gotosocial/vendor/github.com/ncruces/go-sqlite3/vfs/api.go
2024-10-25 16:09:18 +00:00

194 lines
5.3 KiB
Go

// Package vfs wraps the C SQLite VFS API.
package vfs
import (
"context"
"io"
"github.com/tetratelabs/wazero/api"
)
// A VFS defines the interface between the SQLite core and the underlying operating system.
//
// Use sqlite3.ErrorCode or sqlite3.ExtendedErrorCode to return specific error codes to SQLite.
//
// https://sqlite.org/c3ref/vfs.html
type VFS interface {
Open(name string, flags OpenFlag) (File, OpenFlag, error)
Delete(name string, syncDir bool) error
Access(name string, flags AccessFlag) (bool, error)
FullPathname(name string) (string, error)
}
// VFSFilename extends VFS with the ability to use Filename
// objects for opening files.
//
// https://sqlite.org/c3ref/filename.html
type VFSFilename interface {
VFS
OpenFilename(name *Filename, flags OpenFlag) (File, OpenFlag, error)
}
// A File represents an open file in the OS interface layer.
//
// Use sqlite3.ErrorCode or sqlite3.ExtendedErrorCode to return specific error codes to SQLite.
// In particular, sqlite3.BUSY is necessary to correctly implement lock methods.
//
// https://sqlite.org/c3ref/io_methods.html
type File interface {
Close() error
ReadAt(p []byte, off int64) (n int, err error)
WriteAt(p []byte, off int64) (n int, err error)
Truncate(size int64) error
Sync(flags SyncFlag) error
Size() (int64, error)
Lock(lock LockLevel) error
Unlock(lock LockLevel) error
CheckReservedLock() (bool, error)
SectorSize() int
DeviceCharacteristics() DeviceCharacteristic
}
// FileUnwrap should be implemented by a File
// that wraps another File implementation.
type FileUnwrap interface {
File
Unwrap() File
}
// FileLockState extends File to implement the
// SQLITE_FCNTL_LOCKSTATE file control opcode.
//
// https://sqlite.org/c3ref/c_fcntl_begin_atomic_write.html#sqlitefcntllockstate
type FileLockState interface {
File
LockState() LockLevel
}
// FilePersistentWAL extends File to implement the
// SQLITE_FCNTL_PERSIST_WAL file control opcode.
//
// https://sqlite.org/c3ref/c_fcntl_begin_atomic_write.html#sqlitefcntlpersistwal
type FilePersistentWAL interface {
File
PersistentWAL() bool
SetPersistentWAL(bool)
}
// FilePowersafeOverwrite extends File to implement the
// SQLITE_FCNTL_POWERSAFE_OVERWRITE file control opcode.
//
// https://sqlite.org/c3ref/c_fcntl_begin_atomic_write.html#sqlitefcntlpowersafeoverwrite
type FilePowersafeOverwrite interface {
File
PowersafeOverwrite() bool
SetPowersafeOverwrite(bool)
}
// FileChunkSize extends File to implement the
// SQLITE_FCNTL_CHUNK_SIZE file control opcode.
//
// https://sqlite.org/c3ref/c_fcntl_begin_atomic_write.html#sqlitefcntlchunksize
type FileChunkSize interface {
File
ChunkSize(size int)
}
// FileSizeHint extends File to implement the
// SQLITE_FCNTL_SIZE_HINT file control opcode.
//
// https://sqlite.org/c3ref/c_fcntl_begin_atomic_write.html#sqlitefcntlsizehint
type FileSizeHint interface {
File
SizeHint(size int64) error
}
// FileHasMoved extends File to implement the
// SQLITE_FCNTL_HAS_MOVED file control opcode.
//
// https://sqlite.org/c3ref/c_fcntl_begin_atomic_write.html#sqlitefcntlhasmoved
type FileHasMoved interface {
File
HasMoved() (bool, error)
}
// FileOverwrite extends File to implement the
// SQLITE_FCNTL_OVERWRITE file control opcode.
//
// https://sqlite.org/c3ref/c_fcntl_begin_atomic_write.html#sqlitefcntloverwrite
type FileOverwrite interface {
File
Overwrite() error
}
// FileCommitPhaseTwo extends File to implement the
// SQLITE_FCNTL_COMMIT_PHASETWO file control opcode.
//
// https://sqlite.org/c3ref/c_fcntl_begin_atomic_write.html#sqlitefcntlcommitphasetwo
type FileCommitPhaseTwo interface {
File
CommitPhaseTwo() error
}
// FileBatchAtomicWrite extends File to implement the
// SQLITE_FCNTL_BEGIN_ATOMIC_WRITE, SQLITE_FCNTL_COMMIT_ATOMIC_WRITE
// and SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE file control opcodes.
//
// https://sqlite.org/c3ref/c_fcntl_begin_atomic_write.html#sqlitefcntlbeginatomicwrite
type FileBatchAtomicWrite interface {
File
BeginAtomicWrite() error
CommitAtomicWrite() error
RollbackAtomicWrite() error
}
// FileCheckpoint extends File to implement the
// SQLITE_FCNTL_CKPT_START and SQLITE_FCNTL_CKPT_DONE
// file control opcodes.
//
// https://sqlite.org/c3ref/c_fcntl_begin_atomic_write.html#sqlitefcntlckptstart
type FileCheckpoint interface {
File
CheckpointStart()
CheckpointDone()
}
// FilePragma extends File to implement the
// SQLITE_FCNTL_PRAGMA file control opcode.
//
// https://sqlite.org/c3ref/c_fcntl_begin_atomic_write.html#sqlitefcntlpragma
type FilePragma interface {
File
Pragma(name, value string) (string, error)
}
// FileSharedMemory extends File to possibly implement
// shared-memory for the WAL-index.
// The same shared-memory instance must be returned
// for the entire life of the file.
// It's OK for SharedMemory to return nil.
type FileSharedMemory interface {
File
SharedMemory() SharedMemory
}
// SharedMemory is a shared-memory WAL-index implementation.
// Use [NewSharedMemory] to create a shared-memory.
type SharedMemory interface {
shmMap(context.Context, api.Module, int32, int32, bool) (uint32, _ErrorCode)
shmLock(int32, int32, _ShmFlag) _ErrorCode
shmUnmap(bool)
shmBarrier()
io.Closer
}
type blockingSharedMemory interface {
SharedMemory
shmEnableBlocking(block bool)
}
type fileControl interface {
File
fileControl(ctx context.Context, mod api.Module, op _FcntlOpcode, pArg uint32) _ErrorCode
}