1 files changed, 48 insertions, 0 deletions
diff --git a/lib/Memoize/ExpireFile.pm b/lib/Memoize/ExpireFile.pm
new file mode 100644
index 0000000000..958b807cfa
--- /dev/null
+++ b/lib/Memoize/ExpireFile.pm
@@ -0,0 +1,48 @@
+
+package Memoize::ExpireFile;
+use Carp;
+
+sub TIEHASH {
+  my ($package, %args) = @_;
+  my %cache;
+  if ($args{TIE}) {
+    my ($module, @opts) = @{$args{TIE}};
+    my $modulefile = $module . '.pm';
+    $modulefile =~ s{::}{/}g;
+    eval { require $modulefile };
+    if ($@) {
+      croak "Memoize::ExpireFile: Couldn't load hash tie module `$module': $@; aborting";
+    }
+    my $rc = (tie %cache => $module, @opts);
+    unless ($rc) {
+      croak "Memoize::ExpireFile: Couldn't tie hash to `$module': $@; aborting";
+    }
+  }
+  bless {ARGS => \%args, C => \%cache} => $package;
+}
+
+
+sub STORE {
+  my ($self, $key, $data) = @_;
+  my $cache = $self->{C};
+  my $cur_date = pack("N", (stat($key))[9]);
+  $cache->{"C$key"} = $data;
+  $cache->{"T$key"} = $cur_date;
+}
+
+sub FETCH {
+  my ($self, $key) = @_;
+  $self->{C}{"C$key"};
+}
+
+sub EXISTS {
+  my ($self, $key) = @_;
+  my $old_date = $self->{C}{"T$key"} || "0";
+  my $cur_date = pack("N", (stat($key))[9]);
+  if ($self->{ARGS}{CHECK_DATE} && $old_date gt $cur_date) {
+    return $self->{ARGS}{CHECK_DATE}->($key, $old_date, $cur_date);
+  } 
+  return $old_date ge $cur_date;
+}
+
+1;