {
        will_render($file, $file, 1);
    }
}

sub fast_file_copy (@) {
    my $srcfile=shift;
    my $destfile=shift;
    my $srcfd=shift;
    my $destfd=shift;
    my $cleanup=shift;

    my $blksize = 16384;
    my ($len, $buf, $written);
    while ($len = sysread $srcfd, $buf, $blksize) {
        if (! defined $len) {
            next if $! =~ /^Interrupted/;
            error("failed to read $srcfile: $!", $cleanup);
        }
        my $offset = 0;
        while ($len) {
            defined($written = syswrite $destfd, $buf, $len, $offset)
                or error("failed to write $destfile: $!", $cleanup);
            $len -= $written;
            $offset += $written;
        }
    }
}

sub render ($) {
    my $file=shift;
    
    my $type=pagetype($file);
    my $srcfile=srcfile($file);
    if (defined $type) {
        my $page=pagename($file);
        delete $depends{$page};
        will_render($page, htmlpage($page), 1);
        return if $type=~/^_/;
        
        my $content=htmlize($page, $page, $type,
            linkify($page, $page,
            preprocess($page, $page,
            filter($page, $page,
            readfile($srcfile)))));
        
        my $output=htmlpage($page);
        writefile($output, $config{destdir}, genpage($page, $content));
    }
    else {
        delete $depends{$file};
        will_render($file, $file, 1);
        
        if ($config{hardlink}) {
            # only hardlink if owned by same user
            my @stat=stat($srcfile);
            if ($stat[4] == $>) {
                prep_writefile($file, $config{destdir});
                unlink($config{destdir}."/".$file);
                if (link($srcfile, $config{destdir}."/".$file)) {
                    return;
                }
            }
            # if hardlink fails, fall back to copying
        }
        
        my $srcfd=readfile($srcfile, 1, 1);
        writefile($file, $config{destdir}, undef, 1, sub {
            fast_file_copy($srcfile, $file, $srcfd, @_);
        });
    }
}

sub prune ($) {
    my $file=shift;

    unlink($file);
    my $dir=dirname($file);
    while (rmdir($dir)) {
        $dir=dirname($dir);
    }
}

sub refresh () {
    # security check, avoid following symlinks in the srcdir path by default
    my $test=$config{srcdir};
    while (length $test) {
        if (-l $test && ! $config{allow_symlinks_before_srcdir}) {
            error(sprintf(gettext("symlink found in srcdir path (%s) -- set allow_symlinks_before_srcdir to allow this"), $test));
        }
        unless ($test=~s/\/+$//) {
            $test=dirname($test);
        }
    }
    
    run_hooks(refresh => sub { shift->() });

    # find existing pages
    my %exists;
    my @files;
    eval q{use File::Find};
    error($@) if $@;
    find({
        no_chdir => 1,
        wanted => sub {
            $_=decode_utf8($_);
            if (file_pruned($_, $config{srcdir})) {
                $File::Find::prune=1;
            }
            elsif (! -l $_ && ! -d _) {
                my ($f)=/$config{wiki_file_regexp}/; # untaint
                if (! defined $f) {
                    warn(sprintf(gettext("skipping bad filename %s"), $_)."\n");
                }
                else {
                    $f=~s/^\Q$config{srcdir}\E\/?//;
                    push @files, $f;
                    my $pagename = pagename($f);
                    if ($exists{$pagename}) {
                        debug(sprintf(gettext("%s has multiple possible source pages"), $pagename));
                    }
                    $exists{$pagename}=1;
                }
            }
        },
    }, $config{srcdir});
    foreach my $dir (@{$config{underlaydirs}}, $config{underlaydir}) {
        find({
            no_chdir => 1,
            wanted => sub {
                $_=decode_utf8($_);
                if (file_pruned($_, $dir)) {
                    $File::Find::prune=1;
                }
                elsif (! -l $_ && ! -d _) {
                    my ($f)=/$config{wiki_file_regexp}/; # untaint
                    if (! defined $f) {
                        warn(sprintf(gettext("skipping bad filename %s"), $_)."\n");
                    }
                    else {
                        $f=~s/^\Q$dir\E\/?//;
                        # avoid underlaydir
                        # override attacks; see
                        # security.mdwn
                        if (! -l "$config{srcdir}/$f" && 
                            ! -e _) {
                                my $page=pagename($f);
                            if (! $exists{$page}) {
                                push @files, $f;
                                $exists{$page}=1;
                            }
                        }
                    }
                }
            },
        }, $dir);
    };

    my (%rendered, @add, @del, @internal);
    # check for added or removed pages
    foreach my $file (@files) {
        my $page=pagename($file);
        if (exists $pagesources{$page} && $pagesources{$page} ne $file) {
            # the page has changed its type
            $forcerebuild{$page}=1;
        }
        $pagesources{$page}=$file;
        if (! $pagemtime{$page}) {
            if (isinternal($page)) {
                push @internal, $file;
            }
            else {
                push @add, $file;
                if ($config{getctime} && -e "$config{srcdir}/$file") {
                    eval {
                        my $time=rcs_getctime("$config{srcdir}/$file");
                        $pagectime{$page}=$time;
                    };
                    if ($@) {
                        print STDERR $@;
                    }
                }
            }
            $pagecase{lc $page}=$page;
            if (! exists $pagectime{$page}) {
                $pagectime{$page}=(srcfile_stat($file))[10];
            }
        }
    }
    foreach my $page (keys %pagemtime) {
        if (! $exists{$page}) {
            if (isinternal($page)) {
                push @internal, $pagesources{$page};
            }
            else {
                debug(sprintf(gettext("removing old page %s"), $page));
                push @del, $pagesources{$page};
            }
            $links{$page}=[];
            $renderedfiles{$page}=[];
            $pagemtime{$page}=0;
            prune($config{destdir}."/".$_)
                foreach @{$oldrenderedfiles{$page}};
            delete $pagesources{$page};
            foreach (keys %destsources) {
                if ($destsources{$_} eq $page) {
                    delete $destsources{$_};
                }
            }
        }
    }

    # find changed and new files
    my @needsbuild;
    foreach my $file (@files) {
        my $page=pagename($file);
        my ($srcfile, @stat)=srcfile_stat($file);
        if (! exists $pagemtime{$page} ||
            $stat[9] > $pagemtime{$page} ||
                $forcerebuild{$page}) {
            $pagemtime{$page}=$stat[9];
            if (isinternal($page)) {
                push @internal, $file;
                # Preprocess internal page in scan-only mode.
                preprocess($page, $page, readfile($srcfile), 1);
            }
            else {
                push @needsbuild, $file;
            }
        }
    }
    run_hooks(needsbuild => sub { shift->(\@needsbuild) });

    # scan and render files
    foreach my $file (@needsbuild) {
        debug(sprintf(gettext("scanning %s"), $file));
        scan($file);
    }
    calculate_backlinks();
    foreach my $file (@needsbuild) {
        debug(sprintf(gettext("rendering %s"), $file));
        render($file);
        $rendered{$file}=1;
    }
    foreach my $file (@internal) {
        # internal pages are not rendered
        my $page=pagename($file);
        delete $depends{$page};
        foreach my $old (@{$renderedfiles{$page}}) {
            delete $destsources{$old};
        }
        $renderedfiles{$page}=[];
    }
    
    # rebuild pages that link to added or removed pages
    if (@add || @del) {
        foreach my $f (@add, @del) {
            my $p=pagename($f);
            foreach my $page (keys %{$backlinks{$p}}) {
                my $file=$pagesources{$page};
                next if $rendered{$file};
                debug(sprintf(gettext("rendering %s, which links to %s"), $file, $p));
                render($file);
                $rendered{$file}=1;
            }
        }
    }

    if (%rendered || @del || @internal) {
        my @changed=(keys %rendered, @del);

        # rebuild dependant pages
        foreach my $f (@files) {
            next if $rendered{$f};
            my $p=pagename($f);
            if (exists $depends{$p}) {
                # only consider internal files
                # if the page explicitly depends on such files
                foreach my $file (@changed, $depends{$p}=~/internal\(/ ? @internal : ()) {
                    next if $f eq $file;
                    my $page=pagename($file);
                    if (pagespec_match($page, $depends{$p}, location => $p)) {
                        debug(sprintf(gettext("rendering %s, which depends on %s"), $f, $page));
                        render($f);
                        $rendered{$f}=1;
                        last;
                    }
                }
            }
        }
        
        # handle backlinks; if a page has added/removed links,
        # update the pages it links to
        my %linkchanged;
        foreach my $file (@changed) {
            my $page=pagename($file);
            
            if (exists $links{$page}) {
                foreach my $link (map { bestlink($page, $_) } @{$links{$page}}) {
                    if (length $link &&
                        (! exists $oldlinks{$page} ||
                         ! grep { bestlink($page, $_) eq $link } @{$oldlinks{$page}})) {
                        $linkchanged{$link}=1;
                    }
                }
            }
            if (exists $oldlinks{$page}) {
                foreach my $link (map { bestlink($page, $_) } @{$oldlinks{$page}}) {
                    if (length $link &&
                        (! exists $links{$page} || 
                         ! grep { bestlink($page, $_) eq $link } @{$links{$page}})) {
                        $linkchanged{$link}=1;
                    }
                }
            }
        }

        foreach my $link (keys %linkchanged) {
                my $linkfile=$pagesources{$link};
            if (defined $linkfile) {
                next if $rendered{$linkfile};
                debug(sprintf(gettext("rendering %s, to update its backlinks"), $linkfile));
                render($linkfile);
                $rendered{$linkfile}=1;
            }
        }
    }

    # remove no longer rendered files
    foreach my $src (keys %rendered) {
        my $page=pagename($src);
        foreach my $file (@{$oldrenderedfiles{$page}}) {
            if (! grep { $_ eq $file } @{$renderedfiles{$page}}) {
                debug(sprintf(gettext("removing %s, no longer rendered by %s"), $file, $page));
                prune($config{destdir}."/".$file);
            }
        }
    }

    if (@del) {
        run_hooks(delete => sub { shift->(@del) });
    }
    if (%rendered) {
        run_hooks(change => sub { shift->(keys %rendered) });
    }
}

sub commandline_render () {
    lockwiki();
    loadindex();
    unlockwiki();

    my $srcfile=possibly_foolish_untaint($config{render});
    my $file=$srcfile;
    $file=~s/\Q$config{srcdir}\E\/?//;

    my $type=pagetype($file);
    die sprintf(gettext("ikiwiki: cannot render %s"), $srcfile)."\n" unless defined $type;
    my $content=readfile($srcfile);
    my $page=pagename($file);
    $pagesources{$page}=$file;
    $content=filter($page, $page, $content);
    $content=preprocess($page, $page, $content);
    $content=linkify($page, $page, $content);
    $content=htmlize($page, $page, $type, $content);
    $pagemtime{$page}=(stat($srcfile))[9];
    $pagectime{$page}=$pagemtime{$page} if ! exists $pagectime{$page};

    print genpage($page, $content);
    exit 0;
}

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