- WL#3240 "log DROP TABLE in Maria"
- similarly, log RENAME TABLE, REPAIR/OPTIMIZE TABLE, and
DELETE no_WHERE_clause (== the DELETE which just truncates the files)
- create_rename_lsn added to MARIA_SHARE's state
- all these operations (except DROP TABLE) also update the table's
create_rename_lsn, which is needed for the correctness of
Recovery (see function comment of _ma_repair_write_log_record()
in ma_check.c)
- write a COMMIT record when transaction commits.
- don't log REDOs/UNDOs if this is an internal temporary table
like inside ALTER TABLE (I expect this to be a big win). There was
already no logging for user-created "CREATE TEMPORARY" tables.
- don't fsync files/directories if the table is not transactional
- in translog_write_record(), autogenerate a 2-byte-id for the table
and log the "id->name" pair (LOGREC_FILE_ID); log
LOGREC_LONG_TRANSACTION_ID; automatically store
the table's 2-byte-id in any log record.
- preparations for Checkpoint: translog_get_horizon(); pausing Checkpoint
when some dirty pages are unknown; capturing trn->rec_lsn,
trn->first_undo_lsn for Checkpoint and log's low-water-mark computing.
- assertions, comments.


storage/maria/Makefile.am:
  more files to build
storage/maria/ha_maria.cc:
  - logging a REPAIR log record if REPAIR/OPTIMIZE was successful.
  - ha_maria::data_file_type does not have to be set in every info()
  call, just do it once in open().
  - if caller said that transactionality can be disabled (like if
  caller is ALTER TABLE) i.e. thd->transaction.on==FALSE, then we
  temporarily disable transactionality of the table in external_lock();
  that will ensure that no REDOs/UNDOs are logged for this possibly
  massive write operation (they are not needed, as if any write fails,
  the table will be dropped). We re-enable in external_lock(F_UNLCK),
  which in ALTER TABLE happens before the tmp table replaces the original
  one (which is good, as thus the final table will have a REDO RENAME
  and a correct create_rename_lsn).
  - when we commit we also have to write a log record, so
  trnman_commit_trn() calls become ma_commit() calls
  - at end of engine's initialization, we are potentially entering a
  multi-threaded dangerous world (clients are going to be accepted)
  and so some assertions of mutex-owning become enforceable, for that
  we set maria_multi_threaded=TRUE (see ma_control_file.c)
storage/maria/ha_maria.h:
  new member ha_maria::save_transactional (see also ha_maria.cc)
storage/maria/ma_blockrec.c:
  - fixing comments according to discussion with Monty
  - if a table is transactional but temporarily non-transactional
  (like in ALTER TABLE), we need to give a sensible LSN to the pages
  (and, if we give 0, pagecache asserts).
  - translog_write_record() now takes care of storing the share's
  2-byte-id in the log record
storage/maria/ma_blockrec.h:
  fixing comment according to discussion with Monty
storage/maria/ma_check.c:
  When REPAIR/OPTIMIZE modify the data/index file, if this is a
  transactional table, they must sync it; if they remove files or rename
  files, they must sync the directory, so that everything is durable.
  This is just applying to REPAIR/OPTIMIZE the logic already implemented
  in CREATE/DROP/RENAME a few months ago.
  Adding a function to write a LOGREC_REPAIR_TABLE at end of
  REPAIR/OPTIMIZE (called only by ha_maria, not by maria_chk), and
  to update the table's create_rename_lsn.
storage/maria/ma_close.c:
  fix for a future bug
storage/maria/ma_control_file.c:
  ensuring that if Maria is running in multi-threaded mode, anybody
  wanting to write to the control file and update
  last_checkpoint_lsn/last_logno owns the log's lock.
storage/maria/ma_control_file.h:
  see ma_control_file.c
storage/maria/ma_create.c:
  when creating a table:
  - sync it and its directory only if this is a transactional table
  and there is a log (no point in syncing in maria_chk)
  - decouple the two uses of linkname/linkname_ptr (for index file and
  for data file) into more variables, as we need to know all links
  until the moment we write the LOGREC_CREATE_TABLE.
  - set share.data_file_type early so that _ma_initialize_data_file()
  knows it (Monty's bugfix so that a table always has at least a bitmap
  page when it is created; so data-file is not 0 bytes anymore).
  - log a LOGREC_CREATE_TABLE; it contains the bytes which we have
  just written to the index file's header. Update table's
  create_rename_lsn.
  - syncing of kfile had been bugified in a previous merge, correcting
  - syncing of dfile is now needed as it's not empty anymore
  - in _ma_initialize_data_file(), use share's block_size and not the
  global one. This is a gratuitous change, both variables are equal,
  just that I find it more future-proof to use share-bound variable
  rather than global one.
storage/maria/ma_delete_all.c:
  log a LOGREC_DELETE_ALL record when doing ma_delete_all_rows();
  update create_rename_lsn then.
storage/maria/ma_delete_table.c:
  - logging LOGREC_DROP_TABLE; knowing if this is needed, requires
  knowing if the table is transactional, which requires opening the
  table.
  - we need to sync directories only if the table is transactional
storage/maria/ma_extra.c:
  questions
storage/maria/ma_init.c:
  when maria_end() is called, engine is not multithreaded
storage/maria/ma_loghandler.c:
  - translog_inited has to be visible to ma_create() (see how it is used
  in ma_create())
  - checkpoint record will be a single record, not three
  - no REDO for TRUNCATE (TRUNCATE calls ma_create() internally so will
  log a REDO_CREATE)
  - adding REDO for DELETE no_WHERE_clause (fast DELETE of all rows by
  truncating the files), REPAIR.
  - MY_WAIT_IF_FULL to wait&retry if a log write hits a full disk
  - in translog_write_record(), if MARIA_SHARE does not yet have a
  2-byte-id, generate one for it and log LOGREC_FILE_ID; automatically
  store this short id into log records.
  - in translog_write_record(), if transaction has not logged its
  long trid, log LOGREC_LONG_TRANSACTION_ID.
  - For Checkpoint, we need to know the current end-of-log: adding
  translog_get_horizon().
  - For Control File, adding an assertion that the thread owns the
  log's lock (control file is protected by this lock)
storage/maria/ma_loghandler.h:
  Changes in log records (see ma_loghandler.c).
  new prototypes, new functions.
storage/maria/ma_loghandler_lsn.h:
  adding a type LSN_WITH_FLAGS especially for TRN::first_undo_lsn,
  where the most significant byte is used for flags.
storage/maria/ma_open.c:
  storing the create_rename_lsn in the index file's header (in the
  state, precisely) and retrieving it from there.
storage/maria/ma_pagecache.c:
  - my set_if_bigger was wrong, correcting it
  - if the first_in_switch list is not empty, it means that
  changed_blocks misses some dirty pages, so Checkpoint cannot run and
  needs to wait. A variable missing_blocks_in_changed_list is added to
  tell that (should it be named missing_blocks_in_changed_blocks?)
  - pagecache_collect_changed_blocks_with_lsn() now also tells the
  minimum rec_lsn (needed for low-water mark computation).
storage/maria/ma_pagecache.h:
  see ma_pagecache.c
storage/maria/ma_panic.c:
  comment
storage/maria/ma_range.c:
  comment
storage/maria/ma_rename.c:
  - logging LOGREC_RENAME_TABLE; knowing if this is needed, requires
  knowing if the table is transactional, which requires opening the
  table.
  - update create_rename_lsn
  - we need to sync directories only if the table is transactional
storage/maria/ma_static.c:
  comment
storage/maria/ma_test_all.sh:
  - tip for Valgrind-ing ma_test_all
  - do "export maria_path=somepath" before calling ma_test_all,
  if you want to run ma_test_all out of storage/maria (useful
  to have parallel runs, like one normal and one Valgrind, they
  must not use the same tables so need to run in different directories)
storage/maria/maria_def.h:
  - state now contains, in memory and on disk, the create_rename_lsn
  - share now contains a 2-byte-id
storage/maria/trnman.c:
  preparations for Checkpoint: capture trn->rec_lsn, trn->first_undo_lsn;
  minimum first_undo_lsn needed to know log's low-water-mark
storage/maria/trnman.h:
  using most significant byte of first_undo_lsn to hold miscellaneous
  flags, for now TRANSACTION_LOGGED_LONG_ID.
  dummy_transaction_object is already declared in ma_static.c.
storage/maria/trnman_public.h:
  dummy_transaction_object was declared in all files including
  trnman_public.h, while in fact it's a single object.
  new prototype
storage/maria/unittest/ma_test_loghandler-t.c:
  update for new prototype
storage/maria/unittest/ma_test_loghandler_multigroup-t.c:
  update for new prototype
storage/maria/unittest/ma_test_loghandler_multithread-t.c:
  update for new prototype
storage/maria/unittest/ma_test_loghandler_pagecache-t.c:
  update for new prototype
storage/maria/ma_commit.c:
  function which wraps:
  - writing a LOGREC_COMMIT record (==commit on disk)
  - calling trnman_commit_trn() (=commit in memory)
storage/maria/ma_commit.h:
  new header file
.tree-is-private:
  this file is now needed to keep our tree private (don't push it
  to public trees). When 5.1 is merged into mysql-maria, we can abandon
  our maria-specific post-commit trigger; .tree_is_private will take
  care of keeping commit mails private. Don't push this file to public
  trees.