The persisted configuration subdirectory will be used to store changes to
the configuration. The gwdirs.h header now supports setting and getting
the value for this directory.
The address, port, monuser and monpw parameters of an existing server can
be changed at runtime. The support for enabling SSL will come in a later
commit.
Allowing servers to be modified could also be done by destroying and
recreating them. Since the servers are never actually destroyed, it is
better to allow the alteration of the existing ones.
The `add server` command accepts a server name and either a service name
or a monitor name. It will add servers to services and monitors. Since all
monitors use the MONITOR_SERVER structures directly, the monitors need
to be stopped before new servers are added to them
The function serializes a server to a file. This is intended to be used
with dynamically created servers. The output of the server serialization
will eventually be stored in the configuration file directory (default is
/etc/maxscale.cnf.d/) so that created servers persist even after a
restart.
The BACKEND structure in readconnroute is now replaced with the use of the
SERVER_REF structure of the service. This allows dynamic changes to the
list of servers to be made.
Servers can now be added and removed from services which allows routers to
use them with new sessions. The routers don't fully use the new
functionality in the server references which prevents new servers from
being taken into use.
If shutdown has been initiated (via maxadmin or by sending a
SIGINT or SIGTERM) and a SIGTERM is received, the process
is terminated.
If shutdown has been initiated (via maxadmin or by sending a
SIGINT or SIGTERM) and a SIGINT (Ctrl-C) is received, a warning
is printed that shutdown is in progess. Then, if an additional
SIGINT is received, the process is terminated.
So, in practice:
- If MaxScale is running as a daemon, the first SIGTERM initiates
shutdown and a second one unconditionally terminates the process.
- If MaxScale is running in the console, the first Ctrl-C initiates
shutdown, the second prints a warning and the third terminates
the process.
This is to ensure that MaxScale can be forced to exit, in
case some thread is hung for whatever reason, and is thus preventing
the controlled shutdown.
This allows safer lock-free reads to be done on lists that never shrink in
size. The main use-case for this is to allow servers to be added to a
service without locking the service each time a new session is created.
Synchronizing the memory before adding new components into a list
guarantees that if a session reads from the list and sees the new list
item, the memory pointed by the item is valid.
Function is no longer used and it was quite unoptimal, so now
removed.
qc_get_prepare_name, qc_get_prepare_operation and qc_get_field_info
that were missing from qc_dummy added at the same time.
This function returns more detailed information about the fields
of a statement. Supersedes qc_get_affected_fields() that will
be deprecated and removed.
Note that this function now introduced new kind of behaviour; the
returned data belongs to the GWBUF and remains valid for as long as
the GWBUF is alive. That means that unnecessary copying need not
be done.
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 operation of the statement to be prepared is no longer
reported as the operation of the PREPARE statement.
Instead, when the type of the statement is
QUERY_TYPE_PREPARE_NAMED_STMT, the operation can be obtained
using qc_get_prepare_operation().
The qc_mysqlembedded implementation will be provided in a
subsequent commit.
The transaction state only reflects explicitly started transactions.
Thus, by looking at the autocommit mode and the transaction state a
component can figure out whether the current statement will be committed
or not.
The transaction state must be updated after a buffer has been split
into buffer containing individual packets.
NOTE: The actual updating of the transaction state and the autocommit
mode is currently wrong, but will be updated in a subsequent change.
With this change, whether something should be logged or, that is,
whether the used log priority is enabled or not, is checked before
the logging function is called. That should save a few cycles.
Now mxs_log_message() always logs a message, without consideration
for whether the priority is enabled or not. The inline function
mxs_log_is_priority_enabled() returns true if a particular priority
is enabled and the MXS_LOG_MESSAGE() macro (that MXS_ERROR etc. are
expanded into) call that before calling the actual logging function.
Common capabilities are now defined in routing.h. The common
capabilities can be defined using bits 0 - 15.
Router capabilities are defined using bits 16-31 and filter
capabilities (should there ever be such) using bits 32-47.
So, to find out the capabilities of a service you only need to
OR the capabilities of the router and all filters together.
For instance, if a single filter needs statement based routing,
then that is what is done.
The path that was given as the option for the cache directory wasn't
properly checked for terminating forward slashes. Due to this, the cache
file was created with the wrong name.
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.
The MySQL authenticator now injects the service user into the list of
allowed users if loading of database users fails. This allows the removal
of common code in the binlogrouter and maxinfo modules.
This tracks only what is explicitly set. That is, if autocommit
has been set true then, even if a transaction is started, autocommit
will not be set false.
That is, a user of the session autocommit and transaction states
need to be aware of their semantics. If a transaction is active,
then the state of autocommit is irrelevant.
- Since the capabilities are a bitmask, it is better if an unsigned
integral type is used.
- Since the function is part of an ABI, it is better if an explicit
size is used.
- 64-bits so that there also is room for independent filter
capabilities.
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.
MAX_BUFFER_SIZE, which is used for limiting the amount of the data
read from a socket renamed to MXS_MAX_NW_READ_BUFFER_SIZE and moved
from gw.h to limits.h.
Consider removing altogether. Difficult to justify since non-blocking
reads are used and the amount of available data is known.
