package Tie::RefHash;
+use vars qw/$VERSION/;
+
+$VERSION = "1.34_01";
+
=head1 NAME
Tie::RefHash - use references as hash keys
first C<tie> the hash variable to this module. Normally, only the
keys of the tied hash itself are preserved as references; to use
references as keys in hashes-of-hashes, use Tie::RefHash::Nestable,
-included as part of Tie::Hash.
+included as part of Tie::RefHash.
It is implemented using the standard perl TIEHASH interface. Please
see the C<tie> entry in perlfunc(1) and perltie(1) for more information.
print ref($_), "\n";
}
+=head1 THREAD SUPPORT
+
+L<Tie::RefHash> fully supports threading using the C<CLONE> method.
+
+=head1 STORABLE SUPPORT
+
+L<Storable> hooks are provided for semantically correct serialization and
+cloning of tied refhashes.
+
+=head1 RELIC SUPPORT
+
+This version of Tie::RefHash seems to no longer work with 5.004. This has not
+been throughly investigated. Patches welcome ;-)
+
+=head1 MAINTAINER
+
+Yuval Kogman E<lt>nothingmuch@woobling.orgE<gt>
+
=head1 AUTHOR
Gurusamy Sarathy gsar@activestate.com
-=head1 VERSION
-
-Version 1.21 22 Jun 1999
+'Nestable' by Ed Avis ed@membled.com
=head1 SEE ALSO
=cut
-require 5.003_11;
use Tie::Hash;
+use vars '@ISA';
@ISA = qw(Tie::Hash);
use strict;
+use Carp qw/croak/;
+
+BEGIN {
+ # determine whether we need to take care of threads
+ use Config ();
+ my $usethreads = $Config::Config{usethreads}; # && exists $INC{"threads.pm"}
+ *_HAS_THREADS = $usethreads ? sub () { 1 } : sub () { 0 };
+ if ($usethreads) {
+ # The magic of taint tunneling means that we can't do this require in the
+ # same statement as the boolean check on $usethreads, as $usethreads is
+ # tainted.
+ require Scalar::Util;
+ }
+}
+
+BEGIN {
+ # create a refaddr function
+
+ if ( eval { require Scalar::Util; 1 } ) {
+ Scalar::Util->import("refaddr");
+ } else {
+ require overload;
+
+ *refaddr = sub {
+ if ( overload::StrVal($_[0]) =~ /\( 0x ([a-zA-Z0-9]+) \)$/x) {
+ return $1;
+ } else {
+ die "couldn't parse StrVal: " . overload::StrVal($_[0]);
+ }
+ };
+ }
+}
+
+my (@thread_object_registry, $count); # used by the CLONE method to rehash the keys after their refaddr changed
sub TIEHASH {
my $c = shift;
while (@_) {
$s->STORE(shift, shift);
}
+
+ if (_HAS_THREADS) {
+ # remember the object so that we can rekey it on CLONE
+ push @thread_object_registry, $s;
+ # but make this a weak reference, so that there are no leaks
+ Scalar::Util::weaken( $thread_object_registry[-1] );
+
+ if ( ++$count > 1000 ) {
+ # this ensures we don't fill up with a huge array dead weakrefs
+ @thread_object_registry = grep { defined } @thread_object_registry;
+ $count = 0;
+ }
+ }
+
return $s;
}
+my $storable_format_version = join("/", __PACKAGE__, "0.01");
+
+sub STORABLE_freeze {
+ my ( $self, $is_cloning ) = @_;
+ my ( $refs, $reg ) = @$self;
+ return ( $storable_format_version, [ values %$refs ], $reg );
+}
+
+sub STORABLE_thaw {
+ my ( $self, $is_cloning, $version, $refs, $reg ) = @_;
+ croak "incompatible versions of Tie::RefHash between freeze and thaw"
+ unless $version eq $storable_format_version;
+
+ @$self = ( {}, $reg );
+ $self->_reindex_keys( $refs );
+}
+
+sub CLONE {
+ my $pkg = shift;
+ # when the thread has been cloned all the objects need to be updated.
+ # dead weakrefs are undefined, so we filter them out
+ @thread_object_registry = grep { defined && do { $_->_reindex_keys; 1 } } @thread_object_registry;
+ $count = 0; # we just cleaned up
+}
+
+sub _reindex_keys {
+ my ( $self, $extra_keys ) = @_;
+ # rehash all the ref keys based on their new StrVal
+ %{ $self->[0] } = map { refaddr($_->[0]) => $_ } (values(%{ $self->[0] }), @{ $extra_keys || [] });
+}
+
sub FETCH {
my($s, $k) = @_;
if (ref $k) {
- if (defined $s->[0]{"$k"}) {
- $s->[0]{"$k"}[1];
+ my $kstr = refaddr($k);
+ if (defined $s->[0]{$kstr}) {
+ $s->[0]{$kstr}[1];
}
else {
undef;
sub STORE {
my($s, $k, $v) = @_;
if (ref $k) {
- $s->[0]{"$k"} = [$k, $v];
+ $s->[0]{refaddr($k)} = [$k, $v];
}
else {
$s->[1]{$k} = $v;
sub DELETE {
my($s, $k) = @_;
- (ref $k) ? delete($s->[0]{"$k"}) : delete($s->[1]{$k});
+ (ref $k)
+ ? (delete($s->[0]{refaddr($k)}) || [])->[1]
+ : delete($s->[1]{$k});
}
sub EXISTS {
my($s, $k) = @_;
- (ref $k) ? exists($s->[0]{"$k"}) : exists($s->[1]{$k});
+ (ref $k) ? exists($s->[0]{refaddr($k)}) : exists($s->[1]{$k});
}
sub FIRSTKEY {
my $s = shift;
- keys %{$s->[0]}; # reset iterator
- keys %{$s->[1]}; # reset iterator
- $s->[2] = 0;
+ keys %{$s->[0]}; # reset iterator
+ keys %{$s->[1]}; # reset iterator
+ $s->[2] = 0; # flag for iteration, see NEXTKEY
$s->NEXTKEY;
}
my ($k, $v);
if (!$s->[2]) {
if (($k, $v) = each %{$s->[0]}) {
- return $s->[0]{"$k"}[0];
+ return $v->[0];
}
else {
$s->[2] = 1;
}
package Tie::RefHash::Nestable;
-use vars '@ISA'; @ISA = qw(Tie::RefHash);
+use vars '@ISA';
+@ISA = 'Tie::RefHash';
sub STORE {
my($s, $k, $v) = @_;
https://perl5.git.perl.org / perl5.git / blobdiff