This allow clients to access their SSL structure and
perform additional verification.

These can be used by plugins to disconnect clients.

This is in preparation for changing to a tree based implementation.

Websockets clients are now part of the by_sock hashtable, so this isn't
needed.

These are for field width and precision for some parameters.

We always get passed the client even if it doesn't have a
username/password now.

If we have e.g. max_inflight_messages set to 1000, and currently have 999 messages inflight, then when we send a new message to a client we have to iterate over the whole list to get to the newest message. This change means that we start of the back of the list to find the newest items, which reduces overhead.

New messages are now queued for clients when old ones are sent, rather than on every iteration of the main loop. This produces good performance improvements.

This should allow tests to be simpler - no more nested ifs.

Rename mosquitto_plugin_publish() to mosquitto_broker_publish().

These two functions achieve the same thing. *_publish() publishes the payload and frees it later. *_publish_copy() takes a copy of the payload, so the plugin still owns the memory it passed to the function.

Coverity Scan 1431137.

Coverity Scan 1431139.

Coverity Scan 1431132.

Coverity Scan 1431134, 1431136, 1431140.

Coverity Scan 1431131, 1431135, 1431141.