mdw@git.distorted.org.uk Git - catacomb-perl/blob - Catacomb/Cache.pm

   1 # -*-perl-*-
   2 #
   3 # $Id$
   4 #
   5 # Caching for fields, curves, groups, ...
   6 #
   7 # (c) 2004 Straylight/Edgeware
   8 #
   9
  10 #----- Licensing notice -----------------------------------------------------
  11 #
  12 # This file is part of the Perl interface to Catacomb.
  13 #
  14 # Catacomb/Perl is free software; you can redistribute it and/or modify
  15 # it under the terms of the GNU General Public License as published by
  16 # the Free Software Foundation; either version 2 of the License, or
  17 # (at your option) any later version.
  18 #
  19 # Catacomb/Perl is distributed in the hope that it will be useful,
  20 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  21 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22 # GNU General Public License for more details.
  23 #
  24 # You should have received a copy of the GNU General Public License
  25 # along with Catacomb/Perl; if not, write to the Free Software Foundation,
  26 # Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  27
  28 package Catacomb::Cache::Ref;
  29
  30 sub new {
  31   my ($me, $c) = @_;
  32   $c->[0]++;
  33   return bless [$c], $me;
  34 }
  35
  36 sub DESTROY {
  37   my ($me) = @_;
  38   my $c = $me->[0];
  39   if ($c->[0] > 1) { $c->[0]--; return; }
  40   delete $c->[1]{$c->[2]};
  41 }
  42
  43 package Catacomb::Cache;
  44
  45 $debug = 1;
  46
  47 sub stringify {
  48   my ($x) = @_;
  49   if (ref($x) eq ARRAY) {
  50     return "[" . join("/", map(stringify($_), @$x)) . "]";
  51   } else {
  52     return $x;
  53   }
  54 }
  55
  56 sub new { my ($me) = @_; return bless { }, $me; }
  57
  58 sub intern {
  59   my ($c, $x) = @_;
  60   my $k = stringify($x->get());
  61   my $e;
  62   if (exists($c->{$k})) {
  63     $e = $c->{$k};
  64   } else {
  65     $e = $c->{$k} = [0, $c, $k, $x];
  66   }
  67   return $e->[3], Catacomb::Cache::Ref->new($e);
  68 }
  69
  70 #----- That's all, folks ----------------------------------------------------
  71
  72 1;