#------------------------------------------------------------------------------
# File: HTML.pm
#
# Description: Read HTML meta information
#
# Revisions: 01/30/2007 - P. Harvey Created
#
# References: 1) http://www.w3.org/TR/html4/
# 2) http://www.daisy.org/publications/specifications/daisy_202.html
# 3) http://vancouver-webpages.com/META/metatags.detail.html
# 4) http://www.html-reference.com/META.htm
#------------------------------------------------------------------------------
package Image::ExifTool::HTML;
use strict;
use vars qw($VERSION @ISA @EXPORT_OK);
use Image::ExifTool qw(:DataAccess :Utils);
use Image::ExifTool::PostScript;
use Image::ExifTool::XMP qw(EscapeXML UnescapeXML);
require Exporter;
$VERSION = '1.16';
@ISA = qw(Exporter);
@EXPORT_OK = qw(EscapeHTML UnescapeHTML);
sub SetHTMLCharset($$);
# convert HTML charset (lower case) to ExifTool Charset name
my %htmlCharset = (
macintosh => 'MacRoman',
'iso-8859-1' => 'Latin',
'utf-8' => 'UTF8',
'windows-1252' => 'Latin',
);
# HTML 4 character entity references
my %entityNum = (
'quot' => 34, 'eth' => 240, 'lsquo' => 8216,
'amp' => 38, 'ntilde' => 241, 'rsquo' => 8217,
'apos' => 39, 'ograve' => 242, 'sbquo' => 8218,
'lt' => 60, 'oacute' => 243, 'ldquo' => 8220,
'gt' => 62, 'ocirc' => 244, 'rdquo' => 8221,
'nbsp' => 160, 'otilde' => 245, 'bdquo' => 8222,
'iexcl' => 161, 'ouml' => 246, 'dagger' => 8224,
'cent' => 162, 'divide' => 247, 'Dagger' => 8225,
'pound' => 163, 'oslash' => 248, 'bull' => 8226,
'curren' => 164, 'ugrave' => 249, 'hellip' => 8230,
'yen' => 165, 'uacute' => 250, 'permil' => 8240,
'brvbar' => 166, 'ucirc' => 251, 'prime' => 8242,
'sect' => 167, 'uuml' => 252, 'Prime' => 8243,
'uml' => 168, 'yacute' => 253, 'lsaquo' => 8249,
'copy' => 169, 'thorn' => 254, 'rsaquo' => 8250,
'ordf' => 170, 'yuml' => 255, 'oline' => 8254,
'laquo' => 171, 'OElig' => 338, 'frasl' => 8260,
'not' => 172, 'oelig' => 339, 'euro' => 8364,
'shy' => 173, 'Scaron' => 352, 'image' => 8465,
'reg' => 174, 'scaron' => 353, 'weierp' => 8472,
'macr' => 175, 'Yuml' => 376, 'real' => 8476,
'deg' => 176, 'fnof' => 402, 'trade' => 8482,
'plusmn' => 177, 'circ' => 710, 'alefsym'=> 8501,
'sup2' => 178, 'tilde' => 732, 'larr' => 8592,
'sup3' => 179, 'Alpha' => 913, 'uarr' => 8593,
'acute' => 180, 'Beta' => 914, 'rarr' => 8594,
'micro' => 181, 'Gamma' => 915, 'darr' => 8595,
'para' => 182, 'Delta' => 916, 'harr' => 8596,
'middot' => 183, 'Epsilon'=> 917, 'crarr' => 8629,
'cedil' => 184, 'Zeta' => 918, 'lArr' => 8656,
'sup1' => 185, 'Eta' => 919, 'uArr' => 8657,
'ordm' => 186, 'Theta' => 920, 'rArr' => 8658,
'raquo' => 187, 'Iota' => 921, 'dArr' => 8659,
'frac14' => 188, 'Kappa' => 922, 'hArr' => 8660,
'frac12' => 189, 'Lambda' => 923, 'forall' => 8704,
'frac34' => 190, 'Mu' => 924, 'part' => 8706,
'iquest' => 191, 'Nu' => 925, 'exist' => 8707,
'Agrave' => 192, 'Xi' => 926, 'empty' => 8709,
'Aacute' => 193, 'Omicron'=> 927, 'nabla' => 8711,
'Acirc' => 194, 'Pi' => 928, 'isin' => 8712,
'Atilde' => 195, 'Rho' => 929, 'notin' => 8713,
'Auml' => 196, 'Sigma' => 931, 'ni' => 8715,
'Aring' => 197, 'Tau' => 932, 'prod' => 8719,
'AElig' => 198, 'Upsilon'=> 933, 'sum' => 8721,
'Ccedil' => 199, 'Phi' => 934, 'minus' => 8722,
'Egrave' => 200, 'Chi' => 935, 'lowast' => 8727,
'Eacute' => 201, 'Psi' => 936, 'radic' => 8730,
'Ecirc' => 202, 'Omega' => 937, 'prop' => 8733,
'Euml' => 203, 'alpha' => 945, 'infin' => 8734,
'Igrave' => 204, 'beta' => 946, 'ang' => 8736,
'Iacute' => 205, 'gamma' => 947, 'and' => 8743,
'Icirc' => 206, 'delta' => 948, 'or' => 8744,
'Iuml' => 207, 'epsilon'=> 949, 'cap' => 8745,
'ETH' => 208, 'zeta' => 950, 'cup' => 8746,
'Ntilde' => 209, 'eta' => 951, 'int' => 8747,
'Ograve' => 210, 'theta' => 952, 'there4' => 8756,
'Oacute' => 211, 'iota' => 953, 'sim' => 8764,
'Ocirc' => 212, 'kappa' => 954, 'cong' => 8773,
'Otilde' => 213, 'lambda' => 955, 'asymp' => 8776,
'Ouml' => 214, 'mu' => 956, 'ne' => 8800,
'times' => 215, 'nu' => 957, 'equiv' => 8801,
'Oslash' => 216, 'xi' => 958, 'le' => 8804,
'Ugrave' => 217, 'omicron'=> 959, 'ge' => 8805,
'Uacute' => 218, 'pi' => 960, 'sub' => 8834,
'Ucirc' => 219, 'rho' => 961, 'sup' => 8835,
'Uuml' => 220, 'sigmaf' => 962, 'nsub' => 8836,
'Yacute' => 221, 'sigma' => 963, 'sube' => 8838,
'THORN' => 222, 'tau' => 964, 'supe' => 8839,
'szlig' => 223, 'upsilon'=> 965, 'oplus' => 8853,
'agrave' => 224, 'phi' => 966, 'otimes' => 8855,
'aacute' => 225, 'chi' => 967, 'perp' => 8869,
'acirc' => 226, 'psi' => 968, 'sdot' => 8901,
'atilde' => 227, 'omega' => 969, 'lceil' => 8968,
'auml' => 228, 'thetasym'=>977, 'rceil' => 8969,
'aring' => 229, 'upsih' => 978, 'lfloor' => 8970,
'aelig' => 230, 'piv' => 982, 'rfloor' => 8971,
'ccedil' => 231, 'ensp' => 8194, 'lang' => 9001,
'egrave' => 232, 'emsp' => 8195, 'rang' => 9002,
'eacute' => 233, 'thinsp' => 8201, 'loz' => 9674,
'ecirc' => 234, 'zwnj' => 8204, 'spades' => 9824,
'euml' => 235, 'zwj' => 8205, 'clubs' => 9827,
'igrave' => 236, 'lrm' => 8206, 'hearts' => 9829,
'iacute' => 237, 'rlm' => 8207, 'diams' => 9830,
'icirc' => 238, 'ndash' => 8211,
'iuml' => 239, 'mdash' => 8212,
);
my %entityName; # look up entity names by number (built as necessary)
# HTML info
# (tag ID's are case insensitive and must be all lower case in tables)
%Image::ExifTool::HTML::Main = (
GROUPS => { 2 => 'Document' },
NOTES => q{
Meta information extracted from the header of HTML and XHTML files. This is
a mix of information found in the C elements, C element, and the
C element.
},
dc => {
Name => 'DC',
SubDirectory => { TagTable => 'Image::ExifTool::HTML::dc' },
},
ncc => {
Name => 'NCC',
SubDirectory => { TagTable => 'Image::ExifTool::HTML::ncc' },
},
prod => {
Name => 'Prod',
SubDirectory => { TagTable => 'Image::ExifTool::HTML::prod' },
},
vw96 => {
Name => 'VW96',
SubDirectory => { TagTable => 'Image::ExifTool::HTML::vw96' },
},
'http-equiv' => {
Name => 'HTTP-equiv',
SubDirectory => { TagTable => 'Image::ExifTool::HTML::equiv' },
},
o => {
Name => 'Office',
SubDirectory => { TagTable => 'Image::ExifTool::HTML::Office' },
},
abstract => { },
author => { },
classification => { },
'content-language'=>{ Name => 'ContentLanguage' },
copyright => { },
description => { },
distribution => { },
'doc-class' => { Name => 'DocClass' },
'doc-rights' => { Name => 'DocRights' },
'doc-type' => { Name => 'DocType' },
formatter => { },
generator => { },
generatorversion=> { Name => 'GeneratorVersion' },
googlebot => { Name => 'GoogleBot' },
keywords => { List => 1 },
mssmarttagspreventparsing => { Name => 'NoMSSmartTags' },
originator => { },
owner => { },
progid => { Name => 'ProgID' },
rating => { },
refresh => { },
'resource-type' => { Name => 'ResourceType' },
'revisit-after' => { Name => 'RevisitAfter' },
robots => { List => 1 },
title => { Notes => "the only extracted tag which isn't from an HTML META element" },
);
# ref 2
%Image::ExifTool::HTML::dc = (
GROUPS => { 1 => 'HTML-dc', 2 => 'Document' },
NOTES => 'Dublin Core schema tags (also used in XMP).',
contributor => { Groups => { 2 => 'Author' }, List => 'Bag' },
coverage => { },
creator => { Groups => { 2 => 'Author' }, List => 'Seq' },
date => {
Groups => { 2 => 'Time' },
List => 'Seq',
PrintConv => '$self->ConvertDateTime($val)',
},
description => { },
'format' => { },
identifier => { },
language => { List => 'Bag' },
publisher => { Groups => { 2 => 'Author' }, List => 'Bag' },
relation => { List => 'Bag' },
rights => { Groups => { 2 => 'Author' } },
source => { Groups => { 2 => 'Author' } },
subject => { List => 'Bag' },
title => { },
type => { List => 'Bag' },
);
# ref 2
%Image::ExifTool::HTML::ncc = (
GROUPS => { 1 => 'HTML-ncc', 2 => 'Document' },
charset => { Name => 'CharacterSet' }, # name changed to avoid conflict with -charset option
depth => { },
files => { },
footnotes => { },
generator => { },
kbytesize => { Name => 'KByteSize' },
maxpagenormal => { Name => 'MaxPageNormal' },
multimediatype => { Name => 'MultimediaType' },
narrator => { },
pagefront => { Name => 'PageFront' },
pagenormal => { Name => 'PageNormal' },
pagespecial => { Name => 'PageSpecial' },
prodnotes => { Name => 'ProdNotes' },
producer => { },
produceddate => { Name => 'ProducedDate', Groups => { 2 => 'Time' } }, # YYYY-mm-dd
revision => { },
revisiondate => { Name => 'RevisionDate', Groups => { 2 => 'Time' } },
setinfo => { Name => 'SetInfo' },
sidebars => { },
sourcedate => { Name => 'SourceDate', Groups => { 2 => 'Time' } },
sourceedition => { Name => 'SourceEdition' },
sourcepublisher => { Name => 'SourcePublisher' },
sourcerights => { Name => 'SourceRights' },
sourcetitle => { Name => 'SourceTitle' },
tocitems => { Name => 'TOCItems' },
totaltime => { Name => 'Duration' }, # HH:MM:SS
);
# ref 3
%Image::ExifTool::HTML::vw96 = (
GROUPS => { 1 => 'HTML-vw96', 2 => 'Document' },
objecttype => { Name => 'ObjectType' },
);
# ref 2
%Image::ExifTool::HTML::prod = (
GROUPS => { 1 => 'HTML-prod', 2 => 'Document' },
reclocation => { Name => 'RecLocation' },
recengineer => { Name => 'RecEngineer' },
);
# ref 3/4
%Image::ExifTool::HTML::equiv = (
GROUPS => { 1 => 'HTTP-equiv', 2 => 'Document' },
NOTES => 'These tags have a family 1 group name of "HTTP-equiv".',
'cache-control' => { Name => 'CacheControl' },
'content-disposition' => { Name => 'ContentDisposition' },
'content-language' => { Name => 'ContentLanguage' },
'content-script-type' => { Name => 'ContentScriptType' },
'content-style-type' => { Name => 'ContentStyleType' },
# note: setting the HTMLCharset like this will miss any tags which come earlier
'content-type' => { Name => 'ContentType', RawConv => \&SetHTMLCharset },
'default-style' => { Name => 'DefaultStyle' },
expires => { },
'ext-cache' => { Name => 'ExtCache' },
imagetoolbar => { Name => 'ImageToolbar' },
lotus => { },
'page-enter' => { Name => 'PageEnter' },
'page-exit' => { Name => 'PageExit' },
'pics-label' => { Name => 'PicsLabel' },
pragma => { },
refresh => { },
'reply-to' => { Name => 'ReplyTo' },
'set-cookie' => { Name => 'SetCookie' },
'site-enter' => { Name => 'SiteEnter' },
'site-exit' => { Name => 'SiteExit' },
vary => { },
'window-target' => { Name => 'WindowTarget' },
);
# MS Office namespace (ref PH)
%Image::ExifTool::HTML::Office = (
GROUPS => { 1 => 'HTML-office', 2 => 'Document' },
NOTES => 'Tags written by Microsoft Office applications.',
Subject => { },
Author => { Groups => { 2 => 'Author' } },
Keywords => { },
Description => { },
Template => { },
LastAuthor => { Groups => { 2 => 'Author' } },
Revision => { Name => 'RevisionNumber' },
TotalTime => { Name => 'TotalEditTime', PrintConv => 'ConvertTimeSpan($val, 60)' },
Created => {
Name => 'CreateDate',
Groups => { 2 => 'Time' },
ValueConv => 'Image::ExifTool::XMP::ConvertXMPDate($val)',
PrintConv => '$self->ConvertDateTime($val)',
},
LastSaved => {
Name => 'ModifyDate',
Groups => { 2 => 'Time' },
ValueConv => 'Image::ExifTool::XMP::ConvertXMPDate($val)',
PrintConv => '$self->ConvertDateTime($val)',
},
LastSaved => {
Name => 'ModifyDate',
Groups => { 2 => 'Time' },
ValueConv => 'Image::ExifTool::XMP::ConvertXMPDate($val)',
PrintConv => '$self->ConvertDateTime($val)',
},
LastPrinted => {
Name => 'LastPrinted',
Groups => { 2 => 'Time' },
ValueConv => 'Image::ExifTool::XMP::ConvertXMPDate($val)',
PrintConv => '$self->ConvertDateTime($val)',
},
Pages => { },
Words => { },
Characters => { },
Category => { },
Manager => { },
Company => { },
Lines => { },
Paragraphs => { },
CharactersWithSpaces => { },
Version => { Name => 'RevisionNumber' },
);
#------------------------------------------------------------------------------
# Set HTMLCharset member based on content type
# Inputs: 0) content type string, 1) ExifTool ref
# Returns: original string
sub SetHTMLCharset($$)
{
my ($val, $et) = @_;
$$et{HTMLCharset} = $htmlCharset{lc $1} if $val =~ /charset=['"]?([-\w]+)/;
return $val;
}
#------------------------------------------------------------------------------
# Convert single UTF-8 character to HTML character reference
# Inputs: 0) UTF-8 character sequence
# Returns: HTML character reference (eg. """);
# Note: Must be called via EscapeHTML to load name lookup
sub EscapeChar($)
{
my $ch = shift;
my $val;
if ($] < 5.006001) {
($val) = Image::ExifTool::UnpackUTF8($ch);
} else {
# the meaning of "U0" is reversed as of Perl 5.10.0!
($val) = unpack($] < 5.010000 ? 'U0U' : 'C0U', $ch);
}
return '?' unless defined $val;
return "&$entityName{$val};" if $entityName{$val};
return sprintf('&#x%x;',$val);
}
#------------------------------------------------------------------------------
# Escape any special characters for HTML
# Inputs: 0) string to be escaped, 1) optional string encoding (default 'UTF8')
# Returns: escaped string
sub EscapeHTML($;$)
{
my ($str, $enc) = @_;
# escape XML characters
$str = EscapeXML($str);
# escape other special characters if they exist
if ($str =~ /[\x80-\xff]/) {
# generate entity name lookup if necessary
unless (%entityName) {
local $_;
foreach (keys %entityNum) {
$entityName{$entityNum{$_}} = $_;
}
delete $entityName{39}; # 'apos' is not valid HTML
}
# suppress warnings
local $SIG{'__WARN__'} = sub { 1 };
if ($enc and $enc ne 'UTF8') {
$str = Image::ExifTool::Decode(undef, $str, $enc, undef, 'UTF8');
$str =~ s/([\xc2-\xf7][\x80-\xbf]+)/EscapeChar($1)/sge;
$str = Image::ExifTool::Decode(undef, $str, 'UTF8', undef, $enc);
} else {
# escape any non-ascii characters for HTML
$str =~ s/([\xc2-\xf7][\x80-\xbf]+)/EscapeChar($1)/sge;
}
}
return $str;
}
#------------------------------------------------------------------------------
# Unescape all HTML character references
# Inputs: 0) string to be unescaped, 1) optional string encoding (default 'UTF8')
# Returns: unescaped string
sub UnescapeHTML($;$)
{
my ($str, $enc) = @_;
return UnescapeXML($str, \%entityNum, $enc);
}
#------------------------------------------------------------------------------
# Extract information from a HTML file
# Inputs: 0) ExifTool object reference, 1) DirInfo reference
# Returns: 1 on success, 0 if this wasn't a valid HTML file
sub ProcessHTML($$)
{
my ($et, $dirInfo) = @_;
my $raf = $$dirInfo{RAF};
my $buff;
# validate HTML or XHTML file
$raf->Read($buff, 256) or return 0;
$buff =~ /^(\xef\xbb\xbf)?\s*<(!DOCTYPE\s+HTML|HTML|\?xml)/i or return 0;
$buff =~ /<(!DOCTYPE\s+)?HTML/i or return 0 if $2 eq '?xml';
$et->SetFileType();
$raf->Seek(0,0) or $et->Warn('Seek error'), return 1;
local $/ = Image::ExifTool::PostScript::GetInputRecordSeparator($raf);
$/ or $et->Warn('Invalid HTML data'), return 1;
# extract header information
my $doc;
while ($raf->ReadLine($buff)) {
if (not defined $doc) {
# look for 'head' element
next unless $buff =~ /<head\b/ig;
$doc = substr($buff, pos($buff));
next;
}
$doc .= $buff;
last if $buff =~ m{</head>}i;
}
return 1 unless defined $doc;
# process all elements in header
my $tagTablePtr = GetTagTable('Image::ExifTool::HTML::Main');
for (;;) {
last unless $doc =~ m{<([\w:.-]+)(.*?)>}sg;
my ($tagName, $attrs) = ($1, $2);
my $tag = lc($tagName);
my ($val, $grp);
if ($attrs =~ m{/$}) { # self-contained XHTML tags end in '/>'
$val = '';
} else {
# look for element close
my $pos = pos($doc);
my $close = "</$tagName>";
# the following doesn't work on Solaris Perl 5.6.1 due to Perl bug:
# if ($doc =~ m{(.*?)</$tagName>}sg) {
# $val = $1;
if ($doc =~ m{$close}sg) {
$val = substr($doc, $pos, pos($doc)-$pos-length($close));
} else {
pos($doc) = $pos;
next unless $tag eq 'meta'; # META tags don't need to be closed
$val = '';
}
}
my $table = $tagTablePtr;
if ($tag eq 'meta') {
# parse HTML META element
undef $tag;
# tag name is in NAME or HTTP-EQUIV attribute
if ($attrs =~ /\bname\s*=\s*['"]?([\w:.-]+)/si) {
$tagName = $1;
} elsif ($attrs =~ /\bhttp-equiv\s*=\s*['"]?([\w:.-]+)/si) {
$tagName = "HTTP-equiv.$1";
} else {
next; # no name
}
$tag = lc($tagName) or next;
# tag value is in CONTENT attribute
if ($attrs =~ /\bcontent\s*=\s*(['"])(.*?)\1/si or
$attrs =~ /\bcontent\s*=\s*(['"]?)([\w:.-]+)/si)
{
$val = $2;
} else {
next unless length $val;
}
# isolate group name (separator is '.' in HTML, but ':' in ref 2)
if ($tag =~ /^([\w-]+)[:.]([\w-]+)/) {
($grp, $tag) = ($1, $2);
my $tagInfo = $et->GetTagInfo($tagTablePtr, $grp);
if ($tagInfo and $$tagInfo{SubDirectory}) {
$table = GetTagTable($tagInfo->{SubDirectory}->{TagTable});
} else {
$tag = "$grp.$tag";
}
}
} elsif ($tag eq 'xml') {
$et->VPrint(0, "Parsing XML\n");
# parse XML tags (quick-and-dirty)
my $xml = $val;
while ($xml =~ /<([\w-]+):([\w-]+)(\s.*?)?>([^<]*?)<\/\1:\2>/g) {
($grp, $tag, $val) = ($1, $2, $4);
my $tagInfo = $et->GetTagInfo($tagTablePtr, $grp);
next unless $tagInfo and $$tagInfo{SubDirectory};
$table = GetTagTable($tagInfo->{SubDirectory}->{TagTable});
unless ($$table{$tag}) {
my $name = ucfirst $tag;
$name =~ s/_x([0-9a-f]{4})_/chr(hex($1))/gie; # convert hex codes
$name =~ s/\s(.)/\U$1/g; # capitalize all words in tag name
$name =~ tr/-_a-zA-Z0-9//dc; # remove illegal characters (also hex code wide chars)
AddTagToTable($table, $tag, { Name => $name });
$et->VPrint(0, " [adding $tag '${name}']\n");
}
$val = $et->Decode($val, $$et{HTMLCharset}) if $$et{HTMLCharset};
$et->HandleTag($table, $tag, UnescapeXML($val));
}
next;
} else {
# the only other element we process is TITLE
next unless $tag eq 'title';
}
unless ($$table{$tag}) {
my $name = $tagName;
$name =~ s/\W+(\w)/\u$1/sg;
my $info = { Name => $name, Groups => { 0 => 'HTML' } };
$info->{Groups}->{1} = ($grp eq 'http-equiv' ? 'HTTP-equiv' : "HTML-$grp") if $grp;
AddTagToTable($table, $tag, $info);
$et->VPrint(0, " [adding $tag '${tagName}']\n");
}
# recode if necessary
$val = $et->Decode($val, $$et{HTMLCharset}) if $$et{HTMLCharset};
$val =~ s{\s*$/\s*}{ }sg; # replace linefeeds and indenting spaces
$val = UnescapeHTML($val); # unescape HTML character references
$et->HandleTag($table, $tag, $val);
}
return 1;
}
1; # end
__END__
=head1 NAME
Image::ExifTool::HTML - Read HTML meta information
=head1 SYNOPSIS
This module is used by Image::ExifTool
=head1 DESCRIPTION
This module contains routines required by Image::ExifTool to extract
meta information from HTML documents.
=head1 AUTHOR
Copyright 2003-2023, Phil Harvey (philharvey66 at gmail.com)
This library is free software; you can redistribute it and/or modify it
under the same terms as Perl itself.
=head1 REFERENCES
=over 4
=item L<http://www.w3.org/TR/html4/>
=item L<http://www.daisy.org/publications/specifications/daisy_202.html>
=item L<http://vancouver-webpages.com/META/metatags.detail.html>
=item L<http://www.html-reference.com/META.htm>
=back
=head1 SEE ALSO
L<Image::ExifTool::TagNames/HTML Tags>,
L<Image::ExifTool(3pm)|Image::ExifTool>
=cut