When persistent connections were used, it was possible that the injection
of COM_CHANGE_USER statements caused a crash when a DCB in the wrong state
was accessed.
For MySQL protocol modules, the `data` member of the client DCB points to
the shared session data, a MYSQL_session struct, but for sessions in the
persistent pool, it points to NULL. The boolean, `was_persistent`, tells
whether a DCB was just taken from the pool or it has been in use.
The `was_persistent` status wasn't properly reset for connections that
were put into the pool which caused a COM_CHANGE_USER statement to be
injected for stale connections in the pool which caused a crash when the
NULL `data` member was accessed.
Previously the session_id incrementation was done after creating
filters, giving the filters a constant zero value for session_id.
Now the incrementation happens before filter creation.
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.
The check for the success of the configuration file always resulted in a
successful return value even if the loading failed.
In addition to this, a log message referred to the active configuration
when the active configuration was set only after the processing was
complete. Since configuration failures are always fatal, there's no harm
in preemptively setting the active configuration to the one currently
being processed.
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.
Given a config file "config.cnf", we look for the directory
"config.cnf.d" and recursively in that hierarhcy load all files
whose suffix is ".cnf"; other files are ignored.
Currently duplicate sections are checked on a file by file basis.
That will be changed so that duplicate sections are not allowed
across all the files.
- First <maxscale/cdefs.h>
- Then all system, c-runtime, OS include files in alphabetical order.
- Then include files for "3rd-party" software in a loose order of
importance.
- Then maxscale headers ordered alphabetically.
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.
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.
Some of the tests depended on a working installation where modules are all
located at the default paths. These tests now explicitly set the module
directory which fixes the immediate problem.
Disabled the starting of services in the service test as this will fail
with real modules. The dummy internal modules aren't build and should be
removed in a later commit. In general, it might be better to do service
level testing outside the internal test suite.
The HTTPD protocol mistakenly assumed that the `authenticator` parameter
of a listener would be NULL if the default authenticator is used.
Recent changes modified it so that the value is never NULL and
`NullAuthDeny` would be used for protocols which did not implement the
auth_default entry point.
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.
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.
Gw.h contained a fair amount of obsolete function declarations,
duplicate declarations of functions declared in utils.h and
declarations of functions that conceptually are similar to those
in utils.h.
The obsolete and duplicate ones were removed and all but one of
the remaining moved to utils.h. Correspondingly the implementation
was moved from gw_utils.c to utils.c.
The one remaining function - gw_daemonize() - is not really worthy
of a file of its own, so that is to be moved to gateway.c after which
gw_utils.c can be removed.
Gw.h still contains defines that are duplicated in
maxscale/protocol/mysql.h. The ones in gw.h are to be removed. It
appears that the entire gw.h will disappear.
The general purpose stuff in skygw_utils.h was moved to utils.h
and the corresponding implementation from skygw_utils.cc to utils.c.
Includes updated accordingly.
Skygw_utils.h is now only used by log_manager and by mlist, which
is only used by log_manager. Consequently, skygw_utils.h was moved
to server/maxscale.
Utils.h needs a separate overhaul.
- STRERROR_BUFLEN moved to cdefs.h and renamed to MXS_STRERROR_BUFLEN.
Better would be to provide a 'const char* mxs_strerror(int errno)'
that would have a thread specific buffer for the error message.
- MIN and MAX also moved to defs.h as MXS_MIN and MXS_MAX.
- Now only mlist.h of the headers depend upon skygw_utils.h.
- All now include maxscale/cdefs.h as the very first file.
- MXS_[BEGIN|END]_DECLS added to all C-headers.
Strictly speaking not necessary for private headers, but
does not hurt either.
- Include guards moved to the very top of the file.
- #pragma once added.
