Doing so ensures we don't need to use the stream anymore to prepare the
log information to report a failed handshake on an embryonic session.
Thus, prepare_mini_sess_log_prefix() now takes a session in argument.
Now that we have sess->origin to carry that information along, we don't
need to put that into strm->target anymore, so we remove one dependence
on the stream in embryonic connections.
Many such function need a session, and till now they used to dereference
the stream. Once we remove the stream from the embryonic session, this
will not be possible anymore.
So as of now, sample fetch functions will be called with this :
- sess = NULL, strm = NULL : never
- sess = valid, strm = NULL : tcp-req connection
- sess = valid, strm = valid, strm->txn = NULL : tcp-req content
- sess = valid, strm = valid, strm->txn = valid : http-req / http-res
All of them can now retrieve the HTTP transaction *if it exists* from
the stream and be sure to get NULL there when called with an embryonic
session.
The patch is a bit large because many locations were touched (all fetch
functions had to have their prototype adjusted). The opportunity was
taken to also uniformize the call names (the stream is now always "strm"
instead of "l4") and to fix indent where it was broken. This way when
we later introduce the session here there will be less confusion.
Now this one is dynamically allocated. It means that 280 bytes of memory
are saved per TCP stream, but more importantly that it will become
possible to remove the l7 pointer from fetches and converters since
it will be deduced from the stream and will support being null.
A lot of care was taken because it's easy to forget a test somewhere,
and the previous code used to always trust s->txn for being valid, but
all places seem to have been visited.
All HTTP fetch functions check the txn first so we shouldn't have any
issue there even when called from TCP. When branching from a TCP frontend
to an HTTP backend, the txn is properly allocated at the same time as the
hdr_idx.
This one will not necessarily be allocated for each stream, and we want
to use the fact that it equals null to know it's not present so that we
can always deduce its presence from the stream pointer.
This commit only creates the new pool.
The header captures are now general purpose captures since tcp rules
can use them to capture various contents. That removes a dependency
on http_txn that appeared in some sample fetch functions and in the
order by which captures and http_txn were allocated.
Interestingly the reset of the header captures were done at too many
places as http_init_txn() used to do it while it was done previously
in every call place.
When s->si[0].end was dereferenced as a connection or anything in
order to retrieve information about the originating session, we'll
now use sess->origin instead so that when we have to chain multiple
streams in HTTP/2, we'll keep accessing the same origin.
Just like for the listener, the frontend is session-wide so let's move
it to the session. There are a lot of places which were changed but the
changes are minimal in fact.
There is now a pointer to the session in the stream, which is NULL
for now. The session pool is created as well. Some parts will move
from the stream to the session now.
With HTTP/2, we'll have to support multiplexed streams. A stream is in
fact the largest part of what we currently call a session, it has buffers,
logs, etc.
In order to catch any error, this commit removes any reference to the
struct session and tries to rename most "session" occurrences in function
names to "stream" and "sess" to "strm" when that's related to a session.
The files stream.{c,h} were added and session.{c,h} removed.
The session will be reintroduced later and a few parts of the stream
will progressively be moved overthere. It will more or less contain
only what we need in an embryonic session.
Sample fetch functions and converters will have to change a bit so
that they'll use an L5 (session) instead of what's currently called
"L4" which is in fact L6 for now.
Once all changes are completed, we should see approximately this :
L7 - http_txn
L6 - stream
L5 - session
L4 - connection | applet
There will be at most one http_txn per stream, and a same session will
possibly be referenced by multiple streams. A connection will point to
a session and to a stream. The session will hold all the information
we need to keep even when we don't yet have a stream.
Some more cleanup is needed because some code was already far from
being clean. The server queue management still refers to sessions at
many places while comments talk about connections. This will have to
be cleaned up once we have a server-side connection pool manager.
Stream flags "SN_*" still need to be renamed, it doesn't seem like
any of them will need to move to the session.
