The per-pt priv for event libs ended up overallocated at the context,
and pointed-to by a single pointer composed into each pt. That means
we can't do pointer arithmetic on it any more.
Update a couple of stragglers in libuv event lib to use a pointer in
the pt-priv for the event lib back to the pt instead.
Also in foreign case if we start idle, there may not be anything
happening to trigger the initial idle. So let each pt start with
its idle active.
This is complicated by the fact extern on a function declaration implies
visibility... we have to make LWS_EXTERN empty when building static.
And, setting target_compile_definitions() doesn't work inside macros,
so it has to be set explicitly for the plugins.
Checking the symbol status needs nm -C -D as per
https://stackoverflow.com/questions/37934388/symbol-visibility-not-working-as-expected
after this patch, libwebsockets.a shows no symbols when checked like that and
the static-linked minimal examples only show -U for their other dynamic
imports.
In a handful of cases we use LWS_EXTERN on extern data declarations,
those then need to change to explicit extern.
Before this we simply proxy the CREATING state from the proxy
version of the stream to the client version of the stream.
However this can result in disordering of onward connection
attempt request happening before the client has called back its
CREATING (*state()), meaning that any metadata set in the
state handler is missed for the onward connection.
This patch suppresses the CREATING forwarded from the proxy
and instead does its own local CREATING state callback at the
time the proxy indicates that the remote stream creation
(ie, with the requested policy streamtype) succeeded.
This then guarantees that the client has seen CREATING, and
had a chance to set metadata there, before the onward connection
request goes out. Since metadata has higher priority at the
writeable than the onward connection request it also means
any metadata set in client CREATING gets sync'd to the proxy
before the onward connection.
Formalize the LWSSSSRET_ enums into a type "lws_ss_state_return_t"
returned by the rx, tx and state callbacks, and some private helpers
lws_ss_backoff() and lws_ss_event_helper().
Remove LWSSSSRET_SS_HANDLE_DESTROYED concept... the two helpers that could
have destroyed the ss and returned that, now return LWSSSSRET_DESTROY_ME
to the caller to perform or pass up to their caller instead.
Handle helper returns in all the ss protocols and update the rx / tx
calls to have their returns from rx / tx / event helper and ss backoff
all handled by unified code.
Event lib support as it has been isn't scaling well, at the low level
libevent and libev headers have a namespace conflict so they can't
both be built into the same image, and at the distro level, binding
all the event libs to libwebsockets.so makes a bloaty situation for
packaging, lws will drag in all the event libs every time.
This patch implements the plan discussed here
https://github.com/warmcat/libwebsockets/issues/1980
and refactors the event lib support so they are built into isolated
plugins and bound at runtime according to what the application says
it wants to use. The event lib plugins can be packaged individually
so that only the needed sets of support are installed (perhaps none
of them if the user code is OK with the default poll() loop). And
dependent user code can mark the specific event loop plugin package
as required so pieces are added as needed.
The eventlib-foreign example is also refactored to build the selected
lib support isolated.
A readme is added detailing the changes and how to use them.
https://libwebsockets.org/git/libwebsockets/tree/READMEs/README.event-libs.md
Move the common plugin scanning dir stuff to be based on lws_dir, which
already builds for windows. Previously this was done via dirent for unix
and libuv for windows.
Reduce the dl plat stuff to just wrap instantiation and destruction of
dynlibs, establish common code in lib/misc/dir.c for plugin scanning
itself.
Migrate the libuv windows dl stuff to windows-plugins.c, so that he's
available even if later libuv loop support becomes and event lib plugin.
Remove the existing api exports scheme for plugins, just export a const struct
now which has a fixed header type but then whatever you want afterwards depending
on the class / purpose of the plugin. Place a "class" string in the header so
there can be different kinds of plugins implying different types exported.
Make the plugin apis public and add support for filter by class string, and
per instantation / destruction callbacks so the subclassed header type can
do its thing for the plugin class. The user provides a linked-list base
for his class of plugins, so he can manage them completely separately and
in user code / user export types.
Rip out some last hangers-on from generic sessions / tables.
This is all aimed at making the plugins support general enough so it can
provide event lib plugins later.
Add a minimal example showing how to write a binance client using
permessage_deflate and LCCSF_PRIORITIZE_READS to minimize latency.
This is partly informed by kutoga's example on
https://github.com/warmcat/libwebsockets/issues/2019 which was in
turn based on the existing ws client minimal example.
mbedtls has older and newer hashing apis, if we detected the newer ones
we use them like the older ones since generally, hashing doesn't have a
way to fail for sha and md5 update etc.
Coverity objects... change it to dumbly check the retcode.
Coverity sees we sometimes check if header length is 0 and extrapolates
from that not checking header length return is a violation. But often
we are OK if the header length is 0 and there is no error return to
check from that.
It also doesn't understand that if we saw a nonzero length for a header,
then we are going to get a non-null simple_ptr() return for sure. Just
give up and explicitly, unneccessarily check everything so coverity can
stop telling us about it.
