Re: Counting headers?

Excerpts from mail: (10-Mar-98) Counting headers? by Andrew 
> What I'd like to do is come up with a recipe that'll detect these.
> I.e. count the number of received headers and if there's only one,
> dump it. If there's more than one, check to see which ones are just
> passing through my local mail servers, and if none remain after
> eliminating those, dump it.
This sounds like a bad idea to me. (What about e-mail received from local
users?) But it sounded like fun to code, so here is one possible solution:

This is really just an alteration to a recipe I wrote and posted last year.
(See 
<http://www.rosat.mpe-garching.mpg.de/mailing-lists/procmail/1997-09/msg00436.html>
 for details.)

This could probably be implemented using a non-recursive algorithm, but since
I already had the aforementioned receipe on hand, I chose to do it this way.

In your .procmailrc, put the following:
#--------------------------------------------------------------------------
RECEIVEDHDR = "(Received:[      ]*)"
# Change the mail host addresses in the next line to match your local servers.
LOCALRECEIVEDHDR = "(Received:.* by ((mail|mx1|mx2)\.your-domain\.com))"

:0
* $ ^\/$RECEIVEDHDR(.*$)+
{
     HEADERLINES = $MATCH
     COUNT_RECEIVED = 0
     COUNT_NONLOCAL_RECEIVED = 0

     INCLUDERC = count-received.rc

     :0:
     * COUNT_RECEIVED ?? ^^1^^
     mbox.possible-spam
     # or /dev/null or whatever you want to do with it...

     :0:
     * COUNT_NONLOCAL_RECEIVED ?? ^^0^^
     mbox.possible-spam
     # or /dev/null or whatever you want to do with it...
}
#--------------------------------------------------------------------------

Then, make a file named count-received.rc with the following recipe in it:

#--------------------------------------------------------------------------
:0
* HEADERLINES ?? $ ^^(.*$)+\/$RECEIVEDHDR(.*$)+
{ REMAININGLINES = $MATCH }

:0E
{ REMAININGLINES }

:0
* HEADERLINES ?? $ ^^$RECEIVEDHDR
{
     # Increment COUNT_RECEIVED by 1.
     :0
     * $ $COUNT_RECEIVED^0
     * 1^0
     { COUNT_RECEIVED = $= }

     :0
     * HEADERLINES ?? $ ! ^^$LOCALRECEIVEDHDR
     {
          # Increment COUNT_NONLOCAL_RECEIVED by 1.
          :0
          * $ $COUNT_NONLOCAL_RECEIVED^0
          * 1^0
          { COUNT_NONLOCAL_RECEIVED = $= }
     }
}

# Now, do recursion, but only if REMAININGLINES is not an empty string.
:0
* REMAININGLINES ?? .
{
     HEADERLINES = $REMAININGLINES

     INCLUDERC = $_

}
#--------------------------------------------------------------------------

Note: The above code has been tested.

Later,
Ed