Graeme Fowler <graeme@???> (Fr 11 Jun 2010 10:42:26 CEST): > On Fri, 2010-06-11 at 09:49 +0200, Jakob Hirsch wrote:
> > Hm, do you really need the _whole_ body? Otherwise,
> > ${sha1:$message_body} would do what you want (hash the first 500 bytes).
> > Otherwise I guess you could set message_body_visible to a high enough
> > number (like message_size_limit), but I'm not sure how efficient Exim is
> > handling such big strings. OTOH, it probably doesn't matter much on
> > todays machines, as long as you are not hitting some internal limits
> > (which I don't know of). If you care about efficiency, you could use dlfunc.
> > Or is this something useful for other Exim users, too?
>
> I would caution against a builtin which is this computationally
> intensive, especially in the case of large/very large messages. It will
> adversely affect Exim's processor utilisation (by some margin for very
> large messages) and greatly increase processing time.
>
> As Jakob says, the tools already exist to do this; better to make use of
> them (and perhaps generate a Wiki entry to explain how to do it, and
> why) than make Exim generate a hash for every message.
Probable we only need to compute the hash if we see a reference to this
variable in the current config file. Is there any chance (inside the
code writing the message to the spool) to "peek" if there is some
reference to $message_size_body_hash?
