/usr/share/perl5/Devel/GlobalDestruction.pm is in libdevel-globaldestruction-perl 0.06-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 | package Devel::GlobalDestruction;
use strict;
use warnings;
our $VERSION = '0.06';
use Sub::Exporter -setup => {
exports => [ qw(in_global_destruction) ],
groups => { default => [ -all ] },
};
# we run 5.14+ - everything is in core
#
if (defined ${^GLOBAL_PHASE}) {
eval 'sub in_global_destruction () { ${^GLOBAL_PHASE} eq q[DESTRUCT] }';
}
# try to load the xs version if it was compiled
#
elsif (eval {
require XSLoader;
XSLoader::load(__PACKAGE__, $VERSION);
1;
}) {
# the eval already installed everything, nothing to do
}
# Not core nor XS
#
else {
# SpeedyCGI runs END blocks every cycle but somehow keeps object instances
# hence DIAF
die("The pure-perl version of @{[__PACKAGE__]} can not function correctly under CGI::SpeedyCGI. "
. "Please ensure you have a working compiler, and reinstall @{[__PACKAGE__]} to enable the XS "
. "codepath.\n"
) if $CGI::SpeedyCGI::i_am_speedy;
eval <<'PP_IGD' or die $@;
my ($in_global_destruction, $before_is_installed);
sub in_global_destruction { $in_global_destruction }
# This block will fire towards the end of the program execution
# Since there is no way for us to generate an END which will execute *last*
# this is *NOT 100% INCOMPATIBLE* with XS/${^GLOBAL_PHASE}. We *may* end up
# with a true in_gloal_destruction() in the middle of another END block
# There are no practical cases where this matters.
#
END {
$in_global_destruction = 1;
}
# threads do not execute the global ENDs (it would be stupid). However
# one can register a new END via simple string eval within a thread, and
# achieve the same result. A logical place to do this would be CLONE, which
# is claimed to run in the context of the new thread. However this does
# not really seem to be the case - any END evaled in a CLONE is ignored :(
# Hence blatantly hooking threads::create
#
if ($INC{'threads.pm'}) {
my $orig_create = threads->can('create');
no warnings 'redefine';
*threads::create = sub {
{ local $@; eval 'END { $in_global_destruction = 1 }' };
goto $orig_create;
};
$before_is_installed = 1;
}
# just in case threads got loaded after us (silly)
sub CLONE {
unless ($before_is_installed) {
require Carp;
Carp::croak("You must load the 'threads' module before @{[ __PACKAGE__ ]}");
}
}
1; # keep eval happy
PP_IGD
}
1; # keep require happy
__END__
=head1 NAME
Devel::GlobalDestruction - Expose the flag which marks global
destruction.
=head1 SYNOPSIS
package Foo;
use Devel::GlobalDestruction;
use namespace::clean; # to avoid having an "in_global_destruction" method
sub DESTROY {
return if in_global_destruction;
do_something_a_little_tricky();
}
=head1 DESCRIPTION
Perl's global destruction is a little tricky to deal with WRT finalizers
because it's not ordered and objects can sometimes disappear.
Writing defensive destructors is hard and annoying, and usually if global
destruction is happenning you only need the destructors that free up non
process local resources to actually execute.
For these constructors you can avoid the mess by simply bailing out if global
destruction is in effect.
=head1 EXPORTS
This module uses L<Sub::Exporter> so the exports may be renamed, aliased, etc.
=over 4
=item in_global_destruction
Returns true if the interpreter is in global destruction. In perl 5.14+, this
returns C<${^GLOBAL_PHASE} eq 'DESTRUCT'>, and on earlier perls, it returns the
current value of C<PL_dirty>.
=back
=head1 AUTHORS
Yuval Kogman E<lt>nothingmuch@woobling.orgE<gt>
Florian Ragwitz E<lt>rafl@debian.orgE<gt>
Jesse Luehrs E<lt>doy@tozt.netE<gt>
Peter Rabbitson E<lt>ribasushi@cpan.orgE<gt>
=head1 COPYRIGHT
Copyright (c) 2008 Yuval Kogman. All rights reserved
This program is free software; you can redistribute
it and/or modify it under the same terms as Perl itself.
=cut
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