[fetchmail-devel] Re: RFC: Patch to fix Berlios Bug #5849

[Sunil S. <sh...@bo...>]

Quoting from Matthias Andree's mail on Tue, Dec 13, 2005:
> Well, one thing that astonished me a bit is that on one hand the input
> side is clearly encapsulated with object-oriented practices, while the
> output side (SMTP/LMTP; MDA; BSMTP) is not nearly as clearly separated.
> On the other hand, we use POP3 sibling "protocols" where a distinction
> per "authentication" would be sufficient.

...

> Sending bounce messages is a sore spot. AFAIR, no bounce messages are
> ever sent if bogofilter is in MDA mode. MDA mode doesn't work for
> multidrop, as you'll probably recall from past discussions over at
> fetchmail-friends. I don't know about BSMTP restrictions.

I had worked on splitting up sink.c. I gave up when there were too
many local changes and not even read access to the repository then.
Also, by the time I had almost finished, a new version of fetchmail
had come out which had too many changes in sink.c.

One thing that had stumped me then was the FALLBACK_MDA feature. After
splitting, implementing FALLBACK_MDA would be difficult (but not
impossible). Should this feature be continued to be supported?

Once splitting is completed, making MDA work in multidrop should not
be a problem.

Here would be the aim of this development:

- Split sink.c into sink-smtp.c, sink-bsmtp.c, sink-mda.c (and
  possibly, sink-lmtp.c).
- Make a structure (similar to struct method) to handle the sending of
  messages.
- Make the mda code handle the exit code in accordance with
  <sysexits.h>.
- Make the mda code work in multidrop mode.
- Make the parser accept options per sink.
- Make all sink options (like esmtpname) per sink.
- Make FALLBACK_MDA work.

Potential issues involved:
- Cross platform:
  * Does <sysexits.h> exists on all platforms?
  * Do all platforms have at least EX_OK, EX__BASE, EX__MAX?
  * Do all platforms have the common exit codes that need to be
    handled specially (like EX_NOUSER)?
- How to specify options per smtphost?
- Any other issues?

Any comments on this?

-- 
Sunil Shetye.