os0file.h File Reference

The interface to the operating system file io. More...

#include "my_dbug.h"
#include "my_io.h"
#include "os/file.h"
#include "os0atomic.h"
#include "os0enc.h"
#include <dirent.h>
#include <sys/stat.h>
#include <sys/statvfs.h>
#include <time.h>
#include <functional>
#include <stack>
#include "os0file.ic"

Go to the source code of this file.

Classes
struct	file::Block
	Blocks for doing IO, used in the transparent compression and encryption code. More...
struct	pfs_os_file_t
	Common file descriptor for file IO instrumentation with PFS on windows and other platforms. More...
class	IORequest
	The IO Context that is passed down to the low level IO code. More...
struct	os_file_size_t
	Sparse file size information. More...
struct	os_file_stat_t
	Struct used in fetching information of a file in a directory. More...
class	Dir_Walker
	Class to scan the directory hierarchy using a depth first scan. More...
struct	Dir_Walker::Entry
	Directory names for the depth first directory scan. More...
class	SyncFileIO
	Helper class for doing synchronous file IO. More...

Namespaces
namespace	file

Macros
#define	OS_FILE_PREFIX   "#"
	Prefix all files and directory created under data directory with special string so that it never conflicts with MySQL schema directory. More...
#define	OS_FILE_FROM_FD(fd)   fd
	Convert a C file descriptor to a native file handle. More...
#define	OS_FD_FROM_FILE(file)   file
	C file descriptor from an existing native file handle. More...
#define	OS_FILE_CLOSE_FD(fd)   (os_file_close(fd) ? 0 : OS_FD_CLOSED)
	Closes the file associated with C file descriptor fd. More...
#define	register_pfs_file_open_begin(state, locker, key, op, name, src_location)
#define	register_pfs_file_open_end(locker, file, result)
#define	register_pfs_file_rename_begin(state, locker, key, op, from, to, src_location)
#define	register_pfs_file_rename_end(locker, from, to, result)
#define	register_pfs_file_close_begin(state, locker, key, op, name, src_location)
#define	register_pfs_file_close_end(locker, result)
#define	register_pfs_file_io_begin(state, locker, file, count, op, src_location)
#define	register_pfs_file_io_end(locker, count)
#define	os_file_create(key, name, create, purpose, read_only, success)
#define	os_file_create_simple_no_error_handling(key, name, create_mode, access, read_only, success)
#define	os_file_create_simple_no_error_handling_with_umask( key, name, create_mode, access, read_only, umask, success)
#define	os_file_close_pfs(file)   pfs_os_file_close_func(file, UT_LOCATION_HERE)
#define	os_aio(type, mode, name, file, buf, offset, n, read_only, message1, message2)
#define	os_file_read_pfs(type, file_name, file, buf, offset, n)    pfs_os_file_read_func(type, file_name, file, buf, offset, n, UT_LOCATION_HERE)
#define	os_file_read_first_page_pfs(type, file_name, file, buf, n)
#define	os_file_copy_pfs(src, src_offset, dest, dest_offset, size)
#define	os_file_read_no_error_handling_pfs(type, file_name, file, buf, offset, n, o)
#define	os_file_read_no_error_handling_int_fd(type, file_name, file, buf, offset, n, o)
#define	os_file_write_pfs(type, name, file, buf, offset, n)    pfs_os_file_write_func(type, name, file, buf, offset, n, UT_LOCATION_HERE)
#define	os_file_write_int_fd(type, name, file, buf, offset, n)
#define	os_file_flush_pfs(file)   pfs_os_file_flush_func(file, UT_LOCATION_HERE)
#define	os_file_rename(key, oldpath, newpath)    pfs_os_file_rename_func(key, oldpath, newpath, UT_LOCATION_HERE)
#define	os_file_delete(key, name)    pfs_os_file_delete_func(key, name, UT_LOCATION_HERE)
#define	os_file_delete_if_exists(key, name, exist)    pfs_os_file_delete_if_exists_func(key, name, exist, UT_LOCATION_HERE)
#define	os_file_close(file)   os_file_close_pfs(file)
#define	os_file_read(type, file_name, file, buf, offset, n)    os_file_read_pfs(type, file_name, file, buf, offset, n)
#define	os_file_read_first_page(type, file_name, file, buf, n)    os_file_read_first_page_pfs(type, file_name, file, buf, n)
#define	os_file_flush(file)   os_file_flush_pfs(file)
#define	os_file_write(type, name, file, buf, offset, n)    os_file_write_pfs(type, name, file, buf, offset, n)
#define	os_file_copy(src, src_offset, dest, dest_offset, size)    os_file_copy_pfs(src, src_offset, dest, dest_offset, size)
#define	os_file_read_no_error_handling(type, file_name, file, buf, offset, n, o)    os_file_read_no_error_handling_pfs(type, file_name, file, buf, offset, n, o)
#define	IORequestRead   IORequest(IORequest::READ)
	Types for AIO operations. More...
#define	IORequestWrite   IORequest(IORequest::WRITE)

Typedefs
typedef uint64_t	os_offset_t
	File offset in bytes. More...
using	os_fd_t = int
	Raw file handle. More...
using	os_file_t = os_fd_t
	File handle. More...
typedef std::function< void(const char *path, const char *name)>	os_dir_cbk_t
	Callback function type to be implemented by caller. More...

Enumerations
enum	os_file_type_t {   OS_FILE_TYPE_FAILED , OS_FILE_TYPE_NAME_TOO_LONG , OS_FILE_PERMISSION_ERROR , OS_FILE_TYPE_MISSING ,   OS_FILE_TYPE_UNKNOWN , OS_FILE_TYPE_FILE , OS_FILE_TYPE_DIR , OS_FILE_TYPE_LINK ,   OS_FILE_TYPE_BLOCK }
enum class	AIO_mode : size_t { NORMAL = 21 , IBUF = 22 , SYNC = 24 }
	Modes for aio operations. More...

Functions
FILE *	os_file_create_tmpfile ()
	Create a temporary file. More...
bool	os_file_create_directory (const char *pathname, bool fail_if_exists)
	This function attempts to create a directory named pathname. More...
bool	os_file_scan_directory (const char *path, os_dir_cbk_t scan_cbk, bool is_drop)
	This function scans the contents of a directory and invokes the callback for each entry. More...
pfs_os_file_t	os_file_create_simple_no_error_handling_func (const char *name, ulint create_mode, ulint access_type, bool read_only, mode_t umask, bool *success)
	Clang on Windows warns about umask not found. More...
void	os_file_set_nocache (int fd, const char *file_name, const char *operation_name)
	Tries to disable OS caching on an opened file descriptor. More...
pfs_os_file_t	os_file_create_func (const char *name, ulint create_mode, ulint purpose, bool read_only, bool *success)
	NOTE! Use the corresponding macro os_file_create(), not directly this function! Opens an existing file or creates a new. More...
bool	os_file_delete_func (const char *name)
	Deletes a file. More...
bool	os_file_delete_if_exists_func (const char *name, bool *exist)
	Deletes a file if it exists. More...
bool	os_file_rename_func (const char *oldpath, const char *newpath)
	NOTE! Use the corresponding macro os_file_rename(), not directly this function! Renames a file (can also move it to another directory). More...
bool	os_file_close_func (os_file_t file)
	NOTE! Use the corresponding macro os_file_close(), not directly this function! Closes a file handle. More...
static pfs_os_file_t	pfs_os_file_create_simple_no_error_handling_func (mysql_pfs_key_t key, const char *name, ulint create_mode, ulint access_type, bool read_only, mode_t umask, bool *success, ut::Location src_location)
	Clang on Windows warns about umask not found. More...
static pfs_os_file_t	pfs_os_file_create_func (mysql_pfs_key_t key, const char *name, ulint create_mode, ulint purpose, bool read_only, bool *success, ut::Location src_location)
	NOTE! Please use the corresponding macro os_file_create(), not directly this function! A performance schema wrapper function for os_file_create(). More...
static bool	pfs_os_file_close_func (pfs_os_file_t file, ut::Location src_location)
	NOTE! Please use the corresponding macro os_file_close(), not directly this function! A performance schema instrumented wrapper function for os_file_close(). More...
static dberr_t	pfs_os_file_read_func (IORequest &type, const char *file_name, pfs_os_file_t file, void *buf, os_offset_t offset, ulint n, ut::Location src_location)
	NOTE! Please use the corresponding macro os_file_read(), not directly this function! This is the performance schema instrumented wrapper function for os_file_read() which requests a synchronous read operation. More...
static dberr_t	pfs_os_file_read_first_page_func (IORequest &type, const char *file_name, pfs_os_file_t file, void *buf, ulint n, ut::Location src_location)
	NOTE! Please use the corresponding macro os_file_read_first_page(), not directly this function! This is the performance schema instrumented wrapper function for os_file_read_first_page() which requests a synchronous read operation of page 0 of IBD file. More...
static dberr_t	pfs_os_file_copy_func (pfs_os_file_t src, os_offset_t src_offset, pfs_os_file_t dest, os_offset_t dest_offset, uint size, ut::Location src_location)
	copy data from one file to another file. More...
static dberr_t	pfs_os_file_read_no_error_handling_func (IORequest &type, const char *file_name, pfs_os_file_t file, void *buf, os_offset_t offset, ulint n, ulint *o, ut::Location src_location)
	NOTE! Please use the corresponding macro os_file_read_no_error_handling(), not directly this function! This is the performance schema instrumented wrapper function for os_file_read_no_error_handling_func() which requests a synchronous read operation. More...
static dberr_t	pfs_os_file_read_no_error_handling_int_fd_func (IORequest &type, const char *file_name, int file, void *buf, os_offset_t offset, ulint n, ulint *o, ut::Location src_location)
	NOTE! Please use the corresponding macro os_file_read_no_error_handling_int_fd(), not directly this function! This is the performance schema instrumented wrapper function for os_file_read_no_error_handling_int_fd_func() which requests a synchronous read operation on files with int type descriptors. More...
static dberr_t	pfs_os_aio_func (IORequest &type, AIO_mode mode, const char *name, pfs_os_file_t file, void *buf, os_offset_t offset, ulint n, bool read_only, fil_node_t *m1, void *m2, ut::Location location)
	NOTE! Please use the corresponding macro os_aio(), not directly this function! Performance schema wrapper function of os_aio() which requests an asynchronous I/O operation. More...
static dberr_t	pfs_os_file_write_func (IORequest &type, const char *name, pfs_os_file_t file, const void *buf, os_offset_t offset, ulint n, ut::Location src_location)
	NOTE! Please use the corresponding macro os_file_write(), not directly this function! This is the performance schema instrumented wrapper function for os_file_write() which requests a synchronous write operation. More...
static dberr_t	pfs_os_file_write_int_fd_func (IORequest &type, const char *name, int file, const void *buf, os_offset_t offset, ulint n, ut::Location src_location)
	NOTE! Please use the corresponding macro os_file_write(), not directly this function! This is the performance schema instrumented wrapper function for os_file_write() which requests a synchronous write operation on files with int type descriptors. More...
static bool	pfs_os_file_flush_func (pfs_os_file_t file, ut::Location src_location)
	NOTE! Please use the corresponding macro os_file_flush(), not directly this function! This is the performance schema instrumented wrapper function for os_file_flush() which flushes the write buffers of a given file to the disk. More...
static bool	pfs_os_file_rename_func (mysql_pfs_key_t key, const char *oldpath, const char *newpath, ut::Location src_location)
	NOTE! Please use the corresponding macro os_file_rename(), not directly this function! This is the performance schema instrumented wrapper function for os_file_rename() More...
static bool	pfs_os_file_delete_func (mysql_pfs_key_t key, const char *name, ut::Location src_location)
	NOTE! Please use the corresponding macro os_file_delete(), not directly this function! This is the performance schema instrumented wrapper function for os_file_delete() More...
static bool	pfs_os_file_delete_if_exists_func (mysql_pfs_key_t key, const char *name, bool *exist, ut::Location src_location)
	NOTE! Please use the corresponding macro os_file_delete_if_exists(), not directly this function! This is the performance schema instrumented wrapper function for os_file_delete_if_exists() More...
os_file_size_t	os_file_get_size (const char *filename)
	Gets a file size. More...
os_offset_t	os_file_get_size (pfs_os_file_t file)
	Gets a file size. More...
bool	os_file_set_size_fast (const char *name, pfs_os_file_t file, os_offset_t offset, os_offset_t size, bool flush)
	Allocate a block to file using fallocate from the given offset if fallocate is supported. More...
bool	os_file_set_size (const char *name, pfs_os_file_t file, os_offset_t offset, os_offset_t size, bool flush)
	Write the specified number of zeros to a file from specific offset. More...
bool	os_file_set_eof (FILE *file)
	Truncates a file at its current position. More...
bool	os_file_truncate (const char *pathname, pfs_os_file_t file, os_offset_t size)
	Truncates a file to a specified size in bytes. More...
bool	os_file_seek (const char *pathname, os_file_t file, os_offset_t offset)
	Set read/write position of a file handle to specific offset. More...
bool	os_file_flush_func (os_file_t file)
	NOTE! Use the corresponding macro os_file_flush(), not directly this function! Flushes the write buffers of a given file to the disk. More...
ulint	os_file_get_last_error (bool report_all_errors)
	Retrieves the last error number if an error occurs in a file io function. More...
dberr_t	os_file_read_func (IORequest &type, const char *file_name, os_file_t file, void *buf, os_offset_t offset, ulint n)
	NOTE! Use the corresponding macro os_file_read_first_page(), not directly this function! Requests a synchronous read operation of page 0 of IBD file. More...
dberr_t	os_file_read_first_page_func (IORequest &type, const char *file_name, os_file_t file, void *buf, ulint n)
	NOTE! Use the corresponding macro os_file_read_first_page(), not directly this function! Requests a synchronous read operation of page 0 of IBD file. More...
dberr_t	os_file_copy_func (os_file_t src_file, os_offset_t src_offset, os_file_t dest_file, os_offset_t dest_offset, uint size)
	Copy data from one file to another file. More...
void	os_file_read_string (FILE *file, char *str, ulint size)
	Rewind file to its start, read at most size - 1 bytes from it to str, and NUL-terminate str. More...
dberr_t	os_file_read_no_error_handling_func (IORequest &type, const char *file_name, os_file_t file, void *buf, os_offset_t offset, ulint n, ulint *o)
	NOTE! Use the corresponding macro os_file_read_no_error_handling(), not directly this function! Requests a synchronous positioned read operation. More...
dberr_t	os_file_write_func (IORequest &type, const char *name, os_file_t file, const void *buf, os_offset_t offset, ulint n)
	NOTE! Use the corresponding macro os_file_write(), not directly this function! Requests a synchronous write operation. More...
bool	os_file_status (const char *path, bool *exists, os_file_type_t *type)
	Check the existence and type of a given path. More...
bool	os_file_exists (const char *path)
	Check the existence and usefulness of a given path. More...
dberr_t	os_file_create_subdirs_if_needed (const char *path)
	Create all missing subdirectories along the given path. More...
void	os_create_block_cache ()
	Creates and initializes block_cache. More...
bool	os_aio_init (ulint n_readers, ulint n_writers)
	Initializes the asynchronous io system. More...
void	os_aio_start_threads ()
	Starts one thread for each segment created in os_aio_init. More...
void	os_aio_free ()
	Frees the asynchronous io system. More...
dberr_t	os_aio_func (IORequest &type, AIO_mode aio_mode, const char *name, pfs_os_file_t file, void *buf, os_offset_t offset, ulint n, bool read_only, fil_node_t *m1, void *m2)
	NOTE! Use the corresponding macro os_aio(), not directly this function! Requests an asynchronous i/o operation. More...
void	os_aio_wake_all_threads_at_shutdown ()
	Wakes up all async i/o threads so that they know to exit themselves in shutdown. More...
void	os_aio_wait_until_no_pending_writes ()
	Waits until there are no pending writes in os_aio_write_array. More...
void	os_aio_simulated_wake_handler_threads ()
	Wakes up simulated aio i/o-handler threads if they have something to do. More...
void	os_aio_simulated_put_read_threads_to_sleep ()
	This function can be called if one wants to post a batch of reads and prefers an i/o-handler thread to handle them all at once later. More...
dberr_t	os_aio_handler (ulint segment, fil_node_t **m1, void **m2, IORequest *request)
	Waits for an AIO operation to complete. More...
void	os_aio_print (FILE *file)
	Prints info of the aio arrays. More...
void	os_aio_refresh_stats ()
	Refreshes the statistics used to print per-second averages. More...
bool	os_aio_all_slots_free ()
	Checks that all slots in the system have been freed, that is, there are no pending io operations. More...
void	os_aio_print_pending_io (FILE *file)
	Prints all pending IO. More...
dberr_t	os_get_free_space (const char *path, uint64_t &free_space)
	Get available free space on disk. More...
dberr_t	os_file_get_status (const char *path, os_file_stat_t *stat_info, bool check_rw_perm, bool read_only)
	This function returns information about the specified file. More...
bool	os_file_check_mode (const char *name, bool read_only)
	Check if a file can be opened in read-write mode. More...
char *	innobase_mysql_tmpdir ()
	return any of the tmpdir path More...
os_fd_t	innobase_mysql_tmpfile (const char *path)
	Creates a temporary file in the location specified by the parameter path. More...
ulint	os_file_compressed_page_size (const byte *buf)
	If it is a compressed page return the compressed page data + footer size. More...
ulint	os_file_original_page_size (const byte *buf)
	If it is a compressed page return the original page data + footer size. More...
void	os_file_set_umask (mode_t umask)
	Set the global file create umask. More...
dberr_t	os_file_punch_hole (os_file_t fh, os_offset_t off, os_offset_t len)
	Free storage space associated with a section of the file. More...
bool	os_is_sparse_file_supported (pfs_os_file_t fh)
	Check if the file system supports sparse files. More...
dberr_t	os_file_decompress_page (bool dblwr_read, byte *src, byte *dst, ulint dst_len)
	Decompress the page data contents. More...
byte *	os_file_compress_page (Compression compression, ulint block_size, byte *src, ulint src_len, byte *dst, ulint *dst_len)
	Compress a data page. More...
bool	os_is_o_direct_supported ()
	Determine if O_DIRECT is supported. More...
dberr_t	os_file_write_zeros (pfs_os_file_t file, const char *name, ulint page_size, os_offset_t start, ulint len)
	Fill the pages with NULs. More...
file::Block *	os_alloc_block () noexcept
	Allocate a page for sync IO. More...
byte *	os_block_get_frame (const file::Block *block) noexcept
	Get the sector aligned frame pointer. More...
void	os_free_block (file::Block *block) noexcept
	Free a page after sync IO. More...
file::Block *	os_file_encrypt_page (const IORequest &type, void *&buf, ulint n)
	Encrypt a page content when write it to disk. More...
file::Block *	os_file_compress_page (IORequest &type, void *&buf, ulint *n)
	Allocate the buffer for IO on a transparently compressed table. More...
dberr_t	os_file_write_retry (IORequest &type, const char *name, pfs_os_file_t file, const void *buf, os_offset_t offset, ulint n)
	This is a wrapper function for the os_file_write() function call. More...

Variables
bool	os_has_said_disk_full
constexpr size_t	NUM_RETRIES_ON_PARTIAL_IO = 10
	Number of retries for partial I/O's. More...
std::atomic< ulint >	os_n_pending_reads
	Number of pending read operations. More...
std::atomic< ulint >	os_n_pending_writes
	Number of pending write operations. More...
unsigned long long	os_fsync_threshold
static constexpr os_fd_t	OS_FD_CLOSED = -1
static constexpr os_fd_t	OS_FILE_CLOSED = OS_FD_CLOSED
constexpr uint32_t	OS_FILE_LOG_BLOCK_SIZE = 512
	The next value should be smaller or equal to the smallest sector size used on any disk. More...
static const ulint	OS_AIO_N_PENDING_IOS_PER_THREAD = 32
	Win NT does not allow more than 64. More...
ulint	os_n_file_reads
ulint	os_n_file_writes
ulint	os_n_fsyncs
constexpr uint32_t	OS_FILE_MAX_PATH = 4000
mysql_pfs_key_t	innodb_log_file_key
mysql_pfs_key_t	innodb_temp_file_key
mysql_pfs_key_t	innodb_dblwr_file_key
mysql_pfs_key_t	innodb_arch_file_key
mysql_pfs_key_t	innodb_clone_file_key
mysql_pfs_key_t	innodb_data_file_key
mysql_pfs_key_t	innodb_tablespace_open_file_key
constexpr mode_t	os_innodb_umask_default = std::numeric_limits<mode_t>::max()
	A magic constant for the umask parameter that indicates caller wants the os_innodb_umask value to be used. More...
static const ulint	OS_DATA_FILE = 100
	Types for file create. More...
static const ulint	OS_LOG_FILE = 101
static const ulint	OS_LOG_FILE_RESIZING = 102
static const ulint	OS_BUFFERED_FILE = 103
static const ulint	OS_CLONE_DATA_FILE = 104
static const ulint	OS_CLONE_LOG_FILE = 105
static const ulint	OS_DBLWR_FILE = 106
static const ulint	OS_FILE_NOT_FOUND = 71
	Error codes from os_file_get_last_error. More...
static const ulint	OS_FILE_DISK_FULL = 72
static const ulint	OS_FILE_ALREADY_EXISTS = 73
static const ulint	OS_FILE_PATH_ERROR = 74
static const ulint	OS_FILE_AIO_RESOURCES_RESERVED = 75
	wait for OS aio resources to become available again More...
static const ulint	OS_FILE_SHARING_VIOLATION = 76
static const ulint	OS_FILE_ERROR_NOT_SPECIFIED = 77
static const ulint	OS_FILE_INSUFFICIENT_RESOURCE = 78
static const ulint	OS_FILE_AIO_INTERRUPTED = 79
static const ulint	OS_FILE_OPERATION_ABORTED = 80
static const ulint	OS_FILE_ACCESS_VIOLATION = 81
static const ulint	OS_FILE_NAME_TOO_LONG = 82
static const ulint	OS_FILE_TOO_MANY_OPENED = 83
static const ulint	OS_FILE_ERROR_MAX = 100
enum	os_file_create_t {   OS_FILE_OPEN = 51 , OS_FILE_CREATE , OS_FILE_OPEN_RAW , OS_FILE_CREATE_PATH ,   OS_FILE_OPEN_RETRY , OS_FILE_ON_ERROR_NO_EXIT = 128 , OS_FILE_ON_ERROR_SILENT = 256 }
	Options for os_file_create_func. More...
static const ulint	OS_FILE_READ_ONLY = 333
static const ulint	OS_FILE_READ_WRITE = 444
static const ulint	OS_FILE_READ_ALLOW_DELETE = 555
	Used by MySQLBackup. More...

Detailed Description

The interface to the operating system file io.

Created 10/21/1995 Heikki Tuuri

Macro Definition Documentation

IORequestRead

#define IORequestRead   IORequest(IORequest::READ)

Types for AIO operations.

No transformations during read/write, write as is.

IORequestWrite

#define IORequestWrite   IORequest(IORequest::WRITE)

os_aio

#define os_aio	(		type,
			mode,
			name,
			file,
			buf,
			offset,
			n,
			read_only,
			message1,
			message2
	)

Value:

  pfs_os_aio_func(type, mode, name, file, buf, offset, n, read_only, message1, \
                  message2, UT_LOCATION_HERE)

OS_FD_FROM_FILE

#define OS_FD_FROM_FILE

(

file

)

file

C file descriptor from an existing native file handle.

Parameters

[in]

file

native file handle

Returns

C file descriptor

os_file_close

#define os_file_close

(

file

)

os_file_close_pfs(file)

OS_FILE_CLOSE_FD

#define OS_FILE_CLOSE_FD

(

fd

)

(os_file_close(fd) ? 0 : OS_FD_CLOSED)

Closes the file associated with C file descriptor fd.

Parameters

[in]

fd

C file descriptor

Returns

0 if success

os_file_close_pfs

#define os_file_close_pfs

(

file

)

pfs_os_file_close_func(file, UT_LOCATION_HERE)

os_file_copy

#define os_file_copy	(		src,
			src_offset,
			dest,
			dest_offset,
			size
	)		os_file_copy_pfs(src, src_offset, dest, dest_offset, size)

os_file_copy_pfs

#define os_file_copy_pfs	(		src,
			src_offset,
			dest,
			dest_offset,
			size
	)

Value:

  pfs_os_file_copy_func(src, src_offset, dest, dest_offset, size,  \
                        UT_LOCATION_HERE)

os_file_create

#define os_file_create	(		key,
			name,
			create,
			purpose,
			read_only,
			success
	)

Value:

  pfs_os_file_create_func(key, name, create, purpose, read_only, success, \
                          UT_LOCATION_HERE)

os_file_create_simple_no_error_handling

#define os_file_create_simple_no_error_handling	(		key,
			name,
			create_mode,
			access,
			read_only,
			success
	)

Value:

  pfs_os_file_create_simple_no_error_handling_func(                         \
      key, name, create_mode, access, read_only, os_innodb_umask_default,   \
      success, UT_LOCATION_HERE)

os_file_create_simple_no_error_handling_with_umask

#define os_file_create_simple_no_error_handling_with_umask	(		key,
			name,
			create_mode,
			access,
			read_only,
			umask,
			success
	)

Value:

  pfs_os_file_create_simple_no_error_handling_func(key, name, create_mode,   \
                                                   access, read_only, umask, \
                                                   success, UT_LOCATION_HERE)

os_file_delete

#define os_file_delete	(		key,
			name
	)		pfs_os_file_delete_func(key, name, UT_LOCATION_HERE)

os_file_delete_if_exists

#define os_file_delete_if_exists	(		key,
			name,
			exist
	)		pfs_os_file_delete_if_exists_func(key, name, exist, UT_LOCATION_HERE)

os_file_flush

#define os_file_flush

(

file

)

os_file_flush_pfs(file)

os_file_flush_pfs

#define os_file_flush_pfs

(

file

)

pfs_os_file_flush_func(file, UT_LOCATION_HERE)

OS_FILE_FROM_FD

#define OS_FILE_FROM_FD

(

fd

)

fd

Convert a C file descriptor to a native file handle.

Parameters

fd	file descriptor

Returns

native file handle

OS_FILE_PREFIX

#define OS_FILE_PREFIX   "#"

Prefix all files and directory created under data directory with special string so that it never conflicts with MySQL schema directory.

os_file_read

#define os_file_read	(		type,
			file_name,
			file,
			buf,
			offset,
			n
	)		os_file_read_pfs(type, file_name, file, buf, offset, n)

os_file_read_first_page

#define os_file_read_first_page	(		type,
			file_name,
			file,
			buf,
			n
	)		os_file_read_first_page_pfs(type, file_name, file, buf, n)

os_file_read_first_page_pfs

#define os_file_read_first_page_pfs	(		type,
			file_name,
			file,
			buf,
			n
	)

Value:

  pfs_os_file_read_first_page_func(type, file_name, file, buf, n,  \
                                   UT_LOCATION_HERE)

os_file_read_no_error_handling

#define os_file_read_no_error_handling	(		type,
			file_name,
			file,
			buf,
			offset,
			n,
			o
	)		os_file_read_no_error_handling_pfs(type, file_name, file, buf, offset, n, o)

os_file_read_no_error_handling_int_fd

#define os_file_read_no_error_handling_int_fd	(		type,
			file_name,
			file,
			buf,
			offset,
			n,
			o
	)

Value:

  pfs_os_file_read_no_error_handling_int_fd_func(                         \
      type, file_name, file, buf, offset, n, o, UT_LOCATION_HERE)

os_file_read_no_error_handling_pfs

#define os_file_read_no_error_handling_pfs	(		type,
			file_name,
			file,
			buf,
			offset,
			n,
			o
	)

Value:

  pfs_os_file_read_no_error_handling_func(type, file_name, file, buf, offset,  \
                                          n, o, UT_LOCATION_HERE)

os_file_read_pfs

#define os_file_read_pfs	(		type,
			file_name,
			file,
			buf,
			offset,
			n
	)		pfs_os_file_read_func(type, file_name, file, buf, offset, n, UT_LOCATION_HERE)

os_file_rename

#define os_file_rename	(		key,
			oldpath,
			newpath
	)		pfs_os_file_rename_func(key, oldpath, newpath, UT_LOCATION_HERE)

os_file_write

#define os_file_write	(		type,
			name,
			file,
			buf,
			offset,
			n
	)		os_file_write_pfs(type, name, file, buf, offset, n)

os_file_write_int_fd

#define os_file_write_int_fd	(		type,
			name,
			file,
			buf,
			offset,
			n
	)

Value:

  pfs_os_file_write_int_fd_func(type, name, file, buf, offset, n, \
                                UT_LOCATION_HERE)

os_file_write_pfs

#define os_file_write_pfs	(		type,
			name,
			file,
			buf,
			offset,
			n
	)		pfs_os_file_write_func(type, name, file, buf, offset, n, UT_LOCATION_HERE)

register_pfs_file_close_begin

#define register_pfs_file_close_begin	(		state,
			locker,
			key,
			op,
			name,
			src_location
	)

Value:

  do {                                                                       \
    locker = PSI_FILE_CALL(get_thread_file_name_locker)(state, key.m_value,  \
                                                        op, name, &locker);  \
    if (locker != nullptr) {                                                 \
      PSI_FILE_CALL(start_file_close_wait)                                   \
      (locker, src_location.filename, static_cast<uint>(src_location.line)); \
    }                                                                        \
  } while (0)

register_pfs_file_close_end

#define register_pfs_file_close_end	(		locker,
			result
	)

Value:

  do {                                                    \
    if (locker != nullptr) {                              \
      PSI_FILE_CALL(end_file_close_wait)(locker, result); \
    }                                                     \
  } while (0)

register_pfs_file_io_begin

#define register_pfs_file_io_begin	(		state,
			locker,
			file,
			count,
			op,
			src_location
	)

Value:

  do {                                                                       \
    locker =                                                                 \
        PSI_FILE_CALL(get_thread_file_stream_locker)(state, file.m_psi, op); \
    if (locker != nullptr) {                                                 \
      PSI_FILE_CALL(start_file_wait)                                         \
      (locker, count, src_location.filename,                                 \
       static_cast<uint>(src_location.line));                                \
    }                                                                        \
  } while (0)

register_pfs_file_io_end

#define register_pfs_file_io_end	(		locker,
			count
	)

Value:

  do {                                             \
    if (locker != nullptr) {                       \
      PSI_FILE_CALL(end_file_wait)(locker, count); \
    }                                              \
  } while (0)

register_pfs_file_open_begin

#define register_pfs_file_open_begin	(		state,
			locker,
			key,
			op,
			name,
			src_location
	)

Value:

  do {                                                                       \
    locker = PSI_FILE_CALL(get_thread_file_name_locker)(state, key.m_value,  \
                                                        op, name, &locker);  \
    if (locker != nullptr) {                                                 \
      PSI_FILE_CALL(start_file_open_wait)                                    \
      (locker, src_location.filename, static_cast<uint>(src_location.line)); \
    }                                                                        \
  } while (0)

register_pfs_file_open_end

#define register_pfs_file_open_end	(		locker,
			file,
			result
	)

Value:

  do {                                                                \
    if (locker != nullptr) {                                          \
      file.m_psi = PSI_FILE_CALL(end_file_open_wait)(locker, result); \
    }                                                                 \
  } while (0)

register_pfs_file_rename_begin

#define register_pfs_file_rename_begin	(		state,
			locker,
			key,
			op,
			from,
			to,
			src_location
	)

Value:

  do {                                                                      \
    locker = PSI_FILE_CALL(get_thread_file_name_locker)(state, key.m_value, \
                                                        op, from, &locker); \
    if (locker != nullptr) {                                                \
      PSI_FILE_CALL(start_file_rename_wait)                                 \
      (locker, (size_t)0, from, to, src_location.filename,                  \
       static_cast<uint>(src_location.line));                               \
    }                                                                       \
  } while (0)

register_pfs_file_rename_end

#define register_pfs_file_rename_end	(		locker,
			from,
			to,
			result
	)

Value:

  do {                                                               \
    if (locker != nullptr) {                                         \
      PSI_FILE_CALL(end_file_rename_wait)(locker, from, to, result); \
    }                                                                \
  } while (0)

Typedef Documentation

os_dir_cbk_t

typedef std::function<void(const char *path, const char *name)> os_dir_cbk_t

Callback function type to be implemented by caller.

It is called for each entry in directory.

Parameters

[in]	path	path to the file
[in]	name	name of the file

os_fd_t

using os_fd_t = int

Raw file handle.

os_file_t

using os_file_t = os_fd_t

File handle.

os_offset_t

typedef uint64_t os_offset_t

File offset in bytes.

Enumeration Type Documentation

AIO_mode

enum class AIO_mode : size_t

strong

Modes for aio operations.

Enumerator
NORMAL	Normal asynchronous i/o not for ibuf pages or ibuf bitmap pages.
IBUF	Asynchronous i/o for ibuf pages or ibuf bitmap pages.
SYNC	Asynchronous i/o where the calling thread will itself wait for the i/o to complete, doing also the job of the i/o-handler thread; can be used for any pages, ibuf or non-ibuf. This is used to save CPU time, as we can do with fewer thread switches. Plain synchronous I/O is not as good, because it must serialize the file seek and read or write, causing a bottleneck for parallelism.

os_file_create_t

enum os_file_create_t

Options for os_file_create_func.

Enumerator
OS_FILE_OPEN	to open an existing file (if doesn't exist, error)
OS_FILE_CREATE	to create new file (if exists, error)
OS_FILE_OPEN_RAW	to open a raw device or disk partition
OS_FILE_CREATE_PATH	to create the directories
OS_FILE_OPEN_RETRY	open with retry
OS_FILE_ON_ERROR_NO_EXIT	Flags that can be combined with the above values. Please ensure that the above values stay below 128. do not exit on unknown errors
OS_FILE_ON_ERROR_SILENT	don't print diagnostic messages to the log unless it is a fatal error, this flag is only used if ON_ERROR_NO_EXIT is set

os_file_type_t

enum os_file_type_t

Enumerator
OS_FILE_TYPE_FAILED	Get status failed.
OS_FILE_TYPE_NAME_TOO_LONG	stat() failed, with ENAMETOOLONG
OS_FILE_PERMISSION_ERROR	stat() failed with EACCESS
OS_FILE_TYPE_MISSING	File doesn't exist.
OS_FILE_TYPE_UNKNOWN	File exists but type is unknown.
OS_FILE_TYPE_FILE	Ordinary file.
OS_FILE_TYPE_DIR	Directory.
OS_FILE_TYPE_LINK	Symbolic link.
OS_FILE_TYPE_BLOCK	Block device.

Function Documentation

innobase_mysql_tmpdir()

char * innobase_mysql_tmpdir

(

)

return any of the tmpdir path

innobase_mysql_tmpfile()

os_fd_t innobase_mysql_tmpfile

(

const char *

path

)

Creates a temporary file in the location specified by the parameter path.

If the path is NULL, then it will be created in –tmpdir.

Parameters

[in]

path

location for creating temporary file

Returns

temporary file descriptor, or OS_FD_CLOSED on error

os_aio_all_slots_free()

bool os_aio_all_slots_free

(

)

Checks that all slots in the system have been freed, that is, there are no pending io operations.

Returns

true if all free

os_aio_free()

void os_aio_free

(

)

Frees the asynchronous io system.

os_aio_func()

dberr_t os_aio_func	(	IORequest &	type,
		AIO_mode	aio_mode,
		const char *	name,
		pfs_os_file_t	file,
		void *	buf,
		os_offset_t	offset,
		ulint	n,
		bool	read_only,
		fil_node_t *	m1,
		void *	m2
	)

NOTE! Use the corresponding macro os_aio(), not directly this function! Requests an asynchronous i/o operation.

Parameters

[in]	type	IO request context
[in]	aio_mode	IO mode
[in]	name	Name of the file or path as NUL terminated string
[in]	file	Open file handle
[out]	buf	buffer where to read
[in]	offset	file offset where to read
[in]	n	how many bytes to read or write; this must not cross a file boundary; in AIO this must be a block size multiple
[in]	read_only	if true read only mode checks are enforced
[in,out]	m1	Message for the AIO handler, (can be used to identify a completed AIO operation); ignored if mode is OS_AIO_SYNC
[in,out]	m2	message for the AIO handler (can be used to identify a completed AIO operation); ignored if mode is OS_AIO_SYNC

Returns

DB_SUCCESS or error code

os_aio_handler()

dberr_t os_aio_handler	(	ulint	segment,
		fil_node_t **	m1,
		void **	m2,
		IORequest *	request
	)

Waits for an AIO operation to complete.

This function is used to wait the for completed requests. The AIO array of pending requests is divided into segments. The thread specifies which segment or slot it wants to wait for. NOTE: this function will also take care of freeing the AIO slot, therefore no other thread is allowed to do the freeing!

Parameters

[in]	segment	The number of the segment in the AIO arrays to wait for; segment 0 is the ibuf I/O thread, then follow the non-ibuf read threads, and as the last are the non-ibuf write threads
[out]	m1	the messages passed with the AIO request; note that also in the case where the AIO operation failed, these output parameters are valid and can be used to restart the operation, for example
[out]	m2	callback message
[out]	request	OS_FILE_WRITE or ..._READ

Returns

DB_SUCCESS or error code

os_aio_init()

bool os_aio_init	(	ulint	n_readers,
		ulint	n_writers
	)

Initializes the asynchronous io system.

Creates an array for ibuf i/o (if not in read-only mode). Also creates one array each for read and write where each array is divided logically into n_readers and n_writers respectively. The caller must create an i/o handler thread for each segment in these arrays by calling os_aio_start_threads().

Parameters

[in]	n_readers	number of reader threads
[in]	n_writers	number of writer threads

os_aio_print()

void os_aio_print

(

FILE *

file

)

Prints info of the aio arrays.

Parameters

[in,out]

file

file where to print

os_aio_print_pending_io()

void os_aio_print_pending_io

(

FILE *

file

)

Prints all pending IO.

Parameters

[in]

file

File where to print

os_aio_refresh_stats()

void os_aio_refresh_stats

(

)

Refreshes the statistics used to print per-second averages.

os_aio_simulated_put_read_threads_to_sleep()

void os_aio_simulated_put_read_threads_to_sleep

(

)

This function can be called if one wants to post a batch of reads and prefers an i/o-handler thread to handle them all at once later.

You must call os_aio_simulated_wake_handler_threads later to ensure the threads are not left sleeping!

os_aio_simulated_wake_handler_threads()

void os_aio_simulated_wake_handler_threads

(

)

Wakes up simulated aio i/o-handler threads if they have something to do.

os_aio_start_threads()

void os_aio_start_threads

(

)

Starts one thread for each segment created in os_aio_init.

os_aio_wait_until_no_pending_writes()

void os_aio_wait_until_no_pending_writes

(

)

Waits until there are no pending writes in os_aio_write_array.

There can be other, synchronous, pending writes.

Waits until there are no pending writes in os_aio_write_array.

There can be other, synchronous, pending writes.

os_aio_wake_all_threads_at_shutdown()

void os_aio_wake_all_threads_at_shutdown

(

)

Wakes up all async i/o threads so that they know to exit themselves in shutdown.

os_alloc_block()

file::Block * os_alloc_block ( )

noexcept

Allocate a page for sync IO.

Returns

pointer to page

os_block_get_frame()

byte * os_block_get_frame ( const file::Block *  block )

noexcept

Get the sector aligned frame pointer.

Parameters

[in]

block

the memory block containing the page frame.

Returns

the sector aligned frame pointer.

os_create_block_cache()

void os_create_block_cache

(

)

Creates and initializes block_cache.

Creates array of MAX_BLOCKS and allocates the memory in each block to hold BUFFER_BLOCK_SIZE of data.

This function is called by InnoDB during srv_start(). It is also called by MEB while applying the redo logs on TDE tablespaces, the "Blocks" allocated in this block_cache are used to hold the decrypted page data.

os_file_check_mode()

bool os_file_check_mode	(	const char *	name,
		bool	read_only
	)

Check if a file can be opened in read-write mode.

Parameters

[in]	name	filename to check
[in]	read_only	true if check for read-only mode only

Return values

true	if file can be opened in the specified mode (rw or ro); or file does not exist
false	if file exists and can't be opened in the specified mode

os_file_close_func()

bool os_file_close_func

(

os_file_t

file

)

NOTE! Use the corresponding macro os_file_close(), not directly this function! Closes a file handle.

In case of error, error number can be retrieved with os_file_get_last_error.

Parameters

[in]

file

Handle to a file

Returns

true if success

os_file_compress_page() [1/2]

byte * os_file_compress_page	(	Compression	compression,
		ulint	block_size,
		byte *	src,
		ulint	src_len,
		byte *	dst,
		ulint *	dst_len
	)

Compress a data page.

Parameters

[in]	compression	Compression algorithm
[in]	block_size	File system block size
[in]	src	Source contents to compress
[in]	src_len	Length in bytes of the source
[out]	dst	Compressed page contents
[out]	dst_len	Length in bytes of dst contents

Returns

buffer data, dst_len will have the length of the data

os_file_compress_page() [2/2]

file::Block * os_file_compress_page	(	IORequest &	type,
		void *&	buf,
		ulint *	n
	)

Allocate the buffer for IO on a transparently compressed table.

Parameters

[in]	type	IO flags
[out]	buf	buffer to read or write
[in,out]	n	number of bytes to read/write, starting from offset

Returns

pointer to allocated page, compressed data is written to the offset that is aligned on the disk sector size

os_file_compressed_page_size()

ulint os_file_compressed_page_size

(

const byte *

buf

)

If it is a compressed page return the compressed page data + footer size.

Parameters

[in]

buf

Buffer to check, must include header + 10 bytes

Returns

ULINT_UNDEFINED if the page is not a compressed page or length of the compressed data (including footer) if it is a compressed page

os_file_copy_func()

dberr_t os_file_copy_func	(	os_file_t	src_file,
		os_offset_t	src_offset,
		os_file_t	dest_file,
		os_offset_t	dest_offset,
		uint	size
	)

Copy data from one file to another file.

Data is read/written at current file offset.

Parameters

[in]	src_file	file handle to copy from
[in]	src_offset	offset to copy from
[in]	dest_file	file handle to copy to
[in]	dest_offset	offset to copy to
[in]	size	number of bytes to copy

Returns

DB_SUCCESS if successful

os_file_create_directory()

bool os_file_create_directory	(	const char *	pathname,
		bool	fail_if_exists
	)

This function attempts to create a directory named pathname.

The new directory gets default permissions. On Unix the permissions are (0770 & ~umask). If the directory exists already, nothing is done and the call succeeds, unless the fail_if_exists arguments is true. If another error occurs, such as a permission error, this does not crash, but reports the error and returns false.

Parameters

[in]	pathname	directory name as null-terminated string
[in]	fail_if_exists	if true, pre-existing directory is treated as an error.

Returns

true if call succeeds, false on error

os_file_create_func()

pfs_os_file_t os_file_create_func	(	const char *	name,
		ulint	create_mode,
		ulint	purpose,
		bool	read_only,
		bool *	success
	)

NOTE! Use the corresponding macro os_file_create(), not directly this function! Opens an existing file or creates a new.

Parameters

[in]	name	name of the file or path as a null-terminated string
[in]	create_mode	create mode
[in]	purpose	OS_DATA_FILE, OS_LOG_FILE etc.
[in]	read_only	if true read only mode checks are enforced
[out]	success	true if succeeded

Returns

own: handle to the file, not defined if error, error number can be retrieved with os_file_get_last_error

os_file_create_simple_no_error_handling_func()

pfs_os_file_t os_file_create_simple_no_error_handling_func	(	const char *	name,
		ulint	create_mode,
		ulint	access_type,
		bool	read_only,
		mode_t	umask,
		bool *	success
	)

Clang on Windows warns about umask not found.

NOTE! Use the corresponding macro os_file_create_simple_no_error_handling(), not directly this function! A simple function to open or create a file.

Parameters

[in]	name	name of the file or path as a null-terminated string
[in]	create_mode	create mode
[in]	access_type	OS_FILE_READ_ONLY, OS_FILE_READ_WRITE, or OS_FILE_READ_ALLOW_DELETE; the last option is used by a backup program reading the file
[in]	read_only	if true read only mode checks are enforced
[in]	umask	UNIX access permission to be set when creating a file. Use os_umask_default to use global default umask.
[out]	success	true if succeeded

Returns

own: handle to the file, not defined if error, error number can be retrieved with os_file_get_last_error

os_file_create_subdirs_if_needed()

dberr_t os_file_create_subdirs_if_needed

(

const char *

path

)

Create all missing subdirectories along the given path.

Returns

DB_SUCCESS if OK, otherwise error code.

Create all missing subdirectories along the given path.

Parameters

[in]

path

Path name

Returns

DB_SUCCESS if OK, otherwise error code.

os_file_create_tmpfile()

FILE * os_file_create_tmpfile

(

)

Create a temporary file.

This function is like tmpfile(3). It will create the file in the MySQL server configuration parameter (–tmpdir).

Returns

temporary file handle, or NULL on error

os_file_decompress_page()

dberr_t os_file_decompress_page	(	bool	dblwr_read,
		byte *	src,
		byte *	dst,
		ulint	dst_len
	)

Decompress the page data contents.

Page type must be FIL_PAGE_COMPRESSED, if not then the source contents are left unchanged and DB_SUCCESS is returned.

Parameters

[in]	dblwr_read	true of double write recovery in progress
[in,out]	src	Data read from disk, decompressed data will be copied to this page
[in,out]	dst	Scratch area to use for decompression or nullptr.
[in]	dst_len	If dst is valid, then size of the scratch area in bytes

Returns

DB_SUCCESS or error code

os_file_delete_func()

bool os_file_delete_func

(

const char *

name

)

Deletes a file.

The file has to be closed before calling this.

Parameters

[in]

name

file path as a null-terminated string

Returns

true if success

os_file_delete_if_exists_func()

bool os_file_delete_if_exists_func	(	const char *	name,
		bool *	exist
	)

Deletes a file if it exists.

The file has to be closed before calling this.

Parameters

[in]	name	file path as a null-terminated string
[out]	exist	indicate if file pre-exist

Returns

true if success

os_file_encrypt_page()

file::Block * os_file_encrypt_page	(	const IORequest &	type,
		void *&	buf,
		ulint	n
	)

Encrypt a page content when write it to disk.

Parameters

[in]	type	IO flags
[out]	buf	buffer to read or write
[in]	n	number of bytes to read/write, starting from offset

Returns

pointer to the encrypted page

os_file_exists()

bool os_file_exists

(

const char *

path

)

Check the existence and usefulness of a given path.

Parameters

[in]

path

path name

Return values

true	if the path exists and can be used
false	if the path does not exist or if the path is unusable to get to a possibly existing file or directory.

os_file_flush_func()

bool os_file_flush_func

(

os_file_t

file

)

NOTE! Use the corresponding macro os_file_flush(), not directly this function! Flushes the write buffers of a given file to the disk.

Parameters

[in]

file

handle to a file

Returns

true if success

os_file_get_last_error()

ulint os_file_get_last_error

(

bool

report_all_errors

)

Retrieves the last error number if an error occurs in a file io function.

The number should be retrieved before any other OS calls (because they may overwrite the error number). If the number is not known to this program, the OS error number + 100 is returned.

Parameters

[in]

report_all_errors

true if we want an error message printed for all errors

Returns

error number, or OS error number + 100

os_file_get_size() [1/2]

os_file_size_t os_file_get_size

(

const char *

filename

)

Gets a file size.

Parameters

[in]

filename

Full path to the filename to check

Returns

file size if OK, else set m_total_size to ~0 and m_alloc_size to errno.

os_file_get_size() [2/2]

os_offset_t os_file_get_size

(

pfs_os_file_t

file

)

Gets a file size.

Parameters

[in]

file

Handle to a file

Returns

file size, or (os_offset_t) -1 on failure

os_file_get_status()

dberr_t os_file_get_status	(	const char *	path,
		os_file_stat_t *	stat_info,
		bool	check_rw_perm,
		bool	read_only
	)

This function returns information about the specified file.

Parameters

[in]	path	pathname of the file
[out]	stat_info	information of a file in a directory
[in]	check_rw_perm	for testing whether the file can be opened in RW mode
[in]	read_only	true if file is opened in read-only mode

Returns

DB_SUCCESS if all OK

os_file_original_page_size()

ulint os_file_original_page_size

(

const byte *

buf

)

If it is a compressed page return the original page data + footer size.

Parameters

[in]

buf

Buffer to check, must include header + 10 bytes

Returns

ULINT_UNDEFINED if the page is not a compressed page or length of the original data + footer if it is a compressed page

os_file_punch_hole()

dberr_t os_file_punch_hole	(	os_file_t	fh,
		os_offset_t	off,
		os_offset_t	len
	)

Free storage space associated with a section of the file.

Parameters

[in]	fh	Open file handle
[in]	off	Starting offset (SEEK_SET)
[in]	len	Size of the hole

Returns

DB_SUCCESS or error code

os_file_read_first_page_func()

dberr_t os_file_read_first_page_func	(	IORequest &	type,
		const char *	file_name,
		os_file_t	file,
		void *	buf,
		ulint	n
	)

NOTE! Use the corresponding macro os_file_read_first_page(), not directly this function! Requests a synchronous read operation of page 0 of IBD file.

Parameters

[in]	type	IO request context
[in]	file_name	file name
[in]	file	Open file handle
[out]	buf	buffer where to read
[in]	n	number of bytes to read

Returns

DB_SUCCESS if request was successful, DB_IO_ERROR on failure

os_file_read_func()

dberr_t os_file_read_func	(	IORequest &	type,
		const char *	file_name,
		os_file_t	file,
		void *	buf,
		os_offset_t	offset,
		ulint	n
	)

NOTE! Use the corresponding macro os_file_read_first_page(), not directly this function! Requests a synchronous read operation of page 0 of IBD file.

Parameters

[in]	type	IO request context
[in]	file_name	file name
[in]	file	Open file handle
[out]	buf	buffer where to read
[in]	offset	file offset where to read
[in]	n	number of bytes to read

Returns

DB_SUCCESS if request was successful, DB_IO_ERROR on failure

os_file_read_no_error_handling_func()

dberr_t os_file_read_no_error_handling_func	(	IORequest &	type,
		const char *	file_name,
		os_file_t	file,
		void *	buf,
		os_offset_t	offset,
		ulint	n,
		ulint *	o
	)

NOTE! Use the corresponding macro os_file_read_no_error_handling(), not directly this function! Requests a synchronous positioned read operation.

This function does not do any error handling. In case of error it returns false.

Parameters

[in]	type	IO request context
[in]	file_name	file name
[in]	file	Open file handle
[out]	buf	buffer where to read
[in]	offset	file offset where to read
[in]	n	number of bytes to read
[out]	o	number of bytes actually read

Returns

DB_SUCCESS or error code

os_file_read_string()

void os_file_read_string	(	FILE *	file,
		char *	str,
		ulint	size
	)

Rewind file to its start, read at most size - 1 bytes from it to str, and NUL-terminate str.

All errors are silently ignored. This function is mostly meant to be used with temporary files.

Parameters

[in,out]	file	File to read from
[in,out]	str	Buffer where to read
[in]	size	Size of buffer

os_file_rename_func()

bool os_file_rename_func	(	const char *	oldpath,
		const char *	newpath
	)

NOTE! Use the corresponding macro os_file_rename(), not directly this function! Renames a file (can also move it to another directory).

It is safest that the file is closed before calling this function.

Parameters

[in]	oldpath	old file path as a null-terminated string
[in]	newpath	new file path

Returns

true if success

os_file_scan_directory()

bool os_file_scan_directory	(	const char *	path,
		os_dir_cbk_t	scan_cbk,
		bool	is_drop
	)

This function scans the contents of a directory and invokes the callback for each entry.

Parameters

[in]	path	directory name as null-terminated string
[in]	scan_cbk	use callback to be called for each entry
[in]	is_drop	attempt to drop the directory after scan

Returns

true if call succeeds, false on error

os_file_seek()

bool os_file_seek	(	const char *	pathname,
		os_file_t	file,
		os_offset_t	offset
	)

Set read/write position of a file handle to specific offset.

Parameters

[in]	pathname	file path
[in]	file	file handle
[in]	offset	read/write offset

Returns

true if success

os_file_set_eof()

bool os_file_set_eof

(

FILE *

file

)

Truncates a file at its current position.

Parameters

[in,out]

file

file to be truncated

Returns

true if success in: file to be truncated

true if success

Parameters

file	in: file to be truncated

os_file_set_nocache()

void os_file_set_nocache	(	int	fd,
		const char *	file_name,
		const char *	operation_name
	)

Tries to disable OS caching on an opened file descriptor.

Parameters

[in]	fd	file descriptor to alter
[in]	file_name	file name, used in the diagnostic message
[in]	operation_name	"open" or "create"; used in the diagnostic message

os_file_set_size()

bool os_file_set_size	(	const char *	name,
		pfs_os_file_t	file,
		os_offset_t	offset,
		os_offset_t	size,
		bool	flush
	)

Write the specified number of zeros to a file from specific offset.

Parameters

[in]	name	name of the file or path as a null-terminated string
[in]	file	handle to a file
[in]	offset	file offset
[in]	size	file size
[in]	flush	flush file content to disk

Returns

true if success

os_file_set_size_fast()

bool os_file_set_size_fast	(	const char *	name,
		pfs_os_file_t	file,
		os_offset_t	offset,
		os_offset_t	size,
		bool	flush
	)

Allocate a block to file using fallocate from the given offset if fallocate is supported.

Falls back to the old slower method of writing zeros otherwise.

Parameters

[in]	name	name of the file
[in]	file	handle to the file
[in]	offset	file offset
[in]	size	file size
[in]	flush	flush file content to disk

Returns

true if success

os_file_set_umask()

void os_file_set_umask

(

mode_t

umask

)

Set the global file create umask.

This value is to be set once, at startup and never modified.

Parameters

[in]

umask

The umask to use for all InnoDB file creation.

os_file_status()

bool os_file_status	(	const char *	path,
		bool *	exists,
		os_file_type_t *	type
	)

Check the existence and type of a given path.

Parameters

[in]	path	pathname of the file
[out]	exists	true if file exists
[out]	type	type of the file (if it exists)

Returns

true if call succeeded

os_file_truncate()

bool os_file_truncate	(	const char *	pathname,
		pfs_os_file_t	file,
		os_offset_t	size
	)

Truncates a file to a specified size in bytes.

Do nothing if the size to preserve is greater or equal to the current size of the file.

Parameters

[in]	pathname	file path
[in]	file	file to be truncated
[in]	size	size to preserve in bytes

Returns

true if success

os_file_write_func()

dberr_t os_file_write_func	(	IORequest &	type,
		const char *	name,
		os_file_t	file,
		const void *	buf,
		os_offset_t	offset,
		ulint	n
	)

NOTE! Use the corresponding macro os_file_write(), not directly this function! Requests a synchronous write operation.

Parameters

[in,out]	type	IO request context
[in]	name	name of the file or path as a null-terminated string
[in]	file	Open file handle
[out]	buf	buffer where to read
[in]	offset	file offset where to read
[in]	n	number of bytes to read

Returns

DB_SUCCESS if request was successful

os_file_write_retry()

dberr_t os_file_write_retry	(	IORequest &	type,
		const char *	name,
		pfs_os_file_t	file,
		const void *	buf,
		os_offset_t	offset,
		ulint	n
	)

This is a wrapper function for the os_file_write() function call.

The purpose of this wrapper function is to retry on i/o error. On I/O error (perhaps because of disk full situation) keep retrying the write operation till it succeeds.

Parameters

[in]	type	IO flags
[in]	name	name of the file or path as a null-terminated string
[in]	file	handle to an open file
[out]	buf	buffer from which to write
[in]	offset	file offset from the start where to read
[in]	n	number of bytes to read, starting from offset

Returns

DB_SUCCESS if request was successful, false if fail

os_file_write_zeros()

dberr_t os_file_write_zeros	(	pfs_os_file_t	file,
		const char *	name,
		ulint	page_size,
		os_offset_t	start,
		ulint	len
	)

Fill the pages with NULs.

Parameters

[in]	file	File handle
[in]	name	File name
[in]	page_size	physical page size
[in]	start	Offset from the start of the file in bytes
[in]	len	Length in bytes

Returns

DB_SUCCESS or error code

os_free_block()

void os_free_block ( file::Block *  block )

noexcept

Free a page after sync IO.

Parameters

[in,out]

block

The block to free/release

os_get_free_space()

dberr_t os_get_free_space	(	const char *	path,
		uint64_t &	free_space
	)

Get available free space on disk.

Parameters

[in]	path	pathname of a directory or file in disk
[out]	free_space	free space available in bytes

Returns

DB_SUCCESS if all OK

os_is_o_direct_supported()

bool os_is_o_direct_supported

(

)

Determine if O_DIRECT is supported.

Return values

true	if O_DIRECT is supported.
false	if O_DIRECT is not supported.

os_is_sparse_file_supported()

bool os_is_sparse_file_supported

(

pfs_os_file_t

fh

)

Check if the file system supports sparse files.

Warning: On POSIX systems we try and punch a hole from offset 0 to the system configured page size. This should only be called on an empty file.

Note: On Windows we use the name and on Unices we use the file handle.

Parameters

[in]

fh

File handle for the file - if opened

Returns

true if the file system supports sparse files

pfs_os_aio_func()

static dberr_t pfs_os_aio_func ( IORequest &  type, AIO_mode  mode, const char *  name, pfs_os_file_t  file, void *  buf, os_offset_t  offset, ulint  n, bool  read_only, fil_node_t *  m1, void *  m2, ut::Location  location  )

inlinestatic

NOTE! Please use the corresponding macro os_aio(), not directly this function! Performance schema wrapper function of os_aio() which requests an asynchronous I/O operation.

Parameters

[in]	type	IO request context
[in]	mode	IO mode
[in]	name	Name of the file or path as NUL terminated string
[in]	file	Open file handle
[out]	buf	buffer where to read
[in]	offset	file offset where to read
[in]	n	how many bytes to read or write; this must not cross a file boundary; in AIO this must be a block size multiple
[in]	read_only	if true read only mode checks are enforced
[in,out]	m1	Message for the AIO handler, (can be used to identify a completed AIO operation); ignored if mode is OS_AIO_SYNC
[in,out]	m2	message for the AIO handler (can be used to identify a completed AIO operation); ignored if mode is OS_AIO_SYNC
[in]	location	location where func invoked

Returns

DB_SUCCESS if request was queued successfully, false if fail

pfs_os_file_close_func()

static bool pfs_os_file_close_func ( pfs_os_file_t  file, ut::Location  src_location  )

inlinestatic

NOTE! Please use the corresponding macro os_file_close(), not directly this function! A performance schema instrumented wrapper function for os_file_close().

Parameters

[in]	file	handle to a file
[in]	src_location	location where func invoked

Returns

true if success

pfs_os_file_copy_func()

static dberr_t pfs_os_file_copy_func ( pfs_os_file_t  src, os_offset_t  src_offset, pfs_os_file_t  dest, os_offset_t  dest_offset, uint  size, ut::Location  src_location  )

inlinestatic

copy data from one file to another file.

Data is read/written at current file offset.

Parameters

[in]	src	file handle to copy from
[in]	src_offset	offset to copy from
[in]	dest	file handle to copy to
[in]	dest_offset	offset to copy to
[in]	size	number of bytes to copy
[in]	src_location	location where func invoked

Returns

DB_SUCCESS if successful

pfs_os_file_create_func()

static pfs_os_file_t pfs_os_file_create_func ( mysql_pfs_key_t  key, const char *  name, ulint  create_mode, ulint  purpose, bool  read_only, bool *  success, ut::Location  src_location  )

inlinestatic

NOTE! Please use the corresponding macro os_file_create(), not directly this function! A performance schema wrapper function for os_file_create().

Add instrumentation to monitor file creation/open.

Parameters

[in]	key	Performance Schema Key
[in]	name	name of the file or path as a null-terminated string
[in]	create_mode	create mode
[in]	purpose	OS_DATA_FILE, OS_LOG_FILE etc.
[in]	read_only	if true read only mode checks are enforced
[out]	success	true if succeeded
[in]	src_location	location where func invoked

Returns

own: handle to the file, not defined if error, error number can be retrieved with os_file_get_last_error

pfs_os_file_create_simple_no_error_handling_func()

static pfs_os_file_t pfs_os_file_create_simple_no_error_handling_func ( mysql_pfs_key_t  key, const char *  name, ulint  create_mode, ulint  access_type, bool  read_only, mode_t  umask, bool *  success, ut::Location  src_location  )

inlinestatic

Clang on Windows warns about umask not found.

NOTE! Please use the corresponding macro os_file_create_simple_no_error_handling(), not directly this function! A performance schema instrumented wrapper function for os_file_create_simple_no_error_handling(). Add instrumentation to monitor file creation/open.

Parameters

[in]	key	Performance Schema Key
[in]	name	name of the file or path as a null-terminated string
[in]	create_mode	create mode
[in]	access_type	OS_FILE_READ_ONLY, OS_FILE_READ_WRITE, or OS_FILE_READ_ALLOW_DELETE; the last option is used by a backup program reading the file
[in]	read_only	if true read only mode checks are enforced
[in]	umask	UNIX access permission to be set when creating a file. Use os_umask_default to use global default umask.
[out]	success	true if succeeded
[in]	src_location	location where func invoked

Returns

own: handle to the file, not defined if error, error number can be retrieved with os_file_get_last_error

pfs_os_file_delete_func()

static bool pfs_os_file_delete_func ( mysql_pfs_key_t  key, const char *  name, ut::Location  src_location  )

inlinestatic

NOTE! Please use the corresponding macro os_file_delete(), not directly this function! This is the performance schema instrumented wrapper function for os_file_delete()

Parameters

[in]	key	Performance Schema Key
[in]	name	old file path as a null-terminated string
[in]	src_location	location where func invoked

Returns

true if success

pfs_os_file_delete_if_exists_func()

static bool pfs_os_file_delete_if_exists_func ( mysql_pfs_key_t  key, const char *  name, bool *  exist, ut::Location  src_location  )

inlinestatic

NOTE! Please use the corresponding macro os_file_delete_if_exists(), not directly this function! This is the performance schema instrumented wrapper function for os_file_delete_if_exists()

Parameters

[in]	key	Performance Schema Key
[in]	name	old file path as a null-terminated string
[in]	exist	indicate if file pre-exist
[in]	src_location	location where func invoked

Returns

true if success

pfs_os_file_flush_func()

static bool pfs_os_file_flush_func ( pfs_os_file_t  file, ut::Location  src_location  )

inlinestatic

NOTE! Please use the corresponding macro os_file_flush(), not directly this function! This is the performance schema instrumented wrapper function for os_file_flush() which flushes the write buffers of a given file to the disk.

Flushes the write buffers of a given file to the disk.

Parameters

[in]	file	Open file handle
[in]	src_location	location where func invoked

Returns

true if success

pfs_os_file_read_first_page_func()

static dberr_t pfs_os_file_read_first_page_func ( IORequest &  type, const char *  file_name, pfs_os_file_t  file, void *  buf, ulint  n, ut::Location  src_location  )

inlinestatic

NOTE! Please use the corresponding macro os_file_read_first_page(), not directly this function! This is the performance schema instrumented wrapper function for os_file_read_first_page() which requests a synchronous read operation of page 0 of IBD file.

Parameters

[in,out]	type	IO request context
[in]	file_name	file name
[in]	file	Open file handle
[out]	buf	buffer where to read
[in]	n	number of bytes to read
[in]	src_location	location where func invoked

Returns

DB_SUCCESS if request was successful

pfs_os_file_read_func()

static dberr_t pfs_os_file_read_func ( IORequest &  type, const char *  file_name, pfs_os_file_t  file, void *  buf, os_offset_t  offset, ulint  n, ut::Location  src_location  )

inlinestatic

NOTE! Please use the corresponding macro os_file_read(), not directly this function! This is the performance schema instrumented wrapper function for os_file_read() which requests a synchronous read operation.

Parameters

[in,out]	type	IO request context
[in]	file_name	file name
[in]	file	Open file handle
[out]	buf	buffer where to read
[in]	offset	file offset where to read
[in]	n	number of bytes to read
[in]	src_location	location where func invoked

Returns

DB_SUCCESS if request was successful

pfs_os_file_read_no_error_handling_func()

static dberr_t pfs_os_file_read_no_error_handling_func ( IORequest &  type, const char *  file_name, pfs_os_file_t  file, void *  buf, os_offset_t  offset, ulint  n, ulint *  o, ut::Location  src_location  )

inlinestatic

NOTE! Please use the corresponding macro os_file_read_no_error_handling(), not directly this function! This is the performance schema instrumented wrapper function for os_file_read_no_error_handling_func() which requests a synchronous read operation.

Parameters

[in,out]	type	IO request context
[in]	file_name	file name
[in]	file	Open file handle
[out]	buf	buffer where to read
[in]	offset	file offset where to read
[in]	n	number of bytes to read
[out]	o	number of bytes actually read
[in]	src_location	location where func invoked

Returns

DB_SUCCESS if request was successful

pfs_os_file_read_no_error_handling_int_fd_func()

static dberr_t pfs_os_file_read_no_error_handling_int_fd_func ( IORequest &  type, const char *  file_name, int  file, void *  buf, os_offset_t  offset, ulint  n, ulint *  o, ut::Location  src_location  )

inlinestatic

NOTE! Please use the corresponding macro os_file_read_no_error_handling_int_fd(), not directly this function! This is the performance schema instrumented wrapper function for os_file_read_no_error_handling_int_fd_func() which requests a synchronous read operation on files with int type descriptors.

Parameters

[in,out]	type	IO request context
[in]	file_name	file name
[in]	file	Open file handle
[out]	buf	buffer where to read
[in]	offset	file offset where to read
[in]	n	number of bytes to read
[out]	o	number of bytes actually read
[in]	src_location	location where func invoked

Returns

DB_SUCCESS if request was successful

pfs_os_file_rename_func()

static bool pfs_os_file_rename_func ( mysql_pfs_key_t  key, const char *  oldpath, const char *  newpath, ut::Location  src_location  )

inlinestatic

NOTE! Please use the corresponding macro os_file_rename(), not directly this function! This is the performance schema instrumented wrapper function for os_file_rename()

Parameters

[in]	key	Performance Schema Key
[in]	oldpath	old file path as a null-terminated string
[in]	newpath	new file path
[in]	src_location	location where func invoked

Returns

true if success

pfs_os_file_write_func()

static dberr_t pfs_os_file_write_func ( IORequest &  type, const char *  name, pfs_os_file_t  file, const void *  buf, os_offset_t  offset, ulint  n, ut::Location  src_location  )

inlinestatic

NOTE! Please use the corresponding macro os_file_write(), not directly this function! This is the performance schema instrumented wrapper function for os_file_write() which requests a synchronous write operation.

Parameters

[in,out]	type	IO request context
[in]	name	Name of the file or path as NUL terminated string
[in]	file	Open file handle
[out]	buf	buffer where to read
[in]	offset	file offset where to read
[in]	n	number of bytes to read
[in]	src_location	location where func invoked

Returns

DB_SUCCESS if request was successful

pfs_os_file_write_int_fd_func()

static dberr_t pfs_os_file_write_int_fd_func ( IORequest &  type, const char *  name, int  file, const void *  buf, os_offset_t  offset, ulint  n, ut::Location  src_location  )

inlinestatic

NOTE! Please use the corresponding macro os_file_write(), not directly this function! This is the performance schema instrumented wrapper function for os_file_write() which requests a synchronous write operation on files with int type descriptors.

Parameters

[in,out]	type	IO request context
[in]	name	Name of the file or path as NUL terminated string
[in]	file	Open file handle
[out]	buf	buffer where to read
[in]	offset	file offset where to read
[in]	n	number of bytes to read
[in]	src_location	location where func invoked

Returns

DB_SUCCESS if request was successful

Variable Documentation

innodb_arch_file_key

mysql_pfs_key_t innodb_arch_file_key

extern

innodb_clone_file_key

mysql_pfs_key_t innodb_clone_file_key

extern

innodb_data_file_key

mysql_pfs_key_t innodb_data_file_key

extern

innodb_dblwr_file_key

mysql_pfs_key_t innodb_dblwr_file_key

extern

innodb_log_file_key

mysql_pfs_key_t innodb_log_file_key

extern

innodb_tablespace_open_file_key

mysql_pfs_key_t innodb_tablespace_open_file_key

extern

innodb_temp_file_key

mysql_pfs_key_t innodb_temp_file_key

extern

NUM_RETRIES_ON_PARTIAL_IO

constexpr size_t NUM_RETRIES_ON_PARTIAL_IO = 10

constexpr

Number of retries for partial I/O's.

OS_AIO_N_PENDING_IOS_PER_THREAD

const ulint OS_AIO_N_PENDING_IOS_PER_THREAD = 32

static

Win NT does not allow more than 64.

OS_BUFFERED_FILE

const ulint OS_BUFFERED_FILE = 103

static

OS_CLONE_DATA_FILE

const ulint OS_CLONE_DATA_FILE = 104

static

OS_CLONE_LOG_FILE

const ulint OS_CLONE_LOG_FILE = 105

static

OS_DATA_FILE

const ulint OS_DATA_FILE = 100

static

Types for file create.

OS_DBLWR_FILE

const ulint OS_DBLWR_FILE = 106

static

OS_FD_CLOSED

constexpr os_fd_t OS_FD_CLOSED = -1

staticconstexpr

OS_FILE_ACCESS_VIOLATION

const ulint OS_FILE_ACCESS_VIOLATION = 81

static

OS_FILE_AIO_INTERRUPTED

const ulint OS_FILE_AIO_INTERRUPTED = 79

static

OS_FILE_AIO_RESOURCES_RESERVED

const ulint OS_FILE_AIO_RESOURCES_RESERVED = 75

static

wait for OS aio resources to become available again

OS_FILE_ALREADY_EXISTS

const ulint OS_FILE_ALREADY_EXISTS = 73

static

OS_FILE_CLOSED

constexpr os_fd_t OS_FILE_CLOSED = OS_FD_CLOSED

staticconstexpr

OS_FILE_DISK_FULL

const ulint OS_FILE_DISK_FULL = 72

static

OS_FILE_ERROR_MAX

const ulint OS_FILE_ERROR_MAX = 100

static

OS_FILE_ERROR_NOT_SPECIFIED

const ulint OS_FILE_ERROR_NOT_SPECIFIED = 77

static

OS_FILE_INSUFFICIENT_RESOURCE

const ulint OS_FILE_INSUFFICIENT_RESOURCE = 78

static

OS_FILE_LOG_BLOCK_SIZE

constexpr uint32_t OS_FILE_LOG_BLOCK_SIZE = 512

constexpr

The next value should be smaller or equal to the smallest sector size used on any disk.

A log block is required to be a portion of disk which is written so that if the start and the end of a block get written to disk, then the whole block gets written. This should be true even in most cases of a crash: if this fails for a log block, then it is equivalent to a media failure in the log.

OS_FILE_MAX_PATH

constexpr uint32_t OS_FILE_MAX_PATH = 4000

constexpr

OS_FILE_NAME_TOO_LONG

const ulint OS_FILE_NAME_TOO_LONG = 82

static

OS_FILE_NOT_FOUND

const ulint OS_FILE_NOT_FOUND = 71

static

Error codes from os_file_get_last_error.

OS_FILE_OPERATION_ABORTED

const ulint OS_FILE_OPERATION_ABORTED = 80

static

OS_FILE_PATH_ERROR

const ulint OS_FILE_PATH_ERROR = 74

static

OS_FILE_READ_ALLOW_DELETE

const ulint OS_FILE_READ_ALLOW_DELETE = 555

static

Used by MySQLBackup.

OS_FILE_READ_ONLY

const ulint OS_FILE_READ_ONLY = 333

static

OS_FILE_READ_WRITE

const ulint OS_FILE_READ_WRITE = 444

static

OS_FILE_SHARING_VIOLATION

const ulint OS_FILE_SHARING_VIOLATION = 76

static

OS_FILE_TOO_MANY_OPENED

const ulint OS_FILE_TOO_MANY_OPENED = 83

static

os_fsync_threshold

unsigned long long os_fsync_threshold

extern

os_has_said_disk_full

bool os_has_said_disk_full

extern

os_innodb_umask_default

constexpr mode_t os_innodb_umask_default = std::numeric_limits<mode_t>::max()

constexpr

A magic constant for the umask parameter that indicates caller wants the os_innodb_umask value to be used.

The os_innodb_umask is a static value, private to this module, and to the file creation methods, so it should not be used directly.

OS_LOG_FILE

const ulint OS_LOG_FILE = 101

static

OS_LOG_FILE_RESIZING

const ulint OS_LOG_FILE_RESIZING = 102

static

os_n_file_reads

ulint os_n_file_reads

extern

os_n_file_writes

ulint os_n_file_writes

extern

os_n_fsyncs

ulint os_n_fsyncs

extern

os_n_pending_reads

std::atomic<ulint> os_n_pending_reads

extern

Number of pending read operations.

os_n_pending_writes

std::atomic<ulint> os_n_pending_writes

extern

Number of pending write operations.