Using this basic framework, you can return SUSPENDED from an HTTP Handler,
and then register a callback that is invoked by the MPM at a later time.
This initial version only supports _timers_ as callbacks, but in the future I
would like to add things like wait for socket activity, on a socket specified by
the handler.
Once in a callback, It is then the responsibility of the callback fucntion
to finish the HTTP Request handling, but this alows you to do cool things like
a fully async proxy, COMET support, or even rate limiting.
To prove I'm not insane, I've inlcuded an example module, mod_dialup.
You can configure it like this:
<Location "/docs">
ModemStandard "V.32"
</Location>
And for static files inside that path, you will be rate limited to V.32 speeds,
aka 9.6 kilobits/second.
Does anyone besides Rüdiger read commit emails :-) ?
I know there are likely huge problems with this, but I would like to see how far
we can push the Event MPM, figure out what to do better, if there is anything,
and then really dive into the 3.0 development before ApacheCon.
* server/mpm/experimental/event/fdqueue.h:
(timer_event_t): New structure to hold timer events and callback functions.
* server/mpm/experimental/event/fdqueue.c
(ap_queue_empty): Modify to also look at Timer Ring.
(ap_queue_init): Initialize Timer Ring.
(ap_queue_push_timer): New function, pushes a timer event into the queue.
(ap_queue_pop_something): Renamed function, returns a timer event or
a socket/pool for a worker thread to run.
* server/mpm/experimental/event/event.c
(process_socket): If the connection is in SUSPENDED state, don't force it
into linger mode yet, the callback will have to take care of that.
(push_timer2worker): New shortcut function, pushes timer event into queue
for a worker to run.
(timer_free_ring): New global data structure to recycle memory used by
timer events.
(timer_ring): New global data structure to hold active timer events.
(g_timer_ring_mtx): Thread mutex to protect timer event data structures.
(ap_mpm_register_timed_callback): New Function, registers a callback to be
invoked by the MPM at a later time.
(listener_thread): Calculate our wakeup time based on the upcoming Event
Queue, and after pollset_poll runs, push any Timers that have passed
onto worker threads to run.
(worker_thread): Call new queue pop method, and if the Timer Event is
non-null, invoke the callback. Once the callback is done, push the
structure onto the timer_free_ring, to be recycled.
(child_main): Initialize new mutex and ring structures.
* server/config.c
(ap_invoke_handler): Allow SUSPENDED aa valid return code from handlers.
* modules/http/http_core.c
(ap_process_http_async_connection): Don't close the connection when in
SUSPENDED state.
* modules/http/http_request.c
(ap_process_request_after_handler): New function, body pulled from the old,
ap_process_async_request. Split to let handlers invoke this so they
don't need to know all of the details of finishing a request.
(ap_process_async_request): If the handler returns SUSPENDED, don't do
anything but return.
* include/ap_mmn.h: Bump MMN.
* include/ap_mpm.h
(ap_mpm_register_timed_callback): New function.
* include/httpd.h:
(SUSPENDED): New return code for handlers.
(request_rec::invoke_mtx): New mutex to protect callback invokcations
from being run before the original handler finishes running.
(conn_state_e): Add a suspended state.
* include/http_request.h
(ap_process_request_after_handler): New function to make it easier for
handlers to finish the HTTP Request.
* modules/test/config.m4: Add mod_dialup to build.
* modules/test/mod_dialup.c: New rate limiting module, requires the Event MPM
to work.
git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@697357 13f79535-47bb-0310-9956-ffa450edef68
Ensure that the EOC bucket is inserted BEFORE an EOS bucket in bb as
some resource filters like mod_deflate pass everything up to the EOS
down the chain immediately and sent the remainder of the brigade later
(or even never). But in this case the ap_http_header_filter does not
get out of our way soon enough.
http_filters.c
Remove all data buckets that are in a brigade after an EOC bucket
was seen, as an EOC bucket tells us that no (further) resource
and protocol data should go out to the client. OTOH meta buckets
are still welcome as they might trigger needed actions down in
the chain (e.g. in network filters like SSL).
Remark 1: It is needed to dump ALL data buckets in the brigade
since an filter in between might have inserted data
buckets BEFORE the EOC bucket sent by the original
sender and we do NOT want this data to be sent.
Remark 2: Dumping all data buckets here does not necessarily mean
that no further data is send to the client as:
1. Network filters like SSL can still be triggered via
meta buckets to talk with the client e.g. for a
clean shutdown.
2. There could be still data that was buffered before
down in the chain that gets flushed by a FLUSH or an
EOS bucket.
PR: 37770
git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@660726 13f79535-47bb-0310-9956-ffa450edef68
Send the request line and trailing CRLF in ASCII.
Submitted by: David Jones <oscaremma gmail.com>
Reviewed and tested by: gregames
git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@659560 13f79535-47bb-0310-9956-ffa450edef68
ap_parse_request_body function out of the http module and into a
new module called mod_request, reducing the size of the core.
git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@647263 13f79535-47bb-0310-9956-ffa450edef68
we are a reverse proxy request shutdown the connection WITHOUT ANY response
to trigger a retry by the client if allowed (as for idempotent requests).
BUT currently we should not do this if the request is the first request on
a keepalive connection as browsers like seamonkey only display an empty page
in this case and do not do a retry.
Related to PR 37770
git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@645813 13f79535-47bb-0310-9956-ffa450edef68
that we get less than 20% of the NOT_IN_LIMIT rules correct.
<Limit > works in about 4 directive contexts and yet, we ignore
this fact for 100's of directives. Simply eliminate this
nonsense in anticipation of a 100% solution.
git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@645189 13f79535-47bb-0310-9956-ffa450edef68
chunk size lines or empty lines after a chunk are read incomplete. This can
lead to a corruption inside the dechunking algorithm.
This patch has an issue with larger chunk-extensions which need to get thrown
away since we ignore them anyway.
PR: 19954, 41056
Tested by: niq
git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@609394 13f79535-47bb-0310-9956-ffa450edef68
This has no security impact since the browser cannot be tricked
into sending arbitrary method strings.
(words from jorton)
git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@603346 13f79535-47bb-0310-9956-ffa450edef68
Determined to be not generally exploitable, but a flaw in any case.
PR: 44014
Submitted by: Victor Stinner <victor.stinner inl.fr>
git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@600645 13f79535-47bb-0310-9956-ffa450edef68
that the connection is not persistent if the MPM process handling
the request is already exiting when the response header is built.
git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@594839 13f79535-47bb-0310-9956-ffa450edef68
