--- deliantra/server/lib/cf.pm	2007/04/17 18:40:32	1.248
+++ deliantra/server/lib/cf.pm	2007/04/18 12:43:54	1.249
@@ -2331,6 +2331,45 @@
    BDB::db_put $DB, undef, "$_[0]/$_[1]", Compress::LZF::sfreeze_cr $_[2], 0, sub { };
 }
 
+=item cf::cache $id => ...
+
+Generic caching function that returns the value of the resource $id,
+caching and regenerating as required.
+
+This function can block.
+
+   source    => filename returning the data (must be a scalar)
+   expensive => true == try to cache harder
+   filter    => sub that processes the data into a scalar
+
+=cut
+
+sub cache {
+   my ($id, %arg) = @_;
+
+   aio_stat $arg{source}
+      and Carp::croak "$arg{source}: $!";
+
+   my $meta = join ":", (stat _)[7,9];
+   my $md5;
+
+   if ($arg{expensive}) {
+      0 <= aio_load $arg{source}, my $buf
+         or Carp::croak "$arg{source}: $!";
+
+      $md5 = Digest::MD5::md5_hex $buf;
+   }
+
+   my $dbmeta = db_get "$id/meta";
+   if ($dbmeta ne $meta) {
+      # changed, we need to process
+   } else {
+      # just fetch
+   }
+
+
+}
+
 #############################################################################
 # the server's init and main functions
 
@@ -2802,6 +2841,9 @@
    );
 }
 
+# load additional modules
+use cf::pod;
+
 END { cf::emergency_save }
 
 1