Failing to connect would release parts of the MYSQL struct.
We would then proceed to try again to connect without re-
initializing the struct.
We prevent the unwanted freeing of data we'll still need now.
with gcc 4.3.2
This patch fixes a number of GCC warnings about variables used
before initialized. A new macro UNINIT_VAR() is introduced for
use in the variable declaration, and LINT_INIT() usage will be
gradually deprecated. (A workaround is used for g++, pending a
patch for a g++ bug.)
GCC warnings for unused results (attribute warn_unused_result)
for a number of system calls (present at least in later
Ubuntus, where the usual void cast trick doesn't work) are
also fixed.
Bug#45243: crash on win in sql thread clear_tables_to_lock() -> free()
Bug#45242: crash on win in mysql_close() -> free()
Bug#45238: rpl_slave_skip, rpl_change_master failed (lost connection) for STOP SLAVE
Bug#46030: rpl_truncate_3innodb causes server crash on windows
Bug#46014: rpl_stm_reset_slave crashes the server sporadically in pb2
When killing a user session on the server, it's necessary to
interrupt (notify) the thread associated with the session that
the connection is being killed so that the thread is woken up
if waiting for I/O. On a few platforms (Mac, Windows and HP-UX)
where the SIGNAL_WITH_VIO_CLOSE flag is defined, this interruption
procedure is to asynchronously close the underlying socket of
the connection.
In order to enable this schema, each connection serving thread
registers its VIO (I/O interface) so that other threads can
access it and close the connection. But only the owner thread of
the VIO might delete it as to guarantee that other threads won't
see freed memory (the thread unregisters the VIO before deleting
it). A side note: closing the socket introduces a harmless race
that might cause a thread attempt to read from a closed socket,
but this is deemed acceptable.
The problem is that this infrastructure was meant to only be used
by server threads, but the slave I/O thread was registering the
VIO of a mysql handle (a client API structure that represents a
connection to another server instance) as a active connection of
the thread. But under some circumstances such as network failures,
the client API might destroy the VIO associated with a handle at
will, yet the VIO wouldn't be properly unregistered. This could
lead to accesses to freed data if a thread attempted to kill a
slave I/O thread whose connection was already broken.
There was a attempt to work around this by checking whether
the socket was being interrupted, but this hack didn't work as
intended due to the aforementioned race -- attempting to read
from the socket would yield a "bad file descriptor" error.
The solution is to add a hook to the client API that is called
from the client code before the VIO of a handle is deleted.
This hook allows the slave I/O thread to detach the active vio
so it does not point to freed memory.
The problem is that the C API function mysql_real_connect
only attempts to connect to the first IP address returned
for a hostname. This can be a problem if a hostname maps
to multiple IP address and the server is not bound to the
first one that is returned.
The solution is to augment mysql_real_connect so that it
attempts to connect to all IPv4 addresses that a domain
name maps to. The function goes over the list of address
until a successful connection is established.
No test case is provided as its not possible to test this
automatically with the current testing infrastructure.
Backport to MySQL 5.0/1 fix by Vladislav Vaintroub:
In Vista and later and also in when using terminal services, when
server is started from command line, client cannot connect to it
via shared memory protocol.
This is a regression introduced when Bug#24731 was fixed. The
reason is that client is trying to attach to shared memory using
global kernel object namespace (all kernel objects are prefixed
with Global\). However, server started from the command line in
Vista and later will create shared memory and events using current
session namespace. Thus, client is unable to find the server and
connection fails.
The fix for the client is to first try to find server using "local"
names (omitting Global\ prefix) and only if server is not found,
trying global namespace.
in load_defaults()
load_defaults(), my_search_option_files() and
my_print_default_files() utilized a global variable
containing a pointer to thread local memory. This could lead
to race conditions when those functions were called with high
concurrency.
Fixed by changing the interface of the said functions to avoid
the necessity for using a global variable.
Since we cannot change load_defaults() prototype for API
compatibility reasons, it was renamed my_load_defaults().
Now load_defaults() is a thread-unsafe wrapper around
a thread-safe version, my_load_defaults().
- Remove bothersome warning messages. This change focuses on the warnings
that are covered by the ignore file: support-files/compiler_warnings.supp.
- Strings are guaranteed to be max uint in length
- Remove bothersome warning messages. This change focuses on the warnings
that are covered by the ignore file: support-files/compiler_warnings.supp.
- Strings are guaranteed to be max uint in length
The problem was that the COM_STMT_SEND_LONG_DATA was sending a response
packet if the prepared statement wasn't found in the server (due to
reconnection). The commands COM_STMT_SEND_LONG_DATA and COM_STMT_CLOSE
should not send any packets, even error packets should not be sent since
they are not expected by the client API.
The solution is to clear generated during the execution of the aforementioned
commands and to skip resend of prepared statement commands. Another fix is
that if the connection breaks during the send of prepared statement command,
the command is not sent again since the prepared statement is no longer in the
server.
in some case.
ER_CON_COUNT_ERROR is defined with SQL state 08004. However, this SQL state is not always
returned.
This error can be thrown in two cases:
1. when an ordinary user (a user w/o SUPER privilege) is connecting,
and the number of active user connections is equal or greater than
max_connections.
2. when a user is connecting and the number of active user connections is
already (max_connections + 1) -- that means that no more connections will
be accepted regardless of the user credentials.
In the 1-st case, SQL state is correct.
The bug happens in the 2-nd case -- on UNIX the client gets 00000 SQL state, which is
absolutely wrong (00000 means "not error SQL state); on Windows
the client accidentally gets HY000 (which means "unknown SQL state).
The cause of the problem is that the server rejects extra connection
prior to read a packet with client capabilities. Thus, the server
does not know if the client supports SQL states or not (if the client
supports 4.1 protocol or not). So, the server supposes the worst and
does not send SQL state at all.
The difference in behavior on UNIX and Windows occurs because on Windows
CLI_MYSQL_REAL_CONNECT() invokes create_shared_memory(), which returns
an error (in default configuration, where shared memory is not configured).
Then, the client does not reset this error, so when the connection is
rejected, SQL state is HY000 (from the error from create_shared_memory()).
The bug appeared after test case for Bug#33507 -- before that, this behavior
just had not been tested.
The fix is to 1) reset the error after create_shared_memory();
2) set SQL state to 'unknown error' if it was not received from
the server.
A separate test case is not required, since the behavior is already
tested in connect.test.
Note for doc-team: the manual should be updated to say that under
some circumstances, 'Too many connections' has HY000 SQL state.
Rename client_last_error to last_error and client_last_errno to last_errno
to not break connectors which use the internal net structure for error handling.
There was no way to return an error from the client library
if no MYSQL connections was established.
So here i added variables to store that king of errors and
made functions like mysql_error(NULL) to return these.
--local-infile=0 checks can be bypassed by sending a FETCH LOCAL FILE response
Add a check for CLIENT_LOCAL_FILES before sending a local file.
Beware, that all binary distributions enable sending of local files and it's up
to the programs which use libmysql to disable it, if they don't use this functionality.
Otherwise they are not safe.
cause ROLLBACK of statement", part 1. Review fixes.
Do not send OK/EOF packets to the client until we reached the end of
the current statement.
This is a consolidation, to keep the functionality that is shared by all
SQL statements in one place in the server.
Currently this functionality includes:
- close_thread_tables()
- log_slow_statement().
After this patch and the subsequent patch for Bug#12713, it shall also include:
- ha_autocommit_or_rollback()
- net_end_statement()
- query_cache_end_of_result().
In future it may also include:
- mysql_reset_thd_for_next_command().
No functionality added or changed.
This is a pre-requisite for the fix for Bug#12713 Error in a stored
function called from a SELECT doesn't cause ROLLBACK of statem
Address post-review comments.
Faster thr_alarm()
Added 'Opened_files' status variable to track calls to my_open()
Don't give warnings when running mysql_install_db
Added option --source-install to mysql_install_db
I had to do the following renames() as used polymorphism didn't work with Forte compiler on 64 bit systems
index_read() -> index_read_map()
index_read_idx() -> index_read_idx_map()
index_read_last() -> index_read_last_map()
--long-query-time is now given in seconds with microseconds as decimals
--min_examined_row_limit added for slow query log
long_query_time user variable is now double with 6 decimals
Added functions to get time in microseconds
Added faster time() functions for system that has gethrtime() (Solaris)
We now do less time() calls.
Added field->in_read_set() and field->in_write_set() for easier field manipulation by handlers
set_var.cc and my_getopt() can now handle DOUBLE variables.
All time() calls changed to my_time()
my_time() now does retry's if time() call fails.
Added debug function for stopping in mysql_admin_table() when tables are locked
Some trivial function and struct variable renames to avoid merge errors.
Fixed compiler warnings
Initialization of some time variables on windows moved to my_init()
unpack_fields() didn't expect NULL_LENGHT in the field's descriptions.
In this case we get NULL in the resulting string so cannot use
strdup_root to make a copy of it.
strdup_root changed with strmake_root as it's NULL-safe
If one sets MYSQL_READ_DEFAULTS_FILE and MYSQL_READ_DEFAULT_GROUP options
after mysql_real_connect() called with that MYSQL instance,
these options will affect next mysql_reconnect then.
As we use a copy of the original MYSQL object inside mysql_reconnect,
and mysql_real_connect frees options.my_cnf_file and _group strings,
we will free these twice when we execute mysql_reconnect with the
same MYSQL for the second time.
I don't think we should ever read defaults files handling mysql_reconnect.
So i just set them to 0 for the temporary MYSQL object there/
long shared-memory-base-names could overflow a static internal buffer
and thus crash mysqld and various clients. change both to dynamic
buffers, show everything but overflowing those buffers still works.
The test case for this would pretty much amount to
mysqld --shared-memory-base-name=HeyMrBaseNameXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX --shared-memory=1 &
mysqladmin --no-defaults --shared-memory-base-name=HeyMrBaseNameXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX shutdown
Unfortunately, we can't just use an .opt file for the
server. The .opt file is used at start-up, before any
include in the actual test can tell mysqltest to skip
this one on non-Windows. As a result, such a test would
break on unices.
Fixing mysql-test-run.pl to export full path for master
and slave would enable us to start a server from within
the test which is ugly and, what's more, doesn't work as
the server blocks (mysqltest offers no fire-and-forget
fork-and-exec), and mysqladmin never gets run.
Making the test rpl_windows_shm or some such so we can
is beyond ugly. As is introducing another file-name based
special case (run "win*.test" only when on Windows). As is
(yuck) coding half the test into mtr (as in, having it
hand out a customized environment conductive to the shm-
thing on Win only).
Situation is exacerbated by the fact that .sh is not
necessary run as expected on Win.
In short, it's just not worth it. No test-case until we
have a new-and-improved test framework.
- Add build configuration parameter EMBEDDED_ONLY which will configure
the VS solution to produce only mysql embedded binary.
- Make necessary updates to successfully compile solution.
