that was found while investigating Bug #19081.

with page_zip_available() in order to avoid an extra page_zip_compress().

page_zip_available(): Make the function public.

page0zip.ic: Sort the inline function declarations in order to avoid
forward references, which do not work on some compilers.

The function will be invoked in page_zip_decompress() before setting
page_zip->m_start or page_zip->m_end.

on B-tree index pages.

page_rec_set_next(): Assert that rec != next.

rec_get_next_ptr(), rec_get_next_offs(): On compact pages, assert that
there are at least REC_N_NEW_EXTRA_BYTES + 1 between records.

page_cur_insert_rec_write_log(): Replace a buf_frame_align() call
with ut_align_offset().

page_cur_insert_rec_low(): Assert that current_rec != insert_rec.

page_zip_reorganize() was invoked.

btr_compress(): Obtain orig_pred and orig_succ after copying the records.
Add a debug assertion about FIL_PAGE_PREV.

page_copy_rec_list_end(), page_copy_rec_list_start(): Change the return
type from ibool to rec_t.  Adjust the return value after invoking
page_zip_reorganize().

uncompressed storage, to avoid bogus warnings about page number mismatch.

Replace most occurrences of #if defined UNIV_DEBUG || defined UNIV_ZIP_DEBUG
with #ifdef UNIV_ZIP_DEBUG.

disable unless #ifdef UNIV_LOG_ARCHIVE.

btr_compress(): Invoke page_zip_validate() on the page being compressed.

recv_parse_or_apply_log_rec_body(): Assert that MLOG_WRITE_STRING is
never used on compressed B-tree pages.

fil_read(), fil_write(): Make these inlined functions in fil0fil.c.

fil_write_lsn_and_arch_no_to_file(): Remove the parameter space_id and
note that this function is to be called on the system tablespace, which
is uncompressed.

recv_parse_or_apply_log_rec_body(): Assert that mlog_parse_nbytes() is
never called on compressed B-tree pages.

page_zip_simple_validate(): Correct a typo in a debug assertion.

xdes_calc_descriptor_page(): Fix an incorrect debug assertion.

and obey the added flag page_zip_validate_header_only.

page_zip instead of calling fil_space_get_zip_size().  In
fil_create_new_single_table_tablespace(), the table space has not yet
been created.  Handle also FIL_PAGE_TYPE_ALLOCATED.

fil_node_open_file(): Set node->size correctly for compressed tablespaces.

fsp_header_write_space_id(): Rename to fsp_header_write_fields(),
add parameter zip_size.

fil_io(): Add UNIV_UNLIKELY hints to assertion-like tests.

one megabyte at a time, no matter what the compressed page size is.

page_zip_assertion() failure in page_copy_rec_list_end().

btr_root_raise_and_insert(), btr_lift_page_up(), btr_compress():
Add page_zip_validate() assertions.

btr_compress(): Only copy FIL_PAGE_PREV when UNIV_BTR_DEBUG is defined.

page_cur_delete_rec(): Document why the page_zip_validate() assertion
was removed.

page_copy_rec_list_end(): Remove the page_zip_validate() assertion and
document why.

page_move_rec_list_end(): Add page_zip_validate() assertion.

page_cur_delete_rec(): Do not call page_zip_validate() in the beginning,
because btr_set_min_rec_mark() in btr_cur_pessimistic_delete() will
cause a temporary mismatch.

Document temporary mismatches caused by btr_set_min_rec_mark() calls
and explain why they will not cause any problems.

ut_is_2pow(): New function for testing if a number is zero or a power of two.
Use this function instead of bitwise arithmetics or ut_2_power_up() where
possible.

ut_a(page_zip_validate()) that are enabled if UNIV_DEBUG or
UNIV_ZIP_DEBUG is defined.

mlog_parse_string(): Remove an off-by-one error in an assertion.

fil_extend_space_to_desired_size(): fsp_header_get_free_limit(),
fsp_try_extend_data_file(): Replace UNIV_PAGE_SIZE with the actual page size.

PAGE_ZIP_MIN_SIZE: New constant, to be used in assertions.

FSP_SEG_INODES_PER_PAGE: Add parameter zip_size.

fsp_seg_inode_page_get_nth_inode(), fsp_seg_inode_page_find_used(),
fsp_seg_inode_page_find_free(): Add parameter zip_size.

ibuf_parse_bitmap_init(), ibuf_bitmap_page_init(),
ibuf_bitmap_page_get_bits(), ibuf_bitmap_set_bits(),
ibuf_bitmap_page_no_calc(), ibuf_bitmap_get_map_page(),
xdes_calc_descriptor_page(), xdes_calc_descriptor_index(),
fsp_descr_page(): Add parameter zip_size.

pages occur every zip_size pages in compressed tablespaces, instead of
UNIV_PAGESIZE (or XDES_DESCRIBED_PER_PAGE).

ibuf_bitmap_page(): Add parameter zip_size.

ibuf_fixed_addr_page(): Add parameter space.

os_aio_simulated_handle(): Temporarily disable os_file_check_page_trailers(),
which cannot be invoked on compressed pages.

dict_table_add_system_columns(): New function, split from
dict_table_add_to_cache().

mlog_parse_index(): Add system columns to the dummy table and identify
DB_TRX_ID and DB_ROLL_PTR in the dummy index.

buf_LRU_get_free_block(): Note that page_zip->data should be allocated from
an aligned memory pool.

buf_flush_buffered_writes(): Write compressed pages to disk.

buf_flush_post_to_doublewrite_buf(): Copy compressed pages to the
doublewrite buffer.  Zero fill any excess space.

buf_flush_init_for_writing(): Treat all compressed pages the same.

buf_read_page_low(): Read compressed pages from disk.

buf_page_io_complete(): Process compressed pages.

trx_sys_doublewrite_init_or_restore_page(): Process compressed pages.

mlog_write_initial_log_record_fast(): Enable a debug printout
#ifdef UNIV_LOG_DEBUG.

fsp_header_init(), fsp_fill_free_list(): Pass the compressed page size
to buf_page_create().

page_zip_compress_write_log(): Flatten the if-else if-else logic.

page_zip_parse_write_blob_ptr(): Do not test page_zip if page==NULL.

page_zip_parse_write_node_ptr(): Do not test page_zip if page==NULL.
Invoke mlog_close() correctly.

row_sel_store_row_id_to_prebuilt(): Add UNIV_UNLIKELY hint to an
assertion-like test.

pages.

buf_flush_post_to_doublewrite_buf(): Add a TODO comment about compressed pages.

mach_read_from_4(...) != mach_read_from_4(...) with memcmp(..., ..., 4).

a few places accordingly.

os_aio_simulated_handle(): Add TODO comments about skipping the write
checks for compressed pages.

dict_create_sys_tables_tuple(): Write the compressed page size to
the TYPE column.

open_or_create_data_files(): Simplify the fil_node_create() call.

fil_node_create(): Do not touch space->zip_size.  It was already initialized
by fil_space_create().

fil_reset_too_high_lsns(), buf_flush_buffered_writes(): Add TODO comment
about compressed pages.

buf_flush_init_for_writing(): Handle pages of type FIL_PAGE_INODE,
FIL_PAGE_IBUF_BITMAP, and FIL_PAGE_TYPE_FSP_HDR as uncompressed ones.

page_zip_compress_write_log(): Make static.

page_zip_compress(): Add optional parameter mtr for redo logging.

page_zip_reorganize(): Low-level counterpart of btr_page_reorganize().

page_zip_copy(): Add debug assertions about mtr_memo_contains.

page_cur_insert_rec_low(): Try page_zip_reorganize() and seek to the
new position of insert_rec if it succeeds.

page_copy_rec_list_end(), page_copy_rec_list_start():
Try page_zip_reorganize().

page_move_rec_list_end(): Remove bogus comment.

page_zip_copy(), page_zip_compress_write_log(): Add parameter 'index'.

page_zip_parse_write_header(): Check for !page_zip only if page != NULL.

page_zip_compress_write_log(), page_zip_parse_compress(): Omit some
fields in the page header.  Omit the unused bytes between the modification
log and the page trailer.

parse_or_apply_log_rec_body(): Remove a bogus debug assertion.

page_move_rec_list_start() and page_move_rec_list_end().  Relax the
conditions on insert_will_fit if page_zip is set.

page_delete_rec_list_start(): Make public.

page_zip_copy(): Clear REC_INFO_MIN_REC_FLAG if FIL_PAGE_PREV != FIL_NULL.

set the FIL_PAGE_PREV field of merge_page to FIL_NULL before copying the
records in order not to break the assumption of page_zip_compress() that
min_rec_mark is always set on the first user record of a non-leaf page
whose FIL_PAGE_PREV field is FIL_NULL, and never otherwise.

btr_compress(): Defer any tree modifications until the records
have successfully been copied.

row_purge_remove_sec_if_poss_low(): Simplify the setting of
the return status.

btr_lift_page_up(): If page_copy_rec_list_end() fails, resort to
page_zip_copy().

page_zip_copy(): Validate the copy of the page.