Rewrite HMAC stuff to use HMAC_ apis instead of EVP
Bit trickly since modern OpenSSL has opaque HMAC_CTX and older
OpenSSL does not have any apis to allocate and free it.
Add another cmake check for the allocation api to decide
what to do.
https://github.com/warmcat/libwebsockets/issues/1625
"dead bodies" that were sent but not processed by lws as server
will clog up and destroy transaction tracking if repeated POSTs
with keepalive are sent to nonexistant paths.
This patch introduces a DISCARD_BODY state that follows BODY
except the payload is not signalled to the protocol callback.
Calling transaction_completed() with pending body makes lws
enter DISCARD_BODY and retry transaction completed only after
the pending body is exhausted.
When creating a vhost and the port is already bound to another process
this flag would allow the user code to choose to have the
lws_create_vhost function to fail and return a null pointer.
Otherwise it often forgets to inform about event loop interrupts. Add a flag to the per thread context, set it in the signal function, then check / reset it in the service method.
SMTP was improved to use the new abstract stuff a while ago,
but it was only implemented with raw socket abstract transport,
and a couple of 'api cheats' remained passing network information
for the peer connection through the supposedly abstract apis.
This patch adds a flexible generic token array to supply
abstract transport-specific information through the abstract apis,
removing the network information from the abstract connect() op.
The SMTP minimal example is modified to use this new method to
pass the network information.
The abstract transport struct was opaque, but there are real
uses to override it in user code, so this patch also makes it
part of the public abi.
