Closer is a template using which C-style resources can be managed
in a C++ context where exceptions can occur. By placing a C resource
in a Closer instance, it is certain the resource will be freed when
the closing scope is exited irrespective of whether that occurs due
to the normal control flow, due to a return statement or an exception
having been thrown.
To be used with Closer, the CloserTraits template must be specialized
for the type in question. With this change specializations are provided
for FILE*, json_t*, pcre_code* and pcre2_match_data*.
The setting up and the initialization of the query classifier has
now been separated. The gateway explicitly sets up the query
classifier (i.e. chooses which one to use and what arguments to
provide), but the actual initialization is performed as part of
the general module initialization.
The filters should use the same configuration parameters as other modules
use. This allows them to use the common configuration management functions
to get values from it.
If the enums are converted to the acutual enum values before they are
returned, this removes the need for the modules to process the enum
strings to enum values. This allows modules to use enumerations with
minimal effort.
The MXS_MODULDE object now contains optinal pointers for functions
to be called att process and thread startup and shutdown. Since the
functions were added to the end, strictly speaking, all structures
would not have needed to have been modified, but better to be
explicit. In a subsequent change, these will be called.
C++ does not support flexible arrays, so for the time being C++
modules are restricted to 10 parameters. Better approach is to
factor out the parameters to a separate array and then just store
a pointer to that array in MXS_MODULE.
The path type is validated if the module requested path
validation. Service checks can be done both on startup and at
runtime. This allows dynamic changes to module parameters to be validated
without a configuration context.
The options allow the modules to impose type specific restrictions on the
parameters. This can be used to offload file permission and mandatory
parameter checks to the core.
The declared parameters are now used to check whether the configuration is
valid. As the filters and monitors don't use the new declarations, the
code needs to be commented out. Once the parameter processing has been
migrated to the new system, the code can be enabled.
The MXS_MODULE structure now contains a member for parameters. This can be
used by the modules to declare accepted parameters, their types and the
default values. Currently only count, integer, boolean, string and enum
values are supported.
The MXS_MODULE structure of each module is now globally exposed by the
`get_module` function. This allows the module information of any module to
be queried.
This information can then be used to validate various things but the main
goal is to provide a way for modules to declare accepted parameters in the
MXS_MODULE structure. This will be done in a later commit.
Also the function documentation is now in the header file. This should
make it easier to read.
The MODULE_INFO is now the main object which is used by modules to convey
information to the MaxScale core. The MXS_MODULE name is more apt as it
now contains the actual module definition.
The old MODULES structure was moved into load_utils.c as an internal
implementation and was renamed so that it is not confused with the new
MODULE structure.
The modules are now declared with a common macro. This allows future
additions to the module loading process while also making the loaded
symbol name a constant.
This allows modules to only expose one entry point with a consistent
signature. In the future, this could be used to implement declarations of
module parameters.
- Rename session_getUser to session_get_user
- Change session_get_user and session_get_remote to take a const
SESSION* as argument and to return a const char*.
- Change server_get_persistent, so that user is passed as const.
- Update all users of these functions as appropriate.
maxscale::Buffer is a simple C++ wrapper around GWBUF that allows the
latter to be manipulated like an STL compatible collection.
maxscale::Buffer provides both a const and non-const forward iterator,
using which a non-contiguous GWBUF can be traversed and manipulated.
The iterators can be used with any standard C++ algorithm that accepts
forward iterators.
The function is not capable of doing the right thing for an entire
account string, but only separately for user and host names, so the
function name should reflect that.
Function for removing MySQL quote characters surrounding a
string moved from Cache's rules.cc to common place and renamed.
The function was now moved to mysql_utils.[h|c], which is in
maxscale-common, and not to the perhaps more appropriate place
protocol/mysql.h, as the latter would have implied that MySQLCommon
would have to be linked to, which actually might be the right thing
to do. However, that has to wait until protocol/mysql.h gets an
overhaul.
The server weighting parameters couldn't be altered online and they
weren't serialized to disk. Only servers that are created online will have
their weighting parameters persisted to disk.
Any changes to servers that aren't created online need to be manually
added to the configuration file in order for them to take effect after the
restart.
- Move docs from buffer.c to buffer.h
- Arguments made const-correct.
gwbuf_length
gwbuf_count
gwbuf_copy_data
- Boolean return values changes from int to bool.
gwbuf_add_property
- Meaningless returnvalue changed from int to void.
gwbuf_add_hint
- Unused function removed.
gwbuf_clone_transform
gwbuf_trim
gwbuf_clone cloned only the first buffer of a chain of buffers,
which never can be the desired outcome, while gwbuf_clone_all
cloned all buffers.
Now, gwbuf_clone behaves the way gwbuf_clone_all used to behave
and gwbuf_clone_all has been removed.
The DECIMAL value type is now properly handled in Avrorouter. It is
processed into an Avro double value when before it was ignored and
replaced with a zero integer.
Previously, server status changes from MaxAdmin would be set immediately
as long as the server lock could be acquired. This meant that it might take
several seconds until the next monitor pass is executed. Usually, this was
fine but in some situations we would want the monitor to run immediately
after the change (MXS-740 and Galera). This patch changes the logic of
setting and clearing status bits to a delayed mode: changes are first applied
to a "status_pending"-variable, and only once the monitor runs will the
setting be applied. To reduce the delay, the monitor now has a flag
which is checked during sleep (between short 0.1s naps). If set, the
sleep is cut short.
If a server is not monitored, the status bits are set directly.
There is a small possibility of a race condition: If a monitor is stopped or
destroyed before the pending change is applied, the change is forgotten.
Diagnostics can be required on both instance and session level,
so both cases need to be handled explicitly.
In addition, some reinterpret_casts were changed into static_casts.
Reinterpret_cast needs to be used with the instance, which is a
void** but static_cast is sufficient for the session, which is void*.
When the listeners were created twice, MaxScale would crash when the users
were loaded. This is caused by the fact that the DCB for the listener is
NULL for failed listeners.
