internal redirect/subreq changes break custom headers (and dir index scripts?)

[Greg Stein <gs...@lyra.org>]

During my work just now on the method number changes, I found that the
Allow: header was not being returned by the OPTIONS request. Tracing the
code showed that it *was* inserting the proper header into r->headers_out.
However, it was doing that for a redirect, and the headers never made it out
the pipe.

[ I updated back to an hour before my commit and tried that: still no Allow:
  header, so it wasn't my changes... ]

This is happening for the Allow: header in an OPTIONS request, but I believe
it will also happen for any response that doesn't have a body. I think this
is what is happening:

* I did an OPTIONS for "/"

* mod_negotiation did an internal redirect to /index.html.en

* the Allow: header was added to r->headers_out

* the request was finalized by ap_internal_redirect()

* the normal operation of ap_finalize_request_protocol() is to send an EOS
  bucket. this prods HEADER_OUT to send the headers.

* however, since the internal redirect is a subrequest, it gets an "EOS
  chomper" filter on it. the EOS is never delivered, and the headers are
  never sent.

* somewhere in the unwinding process, the main request is finalized, and it
  gets an EOS which flushes the *main* request headers. which are, of
  course, quite wrong.


Hmm. I just tried to do some testing with an "index.cgi" file. I added
index.cgi to the DirectoryIndex directive, and then did the AddHandler for
.cgi -> cgi-script. It would not run the index.cgi script(!). Maybe I
misconfigured, but that is definitely a big-time regression in
functionality.

Not sure where *that* one fails.


I know that index.cgi type stuff also requires an internal redirect, but I'm
out of time to dig into that one, too.

Cheers,
-g

-- 
Greg Stein, http://www.lyra.org/