The log0files_io. More...

#include <string>
#include "log0types.h"
#include "mach0data.h"
#include "ut0crc32.h"
#include "ut0new.h"

Functions
bool	log_header_checksum_is_ok (const byte *buf)
	Computes checksum of the given header and verifies if the checksum is the same as the one stored in that header. More...

Log - file header read/write.
void	log_file_header_serialize (const Log_file_header &header, byte *buf)
	Serializes the log file header to the buffer. More...

bool	log_file_header_deserialize (const byte *buf, Log_file_header &header)
	Deserializes the log file header stored in the buffer. More...

dberr_t	log_file_header_write (Log_file_handle &file_handle, const Log_file_header &header)
	Serializes and writes the log file header to the log file. More...

dberr_t	log_file_header_write (Log_file_handle &file_handle, const byte *buf)
	Writes the serialized log file header to the log file. More...

dberr_t	log_file_header_read (Log_file_handle &file_handle, byte *buf)
	Reads the serialized log file header to the buffer. More...

dberr_t	log_file_header_read (Log_file_handle &file_handle, Log_file_header &header)
	Reads and deserializes the log file header. More...

void	log_file_header_set_flag (Log_flags &log_flags, uint32_t bit)
	Sets a specific flag in the mask built of redo log flags. More...

void	log_file_header_reset_flag (Log_flags &log_flags, uint32_t bit)
	Resets a specific flag in the mask built of redo log flags. More...

bool	log_file_header_check_flag (Log_flags log_flags, uint32_t bit)
	Checks if a specific flag is set in the mask built of redo log flags. More...

Log - encryption header read/write.
dberr_t	log_encryption_header_write (Log_file_handle &file_handle, const byte *buf)
	Writes the serialized encryption meta data to the log file. More...

dberr_t	log_encryption_header_read (Log_file_handle &file_handle, byte *buf)
	Reads the serialized encryption meta data from the log file. More...

Log - checkpoint header read/write.
void	log_checkpoint_header_serialize (const Log_checkpoint_header &header, byte *buf)
	Serializes the log checkpoint header to the buffer. More...

bool	log_checkpoint_header_deserialize (const byte *buf, Log_checkpoint_header &header)
	Deserializes the log checkpoint header stored in the buffer. More...

dberr_t	log_checkpoint_header_write (Log_file_handle &file_handle, Log_checkpoint_header_no checkpoint_header_no, const Log_checkpoint_header &header)
	Serializes and writes the log checkpoint header to the log file. More...

dberr_t	log_checkpoint_header_write (Log_file_handle &file_handle, Log_checkpoint_header_no checkpoint_header_no, const byte *buf)
	Writes the serialized checkpoint header to the log file. More...

dberr_t	log_checkpoint_header_read (Log_file_handle &file_handle, Log_checkpoint_header_no checkpoint_header_no, byte *buf)
	Reads the serialized log checkpoint header to the buffer. More...

dberr_t	log_checkpoint_header_read (Log_file_handle &file_handle, Log_checkpoint_header_no checkpoint_header_no, Log_checkpoint_header &header)
	Reads and deserializes the log checkpoint header. More...

Log functions - data blocks read/write.
dberr_t	log_data_blocks_write (Log_file_handle &file_handle, os_offset_t write_offset, size_t write_size, const byte *buf)
	Writes the formatted log blocks with redo records to the log file. More...

dberr_t	log_data_blocks_read (Log_file_handle &file_handle, os_offset_t read_offset, size_t read_size, byte *buf)
	Reads log blocks with redo records from the log file, starting at the given offset. More...

Log - files creation/deletion, path computation.
std::string	log_directory_path (const Log_files_context &ctx)
	Provides path to directory with redo log files. More...

std::string	log_file_name (const Log_files_context &ctx, Log_file_id file_id)
	Provides name of the log file with the given file id, e.g. More...

std::string	log_file_path (const Log_files_context &ctx, Log_file_id file_id)
	Provides full path to the log file, e.g. More...

std::string	log_file_path_for_unused_file (const Log_files_context &ctx, Log_file_id file_id)
	Provides full path to the temporary log file, e.g. More...

dberr_t	log_list_existing_files (const Log_files_context &ctx, ut::vector< Log_file_id > &ret)
	List existing log files in the directory (does not include unused files). More...

dberr_t	log_list_existing_unused_files (const Log_files_context &ctx, ut::vector< Log_file_id > &ret)
	List existing unused log files in the directory. More...

dberr_t	log_rename_unused_file (const Log_files_context &ctx, Log_file_id old_unused_file_id, Log_file_id new_unused_file_id)
	Renames the unused file to another unused file. More...

dberr_t	log_mark_file_as_in_use (const Log_files_context &ctx, Log_file_id file_id)
	Renames a temporary log file to the non-temporary log file. More...

dberr_t	log_mark_file_as_unused (const Log_files_context &ctx, Log_file_id file_id)
	Renames a non-temporary log file to the temporary log file. More...

dberr_t	log_remove_unused_file (const Log_files_context &ctx, Log_file_id file_id)
	Removes a temporary log file, if it existed. More...

std::pair< dberr_t, ut::vector< Log_file_id > >	log_remove_unused_files (const Log_files_context &ctx)
	Removes all temporary log files in the directory. More...

dberr_t	log_remove_file (const Log_files_context &ctx, Log_file_id file_id)
	Removes a log file, if it existed. More...

std::pair< dberr_t, Log_file_id >	log_remove_file (const Log_files_context &ctx)
	Removes a single existing log file (if it existed). More...

std::pair< dberr_t, ut::vector< Log_file_id > >	log_remove_files (const Log_files_context &ctx)
	Removes existing log files. More...

dberr_t	log_create_unused_file (const Log_files_context &ctx, Log_file_id file_id, os_offset_t size_in_bytes)
	Creates a new temporary log file and resizes the file to the given size. More...

dberr_t	log_resize_unused_file (const Log_files_context &ctx, Log_file_id file_id, os_offset_t size_in_bytes)
	Resizes an existing temporary log file to the given size. More...

dberr_t	log_resize_file (const Log_files_context &ctx, Log_file_id file_id, os_offset_t size_in_bytes)
	Resizes an existing log file to the given size. More...

dberr_t	log_collect_existing_files (const Log_files_context &ctx, bool read_only, ut::vector< Log_file_id_and_size > &found)
	Searches for all possible log files existing on disk in the log directory. More...

Log_uuid	log_generate_uuid ()
	Generate unique identifier for the redo log files. More...

Log - log blocks format.
uint32_t	log_block_get_hdr_no (const byte *log_block)
	Gets a log block number stored in the header. More...

void	log_block_set_hdr_no (byte *log_block, uint32_t n)
	Sets the log block number stored in the header. More...

uint32_t	log_block_get_data_len (const byte *log_block)
	Gets a log block data length. More...

void	log_block_set_data_len (byte *log_block, uint32_t len)
	Sets the log block data length. More...

uint32_t	log_block_get_first_rec_group (const byte *log_block)
	Gets an offset to the beginning of the first group of log records in a given log block. More...

void	log_block_set_first_rec_group (byte *log_block, uint32_t offset)
	Sets an offset to the beginning of the first group of log records in a given log block. More...

uint32_t	log_block_get_epoch_no (const byte *log_block)
	Gets a log block epoch_no. More...

void	log_block_set_epoch_no (byte *log_block, uint32_t no)
	Sets a log block epoch_no. More...

uint32_t	log_block_convert_lsn_to_epoch_no (lsn_t lsn)
	Converts a lsn to a log block epoch number. More...

uint32_t	log_block_convert_lsn_to_hdr_no (lsn_t lsn)
	Converts a lsn to a log block number. More...

uint32_t	log_block_calc_checksum (const byte *log_block)
	Calculates the checksum for a log block. More...

uint32_t	log_block_calc_checksum_crc32 (const byte *log_block)
	Calculates the checksum for a log block using the MySQL 5.7 algorithm. More...

uint32_t	log_block_calc_checksum_none (const byte *)
	Calculates the checksum for a log block using the "no-op" algorithm. More...

uint32_t	log_block_get_checksum (const byte *log_block)
	Gets value of a log block checksum field. More...

void	log_block_set_checksum (byte *log_block, uint32_t checksum)
	Sets value of a log block checksum field. More...

void	log_block_store_checksum (byte *log_block)
	Stores a 4-byte checksum to the trailer checksum field of a log block. More...

bool	log_block_get_encrypt_bit (const byte *log_block)
	Gets value of a log block encrypt bit (true or false). More...

void	log_block_set_encrypt_bit (byte *log_block, bool val)
	Sets value of a log block encrypt bit (true or false). More...

void	log_data_block_header_serialize (const Log_data_block_header &header, byte *buf)
	Serializes the log data block header to the redo log block buffer which already contains redo log data (must have the redo data before this call). More...

bool	log_data_block_header_deserialize (const byte *buf, Log_data_block_header &header)
	Deserializes the log data block header stored in the buffer. More...

Variables
Log_checksum_algorithm_atomic_ptr	log_checksum_algorithm_ptr
	Atomic pointer to the log checksum calculation function. More...

Detailed Description

The log0files_io.

{cc,h} is a low-level independent library for IO operations performed directly on redo log files.

The library provides functions which allow to:

serialize,
deserialize,
read,
or write each kind of header stored in redo log files, and individual redo log blocks.

NOTE: Parsing of individual redo records is NOT in scope of this library.

Remarks

Main goal for this library is to make IO operations simpler, no matter what is the motivation behind reading or writing fragments of redo log files.

That's why:

Functions defined in this library form a set of simple independent tools. They are state-less (they do not change state of the library, but obviously "write" functions might change redo log files).
For each kind of redo header, three forms of the header are recognized:
- structure with typed fields (e.g. struct Log_checkpoint_header),
- array of bytes representing the serialized header,
- data stored on disk. Functions to translate between any two of these forms are provided for each kind of header. In order to make life easier (when having to remind yourself what was the name for the given function), the following naming convention has been defined:
- structure -> array of bytes: log_X_header_serialize,
- array of bytes -> structure: log_X_header_deserialize,
- structure -> disk: log_X_header_write(Log_file_id, ..., const The_struct& ),
- disk -> structure: log_X_header_read(Log_file_id, ..., The_struct& ),
- array of bytes -> disk: log_X_header_write(Log_file_id, ..., const byte* ),
- disk -> array of bytes: log_X_header_read(Log_file_id, ..., byte* ).

Note: There is no structure with typed fields for encryption header (yet) and for redo data blocks.

The functions defined in this library MUST NOT depend on log_t or recovery implementation, because this library is designed to be lightweight and easy to use.

Note

Functions that operate on set of redo files are also part of this library. This includes functions to:

build a path to the redo log file with the given id,
list existing redo files,
remove redo files,
create empty redo files,
mark/unmark individual redo files as unused.

Function Documentation

◆ log_block_calc_checksum()

uint32_t log_block_calc_checksum ( const byte * log_block )

inline

Calculates the checksum for a log block.

Parameters

[in] log_block log block

Returns: checksum

◆ log_block_calc_checksum_crc32()

uint32_t log_block_calc_checksum_crc32 ( const byte * log_block )

inline

Calculates the checksum for a log block using the MySQL 5.7 algorithm.

Parameters

[in] log_block log block

Returns: checksum

◆ log_block_calc_checksum_none()

uint32_t log_block_calc_checksum_none ( const byte * )

inline

Calculates the checksum for a log block using the "no-op" algorithm.

Returns: checksum

◆ log_block_convert_lsn_to_epoch_no()

uint32_t log_block_convert_lsn_to_epoch_no ( lsn_t lsn )

inline

Converts a lsn to a log block epoch number.

For details

See also: LOG_BLOCK_EPOCH_NO.

Parameters

[in] lsn lsn of a byte within the block

Returns: log block epoch number, it is > 0

◆ log_block_convert_lsn_to_hdr_no()

uint32_t log_block_convert_lsn_to_hdr_no ( lsn_t lsn )

inline

Converts a lsn to a log block number.

Consecutive log blocks have consecutive numbers (unless the sequence wraps). It is guaranteed that the calculated number is greater than zero.

Parameters

[in] lsn lsn of a byte within the block

Returns: log block number, it is > 0 and <= 1G

◆ log_block_get_checksum()

uint32_t log_block_get_checksum ( const byte * log_block )

inline

Gets value of a log block checksum field.

Parameters

[in] log_block log block

Returns: checksum

◆ log_block_get_data_len()

uint32_t log_block_get_data_len ( const byte * log_block )

inline

Gets a log block data length.

Parameters

[in] log_block log block

Returns: log block data length measured as a byte offset from the block start

◆ log_block_get_encrypt_bit()

bool log_block_get_encrypt_bit ( const byte * log_block )

inline

Gets value of a log block encrypt bit (true or false).

Parameters

[in] log_block log block

Returns: true iff encrypt bit is set

◆ log_block_get_epoch_no()

uint32_t log_block_get_epoch_no ( const byte * log_block )

inline

Gets a log block epoch_no.

For details:

See also: LOG_BLOCK_EPOCH_NO.

Parameters

[in] log_block log block

Returns: epoch number

◆ log_block_get_first_rec_group()

uint32_t log_block_get_first_rec_group ( const byte * log_block )

inline

Gets an offset to the beginning of the first group of log records in a given log block.

Parameters

[in] log_block log block

Returns: first mtr log record group byte offset from the block start, 0 if none.

◆ log_block_get_hdr_no()

uint32_t log_block_get_hdr_no ( const byte * log_block )

inline

Gets a log block number stored in the header.

The number corresponds to lsn range for data stored in the block.

During recovery, when a next block is being parsed, a next range of lsn values is expected to be read. This corresponds to a log block number increased by one (modulo LOG_BLOCK_MAX_NO). However, if an unexpected number is read from the header, it is then considered the end of the redo log and recovery is finished. In such case, the next block is most likely an empty block or a block from the past, because the redo log files might be reused.

Parameters

[in] log_block log block (may be invalid or empty block)

Returns: log block number stored in the block header

◆ log_block_set_checksum()

void log_block_set_checksum	(	byte *	log_block,
		uint32_t	checksum
	)

inline

Sets value of a log block checksum field.

Parameters

[in,out]	log_block	log block
[in]	checksum	checksum

◆ log_block_set_data_len()

void log_block_set_data_len	(	byte *	log_block,
		uint32_t	len
	)

inline

Sets the log block data length.

Parameters

[in,out]	log_block	log block
[in]	len	data length (

See also: log_block_get_data_len)

◆ log_block_set_encrypt_bit()

void log_block_set_encrypt_bit	(	byte *	log_block,
		bool	val
	)

inline

Sets value of a log block encrypt bit (true or false).

Parameters

[in]	log_block	log block to modify
[in]	val	the value to set (true or false)

◆ log_block_set_epoch_no()

void log_block_set_epoch_no	(	byte *	log_block,
		uint32_t	no
	)

inline

Sets a log block epoch_no.

For details:

See also: LOG_BLOCK_EPOCH_NO.

Parameters

[in,out]	log_block	log block
[in]	no	epoch number

◆ log_block_set_first_rec_group()

void log_block_set_first_rec_group	(	byte *	log_block,
		uint32_t	offset
	)

inline

Sets an offset to the beginning of the first group of log records in a given log block.

Parameters

[in,out]	log_block	log block
[in]	offset	offset, 0 if none

◆ log_block_set_hdr_no()

void log_block_set_hdr_no	(	byte *	log_block,
		uint32_t	n
	)

inline

Sets the log block number stored in the header.

NOTE that this must be set before the flush bit!

Parameters

[in,out]	log_block	log block
[in]	n	log block number: must be in (0, 1G]

◆ log_block_store_checksum()

void log_block_store_checksum ( byte * log_block )

inline

Stores a 4-byte checksum to the trailer checksum field of a log block.

This is used before writing the log block to disk. The checksum in a log block is used in recovery to check the consistency of the log block.

Parameters

[in] log_block log block (completely filled in!)

◆ log_checkpoint_header_deserialize()

bool log_checkpoint_header_deserialize	(	const byte *	buf,
		Log_checkpoint_header &	header
	)

Deserializes the log checkpoint header stored in the buffer.

Parameters

[in]	buf	the buffer to deserialize
[out]	header	the deserialized header

Returns: true iff checksum is correct

◆ log_checkpoint_header_read() [1/2]

dberr_t log_checkpoint_header_read	(	Log_file_handle &	file_handle,
		Log_checkpoint_header_no	checkpoint_header_no,
		byte *	buf
	)

Reads the serialized log checkpoint header to the buffer.

Parameters

[in]	file_handle	handle for the opened log file
[in]	checkpoint_header_no	checkpoint header to read
[out]	buf	the allocated buffer for read

Returns: DB_SUCCESS or error

◆ log_checkpoint_header_read() [2/2]

dberr_t log_checkpoint_header_read	(	Log_file_handle &	file_handle,
		Log_checkpoint_header_no	checkpoint_header_no,
		Log_checkpoint_header &	header
	)

Reads and deserializes the log checkpoint header.

Parameters

[in]	file_handle	handle for the opened log file
[in]	checkpoint_header_no	checkpoint header to read
[out]	header	the checkpoint header read

Returns: DB_SUCCESS or error

◆ log_checkpoint_header_serialize()

void log_checkpoint_header_serialize	(	const Log_checkpoint_header &	header,
		byte *	buf
	)

Serializes the log checkpoint header to the buffer.

Parameters

[in]	header	the header to serialize
[out]	buf	the allocated buffer

◆ log_checkpoint_header_write() [1/2]

dberr_t log_checkpoint_header_write	(	Log_file_handle &	file_handle,
		Log_checkpoint_header_no	checkpoint_header_no,
		const byte *	buf
	)

Writes the serialized checkpoint header to the log file.

Parameters

[in]	file_handle	handle for the opened log file
[in]	checkpoint_header_no	checkpoint header to be written
[in]	buf	buffer containing the serialized checkpoint header to write

Returns: DB_SUCCESS or error

◆ log_checkpoint_header_write() [2/2]

dberr_t log_checkpoint_header_write	(	Log_file_handle &	file_handle,
		Log_checkpoint_header_no	checkpoint_header_no,
		const Log_checkpoint_header &	header
	)

Serializes and writes the log checkpoint header to the log file.

Parameters

[in]	file_handle	handle for the opened log file
[in]	checkpoint_header_no	checkpoint header to be written
[in]	header	the checkpoint header

Returns: DB_SUCCESS or error

◆ log_collect_existing_files()

dberr_t log_collect_existing_files	(	const Log_files_context &	ctx,
		bool	read_only,
		ut::vector< Log_file_id_and_size > &	found
	)

Searches for all possible log files existing on disk in the log directory.

Performs only very minimal validation of the files, checking if files could be opened and have valid file size.

Parameters

[in]	ctx	context within which files exist
[in]	read_only	true: check file permissions only for reading, false: check for both reading and writing
[out]	found	list of <file_id, size of file> for each file found

Returns: DB_SUCCESS, DB_NOT_FOUND or DB_ERROR

◆ log_create_unused_file()

dberr_t log_create_unused_file	(	const Log_files_context &	ctx,
		Log_file_id	file_id,
		os_offset_t	size_in_bytes
	)

Creates a new temporary log file and resizes the file to the given size.

Parameters

[in]	ctx	context within which files exist
[in]	file_id	id of the file to create
[in]	size_in_bytes	size of the file, in bytes

Returns: DB_SUCCESS or DB_ERROR

◆ log_data_block_header_deserialize()

bool log_data_block_header_deserialize	(	const byte *	buf,
		Log_data_block_header &	header
	)

inline

Deserializes the log data block header stored in the buffer.

Parameters

[in]	buf	the buffer to deserialize
[out]	header	the deserialized header

Returns: true iff checksum is correct

◆ log_data_block_header_serialize()

void log_data_block_header_serialize	(	const Log_data_block_header &	header,
		byte *	buf
	)

inline

Serializes the log data block header to the redo log block buffer which already contains redo log data (must have the redo data before this call).

Parameters

[in]	header	the header to serialize
[out]	buf	the buffer containing the redo log block with the data

◆ log_data_blocks_read()

dberr_t log_data_blocks_read	(	Log_file_handle &	file_handle,
		os_offset_t	read_offset,
		size_t	read_size,
		byte *	buf
	)

Reads log blocks with redo records from the log file, starting at the given offset.

The log blocks must exist within single log file.

Parameters

[in]	file_handle	handle for the opened log file
[in]	read_offset	offset from the beginning of the given file
[in]	read_size	size of the data to read (must be divisible by OS_FILE_LOG_BLOCK_SIZE)
[out]	buf	allocated buffer to fill by the read

Returns: DB_SUCCESS or error

◆ log_data_blocks_write()

dberr_t log_data_blocks_write	(	Log_file_handle &	file_handle,
		os_offset_t	write_offset,
		size_t	write_size,
		const byte *	buf
	)

Writes the formatted log blocks with redo records to the log file.

The given log blocks must fit within the same single log file.

Parameters

[in]	file_handle	handle for the opened log file
[in]	write_offset	offset from the beginning of the given file
[in]	write_size	size of the data to write (must be divisible by OS_FILE_LOG_BLOCK_SIZE)
[in]	buf	formatted log blocks with the data to write

Returns: DB_SUCCESS or error

◆ log_directory_path()

std::string log_directory_path ( const Log_files_context & ctx )

Provides path to directory with redo log files.

Parameters

[in] ctx context within which files exist

Returns: path to innodb_redo directory

◆ log_encryption_header_read()

dberr_t log_encryption_header_read	(	Log_file_handle &	file_handle,
		byte *	buf
	)

Reads the serialized encryption meta data from the log file.

Parameters

[in]	file_handle	handle for the opened log file
[out]	buf	the allocated buffer for read

Returns: DB_SUCCESS or error

◆ log_encryption_header_write()

dberr_t log_encryption_header_write	(	Log_file_handle &	file_handle,
		const byte *	buf
	)

Writes the serialized encryption meta data to the log file.

Parameters

[in]	file_handle	handle for the opened log file
[in]	buf	the filled encryption buffer to write

Returns: DB_SUCCESS or error

◆ log_file_header_check_flag()

bool log_file_header_check_flag	(	Log_flags	log_flags,
		uint32_t	bit
	)

Checks if a specific flag is set in the mask built of redo log flags.

Parameters

[in]	log_flags	mask of log flags
[in]	bit	bit number to check (flag)

Returns: true, iff flag is set

◆ log_file_header_deserialize()

bool log_file_header_deserialize	(	const byte *	buf,
		Log_file_header &	header
	)

Deserializes the log file header stored in the buffer.

Parameters

[in]	buf	the buffer to deserialize
[out]	header	the deserialized header

Returns: true iff checksum is correct

◆ log_file_header_read() [1/2]

dberr_t log_file_header_read	(	Log_file_handle &	file_handle,
		byte *	buf
	)

Reads the serialized log file header to the buffer.

Parameters

[in]	file_handle	handle for the opened log file
[out]	buf	the allocated buffer for read

Returns: DB_SUCCESS or error

◆ log_file_header_read() [2/2]

dberr_t log_file_header_read	(	Log_file_handle &	file_handle,
		Log_file_header &	header
	)

Reads and deserializes the log file header.

Parameters

[in]	file_handle	handle for the opened log file
[out]	header	the file header read

Returns: DB_SUCCESS or error

◆ log_file_header_reset_flag()

void log_file_header_reset_flag	(	Log_flags &	log_flags,
		uint32_t	bit
	)

Resets a specific flag in the mask built of redo log flags.

Parameters

[in]	log_flags	mask of log flags
[in]	bit	bit number to set (flag)

◆ log_file_header_serialize()

void log_file_header_serialize	(	const Log_file_header &	header,
		byte *	buf
	)

Serializes the log file header to the buffer.

Parameters

[in]	header	the header to serialize
[out]	buf	the allocated buffer

◆ log_file_header_set_flag()

void log_file_header_set_flag	(	Log_flags &	log_flags,
		uint32_t	bit
	)

Sets a specific flag in the mask built of redo log flags.

Parameters

[in]	log_flags	mask of log flags
[in]	bit	bit number to set (flag)

◆ log_file_header_write() [1/2]

dberr_t log_file_header_write	(	Log_file_handle &	file_handle,
		const byte *	buf
	)

Writes the serialized log file header to the log file.

Parameters

[in]	file_handle	handle for the opened log file
[in]	buf	the serialized file header

Returns: DB_SUCCESS or error

◆ log_file_header_write() [2/2]

dberr_t log_file_header_write	(	Log_file_handle &	file_handle,
		const Log_file_header &	header
	)

Serializes and writes the log file header to the log file.

Parameters

[in]	file_handle	handle for the opened log file
[in]	header	the file header

Returns: DB_SUCCESS or error

◆ log_file_name()

std::string log_file_name	(	const Log_files_context &	ctx,
		Log_file_id	file_id
	)

Provides name of the log file with the given file id, e.g.

'ib_redo0'.

Parameters

[in]	ctx	context within which files exist
[in]	file_id	id of the log file

Returns: file name

◆ log_file_path()

std::string log_file_path	(	const Log_files_context &	ctx,
		Log_file_id	file_id
	)

Provides full path to the log file, e.g.

'/data/innodb_redo/ib_redo2'.

Parameters

[in]	ctx	context within which files exist
[in]	file_id	id of the log file

Returns: path to the log file (including file name)

◆ log_file_path_for_unused_file()

std::string log_file_path_for_unused_file	(	const Log_files_context &	ctx,
		Log_file_id	file_id
	)

Provides full path to the temporary log file, e.g.

'/data/innodb_redo/ib_redo2_tmp'.

Parameters

[in]	ctx	context within which files exist
[in]	file_id	id of the file

Returns: path to the temporary log file (including file name)

◆ log_generate_uuid()

Log_uuid log_generate_uuid ( )

Generate unique identifier for the redo log files.

Returns: random uuid > 0

◆ log_header_checksum_is_ok()

bool log_header_checksum_is_ok ( const byte * buf )

Computes checksum of the given header and verifies if the checksum is the same as the one stored in that header.

Parameters

[in] buf header to verify

Returns: true iff checksums are the same

◆ log_list_existing_files()

dberr_t log_list_existing_files	(	const Log_files_context &	ctx,
		ut::vector< Log_file_id > &	ret
	)

List existing log files in the directory (does not include unused files).

Parameters

[in]	ctx	context within which files exist
[out]	ret	identifiers of existing log files

Returns: DB_SUCCESS or DB_ERROR

◆ log_list_existing_unused_files()

dberr_t log_list_existing_unused_files	(	const Log_files_context &	ctx,
		ut::vector< Log_file_id > &	ret
	)

List existing unused log files in the directory.

Parameters

[in]	ctx	context within which files exist
[out]	ret	identifiers of existing unused log files

Returns: DB_SUCCESS or DB_ERROR

◆ log_mark_file_as_in_use()

dberr_t log_mark_file_as_in_use	(	const Log_files_context &	ctx,
		Log_file_id	file_id
	)

Renames a temporary log file to the non-temporary log file.

Parameters

[in]	ctx	context within which files exist
[in]	file_id	id of the file to rename

Returns: DB_SUCCESS or DB_ERROR

◆ log_mark_file_as_unused()

dberr_t log_mark_file_as_unused	(	const Log_files_context &	ctx,
		Log_file_id	file_id
	)

Renames a non-temporary log file to the temporary log file.

Parameters

[in]	ctx	context within which files exist
[in]	file_id	id of the file to rename

Returns: DB_SUCCESS or DB_ERROR

◆ log_remove_file() [1/2]

std::pair< dberr_t, Log_file_id > log_remove_file ( const Log_files_context & ctx )

Removes a single existing log file (if it existed).

Parameters

[in] ctx context within which files exist

Returns: first: DB_SUCCESS, DB_NOT_FOUND or DB_ERROR second: id of the removed file (if removed)

◆ log_remove_file() [2/2]

dberr_t log_remove_file	(	const Log_files_context &	ctx,
		Log_file_id	file_id
	)

Removes a log file, if it existed.

Parameters

[in]	ctx	context within which files exist
[in]	file_id	id of the file to remove

Returns: DB_SUCCESS, DB_NOT_FOUND or DB_ERROR

◆ log_remove_files()

std::pair< dberr_t, ut::vector< Log_file_id > > log_remove_files ( const Log_files_context & ctx )

Removes existing log files.

When failed to remove a file, stops and returns error. In such case the last element of the returned identifiers of files, represents the file for which error has been encountered when trying to remove it.

Parameters

[in] ctx context within which files exist

Returns: first: DB_SUCCESS or DB_ERROR second: identifiers of files for which remove has been called

◆ log_remove_unused_file()

dberr_t log_remove_unused_file	(	const Log_files_context &	ctx,
		Log_file_id	file_id
	)

Removes a temporary log file, if it existed.

Parameters

[in]	ctx	context within which files exist
[in]	file_id	id of the file to remove

Returns: DB_SUCCESS, DB_NOT_FOUND or DB_ERROR

◆ log_remove_unused_files()

std::pair< dberr_t, ut::vector< Log_file_id > > log_remove_unused_files ( const Log_files_context & ctx )

Removes all temporary log files in the directory.

When failed to remove a file, stops and returns error. In such case the last element of the returned identifiers of files, represents the file for which error has been encountered when trying to remove it.

Parameters

[in] ctx context within which files exist

Returns: first: DB_SUCCESS or DB_ERROR second: identifiers of files for which remove has been called

◆ log_rename_unused_file()

dberr_t log_rename_unused_file	(	const Log_files_context &	ctx,
		Log_file_id	old_unused_file_id,
		Log_file_id	new_unused_file_id
	)

Renames the unused file to another unused file.

Parameters

[in]	ctx	context within which files exist
[in]	old_unused_file_id	id of file to rename
[in]	new_unused_file_id	new file id

Returns: DB_SUCCESS or DB_ERROR

◆ log_resize_file()

dberr_t log_resize_file	(	const Log_files_context &	ctx,
		Log_file_id	file_id,
		os_offset_t	size_in_bytes
	)

Resizes an existing log file to the given size.

Parameters

[in]	ctx	context within which files exist
[in]	file_id	id of the file to resize
[in]	size_in_bytes	requested size of the file, in bytes

Returns: DB_SUCCESS, DB_NOT_FOUND, DB_OUT_OF_DISK_SPACE or DB_ERROR

◆ log_resize_unused_file()

dberr_t log_resize_unused_file	(	const Log_files_context &	ctx,
		Log_file_id	file_id,
		os_offset_t	size_in_bytes
	)

Resizes an existing temporary log file to the given size.

Parameters

[in]	ctx	context within which files exist
[in]	file_id	id of the file to resize
[in]	size_in_bytes	requested size of the file, in bytes

Returns: DB_SUCCESS, DB_NOT_FOUND, DB_OUT_OF_DISK_SPACE or DB_ERROR

Variable Documentation

◆ log_checksum_algorithm_ptr

Log_checksum_algorithm_atomic_ptr log_checksum_algorithm_ptr

extern

Atomic pointer to the log checksum calculation function.

This is actually the only remaining "state" of the library. Hopefully can become removed.

Functions

Variables

Detailed Description

Function Documentation

◆ log_block_calc_checksum()

◆ log_block_calc_checksum_crc32()

◆ log_block_calc_checksum_none()

◆ log_block_convert_lsn_to_epoch_no()

◆ log_block_convert_lsn_to_hdr_no()

◆ log_block_get_checksum()

◆ log_block_get_data_len()

◆ log_block_get_encrypt_bit()

◆ log_block_get_epoch_no()

◆ log_block_get_first_rec_group()

◆ log_block_get_hdr_no()

◆ log_block_set_checksum()

◆ log_block_set_data_len()

◆ log_block_set_encrypt_bit()

◆ log_block_set_epoch_no()

◆ log_block_set_first_rec_group()

◆ log_block_set_hdr_no()

◆ log_block_store_checksum()

◆ log_checkpoint_header_deserialize()

◆ log_checkpoint_header_read() [1/2]

◆ log_checkpoint_header_read() [2/2]

◆ log_checkpoint_header_serialize()

◆ log_checkpoint_header_write() [1/2]

◆ log_checkpoint_header_write() [2/2]

◆ log_collect_existing_files()

◆ log_create_unused_file()

◆ log_data_block_header_deserialize()

◆ log_data_block_header_serialize()

◆ log_data_blocks_read()

◆ log_data_blocks_write()

◆ log_directory_path()

◆ log_encryption_header_read()

◆ log_encryption_header_write()

◆ log_file_header_check_flag()

◆ log_file_header_deserialize()

◆ log_file_header_read() [1/2]

◆ log_file_header_read() [2/2]

◆ log_file_header_reset_flag()

◆ log_file_header_serialize()

◆ log_file_header_set_flag()

◆ log_file_header_write() [1/2]

◆ log_file_header_write() [2/2]

◆ log_file_name()

◆ log_file_path()

◆ log_file_path_for_unused_file()

◆ log_generate_uuid()

◆ log_header_checksum_is_ok()

◆ log_list_existing_files()

◆ log_list_existing_unused_files()

◆ log_mark_file_as_in_use()

◆ log_mark_file_as_unused()

◆ log_remove_file() [1/2]

◆ log_remove_file() [2/2]

◆ log_remove_files()

◆ log_remove_unused_file()

◆ log_remove_unused_files()

◆ log_rename_unused_file()

◆ log_resize_file()

◆ log_resize_unused_file()

Variable Documentation

◆ log_checksum_algorithm_ptr