Current File : //usr/share/perl5/HTTP/Headers/ETag.pm
package HTTP::Headers::ETag;
use strict;
use warnings;
our $VERSION = '6.36';
require HTTP::Date;
require HTTP::Headers;
package
HTTP::Headers;
sub _etags
{
my $self = shift;
my $header = shift;
my @old = _split_etag_list($self->_header($header));
if (@_) {
$self->_header($header => join(", ", _split_etag_list(@_)));
}
wantarray ? @old : join(", ", @old);
}
sub etag { shift->_etags("ETag", @_); }
sub if_match { shift->_etags("If-Match", @_); }
sub if_none_match { shift->_etags("If-None-Match", @_); }
sub if_range {
# Either a date or an entity-tag
my $self = shift;
my @old = $self->_header("If-Range");
if (@_) {
my $new = shift;
if (!defined $new) {
$self->remove_header("If-Range");
}
elsif ($new =~ /^\d+$/) {
$self->_date_header("If-Range", $new);
}
else {
$self->_etags("If-Range", $new);
}
}
return unless defined(wantarray);
for (@old) {
my $t = HTTP::Date::str2time($_);
$_ = $t if $t;
}
wantarray ? @old : join(", ", @old);
}
# Split a list of entity tag values. The return value is a list
# consisting of one element per entity tag. Suitable for parsing
# headers like C<If-Match>, C<If-None-Match>. You might even want to
# use it on C<ETag> and C<If-Range> entity tag values, because it will
# normalize them to the common form.
#
# entity-tag = [ weak ] opaque-tag
# weak = "W/"
# opaque-tag = quoted-string
sub _split_etag_list
{
my(@val) = @_;
my @res;
for (@val) {
while (length) {
my $weak = "";
$weak = "W/" if s,^\s*[wW]/,,;
my $etag = "";
if (s/^\s*(\"[^\"\\]*(?:\\.[^\"\\]*)*\")//) {
push(@res, "$weak$1");
}
elsif (s/^\s*,//) {
push(@res, qq(W/"")) if $weak;
}
elsif (s/^\s*([^,\s]+)//) {
$etag = $1;
$etag =~ s/([\"\\])/\\$1/g;
push(@res, qq($weak"$etag"));
}
elsif (s/^\s+// || !length) {
push(@res, qq(W/"")) if $weak;
}
else {
die "This should not happen: '$_'";
}
}
}
@res;
}
1;
__END__
=pod
=encoding UTF-8
=head1 NAME
HTTP::Headers::ETag
=head1 VERSION
version 6.36
=head1 AUTHOR
Gisle Aas <gisle@activestate.com>
=head1 COPYRIGHT AND LICENSE
This software is copyright (c) 1994 by Gisle Aas.
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.
=cut
Mini Shell