path: root/IkiWiki/Plugin/filecheck.pm

#!/usr/bin/perl
package IkiWiki::Plugin::filecheck;

use warnings;
use strict;
use IkiWiki 3.00;

my %units=(     # size in bytes
    B       => 1,
    byte        => 1,
    KB      => 2 ** 10,
    kilobyte    => 2 ** 10,
    K       => 2 ** 10,
    KB      => 2 ** 10,
    kilobyte    => 2 ** 10,
    M       => 2 ** 20,
    MB      => 2 ** 20,
    megabyte    => 2 ** 20,
    G       => 2 ** 30,
    GB      => 2 ** 30,
    gigabyte    => 2 ** 30,
    T       => 2 ** 40,
    TB      => 2 ** 40,
    terabyte    => 2 ** 40,
    P       => 2 ** 50,
    PB      => 2 ** 50,
    petabyte    => 2 ** 50,
    E       => 2 ** 60,
    EB      => 2 ** 60,
    exabyte     => 2 ** 60,
    Z       => 2 ** 70,
    ZB      => 2 ** 70,
    zettabyte   => 2 ** 70,
    Y       => 2 ** 80,
    YB      => 2 ** 80,
    yottabyte   => 2 ** 80,
    # ikiwiki, if you find you need larger data quantities, either modify
    # yourself to add them, or travel back in time to 2008 and kill me.
    #   -- Joey
);

sub import {
    hook(type => "getsetup", id => "filecheck",  call => \&getsetup);
}

sub getsetup () {
    return
        plugin => {
            safe => 1,
            rebuild => undef,
            section => "misc",
        },
}

sub parsesize ($) {
    my $size=shift;

    no warnings;
    my $base=$size+0; # force to number
    use warnings;
    foreach my $unit (sort keys %units) {
        if ($size=~/[0-9\s]\Q$unit\E$/i) {
            return $base * $units{$unit};
        }
    }
    return $base;
}

# This is provided for other plugins that want to convert back the other way.
sub humansize ($) {
    my $size=shift;

    foreach my $unit (reverse sort { $units{$a} <=> $units{$b} || $b cmp $a } keys %units) {
        if ($size / $units{$unit} > 0.25) {
            return (int($size / $units{$unit} * 10)/10).$unit;
        }
    }
    return $size; # near zero, or negative
}

package IkiWiki::PageSpec;

sub match_maxsize ($$;@) {
    my $page=shift;
    my $maxsize=eval{IkiWiki::Plugin::filecheck::parsesize(shift)};
    if ($@) {
        return IkiWiki::ErrorReason->new("unable to parse maxsize (or number too large)");
    }

    my %params=@_;
    my $file=exists $params{file} ? $params{file} : IkiWiki::srcfile($IkiWiki::pagesources{$page});
    if (! defined $file) {
        return IkiWiki::ErrorReason->new("file does not exist");
    }

    if (-s $file > $maxsize) {
        return IkiWiki::FailReason->new("file too large (".(-s $file)." >  $maxsize)");
    }
    else {
        return IkiWiki::SuccessReason->new("file not too large");
    }
}

sub match_minsize ($$;@) {
    my $page=shift;
    my $minsize=eval{IkiWiki::Plugin::filecheck::parsesize(shift)};
    if ($@) {
        return IkiWiki::ErrorReason->new("unable to parse minsize (or number too large)");
    }

    my %params=@_;
    my $file=exists $params{file} ? $params{file} : IkiWiki::srcfile($IkiWiki::pagesources{$page});
    if (! defined $file) {
        return IkiWiki::ErrorReason->new("file does not exist");
    }

    if (-s $file < $minsize) {
        return IkiWiki::FailReason->new("file too small");
    }
    else {
        return IkiWiki::SuccessReason->new("file not too small");
    }
}

sub match_mimetype ($$;@) {
    my $page=shift;
    my $wanted=shift;

    my %params=@_;
    my $file=exists $params{file} ? $params{file} : IkiWiki::srcfile($IkiWiki::pagesources{$page});
    if (! defined $file) {
        return IkiWiki::ErrorReason->new("file does not exist");
    }

    # Get the mime type.
    #
    # First, try File::Mimeinfo. This is fast, but doesn't recognise
    # all files.
    eval q{use File::MimeInfo::Magic};
    my $mimeinfo_ok=! $@;
    my $mimetype;
    if ($mimeinfo_ok) {
        my $mimetype=File::MimeInfo::Magic::magic($file);
    }

    # Fall back to using file, which has a more complete
    # magic database.
    if (! defined $mimetype) {
        open(my $file_h, "-|", "file", "-bi", $file);
        $mimetype=<$file_h>;
        chomp $mimetype;
        close $file_h;
    }
    if (! defined $mimetype || $mimetype !~s /;.*//) {
        # Fall back to default value.
        $mimetype=File::MimeInfo::Magic::default($file)
            if $mimeinfo_ok;
        if (! defined $mimetype) {
            $mimetype="unknown";
        }
    }

    my $regexp=IkiWiki::glob2re($wanted);
    if ($mimetype!~$regexp) {
        return IkiWiki::FailReason->new("file MIME type is $mimetype, not $wanted");
    }
    else {
        return IkiWiki::SuccessReason->new("file MIME type is $mimetype");
    }
}

sub match_virusfree ($$;@) {
    my $page=shift;
    my $wanted=shift;

    my %params=@_;
    my $file=exists $params{file} ? $params{file} : IkiWiki::srcfile($IkiWiki::pagesources{$page});
    if (! defined $file) {
        return IkiWiki::ErrorReason->new("file does not exist");
    }

    if (! exists $IkiWiki::config{virus_checker} ||
        ! length $IkiWiki::config{virus_checker}) {
        return IkiWiki::ErrorReason->new("no virus_checker configured");
    }

    # The file needs to be fed into the virus checker on stdin,
    # because the file is not world-readable, and if clamdscan is
    # used, clamd would fail to read it.
    eval q{use IPC::Open2};
    error($@) if $@;
    open (IN, "<", $file) || return IkiWiki::ErrorReason->new("failed to read file");
    binmode(IN);
    my $sigpipe=0;
    $SIG{PIPE} = sub { $sigpipe=1 };
    my $pid=open2(\*CHECKER_OUT, "<&IN", $IkiWiki::config{virus_checker}); 
    my $reason=<CHECKER_OUT>;
    chomp $reason;
    1 while (<CHECKER_OUT>);
    close(CHECKER_OUT);
    waitpid $pid, 0;
    $SIG{PIPE}="DEFAULT";
    if ($sigpipe || $?) {
        if (! length $reason) {
            $reason="virus checker $IkiWiki::config{virus_checker}; failed with no output";
        }
        return IkiWiki::FailReason->new("file seems to contain a virus ($reason)");
    }
    else {
        return IkiWiki::SuccessReason->new("file seems virusfree ($reason)");
    }
}

sub match_ispage ($$;@) {
    my $filename=shift;

    if (defined IkiWiki::pagetype($filename)) {
        return IkiWiki::SuccessReason->new("file is a wiki page");
    }
    else {
        return IkiWiki::FailReason->new("file is not a wiki page");
    }
}