Preparation for adding KILL syntax support.
Session id changed to uint32 everywhere. Added atomic op.
Session id can be acquired before session_alloc().
Added session_alloc_with_id(), which is given a session id number.
Worker object has a session_id->SESSION* mapping, not used yet.
The backend MySQL protocol can now collect prepared statement preparation
responses as well as result sets. This removes the need to parse and
collect the preparation responses at the router level.
The functions used to track the resultset EOF packets now expose the
position of the end of the result set. This allows the modules that use
them to check if more results exist in the same buffer.
Added the status bits for OK and EOF packets to the mysql.h protocol
header. This can be used to check for various state changes that happen in
the session. Currently the status bits are only used to detect if more
results are expected.
When batched queries are done through readwritesplit, it will now handle
them one by one. This allows batched queries to be used with
readwritesplit but it does impose a performance penalty when compared to
direct execution on the backend.
New parameter added to maxsrows filter:
max_resultset_return=empty|error|ok
Default, 'empty' is to return an empty set, as the current
implementation.
'err' will return an ERR reply with the input SQL statement
'ok' will return an OK packet
The new type allows routers to send queries and get complete result sets
as a response. This allows the routers to easily send commands that create
result sets and which are parsed by the router.
Currently only the schemarouter benefits from this new capability as it
generates the database mappings by parsing the output of a SHOW DATABASES
query.
Some of the protocol modules use ssize_t instead of size_t.
Split the function that counts the number of response packets a session
command will receive into two parts. This allows it to be reused
elsewhere.
The readwritesplit now sends COM_PING queries to backend servers that have
been idle for too long. The option is configured with the
`connection_keepalive` parameter.
The client protocol module can resolve whether a password was used based
on the information the authenticators gather before authentication is
done. It uses the authentication token length as the basis on which it
makes the decision.
Removed unused spinlocks from DCBs, sessions and the MySQL protocol
structs. They were used in a context where only one thread has access to
the structure.
Removed unused member variables from DCBs.
The backend MySQL protocol module now supports a new routing capability
which allows result sets to be gathered into one buffer before they are
routed onward. This should not be used by modules that expect large
result sets as the result set is buffered in memory.
Adding a limit on how large of a result set could be buffered would allow
relatively safe use of this routing capability without compromising the
stability of the system.
The packet was generated with the wrong number of elements due to usage of
sizeof on an integer where the correct type was an uint8_t.
This only fixes the malformed packets but does not fix the root cause of
the problem. The affected rows and last insert ID are length encoded
integers which should be handled. The current code treats them as one byte
fields.
To prevent bugs caused by pointers having the wrong type (e.g. uint32_t
instead of uint8_t), some macros are changed into inline functions so that
the normal type-checking is performed.
The macros MYSQL_GET_ERRCODE, MYSQL_GET_STMTOK_NPARAM, MYSQL_GET_STMTOK_NATTR,
and MYSQL_GET_NATTR were not changed, because they may be too specific to
be present in a general purpose header in the first place.
When a persistent connection is taken from the pool, the state is reset
with a COM_CHANGE_USER on the next write. This allows reuse of persistent
connections without having to worry about the state of the MySQL session.
The dbusers.c was a MySQL protocol specific file which was used directly
by some of the modules.
Added a new return value for the loadusers authenticator entry point which
allows fatal failures to occur when users are loaded. Currently this is
only taken into notice when the service is first started. If a listener
later returns a fatal error, it is only logged but the service stays in
operation.
Moved the MySQLAuth authenticator sources and the tests that relate to
this module into a subdirectory in the authenticator
directory. Eventually, all authenticators could have a subdirectory of
their own.
In a subsequent change, the includes of server/core/*.c will be
cleaned up, and if there is a common set of include files, needed
by most, then a server/core/maxscale/core.h that includes those
will be introduced.
Made the packet sequence number handling automatic so that it always uses
the correct one.
All functions now have documentation in them. Cleaned up code and added
comments to GSSAPI code.
