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package storage
import ( "io" "os"
"github.com/chrislusf/weed-fs/go/glog" "github.com/chrislusf/weed-fs/go/util" )
type NeedleMap struct { indexFile *os.File m CompactMap
mapMetric }
func NewNeedleMap(file *os.File) *NeedleMap { nm := &NeedleMap{ m: NewCompactMap(), indexFile: file, } return nm }
const ( RowsToRead = 1024 )
func LoadNeedleMap(file *os.File) (*NeedleMap, error) { nm := NewNeedleMap(file) e := WalkIndexFile(file, func(key uint64, offset, size uint32) error { if key > nm.MaximumFileKey { nm.MaximumFileKey = key } nm.FileCounter++ nm.FileByteCounter = nm.FileByteCounter + uint64(size) if offset > 0 { oldSize := nm.m.Set(Key(key), offset, size) glog.V(3).Infoln("reading key", key, "offset", offset*NeedlePaddingSize, "size", size, "oldSize", oldSize) if oldSize > 0 { nm.DeletionCounter++ nm.DeletionByteCounter = nm.DeletionByteCounter + uint64(oldSize) } } else { oldSize := nm.m.Delete(Key(key)) glog.V(3).Infoln("removing key", key, "offset", offset*NeedlePaddingSize, "size", size, "oldSize", oldSize) nm.DeletionCounter++ nm.DeletionByteCounter = nm.DeletionByteCounter + uint64(oldSize) } return nil }) glog.V(1).Infoln("max file key:", nm.MaximumFileKey) return nm, e }
// walks through the index file, calls fn function with each key, offset, size
// stops with the error returned by the fn function
func WalkIndexFile(r *os.File, fn func(key uint64, offset, size uint32) error) error { var readerOffset int64 bytes := make([]byte, 16*RowsToRead) count, e := r.ReadAt(bytes, readerOffset) glog.V(3).Infoln("file", r.Name(), "readerOffset", readerOffset, "count", count, "e", e) readerOffset += int64(count) var ( key uint64 offset, size uint32 i int )
for count > 0 && e == nil || e == io.EOF { for i = 0; i+16 <= count; i += 16 { key = util.BytesToUint64(bytes[i : i+8]) offset = util.BytesToUint32(bytes[i+8 : i+12]) size = util.BytesToUint32(bytes[i+12 : i+16]) if e = fn(key, offset, size); e != nil { return e } } if e == io.EOF { return nil } count, e = r.ReadAt(bytes, readerOffset) glog.V(3).Infoln("file", r.Name(), "readerOffset", readerOffset, "count", count, "e", e) readerOffset += int64(count) } return e }
func (nm *NeedleMap) Put(key uint64, offset uint32, size uint32) error { oldSize := nm.m.Set(Key(key), offset, size) nm.logPut(key, oldSize, size) return appendToIndexFile(nm.indexFile, key, offset, size) } func (nm *NeedleMap) Get(key uint64) (element *NeedleValue, ok bool) { element, ok = nm.m.Get(Key(key)) return } func (nm *NeedleMap) Delete(key uint64) error { deletedBytes := nm.m.Delete(Key(key)) nm.logDelete(deletedBytes) return appendToIndexFile(nm.indexFile, key, 0, 0) } func (nm *NeedleMap) Close() { _ = nm.indexFile.Close() } func (nm *NeedleMap) Destroy() error { nm.Close() return os.Remove(nm.indexFile.Name()) } func (nm NeedleMap) ContentSize() uint64 { return nm.FileByteCounter } func (nm NeedleMap) DeletedSize() uint64 { return nm.DeletionByteCounter } func (nm NeedleMap) FileCount() int { return nm.FileCounter } func (nm NeedleMap) DeletedCount() int { return nm.DeletionCounter }
func (nm NeedleMap) MaxFileKey() uint64 { return nm.MaximumFileKey }
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