DB/Lock/NoLock.pm


=head1 NAME

SuikaWiki::DB::Lock::NoLock - SuikaWiki: "No lock" Locking Implementation

=head1 DESCRIPTION

C<SuikaWiki::DB::Lock::NoLock> implements locking interface that
actually make nothing done.  This module can be used in context where
SuikaWiki WikiDB interface requires some lock module implementation
but locking is not necessary (or not preferred).

This module is part of SuikaWiki.

=cut

package SuikaWiki::DB::Lock::NoLock;
use strict;
our $VERSION=do{my @r=(q$Revision: 1.2 $=~/\d+/g);sprintf "%d."."%02d" x $#r,@r};

=head1 METHODS

=over 4

=item $locker = SuikaWiki::DB::Lock::NoLock->new (%options)

Generates a new instance of this module.

Options:

=over 4

=item appendable => 1/0 (Default 1)

=item readable => 1/0 (Default 1)

=item writable => 1/0 (Default 0)

=back

=cut

sub new ($%) {
  my $self = bless {}, shift;
  my %opt = @_;
  $self->{option}->{readable} = defined $opt{readable} ? $opt{readable} : 1;
  $self->{option}->{writable} = defined $opt{writable} ? $opt{writable} : 0;
  $self->{option}->{appendable} = defined $opt{appendable} ? $opt{appendable} : 1;
  $self;
}

=item 1/0 = $locker->lock ()

Lock.  Returns C<1> if lock is successed.  Otherwise C<0> is returned.

=cut

sub lock ($) {
  my $self = shift;
  $self->{locked} ? 1 : "0 but true";
}

=item 1/0 = $locker->unlock ()

Unlock.  Returns C<1> if unlock is success.  C<-1> if lock file is
lost.  Otherwise C<0> is returned.

=cut

sub unlock ($) {
  my $self = shift;
  $self->{locked} ? 1 : "0 but true";
}

=item 1/0 = $locker->readable ()

Returns whether readable or not.

=item 1/0 = $locker->writable ()

Returns whether writable or not.

=item 1/0 = $locker->appendable

Returns whether line-appendable or not.

=item 1/0 = $locker->locked ()

Returns whether locked or not.       

=cut

sub readable ($) { shift->{option}->{readable} }
sub writable ($) { shift->{option}->{writable} }
sub appendable ($) { shift->{option}->{appendable} }

sub locked ($) { "0 but true" }

=head1 EXAMPLE

    require SuikaWiki::DB::Lock::NoLock;
    my $locker = SuikaWiki::DB::Lock::NoLock->new;
    
    $locker->lock or die "Can't lock";
    
    open DATA, 'foo.txt';
    while (<DATA>) {
      # something
    }
    close DATA;
    
    open NEWDATA, '>', 'bar.txt';
      # something
    close NEWDATA;
    
    $locker->unlock or die "Can't unlock";

=head1 SEE ALSO

SuikaWiki:"SuikaWiki//WikiDB" 
<http://suika.fam.cx/~wakaba/-temp/wiki/wiki?SuikaWiki%2F%2FWikiDB>,
L<SuikaWiki::DB::Util::Lock>

=head1 LICENSE

Copyright 2003-2004 Wakaba <w@suika.fam.cx>.  All rights reserved.

This program is free software; you can redistribute it and/or
modify it under the same terms as Perl itself.

=cut

1; # $Date: 2004/04/02 04:32:48 $
1	wakaba	1.1
2			=head1 NAME
3
4			SuikaWiki::DB::Lock::NoLock - SuikaWiki: "No lock" Locking Implementation
5
6			=head1 DESCRIPTION
7
8			C<SuikaWiki::DB::Lock::NoLock> implements locking interface that
9			actually make nothing done. This module can be used in context where
10			SuikaWiki WikiDB interface requires some lock module implementation
11			but locking is not necessary (or not preferred).
12
13			This module is part of SuikaWiki.
14
15			=cut
16
17			package SuikaWiki::DB::Lock::NoLock;
18			use strict;
19	wakaba	1.3	our $VERSION=do{my @r=(q$Revision: 1.2 $=~/\d+/g);sprintf "%d."."%02d" x $#r,@r};
20	wakaba	1.1
21			=head1 METHODS
22
23			=over 4
24
25			=item $locker = SuikaWiki::DB::Lock::NoLock->new (%options)
26
27			Generates a new instance of this module.
28	wakaba	1.3
29			Options:
30
31			=over 4
32
33			=item appendable => 1/0 (Default 1)
34
35			=item readable => 1/0 (Default 1)
36
37			=item writable => 1/0 (Default 0)
38
39			=back
40	wakaba	1.1
41			=cut
42
43			sub new ($%) {
44	wakaba	1.3	my $self = bless {}, shift;
45			my %opt = @_;
46			$self->{option}->{readable} = defined $opt{readable} ? $opt{readable} : 1;
47			$self->{option}->{writable} = defined $opt{writable} ? $opt{writable} : 0;
48			$self->{option}->{appendable} = defined $opt{appendable} ? $opt{appendable} : 1;
49			$self;
50	wakaba	1.1	}
51
52			=item 1/0 = $locker->lock ()
53
54			Lock. Returns C<1> if lock is successed. Otherwise C<0> is returned.
55
56			=cut
57
58			sub lock ($) {
59			my $self = shift;
60			$self->{locked} ? 1 : "0 but true";
61			}
62
63			=item 1/0 = $locker->unlock ()
64
65			Unlock. Returns C<1> if unlock is success. C<-1> if lock file is
66			lost. Otherwise C<0> is returned.
67
68			=cut
69
70			sub unlock ($) {
71			my $self = shift;
72			$self->{locked} ? 1 : "0 but true";
73			}
74
75			=item 1/0 = $locker->readable ()
76
77	wakaba	1.2	Returns whether readable or not.
78	wakaba	1.1
79			=item 1/0 = $locker->writable ()
80
81	wakaba	1.2	Returns whether writable or not.
82
83			=item 1/0 = $locker->appendable
84
85			Returns whether line-appendable or not.
86	wakaba	1.1
87			=item 1/0 = $locker->locked ()
88
89			Returns whether locked or not.
90
91			=cut
92
93	wakaba	1.3	sub readable ($) { shift->{option}->{readable} }
94			sub writable ($) { shift->{option}->{writable} }
95			sub appendable ($) { shift->{option}->{appendable} }
96	wakaba	1.1
97			sub locked ($) { "0 but true" }
98
99			=head1 EXAMPLE
100
101			require SuikaWiki::DB::Lock::NoLock;
102			my $locker = SuikaWiki::DB::Lock::NoLock->new;
103
104			$locker->lock or die "Can't lock";
105
106			open DATA, 'foo.txt';
107			while (<DATA>) {
108			# something
109			}
110			close DATA;
111
112			open NEWDATA, '>', 'bar.txt';
113			# something
114			close NEWDATA;
115
116			$locker->unlock or die "Can't unlock";
117
118			=head1 SEE ALSO
119
120			SuikaWiki:"SuikaWiki//WikiDB"
121			<http://suika.fam.cx/~wakaba/-temp/wiki/wiki?SuikaWiki%2F%2FWikiDB>,
122			L<SuikaWiki::DB::Util::Lock>
123
124			=head1 LICENSE
125
126			Copyright 2003-2004 Wakaba <w@suika.fam.cx>. All rights reserved.
127
128			This program is free software; you can redistribute it and/or
129			modify it under the same terms as Perl itself.
130
131			=cut
132
133	wakaba	1.3	1; # $Date: 2004/04/02 04:32:48 $