Copy any data (currently table name and table index) that may be
destroyed after releasing the kernel mutex into internal cache's
storage.

This is done in efficient manner using ha_storage type and a given
string is copied only once into the cache's storage. Later additions of
the same string use the already stored string, thus allocating memory
only once per unique string.

Approved by:	Marko

Add a type that stores chunks of data in its own storage and avoids
duplicates. Supported methods:

ha_storage_create()
Allocates new storage object.

ha_storage_put()
Copies a given data chunk into the storage and returns pointer to the
copy. If the data chunk is already present, a pointer to the existing
object is returned and the given data chunk is not copied.

ha_storage_empty()
Clears (empties) the storage from all data chunks that are stored in it.

ha_storage_free()
Destroys a storage object. Opposite to ha_storage_create().

Approved by:	Marko

rec_get_n_fields(), rec_offs_validate(), and rec_offs_make_valid().

This was inadvertently reduced to 16384 bytes in r1861.  For testing,
this can be set as low as UNIV_PAGE_SIZE.

row_merge(): Add the assertion ut_ad(half > 0).

row_merge_sort(): Compute the half of the merge file correctly.  The
previous implementation used truncating division, which may result in
loss of records when the file size in blocks is not a power of 2.

Non-functional: put the code that clears the IS cache into a separate
function.

Cosmetic: initialize the members of the cache in the same order as
they are defined in the structure.

Make comment more clear (hopefully).

Use the newly introduced mem_alloc2() to use the memory that has been
allocated in addition to the requested memory. This is done in order to
avoid wasting memory.

Do not calculate the sizes and offsets of the chunks in advance in
table_cache_init() because it is unknown how much bytes will actually
be allocated by mem_alloc2(). Rather calculate these on the run: after
each chunk is allocated set its size and the offset of the next chunk.

Similar patch approved by:	Marko

merge buffer, write the next record to the beginning of the emptied buffer.
This fixes one of the bugs mentioned in r1872.

Some bug still remains, because innodb-index.test will lose some
records from the clustered index after add primary key (a,b(255),c(255))
when row_merge_block_t is reduced to 8192 bytes.

row_merge(): Add the parameter "half".  Add some Valgrind instrumentation.
Note that either stream can end before the other one.

row_merge_sort(): Calculate "half" for row_merge().

mem_alloc2(): New macro.  This is a variant of mem_alloc() that
returns the allocated size, which is equal to or greater than
the requested size.

mem_alloc_func(): Add the output parameter *size for the allocated size.
When it is set, adjust the parameter passed to mem_heap_alloc().

rec_copy_prefix_to_buf_old(), rec_copy_prefix_to_buf(): Use mem_alloc2()
instead of mem_alloc().

row_merge_print_read and row_merge_print_write.

was actually obtained from the buddy allocator.  This should avoid some
internal memory fragmentation in mem_heap_create() and mem_heap_alloc().

mem_area_alloc(): Change the in parameter size to an in/out parameter.
Adjust the size based on what was obtained from pool->free_list[].

mem_heap_create_block(): Adjust block->len to what was obtained from
mem_area_alloc().

column d to two SELECT FROM t1.

rec_print_comp(): New function, sliced from rec_print_new().

rec_print_old(), rec_print_comp(): Print the untruncated length of the column.

row_merge_print_read, row_merge_print_write, row_merge_print_cmp:
New flags, to enable debug printout in UNIV_DEBUG builds.

row_merge_tuple_print(): New function for UNIV_DEBUG builds.

row_merge_read_rec(): Obey row_merge_print_read.

row_merge_buf_write(), row_merge_write_rec_low(),
row_merge_write_eof(): Obey row_merge_print_write.

row_merge_cmp(): Obey row_merge_print_cmp.

in fast index creation.

row_merge_write_eof(), row_merge_buf_write(): When UNIV_DEBUG_VALGRIND
is defined, fill the rest of the block (after the end-of-block marker)
with 0xff.

innodb_lock_waits. See
https://svn.innodb.com/innobase/InformationSchema/TransactionsAndLocks
for design notes.

Things that need to be resolved before this goes live:
* MySQL must add thd_get_thread_id() function to their code
  http://bugs.mysql.com/30930
* Allocate memory from mem_heap instead of using mem_alloc()
* Copy table name and index name into the cache because they may be
  freed later which will result in referencing freed memory

Approved by:	Marko

of fast index creation.

row_merge_read_rec(): Correct a typo in a comment.  Fix error in
arithmetics when the record spans two blocks.

row_merge_write_rec_low(): Add a "size" parameter.  Add debug assertions
about extra_size and size.

row_merge_write_rec(): After writing a record, properly advance the
buffer pointer.

all columns present in offsets.  Add a const qualifier to the
dict_index_t* parameter.

Add const qualifiers.

that row_merge_blocks() will have some work to do when
row_merge_block_t is shrunk to 8192 bytes.

Currently, this will cause a debug assertion failure, because
row_merge_cmp() is considering all columns, not just the unique ones.

Correctly handle node pointer records containing variable-length columns
with two-byte length.

column prefixes in clustered indexes.

innodb-index.test: Add test cases for creating primary keys
containing column prefixes.

row_ext_lookup().

via my_error().  Add a test case to innodb-index.test.

the 65,535-byte VARCHAR length limit of MySQL.

(smart ALTER TABLE) from ha_innodb.cc to a separate module, handler0alter.cc.

been removed in r1808.

#ifdef UNIV_DEBUG.  This should have been done in r1014.

data dictionary object new_table.  This fixes a memory leak.

existed before the fast-index-creation code was merged, in r1414.

Do not call row_prebuilt_table_obsolete(innodb_table) until after
the table has been renamed to a temporary name.  Otherwise, the
following could happen when creating a clustered index on table T:

(a1) copy T to T#1
(a2) mark T obsolete
(b1) add the name of T to the background drop list
(a3) rename T to T#2 and T#1 to T
(b2) drop the table on the background

These steps are executed by two threads, a and b.

If b1 is executed after a3, all is fine: the name T#2 will be added
to the background drop list.  If b1 is executed before a3, the name
T will be added, and T#2 will survive.

row_add_table_to_background_drop_list(): Replace the dict_table_t*
parameter with const char* (the table name).

row_check_table_for_mysql(): Replace prebuilt->table with table.

These should have gone to branches/fts.

Spotted by: Marko and Ken

These should have gone in branches/fts

Spotted by: Marko and Ken

Reviewed by: Heikki

Use UNIV_MEM_ASSERT_W() instead of UNIV_MEM_ASSERT_RW().
The memory area need not be initialized.
This mistake was made in r1815.