This will instantly stop all listeners except those which belong to
a proxy configured with a grace time. This means that UDP listeners,
and peers will also be stopped when called this way.
Since the listeners were split into receiver+listener, this field ought
to have been renamed because it's confusing. It really links receivers
and not listeners, as most of the time it's used via rx.proto_list!
The nb_listeners field was updated accordingly.
protocol_enable_all() calls proto->enable_all() for all protocols,
which is always equal to enable_all_listeners() which in turn simply is
a generic loop calling enable_listener() always returning ERR_NONE. Let's
clean this madness by first calling enable_listener() directly from
protocol_enable_all().
These two functions are used to pause and resume all listeners of
all protocols. They use the standard listener functions for this
so they're supposed to handle the situation gracefully regardless
of the upper proxies' states, and they will report completion on
proxies once the switch is performed.
It might be nice to define a particular "failed" state for listeners
that cannot resume and to count them on proxies in order to mention
that they're definitely stuck. On the other hand, the current
situation is retryable which is quite appreciable as well.
The protocol array used to be only indexed by socket family, which is very
problematic with UDP (requiring an extra family) and with the forthcoming
QUIC (also requiring an extra family), especially since that binds them to
certain families, prevents them from supporting dgram UNIX sockets etc.
In order to address this, we now start to register the protocols with more
info, namely the socket type and the control type (either stream or dgram).
This is sufficient for the protocols we have to deal with, but could also
be extended further if multiple protocol variants were needed. But as is,
it still fits nicely in an array, which is convenient for lookups that are
instant.
We now take care of retrieving sock_family, l3_addrlen, bind(),
addrcmp(), get_src() and get_dst() from the protocol family and
not just the protocol itself. There are very few places, this was
only seldom used. Interestingly in sock_inet.c used to rely on
->sock_family instead of ->sock_domain, and sock_unix.c used to
hard-code PF_UNIX instead of using ->sock_domain.
Also it appears obvious we have something wrong it the protocol
selection algorithm because sock_domain is the one set to the custom
protocols while it ought to be sock_family instead, which would avoid
having to hard-code some conversions for UDP namely.
Now protocol_bind_all() starts the receivers before their respective
listeners so that ultimately we won't need the listeners for non-
connected protocols.
We still have to resort to an ugly trick to set the I/O handler in
case of syslog over UDP because for now it's still not set in the
receiver, so we hard-code it.
The receiver is the one which depends on the protocol while the listener
relies on the receiver. Let's move the protocol there. Since there's also
a list element to get back to the listener from the proto list, this list
element (proto_list) was moved as well. For now when scanning protos, we
still see listeners which are linked by their rx.proto_list part.
Ever since the protocols were added in 1.3.13, listeners used to be
started twice:
- once by start_proxies(), which iteratees over all proxies then all
listeners ;
- once by protocol_bind_all() which iterates over all protocols then
all listeners ;
It's a real mess because error reporting is not even consistent, and
more importantly now that some protocols do not appear in regular
proxies (peers, logs), there is no way to retry their binding should
it fail on the last step.
What this patch does is to make sure that listeners are exclusively
started by protocols. The failure to start a listener now causes the
emission of an error indicating the proxy's name (as it used to be
the case per proxy), and retryable failures are silently ignored
during all but last attempts.
The start_proxies() function was kept solely for setting the proxy's
state to READY and emitting the "Proxy started" message and log that
some have likely got used to seeking in their logs.
Similarly to previous commit about ->bind_all(), we have the same
construct for ->unbind_all() which ought not to be used either. Let's
make protocol_unbind_all() iterate over all listeners and directly
call unbind_listener() instead.
It's worth noting that for uxst there was originally a specific
->unbind_all() function but the simplifications that came over the
years have resulted in a locally reimplemented version of the same
function: the test on (state > LI_ASSIGNED) there is equivalent to
the one on (state >= LI_PAUSED) that is used in do_unbind_listener(),
and it seems these have been equivalent since at least commit dabf2e264
("[MAJOR] added a new state to listeners")) (1.3.14).
All protocols only iterate over their own listeners list and start
the listeners using a direct call to their ->bind() function. This
code duplication doesn't make sense and prevents us from centralizing
the startup error handling. Worse, it's not even symmetric because
there's an unbind_all_listeners() function common to all protocols
without any equivalent for binding. Let's start by directly calling
each protocol's bind() function from protocol_bind_all().
This patch fixes all the leftovers from the include cleanup campaign. There
were not that many (~400 entries in ~150 files) but it was definitely worth
doing it as it revealed a few duplicates.
And also rename standard.c to tools.c. The original split between
tools.h and standard.h dates from version 1.3-dev and was mostly an
accident. This patch moves the files back to what they were expected
to be, and takes care of not changing anything else. However this
time tools.h was split between functions and types, because it contains
a small number of commonly used macros and structures (e.g. name_desc)
which in turn cause the massive list of includes of tools.h to conflict
with the callers.
They remain the ugliest files of the whole project and definitely need
to be cleaned and split apart. A few types are defined there only for
functions provided there, and some parts are even OS-specific and should
move somewhere else, such as the symbol resolution code.
The protocol.h files are pretty low in the dependency and (sadly) used
by some files from common/. Almost nothing was changed except lifting a
few comments.
Half of the users of this include only need the type definitions and
not the manipulation macros nor the inline functions. Moves the various
types into mini-clist-t.h makes the files cleaner. The other one had all
its includes grouped at the top. A few files continued to reference it
without using it and were cleaned.
In addition it was about time that we'd rename that file, it's not
"mini" anymore and contains a bit more than just circular lists.
All files that were including one of the following include files have
been updated to only include haproxy/api.h or haproxy/api-t.h once instead:
- common/config.h
- common/compat.h
- common/compiler.h
- common/defaults.h
- common/initcall.h
- common/tools.h
The choice is simple: if the file only requires type definitions, it includes
api-t.h, otherwise it includes the full api.h.
In addition, in these files, explicit includes for inttypes.h and limits.h
were dropped since these are now covered by api.h and api-t.h.
No other change was performed, given that this patch is large and
affects 201 files. At least one (tools.h) was already freestanding and
didn't get the new one added.
Dragan Dosen found that the listeners lock is not sufficient to protect
the listeners list when proxies are stopping because the listeners are
also unlinked from the protocol list, and under certain situations like
bombing with soft-stop signals or shutting down many frontends in parallel
from multiple CLI connections, it could be possible to provoke multiple
instances of delete_listener() to be called in parallel for different
listeners, thus corrupting the protocol lists.
Such operations are pretty rare, they are performed once per proxy upon
startup and once per proxy on shut down. Thus there is no point trying
to optimize anything and we can use a global lock to protect the protocol
lists during these manipulations.
This fix (or a variant) will have to be backported as far as 1.8.
It's possible to have several protocols per family which is a problem
with the current way the protocols are stored.
This allows to register a new protocol in HAProxy which is not a
protocol in the strict socket definition. It will be used to register a
SOCK_STREAM protocol using socketpair().
Building 1.6 and above on OpenBSD 5.2 fails due to protocol.c not
including sys/types.h before sys/socket.h :
In file included from src/protocol.c:14:
/usr/include/sys/socket.h:162: error: expected specifier-qualifier-list before 'u_int8_t'
This fix needs to be backported to 1.6.
