Interface for positional access file implementations. More...
#include <tkrzw_file_pos.h>
Public Types | |
| enum | AccessOption : int32_t { ACCESS_DEFAULT = 0 , ACCESS_DIRECT = 1 << 0 , ACCESS_SYNC = 1 << 1 , ACCESS_PADDING = 1 << 2 , ACCESS_PAGECACHE = 1 << 3 } |
| Enumeration of options for SetAccessStrategy. More... | |
 Public Types inherited from tkrzw::File | |
| enum | OpenOption : int32_t { OPEN_DEFAULT = 0 , OPEN_TRUNCATE = 1 << 0 , OPEN_NO_CREATE = 1 << 1 , OPEN_NO_WAIT = 1 << 2 , OPEN_NO_LOCK = 1 << 3 , OPEN_SYNC_HARD = 1 << 4 } |
| Enumeration of options for Open. More... | |
Public Member Functions | |
| virtual | ~PositionalFile ()=default |
| Destructor. More... | |
| virtual Status | SetHeadBuffer (int64_t size)=0 |
| Sets the head buffer to cache the beginning region of the file. More... | |
| virtual Status | SetAccessStrategy (int64_t block_size, int32_t options)=0 |
| Sets access strategy. More... | |
| virtual int64_t | GetBlockSize () const =0 |
| Gets the block size. More... | |
| virtual bool | IsDirectIO () const =0 |
| Checks whether the access mode is direct I/O. More... | |
| Public Member Functions inherited from tkrzw::File | |
| virtual | ~File ()=default |
| Destructor. More... | |
| virtual Status | Open (const std::string &path, bool writable, int32_t options=OPEN_DEFAULT)=0 |
| Opens a file. More... | |
| virtual Status | Close ()=0 |
| Closes the file. More... | |
| virtual Status | Read (int64_t off, void *buf, size_t size)=0 |
| Reads data. More... | |
| virtual std::string | ReadSimple (int64_t off, size_t size) |
| Reads data, in a simple way. More... | |
| virtual Status | Write (int64_t off, const void *buf, size_t size)=0 |
| Writes data. More... | |
| virtual bool | WriteSimple (int64_t off, std::string_view data) |
| Writes data, in a simple way. More... | |
| virtual Status | Append (const void *buf, size_t size, int64_t *off=nullptr)=0 |
| Appends data at the end of the file. More... | |
| virtual int64_t | AppendSimple (const std::string &data) |
| Appends data at the end of the file, in a simple way. More... | |
| virtual Status | Expand (size_t inc_size, int64_t *old_size=nullptr)=0 |
| Expands the file size without writing data. More... | |
| virtual int64_t | ExpandSimple (size_t inc_size) |
| Expands the file size without writing data, in a simple way. More... | |
| virtual Status | Truncate (int64_t size)=0 |
| Truncates the file. More... | |
| virtual Status | TruncateFakely (int64_t size)=0 |
| Truncate the file fakely. More... | |
| virtual Status | Synchronize (bool hard, int64_t off=0, int64_t size=0)=0 |
| Synchronizes the content of the file to the file system. More... | |
| virtual Status | GetSize (int64_t *size)=0 |
| Gets the size of the file. More... | |
| virtual int64_t | GetSizeSimple () |
| Gets the size of the file, in a simple way. More... | |
| virtual Status | SetAllocationStrategy (int64_t init_size, double inc_factor)=0 |
| Sets allocation strategy. More... | |
| virtual Status | CopyProperties (File *file)=0 |
| Copies internal properties to another file object. More... | |
| virtual Status | GetPath (std::string *path)=0 |
| Gets the path of the file. More... | |
| virtual std::string | GetPathSimple () |
| Gets the path of the file, in a simple way. More... | |
| virtual Status | Rename (const std::string &new_path)=0 |
| Renames the file. More... | |
| virtual Status | DisablePathOperations ()=0 |
| Disables operations related to the path. More... | |
| virtual bool | IsOpen () const =0 |
| Checks whether the file is open. More... | |
| virtual bool | IsMemoryMapping () const =0 |
| Checks whether operations are done by memory mapping. More... | |
| virtual bool | IsAtomic () const =0 |
| Checks whether updating operations are atomic and thread-safe. More... | |
| virtual std::unique_ptr< File > | MakeFile () const =0 |
| Makes a new file object of the same concrete class. More... | |
| const std::type_info & | GetType () const |
| Gets the type information of the actual class. More... | |
Additional Inherited Members | |
| Static Public Attributes inherited from tkrzw::File | |
| static constexpr int64_t | DEFAULT_ALLOC_INIT_SIZE = 1LL << 20 |
| The default value of the initial allocation size. More... | |
| static constexpr double | DEFAULT_ALLOC_INC_FACTOR = 2.0 |
| The default value of the allocation increment factor. More... | |
Detailed Description
Interface for positional access file implementations.
Member Enumeration Documentation
◆ AccessOption
| enum tkrzw::PositionalFile::AccessOption : int32_t |
Enumeration of options for SetAccessStrategy.
Constructor & Destructor Documentation
◆ ~PositionalFile()
|
virtualdefault |
Destructor.
Member Function Documentation
◆ SetHeadBuffer()
|
pure virtual |
Sets the head buffer to cache the beginning region of the file.
- Parameters
-
size The size of the head buffer. If it is not positive, it is not used.
- Returns
- The result status.
This method must be called after the file is opened.
Implemented in tkrzw::PositionalAtomicFile, and tkrzw::PositionalParallelFile.
◆ SetAccessStrategy()
|
pure virtual |
Sets access strategy.
- Parameters
-
block_size The block size to which all blocks should be aligned. It must be a power of two and a multiple of the block size of the underlying file system or device. options Bit-sum options of PositionalFile::AccessOption enums;
- Returns
- The result status.
Implemented in tkrzw::PositionalAtomicFile, and tkrzw::PositionalParallelFile.
◆ GetBlockSize()
|
pure virtual |
Gets the block size.
- Returns
- The block size.
Implemented in tkrzw::PositionalAtomicFile, and tkrzw::PositionalParallelFile.
◆ IsDirectIO()
|
pure virtual |
Checks whether the access mode is direct I/O.
- Returns
- True if the access mode is direct I/O, or false if not.
Implemented in tkrzw::PositionalAtomicFile, and tkrzw::PositionalParallelFile.
