mozilla-history/config/mozLock.pm

131 строка
3.7 KiB
Perl

#
# ***** BEGIN LICENSE BLOCK *****
# Version: MPL 1.1/GPL 2.0/LGPL 2.1
#
# The contents of this file are subject to the Mozilla Public License Version
# 1.1 (the "License"); you may not use this file except in compliance with
# the License. You may obtain a copy of the License at
# http://www.mozilla.org/MPL/
#
# Software distributed under the License is distributed on an "AS IS" basis,
# WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
# for the specific language governing rights and limitations under the
# License.
#
# The Original Code is mozilla.org code.
#
# The Initial Developer of the Original Code is
# Netscape Communications Corporation.
# Portions created by the Initial Developer are Copyright (C) 2001
# the Initial Developer. All Rights Reserved.
#
# Contributor(s):
# Christopher Seawood <cls@seawood.org>
#
# Alternatively, the contents of this file may be used under the terms of
# either of the GNU General Public License Version 2 or later (the "GPL"),
# or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
# in which case the provisions of the GPL or the LGPL are applicable instead
# of those above. If you wish to allow use of your version of this file only
# under the terms of either the GPL or the LGPL, and not to allow others to
# use your version of this file under the terms of the MPL, indicate your
# decision by deleting the provisions above and replace them with the notice
# and other provisions required by the GPL or the LGPL. If you do not delete
# the provisions above, a recipient may use your version of this file under
# the terms of any one of the MPL, the GPL or the LGPL.
#
# ***** END LICENSE BLOCK *****
package mozLock;
use strict;
use IO::File;
use Cwd;
BEGIN {
use Exporter ();
use vars qw ($VERSION @ISA @EXPORT @EXPORT_OK %EXPORT_TAGS);
$VERSION = 1.00;
@ISA = qw(Exporter);
@EXPORT = qw(&mozLock &mozUnlock);
%EXPORT_TAGS = ( );
@EXPORT_OK = qw();
}
my $lockcounter = 0;
my $locklimit = 100;
my $locksleep = 0.1;
my %lockhash;
# File::Spec->rel2abs appears to be broken in ActiveState Perl 5.22
# so roll our own
sub priv_abspath($) {
my ($file) = @_;
my ($dir, $out);
my (@inlist, @outlist);
# Force files to have unix paths.
$file =~ s/\\/\//g;
# Check if file is already absolute
if ($file =~ m/^\// || substr($file, 1, 1) eq ':') {
return $file;
}
$out = cwd . "/$file";
# Do what File::Spec->canonpath should do
@inlist = split(/\//, $out);
foreach $dir (@inlist) {
if ($dir eq '..') {
pop @outlist;
} else {
push @outlist, $dir;
}
}
$out = join '/',@outlist;
return $out;
}
sub mozLock($) {
my ($inlockfile) = @_;
my ($lockhandle, $lockfile);
$lockfile = priv_abspath($inlockfile);
#print "LOCK: $lockfile\n";
$lockcounter = 0;
$lockhandle = new IO::File || die "Could not create filehandle for $lockfile: $!\n";
while ($lockcounter < $locklimit) {
if (! -e $lockfile) {
open($lockhandle, ">$lockfile") || die "$lockfile: $!\n";
$lockhash{$lockfile} = $lockhandle;
last;
}
$lockcounter++;
select(undef,undef,undef, $locksleep);
}
if ($lockcounter >= $locklimit) {
undef $lockhandle;
die "$0: Could not get lockfile $lockfile.\nRemove $lockfile to clear up\n";
}
}
sub mozUnlock($) {
my ($inlockfile) = @_;
my ($lockhandle, $lockfile);
#$lockfile = File::Spec->rel2abs($inlockfile);
$lockfile = priv_abspath($inlockfile);
#print "UNLOCK: $lockfile\n";
$lockhandle = $lockhash{$lockfile};
if (defined($lockhandle)) {
close($lockhandle);
$lockhash{$lockfile} = undef;
unlink($lockfile);
} else {
print "WARNING: $0: lockhandle for $lockfile not defined. Lock may not be removed.\n";
}
}
END {};
1;