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Message-ID: <00ed01c0dfa0$db3e0490$bd431b09@sashimi>
From: "Bill Stoddard" <bill@wstoddard.com>
To: <new-httpd@apache.org>
References: <00d101c0df93$2dd76010$bd431b09@sashimi>
Subject: Re: Allowing modules to add input filters is broken
Date: Fri, 18 May 2001 09:45:52 -0400
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I am getting a bit more insite into this problem.  If you want to add input
filters, you need to do it with the pre_connection hook, not the
insert_filters hook. The insert_filters hook is really only useful for
output filters. This sould be a nice bit of info do document somewhere...

Bill

----- Original Message -----
From: "Bill Stoddard" <bill@wstoddard.com>
To: <new-httpd@apache.org>
Sent: Friday, May 18, 2001 8:07 AM
Subject: Allowing modules to add input filters is broken


> To the best of my knowledge, there is no way for a module to add input
> filters -- in time for them to be used during input processing --.   Sure
a
> module can call add_input_filter, but the ap_run_insert_filter hook is run
> too late for input filters to have any effect.
>
> There are several different ways to fix this....
>
> 1.  Call ap_run_insert_filter in time to be considered by the inbound
> processing.  (right after get_mime_headers() for instance). Using a
single,
> non parameterized function to add input and output filters to the stack
with
> the same call is trying to do too much with this one function. I cannot
> point to a speficic problem this will cause but I am sure they exist.
>
> 2. Pass an additional parameter on ap_run_insert_filter designating
whether
> modules should insert their input filters or output filters. Call
> ap_run_insert_filter(INSERT_INPUT_FILTERS) right after the call to
> get_mime_headers(). Call ap_run_insert_filter(INSERT_OUTPUT_FILTERS) where
> it is called today out of process_request_internal(). Modules would all
have
> to grok this parameter.
>
> 3. Another way to solve the this is to create a two new hooks to replace
the
> insert_filter hook:  ap_run_insert_input_filter() &
> ap_run_insert_output_filter() and call each hook at the appropriate point
in
> the cycle.
>
> 2 or 3 work for me. Leaning toward #3 right now.
>
> Ryan and Greg, opinions?
>
> Bill
>
>