lib/WAIT/Index.pm

#                              -*- Mode: Cperl -*- 
# Index.pm -- 
# ITIID           : $ITI$ $Header $__Header$
# Author          : Ulrich Pfeifer
# Created On      : Thu Aug  8 13:05:10 1996
# Last Modified By: Ulrich Pfeifer
# Last Modified On: Sat Apr 27 18:06:47 2002
# Language        : CPerl
# Update Count    : 128
# Status          : Unknown, Use with caution!
# 
# Copyright (c) 1996-1997, Ulrich Pfeifer
# 

package WAIT::Index;
use WAIT::IndexScan;
use strict;
use BerkeleyDB;
use Fcntl;
use vars qw($VERSION);

$VERSION = "1.801"; # Table.pm tests if we are loaded by checking $VERSION

sub new {
  my $type = shift;
  my %parm = @_;
  my $self = {};

  unless ($self->{file} = $parm{file}) {
    require Carp;
    Carp::croak("No file specified");
  }
  unless ($self->{name} = $parm{name}) {
    require Carp;
    Carp::croak("No name specified");
  }
  unless ($self->{attr} = $parm{attr}) {
    require Carp;
    Carp::croak("No attributes specified");
  }
  bless $self, ref($type) || $type;
}

sub drop {
  my $self = shift;
  if ((caller)[0] eq 'WAIT::Table') { # Table knows about this
    my $file = $self->{file};
    ! (!-e $file or unlink $file);
  } else {                            # notify our database
    require Carp;
    Carp::croak(ref($self)."::drop called directly");
  }
}

sub open {
  my $self = shift;
  my $file = $self->{file};

  if ($self->{dbh}) {
    $self->{dbh};
  } else {
    my $dbmode = ($self->{mode} & O_CREAT) ? DB_CREATE : 0;
    $self->{dbh} = tie(%{$self->{db}}, 'BerkeleyDB::Btree',
                       -Filename => $self->{file},
                       -Subname  => 'records',
                       -Flags    => $dbmode,
                       -Mode     => 0664);
  }
}

sub insert {
  my $self  = shift;
  my $key   = shift;
  my %parm  = @_;

  defined $self->{db} or $self->open;

  my $tuple = join($;, map($parm{$_}, @{$self->{attr}}));

  if (exists $self->{db}->{$tuple}) {
    # duplicate entry
    return undef;
  }
  print STDERR "$tuple => $key\n";
  $self->{db}->{$tuple} = $key;
}

sub have {
  my $self  = shift;
  my %parm  = @_;

  defined $self->{db} or $self->open;

  my $tuple = join($;, map($parm{$_}, @{$self->{attr}}));

  print STDERR "$tuple <= ", $self->{db}->{$tuple}, "\n";
  $self->{db}->{$tuple};
}

sub fetch {
  my $self  = shift;
  my %parm  = @_;
  my @keys  = @{$self->{attr}->[0]};

  defined $self->{db} or $self->open;

  my $key   = join($;, map($parm{$_}, @keys));
  $self->{db}->{$key};
}

sub delete {
  my $self  = shift;
  my $key   = shift;
  my %parm  = @_;

  defined $self->{db} or $self->open;

  my $tuple = join($;, map($parm{$_}||"", @{$self->{attr}}));

  delete $self->{db}->{$tuple};
}

sub sync {
  my $self = shift;
  $self->{dbh}->db_sync if $self->{dbh};
}

sub close {
  my $self = shift;

  delete $self->{scans} if defined $self->{scans};

  if ($self->{dbh}) {
    delete $self->{dbh};
    delete $self->{db};
    #untie %{$self->{db}};
  }
}

#sub DESTROY { $_[0]->close }

sub open_scan {
  my $self = shift;
  my $code = shift;

  $self->{dbh} or $self->open;
  new WAIT::IndexScan $self, $code;
}

1;
1	# -- Mode: Cperl --
2	# Index.pm --
3	# ITIID : $ITI$ $Header $__Header$
4	# Author : Ulrich Pfeifer
5	# Created On : Thu Aug 8 13:05:10 1996
6	# Last Modified By: Ulrich Pfeifer
7	# Last Modified On: Sat Apr 27 18:06:47 2002
8	# Language : CPerl
9	# Update Count : 128
10	# Status : Unknown, Use with caution!
11	#
12	# Copyright (c) 1996-1997, Ulrich Pfeifer
13	#
14
15	package WAIT::Index;
16	use WAIT::IndexScan;
17	use strict;
18	use BerkeleyDB;
19	use Fcntl;
20	use vars qw($VERSION);
21
22	$VERSION = "1.801"; # Table.pm tests if we are loaded by checking $VERSION
23
24	sub new {
25	my $type = shift;
26	my %parm = @_;
27	my $self = {};
28
29	unless ($self->{file} = $parm{file}) {
30	require Carp;
31	Carp::croak("No file specified");
32	}
33	unless ($self->{name} = $parm{name}) {
34	require Carp;
35	Carp::croak("No name specified");
36	}
37	unless ($self->{attr} = $parm{attr}) {
38	require Carp;
39	Carp::croak("No attributes specified");
40	}
41	bless $self, ref($type) \|\| $type;
42	}
43
44	sub drop {
45	my $self = shift;
46	if ((caller)[0] eq 'WAIT::Table') { # Table knows about this
47	my $file = $self->{file};
48	! (!-e $file or unlink $file);
49	} else { # notify our database
50	require Carp;
51	Carp::croak(ref($self)."::drop called directly");
52	}
53	}
54
55	sub open {
56	my $self = shift;
57	my $file = $self->{file};
58
59	if ($self->{dbh}) {
60	$self->{dbh};
61	} else {
62	my $dbmode = ($self->{mode} & O_CREAT) ? DB_CREATE : 0;
63	$self->{dbh} = tie(%{$self->{db}}, 'BerkeleyDB::Btree',
64	-Filename => $self->{file},
65	-Subname => 'records',
66	-Flags => $dbmode,
67	-Mode => 0664);
68	}
69	}
70
71	sub insert {
72	my $self = shift;
73	my $key = shift;
74	my %parm = @_;
75
76	defined $self->{db} or $self->open;
77
78	my $tuple = join($;, map($parm{$_}, @{$self->{attr}}));
79
80	if (exists $self->{db}->{$tuple}) {
81	# duplicate entry
82	return undef;
83	}
84	print STDERR "$tuple => $key\n";
85	$self->{db}->{$tuple} = $key;
86	}
87
88	sub have {
89	my $self = shift;
90	my %parm = @_;
91
92	defined $self->{db} or $self->open;
93
94	my $tuple = join($;, map($parm{$_}, @{$self->{attr}}));
95
96	print STDERR "$tuple <= ", $self->{db}->{$tuple}, "\n";
97	$self->{db}->{$tuple};
98	}
99
100	sub fetch {
101	my $self = shift;
102	my %parm = @_;
103	my @keys = @{$self->{attr}->[0]};
104
105	defined $self->{db} or $self->open;
106
107	my $key = join($;, map($parm{$_}, @keys));
108	$self->{db}->{$key};
109	}
110
111	sub delete {
112	my $self = shift;
113	my $key = shift;
114	my %parm = @_;
115
116	defined $self->{db} or $self->open;
117
118	my $tuple = join($;, map($parm{$_}\|\|"", @{$self->{attr}}));
119
120	delete $self->{db}->{$tuple};
121	}
122
123	sub sync {
124	my $self = shift;
125	$self->{dbh}->db_sync if $self->{dbh};
126	}
127
128	sub close {
129	my $self = shift;
130
131	delete $self->{scans} if defined $self->{scans};
132
133	if ($self->{dbh}) {
134	delete $self->{dbh};
135	delete $self->{db};
136	#untie %{$self->{db}};
137	}
138	}
139
140	#sub DESTROY { $_[0]->close }
141
142	sub open_scan {
143	my $self = shift;
144	my $code = shift;
145
146	$self->{dbh} or $self->open;
147	new WAIT::IndexScan $self, $code;
148	}
149
150	1;