This flag was the only remaining one that was inverted as a blocking
condition, requiring special handling to preset it on sedesc allocation.
Let's flip it in its definition and accessors.
Function arguments and local variables called "cs" were renamed to "sc"
to avoid future confusion. Both the core functions and the ones in the
resolvers files were updated.
Function arguments and local variables called "cs" were renamed to "sc"
to avoid future confusion. The HTTP analyser and the backend functions
were all updated after being reviewed. Function stream_update_both_cs()
was renamed to stream_update_both_sc()
Function arguments and local variables called "cs" were renamed to "sc"
to avoid future confusion. The "nb_cs" stream-connector counter was
renamed to "nb_sc" and qc_attach_cs() was renamed to qc_attach_sc().
Function arguments and local variables called "cs" were renamed to "sc"
to avoid future confusion. The change is huge (~580 lines), so extreme
care was given not to change anything else.
The check struct had a "cs" field renamed to "sc", which also required
a tiny update to a few functions using it to distinguish a check from
a stream (log.c, payload.c, ssl_sample.c, tcp_sample.c, tcpcheck.c,
connection.c).
Function arguments and local variables called "cs" were renamed to "sc".
The presence of one "cs=" in the debugging traces was also turned to
"sc=" for consistency.
There's no more reason for keepin the code and definitions in conn_stream,
let's move all that to stconn. The alphabetical ordering of include files
was adjusted.
This file contains all the stream-connector functions that are specific
to application layers of type stream. So let's name it accordingly so
that it's easier to figure what's located there.
The alphabetical ordering of include files was preserved.
An equivalent applet_need_more_data() was added as well since that function
is mostly used from applet code. It makes it much clearer that the applet
is waiting for data from the stream layer.
These ones are essentially for the stream endpoint, let's give them a
name that matches the intent. Equivalent versions were provided in the
applet namespace to ease code legibility.
These ones were used exactly once and together, in sc_is_send_allowed().
No need to give them confusing names, instead let's just put the flags,
they're way more explicit, and drop the two functions.
This flag indicates the that stream endpoint is willing to consume output
data from the stream. Its new name makes this more explicit. The function
names will be updated accordingly, which will remove the disturbing "get"
everywhere.
The following flags are not at all related to the endpoint but to the
connector itself:
- SE_FL_RXBLK_ROOM
- SE_FL_RXBLK_BUFF
- SE_FL_RXBLK_CHAN
As such they have no business staying in the endpoint descriptor and
they must move to the stream connector. They've also been renamed
accordingly to better match what they correspond to (the same name
as the function that sets them).
The rare occurrences of cs_rx_blocked() were replaced by an explicit
test on the list of flags. The reason is that cs_rx_blocked() used to
preserve some tests that are not needed at certain places since already
known. For the same reason SE_FL_RXBLK_ANY wasn't converted. As such it
will later be possible to carefully review these few locations and
eliminate the unneeded flags from the tests. No particular function
was made to test them since they're explicit enough.
It now looks like ci_putchk() and friends could very well place the flag
themselves on the connector when they detect a buffer full condition, as
this would significantly simplify the high-level API. But all usages must
first be reviewed before this simplification can be done. For now it
remains done by applet_put*() instead.
It's more explicit this way. The cs_rx_endp_ready() function could be
removed so that the flag is directly tested. In the future it should
be inverted and the few places where it's set (or preserved via
SE_FL_APP_MASK) could be dropped.
At plenty of places we combine multiple flags checks to determine if we
can receive (endp_ready, rx_blocked, cf_shutr etc). Let's group them
under a single function that is meant to replace existing tests.
Some tests were only checking the rxblk flags at the connection level,
so for now they were not converted, this requires a bit of auditing
first, and probably a test to determine whether or not to check for
cf_shutr (e.g. there is none if no stream is present).
The analysis of cs_rx_endp_more() showed that the purpose is for a stream
endpoint to inform the connector that it's ready to deliver more data to
that one, and conversely cs_rx_endp_done() that it's done delivering data
so it should not be bothered again for this.
This was modified two ways:
- the operation is no longer performed on the connector but on the
endpoint so that there is no more doubt when reading applet code
about what this rx refers to; it's the endpoint that has more or
no more data.
- an applet implementation is also provided and mostly used from
applet code since it saves the caller from having to access the
endpoint descriptor.
It's visible that the flag ought to be inverted because some places
have to set it by default for no reason.
These functions are used by the application layer to disable or enable
reading at the stream connector's level when the input buffer failed to
be allocated (or was finally allocated). The new names makes things
clearer.
These functions were used by the channel to inform the lower layer
whether reading was acceptable or not. Usually this directly mimmicks
the CF_DONT_READ flag from the channel, which may be set when it's
desired not to buffer incoming data that will not be processed, or
that the buffer wants to be flushed before starting to read again,
or that bandwidth limiting might be enforced, etc. It's always a
policy reason, not a purely resource-based one.
The new name mor eclearly indicates that a stream connector cannot make
any more progress because it needs room in the channel buffer, or that
it may be unblocked because the buffer now has more room available. The
testing function is sc_waiting_room(). This is mostly used by applets.
Note that the flags will change soon.
This makes SE_FL_APPLET_NEED_CONN autonomous, in that we check for it
everywhere we have a relevant cs_rx_blocked(), so that the flag doesn't
need anymore to be covered by cs_rx_blocked(). Indeed, this flag doesn't
really translate a receive blocking condition but rather a refusal to
wake up an applet that is waiting for a connection to finish to setup.
This also ensures we will not risk to set it back on a new endpoint
after cs_reset_endp() via SE_FL_APP_MASK, because the flag being
specific to the endpoint only and not to the connector, we don't
want to preserve it when replacing the endpoint.
It's possible that cs_chk_rcv() could later be further simplified if
we can demonstrate that the two tests in it can be merged.
This flag is exclusively used when a front applet needs to wait for the
other side to connect (or fail to). Let's give it a more explicit name
and remove the ambiguous function that was used only once.
This also ensures we will not risk to set it back on a new endpoint
after cs_reset_endp() via SE_FL_APP_MASK, because the flag being
specific to the endpoint only and not to the connector, we don't
want to preserve it when replacing the endpoint.
This flag is no more needed, it was only set on shut read to be tested
by cs_rx_blocked() which is now properly tested for shutr as well. The
cs_rx_blk_shut() calls were removed. Interestingly it allowed to remove
a special case in the L7 retry code.
This also ensures we will not risk to set it back on a new endpoint
after cs_reset_endp() via SE_FL_APP_MASK.
One flag (RXBLK_SHUT) is always set with CF_SHUTR, so in order to remove
it, we first need to make sure we always check for CF_SHUTR where
cs_rx_blocked() is being used.
When a shutdown(WR) is performed, send is no longer allowed, and that is
currently handled by the explicit cs_done_get() in the various shutw()
calls. That's a bit ugly and complicated for no reason, let's simply
integrate the test of SHUTW in sc_is_send_allowed().
Note that the test could also be added wherever sc_is_send_allowed() is
used but for now proceeding like this limits the changes.
sc_is_send_allowed() is now used everywhere instead of the combination
of cs_tx_endp_ready() && !cs_tx_blocked(). There's no place where we
need them individually thus it's simpler. The test was placed in cs_util
as we'll complete it later.
A number of functions in cs_utils.h are not usable from functions taking
a const because they're not declared as using const, despite never
modifying the stconn. Let's address this for the following ones:
sc_ic(), sc_oc(), sc_ib(), sc_ob(), sc_strm_task(),
cs_opposite(), sc_conn_ready(), cs_src(), cs_dst(),
First it applies to the stream endpoint and not the conn_stream, and
second it only tests and touches the flags so it makes sense to call
it se_fl_ like other functions which only manipulate the flags, as
it's just a special case of flags.
It returns an stconn from a connection and not the opposite, so the name
change was more appropriate. In addition it was moved to connection.h
which manipulates the connection stuff, and it happens that only
connection.c uses it.
The following functions which act on a connection-based stream connector
were renamed to sc_conn_* (~60 places):
cs_conn_drain_and_shut
cs_conn_process
cs_conn_read0
cs_conn_ready
cs_conn_recv
cs_conn_send
cs_conn_shut
cs_conn_shutr
cs_conn_shutw
The function doesn't return a pointer to the mux but to the mux stream
(h1s, h2s etc). Let's adjust its name to reflect this. It's rarely used,
the name can be enlarged a bit. And of course s/cs/sc to accommodate for
the updated name.
These functions return the app-layer associated with an stconn, which
is a check, a stream or a stream's task. They're used a lot to access
channels, flags and for waking up tasks. Let's just name them
appropriately for the stream connector.
We're starting to propagate the stream connector's new name through the
API. Most call places of these functions that retrieve the channel or its
buffer are in applets. The local variable names are not changed in order
to keep the changes small and reviewable. There were ~92 uses of cs_ic(),
~96 of cs_oc() (due to co_get*() being less factorizable than ci_put*),
and ~5 accesses to the buffer itself.
