1 files changed, 132 insertions, 0 deletions
diff --git a/scripts/Dpkg/Exit.pm b/scripts/Dpkg/Exit.pm
new file mode 100644
index 0000000..460b4ee
--- /dev/null
+++ b/scripts/Dpkg/Exit.pm
@@ -0,0 +1,132 @@
+# Copyright © 2002 Adam Heath <doogie@debian.org>
+# Copyright © 2012-2013 Guillem Jover <guillem@debian.org>
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+package Dpkg::Exit;
+
+use strict;
+use warnings;
+
+our $VERSION = '2.00';
+our @EXPORT_OK = qw(
+    push_exit_handler
+    pop_exit_handler
+    run_exit_handlers
+);
+
+use Exporter qw(import);
+
+my @handlers = ();
+
+=encoding utf8
+
+=head1 NAME
+
+Dpkg::Exit - program exit handlers
+
+=head1 DESCRIPTION
+
+The Dpkg::Exit module provides support functions to run handlers on exit.
+
+=head1 FUNCTIONS
+
+=over 4
+
+=item push_exit_handler($func)
+
+Register a code reference into the exit function handlers stack.
+
+=cut
+
+sub push_exit_handler {
+    my ($func) = shift;
+
+    _setup_exit_handlers() if @handlers == 0;
+    push @handlers, $func;
+}
+
+=item pop_exit_handler()
+
+Pop the last registered exit handler from the handlers stack.
+
+=cut
+
+sub pop_exit_handler {
+    _reset_exit_handlers() if @handlers == 1;
+    pop @handlers;
+}
+
+=item run_exit_handlers()
+
+Run the registered exit handlers.
+
+=cut
+
+sub run_exit_handlers {
+    while (my $handler = pop @handlers) {
+        $handler->();
+    }
+    _reset_exit_handlers();
+}
+
+sub _exit_handler {
+    run_exit_handlers();
+    exit(127);
+}
+
+my @SIGNAMES = qw(INT HUP QUIT);
+my %SIGOLD;
+
+sub _setup_exit_handlers
+{
+    foreach my $signame (@SIGNAMES) {
+        $SIGOLD{$signame} = $SIG{$signame};
+        $SIG{$signame} = \&_exit_handler;
+    }
+}
+
+sub _reset_exit_handlers
+{
+    foreach my $signame (@SIGNAMES) {
+        $SIG{$signame} = $SIGOLD{$signame};
+    }
+}
+
+END {
+    local $?;
+    run_exit_handlers();
+}
+
+=back
+
+=head1 CHANGES
+
+=head2 Version 2.00 (dpkg 1.20.0)
+
+Hide variable: @handlers.
+
+=head2 Version 1.01 (dpkg 1.17.2)
+
+New functions: push_exit_handler(), pop_exit_handler(), run_exit_handlers()
+
+Deprecated variable: @handlers
+
+=head2 Version 1.00 (dpkg 1.15.6)
+
+Mark the module as public.
+
+=cut
+
+1;