[Email-SIG] header folding

[R. David Murray]

On Wed, 27 Jul 2011 23:07:33 +0900, "Stephen J. Turnbull" <stephen at xemacs.org> wrote:
> R. David Murray writes:
> 
>  > That's an interesting point.  So perhaps I should rename the control
>  > 'header_source_refold'.
> 
> I don't know have a strong opinion, but I tend to think it's
> unnecessary.
> 
>  > On the other hand, we could also provide a separate control
>  > for whether or not quoted printable bodies in particular were
>  > folded,
> 
> If the body is already known to be quoted-printable, you don't really
> have a choice.  Folding lines longer than 76 characters after
> quoted-printable encoding is required by RFC 2045.  Of course you can

Right, I realized what I said didn't make sense after I hit send :)

> do more folding than necessary (eg, fold an 85-character line at 35
> and 70 characters), but that doesn't seem very useful to me.

Well, the use case I was thinking of was fixing up non-conformant output
from another MUA (quoted printable but with overlong lines).  I don't
know if such exists in the wild, but I would expect that it does,
everything else seems to :)  Still it may be a YAGNI, since any such
are most likely to be spammers.

> It seems to me that the policy question (if it exists) is "We have an
> all-ASCII body with 'long lines'.  Shall we encode in quoted-printable
> only for the purpose of folding the long lines?"

Yes, that would be a similar case:  we have a body that doesn't conform
to the "SHOULD" limit of 78; if refold_source is 'long', should we
use QP to fold it?  But this question also arises if the application
is attaching a text part with lines longer than 78 characters.  As you
suggested it might be the case that we don't want to QP encode such text.
That question, QP encoding only to fold text parts with long lines, thus
seems to be a separate policy control (and I do think we want one for it).
So if we have 'refold_source' set to 'long', an unencoded text part with
long lines would get QP encoded if and only if this new policy setting
that we haven't named yet is set to fold such parts using QP.

--
R. David Murray           http://www.bitdance.com