rec_get_offsets_reverse(): Calculate extra_size correctly.

page_zip_apply_log(): Fix an off-by-one error in comparison.
Replace heap_status with hs where possible.
Increment the heap_no in heap_status correctly.

page_zip_decompress(): Eliminate the local variable "err".
Check for Z_STREAM_END only at the start of a record, so that
incomplete records will always be detected.

page_zip_write_rec(): Calculate the address of "storage" in the
same way as elsewhere.  Add TODO comments regarding the handling
of the uncompressed fields (BLOB pointers, trx_id, and roll_ptr).

btr_create(): page_zip_compress() returns FALSE on failure.

page_zip_write_header(): Write to page_zip->data[] instead of page_zip[].

buf_flush_init_for_writing(): Add parameter page_zip and set the fields
also in the header of the compressed page.

btr_cur_search_to_nth_level(): Add ut_ad() on page_zip_validate().

page_zip_compress(), page_zip_decompress(), page_zip_write_rec():
Note that the end marker of the modification log is 1 byte.

page_zip_find_heap_no(): Remove.

page_zip_apply_log(): Remove parameter "page".  Instead of a 2-byte offset
to the record, decode the heap number using a variable-length code.

page_zip_write_rec(): Check the range of heap_no with debug assertions.
Encode the heap number instead of an offset to the start of the record.

to page0zip.c.

function prototypes and comments.  These changes were accidentally
forgotten from revision 253.

operation succeeds.

page_zip_dir_set(): Remove, as the slots will be written to a temporary
buffer.

page_zip_dir_encode(): Replace page_zip with buf.  Make some assertions
more accurate.  Write the dense page directory to buf.

page_zip_compress(): Allocate a temporary buffer for the compressed page
except the page header.  Make some assertions more accurate.

page_zip_compress(), page_zip_decompress(): Remove 2 bytes of empty space
adjacent to the area reserved for storing uncompressed columns.

page_zip_decompress(): Free index and heap at the end of the function.
Do not write the index to the MLOG_ZIP_DECOMPRESS record, since it can be
decoded from the compressed page.

now that deletion of records on compressed pages is guaranteed to succeed.

on a compressed page.

page_zip_get_n_relocated(), page_zip_set_n_relocated(),
page_zip_get_relocated(): Remove.

page0zip.c, page0zip.ic: Remove all references to n_relocated.

page_cur_insert_rec_low(): On pages that are compressed,
never relocate records that are allocated from the free list.

page_zip_compress(): Add assertions !c_stream.avail_in where appropriate.
Add assertions on c_stream.next_in.  Correct malformed assertion on
externs > c_stream.next_in.  Note that there may be trailing garbage after
the last record.

page_zip_fields_decode(): Correctly decode variable-length fields having
maximum length greater than 255 bytes.

page_zip_decompress(): Remove the special treatment of the case !n_dense.
Replace the Z_NO_FLUSH argument of inflate() with Z_SYNC_FLUSH.
Treat Z_OK return value the same as Z_BUF_ERROR: always check avail_out.
After decompressing all records, decompress any trailing garbage.

page_cur_insert_rec_low(): Note that the relocation log
on the compressed page needs to reflect some changes of extra_size.

do not allow extra_size to decrease on compressed pages.

Split page_mem_alloc() to page_mem_alloc_free() and page_mem_alloc_heap().

page_cur_insert_rec_low(): Remove parameter "tuple".  Implement some of the
logic from page_mem_alloc().

page_cur_tuple_insert(): Convert the tuple to a record and calculate offsets.

page_zip_validate(): Assert that the page is in compact format.

Remove the declaration of the undefined function
page_zip_available_noninline().

Make page_zip_available() private to page0zip.c and page0zip.ic.

compressed pages.

btr_root_raise_and_insert(): Distinguish root_page_zip and new_page_zip.

btr_cur_set_ownership_of_extern_field(): Do not log the write on the
uncompressed page if it will be logged for page_zip.

lock_rec_insert_check_and_lock(), lock_sec_rec_modify_check_and_lock():
Update the max_trx_id field also on the compressed page.

mlog_write_ulint(): Add UNIV_UNLIKELY hints.  Remove trailing white space.

mlog_log_string(): Remove trailing white space.

rec_set_field_extern_bits(): Remove parameter mtr, as the write will either
occur in the heap, or it will be logged at a higher level.

recv_parse_or_apply_log_rec_body(),
page_zip_write_header(): Add log record type MLOG_ZIP_WRITE_HEADER.

page_header_set_field(): Pass mtr=NULL to page_zip_write_header().

page_header_reset_last_insert(): Pass mtr to page_zip_write_header().

btr_page_set_index_id(), btr_page_set_level(),
btr_page_set_next(), btr_page_set_prev(): Pass mtr to page_zip_write_header().

row_upd_rec_sys_fields(): Pass mtr=NULL to page_zip_write_trx_id() and
page_zip_write_roll_ptr(), since the write will be logged at a higher level.

page_zip_write_header(): Add parameter mtr.
page_zip_write_header_log(): New function.

Remove rec_set_nth_field_extern_bit().
Make rec_set_nth_field_extern_bit_old() static.
Rename rec_set_nth_field_extern_bit_new()
to rec_set_field_extern_bits_new() and make it static.

row_ins_index_entry_low(): Remove bogus TODO comment.

dict_mem_table_create(): Initialize table->zip.

btr0cur.c: Distinguish compressed BLOBs based on page_zip or table->zip.

Fix the way how btr_free_externally_stored_field() is called in purge.

btr_free_externally_stored_field(): Add parameter field_ref that points
directly to the BLOB reference.  Use rec, offsets, page_zip, and i
only for the page_zip_write_blob_ptr() call.

row_purge_upd_exist_or_extern(): Do not assume that the undo log contains
the entire record.  Only pass the BLOB reference to
btr_free_externally_stored_field().

btr_cur_pessimistic_insert(): Pass the "extern storage" flags to
btr_root_raise_and_insert() or btr_page_split_and_insert().

btr_copy_externally_stored_field(): Include local_len in the returned length.

btr_cur_optimistic_insert(): Replace page_cur_insert_rec_low()
with page_cur_tuple_insert().

btr_cur_pessimistic_update(): Add the columns of big_rec_vec to ext_vect,
so that the "extern storage" bits will be set correctly in
btr_cur_insert_if_possible().

This has not been extensively tested yet, because some other part of the
code breaks in "ibtestblob".

btr_free_page_low(): Add parameters "space" and "page_no", because they
are omitted from compressed BLOB pages.

btr0cur.c: Implement the compression and decompression of BLOB columns,
enabled at compile-time (#define ZIP_BLOB TRUE) for now.

btr_rec_free_externally_stored_fields(),
btr_copy_externally_stored_field(): Made static

mlog_log_string(): New function, split from mlog_write_string(), allows
to avoid a dummy memcpy() of compressed BLOB pages.

flag of records.  The flags may only be updated in heap-allocated
copies of records.

btr_root_raise_and_insert(),
btr_page_split_and_insert(),
btr_cur_insert_if_possible(),
btr_cur_optimistic_insert(),
btr_cur_pessimistic_insert(),
page_cur_tuple_insert(),
page_cur_insert_rec_low(): Add parameters "ext" and "n_ext".

dtuple_convert_big_rec(): Make parameter "ext" const.

BLOB pointers, trx_id, and roll_ptr.

btr_empty(), btr_create(), page_create(): Add parameter "index", as some
index information will be encoded on the compressed page.

Define REC_NODE_PTR_SIZE as 4.

Allow btr_page_reorganize() and btr_page_reorganize_low() to fail.

Define the error code DB_ZIP_OVERFLOW.

Make row_ins_index_entry_low() static.

page0zip: Encode the index, log reorganized records, and store uncompressed
fields separately from the compressed data stream.

that will require complete index information.

dict_create_index_step(): invoke dict_index_add_to_cache() before btr_create()

dict_index_remove_from_cache(): make public

dict_index_get_if_in_cache_low(): new function, for holding dict_sys->mutex

buf_flush_init_for_writing(): remove the temporary hook to page_zip_compress()

page_create(): add temporary hook to page_zip_compress()

buf_flush_init_for_writing(): The reported dense page directory size was
4 bytes too much.  Subtract 2 (infimum and supremum) from n_heap.

page_zip_decompress(): When decompressing the last user record, only set
heap_no and the status bits if there is data to decode, i.e., there
are user records on the page.

buf_flush_init_for_writing(): Improve the diagnostics and make the
condition for skipping pages accurate.

univ.i: Introduce UNIV_ZIP_DEBUG for enabling some page_zip_validate() tests.

page0zip.h, page0zip.c: Define and use page_zip_validate() in
page_zip_compress() and page_zip_write() if UNIV_ZIP_DEBUG or UNIV_DEBUG
is defined.

Before the speedc test was interrupted, 121,765 B-tree pages were written.

buf_flush_init_for_writing(): Do not compress other than B-tree pages
outside the system tablespace.  Report non-B-tree pages.

page_zip_decompress(): Clear the unused heap space on the uncompressed page,
so that the whole buffer for the uncompressed page will be initialized and
page_zip_validate() will always succeed.

page_zip_dir_decode(): Correct the handling of the free list.

page_zip_set_extra_bytes(): Remove off-by-one error in the first loop.

page_zip_apply_log(): Replace parameter end with size, and let end=data+size.

page_zip_decompress(): Properly handle pages where the first user record has
more than REC_N_NEW_EXTRA_BYTES extra bytes.

page_delete_rec_list_end(): Remove page_zip_temp.  This operation will be
done completely in-place on page_zip.  If page_zip is specified, clear the
data bytes and the info and status bits of deleted records and clear the
removed directory slots.

page_dir_delete_slot(): Clear the last directory slot, which will be removed.

decompresses properly.

page_mem_free(): Adjust the temporary condition for zeroing data.

page_zip_compress(): Do not accept Z_STREAM_END from non-final deflate().
Tighten the assertion on c_stream.avail_in.

page_zip_dir_sort(): Note that the high bound is not inclusive.

page_zip_dir_decode(): Remove off-by-one error in page_zip_dir_sort() call.

page_zip_set_extra_bytes(): Add the termination condition that was forgotten
from the second for loop.  Simplify the code a little.

page_zip_decompress(): Do not accept Z_STREAM_END from non-final inflate().
Tighten the assertion on d_stream.avail_out.  Increment heap_status correctly.

A page with multiple records or deleted records still does not compress
or decompress properly.

buf_flush_init_for_writing(): Initialize block->page_zip properly so that all
assertions in page0zip can be enabled.

page_zip_decompress(): Note that corrupt data should not lead to assertions.

page_zip_dir_set(): Correct the interface.  Fix off-by-one error.
page_zip_dir_get(): Fix off-by-one error.

page0zip.c: Replace n_heap with n_dense and add comments about
the infimum and supremum records whenever we subtract 2 from heap_no.
Fix some programming errors.

buf0flu.c: Allocate the temporary buffer from buf_frame_alloc().

page_zip_simple_validate(): Do not assert page_zip->m_start >= PAGE_DATA.

page_zip_compress(): Replace some assertions with page_zip_simple_validate(),
and do not assert anything about page_zip->data contents.

page_zip_validate(): Do not compare the page trailer bytes.

page_zip_write(): Assert that the entire page headers match and
that page_zip->m_start >= PAGE_DATA.

Add a hook to buf0flu.c for testing compression and decompression.
TODO: adapt page_zip_write() calls.