The low-level file system page header & trailer offsets. More...

#include "univ.i"

Classes
struct	Fil_page_header
	A wrapper class to help print and inspect the file page header. More...

Functions
std::ostream &	operator<< (std::ostream &out, const Fil_page_header &header) noexcept
	Overload the global output operator to handle an object of type Fil_page_header. More...

Variables
constexpr uint32_t	FIL_PAGE_SPACE_OR_CHKSUM = 0
	The byte offsets on a file page for various variables. More...

constexpr uint32_t	FIL_PAGE_OFFSET = 4
	page offset inside space More...

constexpr uint32_t	FIL_PAGE_PREV = 8
	if there is a 'natural' predecessor of the page, its offset. More...

constexpr uint32_t	FIL_PAGE_SRV_VERSION = 8
	On page 0 of the tablespace, this is the server version ID. More...

constexpr uint32_t	FIL_PAGE_NEXT = 12
	if there is a 'natural' successor of the page, its offset. More...

constexpr uint32_t	FIL_PAGE_SPACE_VERSION = 12
	On page 0 of the tablespace, this is the server version ID. More...

constexpr uint32_t	FIL_PAGE_LSN = 16
	lsn of the end of the newest modification log record to the page More...

constexpr uint32_t	FIL_PAGE_TYPE = 24
	file page type: FIL_PAGE_INDEX,..., 2 bytes. More...

constexpr uint32_t	FIL_PAGE_FILE_FLUSH_LSN = 26
	this is only defined for the first page of the system tablespace: the file has been flushed to disk at least up to this LSN. More...

constexpr uint32_t	FIL_PAGE_VERSION = FIL_PAGE_FILE_FLUSH_LSN
	If page type is FIL_PAGE_COMPRESSED then the 8 bytes starting at FIL_PAGE_FILE_FLUSH_LSN are broken down as follows: More...

constexpr uint32_t	FIL_PAGE_ALGORITHM_V1 = FIL_PAGE_VERSION + 1
	Compression algorithm (u8) More...

constexpr uint32_t	FIL_PAGE_ORIGINAL_TYPE_V1 = FIL_PAGE_ALGORITHM_V1 + 1
	Original page type (u16) More...

constexpr uint32_t	FIL_PAGE_ORIGINAL_SIZE_V1 = FIL_PAGE_ORIGINAL_TYPE_V1 + 2
	Original data size in bytes (u16) More...

constexpr uint32_t	FIL_PAGE_COMPRESS_SIZE_V1 = FIL_PAGE_ORIGINAL_SIZE_V1 + 2
	Size after compression (u16) More...

constexpr uint32_t	FIL_RTREE_SPLIT_SEQ_NUM = FIL_PAGE_FILE_FLUSH_LSN
	This overloads FIL_PAGE_FILE_FLUSH_LSN for RTREE Split Sequence Number. More...

constexpr uint32_t	FIL_PAGE_ARCH_LOG_NO_OR_SPACE_ID = 34
	starting from 4.1.x this contains the space id of the page More...

constexpr uint32_t	FIL_PAGE_SPACE_ID = FIL_PAGE_ARCH_LOG_NO_OR_SPACE_ID
	alias for space id More...

constexpr uint32_t	FIL_PAGE_DATA = 38
	start of the data on the page More...

constexpr uint32_t	FIL_PAGE_END_LSN_OLD_CHKSUM = 8
	File page trailer. More...

constexpr uint32_t	FIL_PAGE_DATA_END = 8
	size of the page trailer More...

constexpr size_t	FIL_ADDR_PAGE = 0
	First in address is the page offset. More...

constexpr size_t	FIL_ADDR_BYTE = 4
	Then comes 2-byte byte offset within page. More...

constexpr size_t	FIL_ADDR_SIZE = 6
	Address size is 6 bytes. More...

constexpr char	FIL_PATH_SEPARATOR = ';'
	Path separator e.g., 'dir;...;dirN'. More...

Detailed Description

The low-level file system page header & trailer offsets.

Created 10/25/1995 Heikki Tuuri

Function Documentation

◆ operator<<()

std::ostream & operator<<	(	std::ostream &	out,
		const Fil_page_header &	header
	)

inlinenoexcept

Overload the global output operator to handle an object of type Fil_page_header.

Parameters

[in]	out	the output stream.
[in]	header	an object of type Fil_page_header.

Returns: the output stream.

Variable Documentation

◆ FIL_ADDR_BYTE

constexpr size_t FIL_ADDR_BYTE = 4

constexpr

Then comes 2-byte byte offset within page.

◆ FIL_ADDR_PAGE

constexpr size_t FIL_ADDR_PAGE = 0

constexpr

First in address is the page offset.

◆ FIL_ADDR_SIZE

constexpr size_t FIL_ADDR_SIZE = 6

constexpr

Address size is 6 bytes.

◆ FIL_PAGE_ALGORITHM_V1

constexpr uint32_t FIL_PAGE_ALGORITHM_V1 = FIL_PAGE_VERSION + 1

constexpr

Compression algorithm (u8)

◆ FIL_PAGE_ARCH_LOG_NO_OR_SPACE_ID

constexpr uint32_t FIL_PAGE_ARCH_LOG_NO_OR_SPACE_ID = 34

constexpr

starting from 4.1.x this contains the space id of the page

◆ FIL_PAGE_COMPRESS_SIZE_V1

constexpr uint32_t FIL_PAGE_COMPRESS_SIZE_V1 = FIL_PAGE_ORIGINAL_SIZE_V1 + 2

constexpr

Size after compression (u16)

◆ FIL_PAGE_DATA

constexpr uint32_t FIL_PAGE_DATA = 38

constexpr

start of the data on the page

◆ FIL_PAGE_DATA_END

constexpr uint32_t FIL_PAGE_DATA_END = 8

constexpr

size of the page trailer

◆ FIL_PAGE_END_LSN_OLD_CHKSUM

constexpr uint32_t FIL_PAGE_END_LSN_OLD_CHKSUM = 8

constexpr

File page trailer.

the low 4 bytes of this are used to store the page checksum, the last 4 bytes should be identical to the last 4 bytes of FIL_PAGE_LSN

◆ FIL_PAGE_FILE_FLUSH_LSN

constexpr uint32_t FIL_PAGE_FILE_FLUSH_LSN = 26

constexpr

this is only defined for the first page of the system tablespace: the file has been flushed to disk at least up to this LSN.

For FIL_PAGE_COMPRESSED pages, we store the compressed page control information in these 8 bytes.

◆ FIL_PAGE_LSN

constexpr uint32_t FIL_PAGE_LSN = 16

constexpr

lsn of the end of the newest modification log record to the page

◆ FIL_PAGE_NEXT

constexpr uint32_t FIL_PAGE_NEXT = 12

constexpr

if there is a 'natural' successor of the page, its offset.

Otherwise FIL_NULL. B-tree index pages(FIL_PAGE_TYPE contains FIL_PAGE_INDEX) on the same PAGE_LEVEL are maintained as a doubly linked list via FIL_PAGE_PREV and FIL_PAGE_NEXT in the collation order of the smallest user record on each page.

◆ FIL_PAGE_OFFSET

constexpr uint32_t FIL_PAGE_OFFSET = 4

constexpr

page offset inside space

◆ FIL_PAGE_ORIGINAL_SIZE_V1

constexpr uint32_t FIL_PAGE_ORIGINAL_SIZE_V1 = FIL_PAGE_ORIGINAL_TYPE_V1 + 2

constexpr

Original data size in bytes (u16)

◆ FIL_PAGE_ORIGINAL_TYPE_V1

constexpr uint32_t FIL_PAGE_ORIGINAL_TYPE_V1 = FIL_PAGE_ALGORITHM_V1 + 1

constexpr

Original page type (u16)

◆ FIL_PAGE_PREV

constexpr uint32_t FIL_PAGE_PREV = 8

constexpr

if there is a 'natural' predecessor of the page, its offset.

Otherwise FIL_NULL. This field is not set on BLOB pages, which are stored as a singly-linked list. See also FIL_PAGE_NEXT.

◆ FIL_PAGE_SPACE_ID

constexpr uint32_t FIL_PAGE_SPACE_ID = FIL_PAGE_ARCH_LOG_NO_OR_SPACE_ID

constexpr

alias for space id

◆ FIL_PAGE_SPACE_OR_CHKSUM

constexpr uint32_t FIL_PAGE_SPACE_OR_CHKSUM = 0

constexpr

The byte offsets on a file page for various variables.

MySQL-4.0.14 space id the page belongs to (== 0) but in later versions the 'new' checksum of the page

◆ FIL_PAGE_SPACE_VERSION

constexpr uint32_t FIL_PAGE_SPACE_VERSION = 12

constexpr

On page 0 of the tablespace, this is the server version ID.

◆ FIL_PAGE_SRV_VERSION

constexpr uint32_t FIL_PAGE_SRV_VERSION = 8

constexpr

On page 0 of the tablespace, this is the server version ID.

◆ FIL_PAGE_TYPE

constexpr uint32_t FIL_PAGE_TYPE = 24

constexpr

file page type: FIL_PAGE_INDEX,..., 2 bytes.

The contents of this field can only be trusted in the following case: if the page is an uncompressed B-tree index page, then it is guaranteed that the value is FIL_PAGE_INDEX. The opposite does not hold.

In tablespaces created by MySQL/InnoDB 5.1.7 or later, the contents of this field is valid for all uncompressed pages.

◆ FIL_PAGE_VERSION

constexpr uint32_t FIL_PAGE_VERSION = FIL_PAGE_FILE_FLUSH_LSN

constexpr

If page type is FIL_PAGE_COMPRESSED then the 8 bytes starting at FIL_PAGE_FILE_FLUSH_LSN are broken down as follows:

Control information version format (u8)

◆ FIL_PATH_SEPARATOR

constexpr char FIL_PATH_SEPARATOR = ';'

constexpr

Path separator e.g., 'dir;...;dirN'.

◆ FIL_RTREE_SPLIT_SEQ_NUM

constexpr uint32_t FIL_RTREE_SPLIT_SEQ_NUM = FIL_PAGE_FILE_FLUSH_LSN

constexpr

This overloads FIL_PAGE_FILE_FLUSH_LSN for RTREE Split Sequence Number.

Classes

Functions

Variables

Detailed Description

Function Documentation

◆ operator<<()

Variable Documentation

◆ FIL_ADDR_BYTE

◆ FIL_ADDR_PAGE

◆ FIL_ADDR_SIZE

◆ FIL_PAGE_ALGORITHM_V1

◆ FIL_PAGE_ARCH_LOG_NO_OR_SPACE_ID

◆ FIL_PAGE_COMPRESS_SIZE_V1

◆ FIL_PAGE_DATA

◆ FIL_PAGE_DATA_END

◆ FIL_PAGE_END_LSN_OLD_CHKSUM

◆ FIL_PAGE_FILE_FLUSH_LSN

◆ FIL_PAGE_LSN

◆ FIL_PAGE_NEXT

◆ FIL_PAGE_OFFSET

◆ FIL_PAGE_ORIGINAL_SIZE_V1

◆ FIL_PAGE_ORIGINAL_TYPE_V1

◆ FIL_PAGE_PREV

◆ FIL_PAGE_SPACE_ID

◆ FIL_PAGE_SPACE_OR_CHKSUM

◆ FIL_PAGE_SPACE_VERSION

◆ FIL_PAGE_SRV_VERSION

◆ FIL_PAGE_TYPE

◆ FIL_PAGE_VERSION

◆ FIL_PATH_SEPARATOR

◆ FIL_RTREE_SPLIT_SEQ_NUM