diff options
Diffstat (limited to 'vendor/github.com/ncruces/go-sqlite3/vfs/memdb')
| -rw-r--r-- | vendor/github.com/ncruces/go-sqlite3/vfs/memdb/memdb.go | 101 |
1 files changed, 48 insertions, 53 deletions
diff --git a/vendor/github.com/ncruces/go-sqlite3/vfs/memdb/memdb.go b/vendor/github.com/ncruces/go-sqlite3/vfs/memdb/memdb.go index b99070496..e304f6d58 100644 --- a/vendor/github.com/ncruces/go-sqlite3/vfs/memdb/memdb.go +++ b/vendor/github.com/ncruces/go-sqlite3/vfs/memdb/memdb.go @@ -2,40 +2,39 @@ package memdb import ( "io" + "strings" "sync" "time" "github.com/ncruces/go-sqlite3" + "github.com/ncruces/go-sqlite3/util/vfsutil" "github.com/ncruces/go-sqlite3/vfs" ) const sectorSize = 65536 -// Ensure sectorSize is a multiple of 64K (the largest page size). -var _ [0]struct{} = [sectorSize & 65535]struct{}{} - type memVFS struct{} func (memVFS) Open(name string, flags vfs.OpenFlag) (vfs.File, vfs.OpenFlag, error) { // For simplicity, we do not support reading or writing data // across "sector" boundaries. - // - // This is not a problem for most SQLite file types: - // - databases, which only do page aligned reads/writes; - // - temp journals, as used by the sorter, which does the same: - // https://github.com/sqlite/sqlite/blob/b74eb0/src/vdbesort.c#L409-L412 - // - // We refuse to open all other file types, - // but returning OPEN_MEMORY means SQLite won't ask us to. - const types = vfs.OPEN_MAIN_DB | vfs.OPEN_TEMP_DB | - vfs.OPEN_TRANSIENT_DB | vfs.OPEN_TEMP_JOURNAL - if flags&types == 0 { + // This is not a problem for SQLite database files. + const databases = vfs.OPEN_MAIN_DB | vfs.OPEN_TEMP_DB | vfs.OPEN_TRANSIENT_DB + + // Temp journals, as used by the sorter, use SliceFile. + if flags&vfs.OPEN_TEMP_JOURNAL != 0 { + return &vfsutil.SliceFile{}, flags | vfs.OPEN_MEMORY, nil + } + + // Refuse to open all other file types. + // Returning OPEN_MEMORY means SQLite won't ask us to. + if flags&databases == 0 { // notest // OPEN_MEMORY return nil, flags, sqlite3.CANTOPEN } // A shared database has a name that begins with "/". - shared := len(name) > 1 && name[0] == '/' + shared := strings.HasPrefix(name, "/") var db *memDB if shared { @@ -76,18 +75,16 @@ func (memVFS) FullPathname(name string) (string, error) { type memDB struct { name string + // +checklocks:lockMtx + waiter *sync.Cond // +checklocks:dataMtx data []*[sectorSize]byte - // +checklocks:dataMtx - size int64 - - // +checklocks:memoryMtx - refs int32 - shared int32 // +checklocks:lockMtx - pending bool // +checklocks:lockMtx - reserved bool // +checklocks:lockMtx - waiter *sync.Cond // +checklocks:lockMtx + size int64 // +checklocks:dataMtx + refs int32 // +checklocks:memoryMtx + shared int32 // +checklocks:lockMtx + pending bool // +checklocks:lockMtx + reserved bool // +checklocks:lockMtx lockMtx sync.Mutex dataMtx sync.RWMutex @@ -129,7 +126,7 @@ func (m *memFile) ReadAt(b []byte, off int64) (n int, err error) { base := off / sectorSize rest := off % sectorSize have := int64(sectorSize) - if base == int64(len(m.data))-1 { + if m.size < off+int64(len(b)) { have = modRoundUp(m.size, sectorSize) } n = copy(b, (*m.data[base])[rest:have]) @@ -150,22 +147,37 @@ func (m *memFile) WriteAt(b []byte, off int64) (n int, err error) { m.data = append(m.data, new([sectorSize]byte)) } n = copy((*m.data[base])[rest:], b) + if size := off + int64(n); size > m.size { + m.size = size + } if n < len(b) { // notest // assume writes are page aligned return n, io.ErrShortWrite } - if size := off + int64(len(b)); size > m.size { - m.size = size - } return n, nil } +func (m *memFile) Size() (int64, error) { + m.dataMtx.RLock() + defer m.dataMtx.RUnlock() + return m.size, nil +} + func (m *memFile) Truncate(size int64) error { m.dataMtx.Lock() defer m.dataMtx.Unlock() return m.truncate(size) } +func (m *memFile) SizeHint(size int64) error { + m.dataMtx.Lock() + defer m.dataMtx.Unlock() + if size > m.size { + return m.truncate(size) + } + return nil +} + // +checklocks:m.dataMtx func (m *memFile) truncate(size int64) error { if size < m.size { @@ -185,16 +197,6 @@ func (m *memFile) truncate(size int64) error { return nil } -func (m *memFile) Sync(flag vfs.SyncFlag) error { - return nil -} - -func (m *memFile) Size() (int64, error) { - m.dataMtx.RLock() - defer m.dataMtx.RUnlock() - return m.size, nil -} - func (m *memFile) Lock(lock vfs.LockLevel) error { if m.lock >= lock { return nil @@ -278,31 +280,24 @@ func (m *memFile) CheckReservedLock() (bool, error) { return m.reserved, nil } -func (m *memFile) SectorSize() int { +func (m *memFile) LockState() vfs.LockLevel { + return m.lock +} + +func (*memFile) Sync(flag vfs.SyncFlag) error { return nil } + +func (*memFile) SectorSize() int { // notest // IOCAP_POWERSAFE_OVERWRITE return sectorSize } -func (m *memFile) DeviceCharacteristics() vfs.DeviceCharacteristic { +func (*memFile) DeviceCharacteristics() vfs.DeviceCharacteristic { return vfs.IOCAP_ATOMIC | vfs.IOCAP_SEQUENTIAL | vfs.IOCAP_SAFE_APPEND | vfs.IOCAP_POWERSAFE_OVERWRITE } -func (m *memFile) SizeHint(size int64) error { - m.dataMtx.Lock() - defer m.dataMtx.Unlock() - if size > m.size { - return m.truncate(size) - } - return nil -} - -func (m *memFile) LockState() vfs.LockLevel { - return m.lock -} - func divRoundUp(a, b int64) int64 { return (a + b - 1) / b } |