Bug#11761576 54082: HANDLE_SEGFAULT MAKES USE OF UNSAFE FUNCTIONS

handle_segfault is the signal handler code of mysqld.  however, it makes
calls to potentially unsafe functions localtime_r, fprintf, fflush.



include/my_stacktrace.h:
  Add safe versions of itoa() write() and snprintf().
libmysqld/CMakeLists.txt:
  Move signal handler to separate file.
mysys/stacktrace.c:
  Remove unsafe function calls.
sql/CMakeLists.txt:
  Move signal handler to separate file.
sql/Makefile.am:
  Move signal handler to separate file.
sql/mysqld.cc:
  Move signal handler to separate file.
sql/signal_handler.cc:
  Remove unsafe function calls.

There was memory leak when running some tests on PB2.
The reason of the failure is an early return from change_master()
that was supposed to deallocate a dyn-array.

Fixed with relocating the dyn-array's destructor at ~LEX() that is
the end of the session, per Gleb's patch idea.
Two optimizations were done: the static buffer for the dyn-array to base on,
and the array initialization is called precisely when it's necessary rather than
per each CHANGE-MASTER as before.
 

mysql-test/suite/rpl/t/rpl_empty_master_host.test:
  the test is binlog-format insensitive so it will be run with MIXED mode only.
sql/sql_lex.cc:
  the new flag is initialized.
sql/sql_lex.h:
  A new bool flag new member to LEX.mi is added to stay UP since after
  LEX.mi.repl_ignore_server_ids dynarray initialization was called
  for the first time on the session. So it is set once and its life time 
  is session.
  
  The array is destroyed at the end of the session.
sql/sql_repl.cc:
  dyn-array destruction is relocated to ~LEX.
sql/sql_yacc.yy:
  Refining logics of Lex->mi.repl_ignore_server_ids initialization.
  The array is initialized once a corresponding option in CHANGE MASTER token sequence
  is found.
  The fact of initialization is memorized into the new flag.

readline.cc: In function char* batch_readline(LINE_BUFFER*):
readline.cc:60:9: error: out_length may be used uninitialized in this function
log.cc: In function int find_uniq_filename(char*):
log.cc:1857:8: error: number may be used uninitialized in this function

Automerged approved bzr bundle into latest mysql-5.5.

                    WITH MYISAM_USE_MMAP ENABLED

MySQL server can crash due to segmentation fault when
started with myisam_use_mmap.

The reason behind this being, while making a request to
unmap (munmap) the previously mapped memory (mmap), the
size passed was 7 bytes larger than the size requested at
the time of mapping. This can eventually unmap the adjacent
memory mapped block, belonging to some other memory-map pool.
Hence the subsequent call to mmap can map a region which was
still a valid memory mapped area.

Fixed by removing the extra 7-byte margin which was erroneously
added to the size, used for unmappping.


storage/myisam/mi_close.c:
  Bug#11756764 48726: MYSQLD KEEPS CRASHING WITH SIGSEGV
                      WITH MYISAM_USE_MMAP ENABLED
  
  Added a condition to call _mi_unmap_file() in case
  of compressed records. mi_munmap_file() is called
  otherwise.
storage/myisam/mi_packrec.c:
  Bug#11756764 48726: MYSQLD KEEPS CRASHING WITH SIGSEGV
                      WITH MYISAM_USE_MMAP ENABLED
  
  mi_dynmap_file() function, after successfully executing
  mmap, stores the total size in info->s->mapped_length
  variable. Now, if mi_dynmap_file() is invoked with a size
  with an extra 7-byte margin (MEMMAP_EXTRA_MARGIN),
  the margin will eventually also get stored in mapped_length.
  So, un-mapping function can simply use the value stored in
  mapped_length in order to unmap the previously mapped
  region.

              BIN LOG HAS BEEN MOVED 

When moving the binary/relay log files from one location to
another and restarting the server with a different log-bin or
relay-log paths, would cause the startup process to abort. The
root cause was that the server would not be able to find the log
files because it would consider old paths for entries in the
index file instead of the new location.  What's even worse, the
relative paths would not be considered relative to the path
provided in log-bin and relay-log, but to mysql_data_dir.
      
We fix the cases where the server contains relative paths. When
the server is reading from the index file, it checks whether the
entry contains relative paths. If it does, we replace it with the
absolute path set in log-bin/relay-log option. Absolute paths
remain unchanged and the index must be manually edited to
consider the new log-bin and/or relay-log path (this should be
documented). This is a fix for a GA version, that does not break
behavior (that much).
      
For development versions, we should go with Zhenxing's approach 
that removes paths altogether from index files.

mysql-test/include/begin_include_file.inc:
  Added parameter to keep the begin_include_file.inc silent. Useful when 
  including scripts that contain platform dependent parameters, for example:
  
  --let $rpl_server_parameters=--log-bin=$tmpdir/slave-bin --relay-log=$tmpdir/slave-relay-bin
  --let $keep_include_silent=1
  source include/rpl_start_server.inc;
  --let $keep_include_silent=0
  
  We want the paths ($tmpdir/slave-bin and $tmpdir/slave-relay-bin) not to be in the 
  result file.
mysql-test/suite/rpl/t/rpl_binlog_index.test:
  Test case.
sql/log.cc:
  When finding the corresponding log entry in the index file, we first 
  normalize the paths before doing the comparison. This will make relative
  paths to be turned into absolute paths (based on the opt_bin_logname or
  opt_relay_logname) and then compared against also, expanded paths entered, 
  through CHANGE MASTER for instance.
sql/log.h:
  Added normalize_binlog_name, which turns relative paths, into absolute paths
  given the parameter: is_relay_log ? opt_relay_logname : opt_bin_logname .
sql/mysqld.cc:
  Exposing opt_bin_logname.
sql/mysqld.h:
  Exposing opt_bin_logname.

Automerged against latest mysql-5.5.

  
When passing an empty user to the connect function will cause
valgrind warnings. Seems that the client code is not prepared 
to handle empty users. On 5.6 this can even be triggered by 
START SLAVE PASSWORD='...'; i.e., without setting USER='...' on
the START SLAVE command (see WL#4143 for details on the new
additional START SLAVE commands).
  
To fix this, we disallow empty users when configuring the slave
connection parameters (this decision might be revisited if the 
client code accepts empty users in the future).

sql/slave.cc:
  We throw an error if an empty user is supplied to the connection 
  function.

                      AND HANG IN SHOW TABLE STATUS.

ISSUE: Table corruption due to concurrent queries.
       Different threads running insert and check
       query leads to table corruption. Not properly locked,
       rows are inserted in between check query.

SOLUTION: In check query mutex lock is acquired
          for a longer time to handle concurrent
          insert and check query.

NOTE: Additionally we backported the fix for CHECKSUM
      issue(bug#11758979).

innodb_change_buffering_debug prevents creating the Dup Key scenario on
windows

sporadically on 5.1. See Bug#12584161.

Test runs successfully on 5.5/trunk, so this changeset will
be null-merged.

Fix merge issues after discussing with Marko.

Remove btr_cur_t::ibuf_cnt. The only dependence on cursor->ibuf_cnt
was ibuf_set_entry_counter(). That code path was removed in the
original bug fix (marko.makela@oracle.com-20111107072802-dgwagejlpub0rjkd).

rb:819 approved by Jimmy Yang

A patch for alter_table-big.test has been committed earlier.
This is a patch for create-big.test:
The test used to time-out after 900 seconds. 
It relied on debug sleeps that are no longer present in the 
code. Since the sleeps are long gone, fixing the problem didn't 
involve just updating the result file or using macro 
"show_binlog_events2.inc" instead of "show binlog events" 
statement. The test needed to be rewritten using debug sync 
points, and result then needed to be updated.
So, the sleeps have been replaced by debug_sync points and the test execution time has 
been reduced significantly.

  Disable federated_plugin test for embedded, like other federated tests
  Also removed redundant include/not_embedded.inc from federated.test

Setting query_cache_size to larger values might fail depending on the memory 
pressure being put on the system. This can be seen on pushbuild as the test 
case query_cache_size_basic tries to allocate a +3GB query cache, which 
succeeds in some machines and fails in others.

So this part of the code where the test case tries to allocate +3GB query cache has been 
disabled for now to get the test running on pb2.

rb://608 approved by Sunny Bains

  
rb://816
approved by: Marko Makela
  
The title is misleading. This bug was actually introduced by
bug 12635227 and was unearthed by a later optimization.
We need to free buf_page_t structs that we are allocating using
malloc() at shutdown.

I manually checked that all the conflicting InnoDB changes are in 5.5 already.
Two things I am not sure about - I commented them with XXX in this patch.
I will further check with the authors of the changesets whether these things
should be present or not.

Problem was that built-in client-side support for Windows Native Authentication (WNA) was included only in the client library, but not into the server code (which also uses some of the sources from the client library).

This is fixed by modyfying sql/CMakeLists.txt to include the client-side WNA plugin library and enable WNA related code by defining AUTHENTICATION_WIN macro.

Also, the logic of libmysql/CMakeLists.txt is simplified a bit.

Follow-up patch to fix valgrind warnings.

BY CACHING OR REDUCING CREATEEVENT CALLS".
 
5.5 versions of MySQL server performed worse than 5.1 versions 
under single-connection workload in autocommit mode on Windows XP.
 
Part of this slowdown can be attributed to overhead associated
with constant creation/destruction of MDL_lock objects in the MDL
subsystem. The problem is that creation/destruction of these
objects causes creation and destruction of associated
synchronization primitives, which are expensive on Windows XP.
 
This patch tries to alleviate this problem by introducing a cache
of unused MDL_object_lock objects. Instead of destroying such
objects we put them into the cache and then reuse with a new
key when creation of a new object is requested.

To limit the size of this cache, a new --metadata-locks-cache-size
start-up parameter was introduced.

mysql-test/r/mysqld--help-notwin.result:
  Updated test after adding --metadata-locks-cache-size
  parameter.
mysql-test/r/mysqld--help-win.result:
  Updated test after adding --metadata-locks-cache-size
  parameter.
mysql-test/suite/sys_vars/r/metadata_locks_cache_size_basic.result:
  Added test coverage for newly introduced --metadata_locks_cache_size
  start-up parameter and corresponding global read-only variable.
mysql-test/suite/sys_vars/t/metadata_locks_cache_size_basic-master.opt:
  Added test coverage for newly introduced --metadata_locks_cache_size
  start-up parameter and corresponding global read-only variable.
mysql-test/suite/sys_vars/t/metadata_locks_cache_size_basic.test:
  Added test coverage for newly introduced --metadata_locks_cache_size
  start-up parameter and corresponding global read-only variable.
sql/mdl.cc:
  Introduced caching of unused MDL_object_lock objects, in order to
  avoid costs associated with constant creation and destruction of
  such objects in single-connection workloads run in autocommit mode.
  Such costs can be pretty high on systems where creation and 
  destruction of synchronization primitives require a system call 
  (e.g. Windows XP).
   
  To implement this cache,a list of unused MDL_object_lock instances 
  was added to MDL_map object. Instead of being destroyed 
  MDL_object_lock instances are put into this list and re-used later 
  when creation of a new instance is required. Also added 
  MDL_lock::m_version counter to allow threads having outstanding 
  references to an MDL_object_lock instance to notice that it has 
  been moved to the unused objects list.
   
  Added a global variable for a start-up parameter that limits
  the size of the unused objects list.
   
  Note that we don't cache MDL_scoped_lock objects since they
  are supposed to be created only during execution of DDL 
  statements and therefore should not affect performance much.
sql/mdl.h:
  Added a global variable for start-up parameter that limits the
  size of the unused MDL_object_lock objects list and constant
  for its default value.
sql/sql_plist.h:
  Added I_P_List<>::pop_front() function.
sql/sys_vars.cc:
  Introduced --metadata-locks-cache-size start-up parameter
  for specifying size of the cache of unused MDL_object_lock
  objects.

Follow up to fix freebsd compile issue.

Automerged approved bzr bundle in latest mysql-5.5.

                    OPTION SKIP-WRITE-BINLOG

System tables were not getting upgraded when
mysql_upgrade was run with --skip-write-binlog
option. (Same for --write-binlog.) Also, with
this option, mysql_upgrade_info file was not
getting created after the upgrade.

mysql_upgrade makes use of mysql client tool in
order to run upgrade scripts, while doing so it
passes some of the command line options (used to
start mysql_upgrade) directly to mysql client.
The reason behind this bug being, some options
like skip-write-binlog and upgrade-system-tables
were being passed to mysql tool along with other
options, and hence mysql execution failed due
presence of these invalid options.

Fixed this issue by filtering out the above mentioned
options from the list of options that will be passed to
mysql and mysqlcheck tools. However, since --write-binlog
is supported by mysqlcheck, this option would be used
explicitly while running mysqlcheck. (not part of patch,
already there)

Checking the contents of general log after the upgrade
is not doable via an mtr test. So performed manual test.
Added a test to verify the creation of mysql_upgrade_info.


client/mysql_upgrade.c:
  Bug#11827359 60223: MYSQL_UPGRADE PROBLEM WITH
                      OPTION SKIP-WRITE-BINLOG
  
  With this patch, --upgrade-system-tables and
  --write-binlog options will not be added to the
  list of options, used to start mysql and mysqlcheck
  tools.
mysql-test/r/mysql_upgrade.result:
  Added a testcase for Bug#11827359.
mysql-test/t/mysql_upgrade.test:
  Added a testcase for Bug#11827359.

my_double_round(DBL_MAX, -12, ....)
should return 'inf' rather than DBL_MAX

The problem is that floor(value/tmp) * tmp
is inlined, and optimized away.

The solution seems to be to prevent inlining by pre-computing value/tmp and
storing it in a variable.

No new test case: main.type_float fails without this patch.