Edit: /usr/share/perl5/Dpkg/Lock.pm (1919B)
# Copyright © 2011 Raphaël Hertzog
# Copyright © 2012 Guillem Jover
#
# 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 .
package Dpkg::Lock;
use strict;
use warnings;
our $VERSION = '0.01';
our @EXPORT = qw(
file_lock
);
use Exporter qw(import);
use Fcntl qw(:flock);
use Dpkg::Gettext;
use Dpkg::ErrorHandling;
sub file_lock($$) {
my ($fh, $filename) = @_;
# A strict dependency on libfile-fcntllock-perl being it an XS module,
# and dpkg-dev indirectly making use of it, makes building new perl
# package which bump the perl ABI impossible as these packages cannot
# be installed alongside.
eval q{
pop @INC if $INC[-1] eq '.';
use File::FcntlLock;
};
if ($@) {
# On Linux systems the flock() locks get converted to file-range
# locks on NFS mounts.
if ($^O ne 'linux') {
warning(g_('File::FcntlLock not available; using flock which is not NFS-safe'));
}
flock($fh, LOCK_EX)
or syserr(g_('failed to get a write lock on %s'), $filename);
} else {
eval q{
my $fs = File::FcntlLock->new(l_type => F_WRLCK);
$fs->lock($fh, F_SETLKW)
or syserr(g_('failed to get a write lock on %s'), $filename);
}
}
}
1;