All GWBUF macros that address a single link in a chain are now
simple wrappers for equivalent gwbuf_link-functions.
Next step is to drop the macros and replace their use with calls
to the functions.
Added core functionality for UNIX domain sockets in servers. Currently the
address parameter accepts them both but a separate `socket` parameter is
needed.
If a DCB was closed and a hangup event was sent to it via
dcb_hangup_foreach shortly after it was closed, the DCB would still
receive it even if it was closed. To prevent this, events must only be
delivered to DCBs if they haven't been closed.
The protocol should not track the session state as the parsing is quite
expensive with the current code. This change is a workaround that enables
the parsing only when required. A proper way to handle this would be to do
all the response processing in one place thus avoiding the duplication of
work.
If an ignorable packet was followed by more than one queued packets, they
would all get routed in the same batch. This would cause unexpected
replies from the server if multiple ignorable packets were queued up.
If the connection to the master is lost, knowing what type of an error
caused the call to handleError helps deduce what was the real reason for
it. Logging the idle time of the connection helps detect when the
wait_timeout of a connection is exceeded.
Most of the ones still remaining outside are special cases.
Also, removed locking from status manipulation functions as it
has not been required for quite some time.
DCBs can now have a null session pointer and if they do, they are in the
persistent pool. The no-null-session assertions are no longer valid but
with a reorganization of the pooling code to only use file descriptors,
the assertions can be added back.
Minor renaming of the session state enum values. Also exposed the session
state stringification function in the public header and removed the
stringification macro.
The error flag was set before the function was called which caused the
function to never be used. As the core should handle the filtering of
multiple errors on the same DCB, the protocol modules should not check it.
When a response to a prepared statement was processed, the number of EOF
packets was used to see whether the response was complete. This code used
a function that does not work with the special packet returned by a PS
preparation that is similar to an OK packet.
The correct method is to count the total number of packets in the
response.
As each connection now immediately gets a session the dummy session is no
longer required. The next step would be to combine parts of the session
and the client DCB into one entity. This would prevent the possibility of
a client DCB with no associated session. Backend DCBs are different as
they can move from one session to another when the persistent connection
pool is in use.
The collection of resultsets needs to be disabled by default when a
response is received to cover the cases where an error is returned.
The collection of results should also not be set for queries that do not
generate any responses.
