Chris Lu
4 years ago
2 changed files with 123 additions and 112 deletions
@ -0,0 +1,123 @@ |
|||||
|
package storage |
||||
|
|
||||
|
import ( |
||||
|
"fmt" |
||||
|
"io" |
||||
|
"time" |
||||
|
|
||||
|
"github.com/chrislusf/seaweedfs/weed/glog" |
||||
|
"github.com/chrislusf/seaweedfs/weed/storage/backend" |
||||
|
"github.com/chrislusf/seaweedfs/weed/storage/needle" |
||||
|
"github.com/chrislusf/seaweedfs/weed/storage/super_block" |
||||
|
. "github.com/chrislusf/seaweedfs/weed/storage/types" |
||||
|
) |
||||
|
|
||||
|
// read fills in Needle content by looking up n.Id from NeedleMapper
|
||||
|
func (v *Volume) readNeedle(n *needle.Needle, readOption *ReadOption) (int, error) { |
||||
|
v.dataFileAccessLock.RLock() |
||||
|
defer v.dataFileAccessLock.RUnlock() |
||||
|
|
||||
|
nv, ok := v.nm.Get(n.Id) |
||||
|
if !ok || nv.Offset.IsZero() { |
||||
|
return -1, ErrorNotFound |
||||
|
} |
||||
|
readSize := nv.Size |
||||
|
if readSize.IsDeleted() { |
||||
|
if readOption != nil && readOption.ReadDeleted && readSize != TombstoneFileSize { |
||||
|
glog.V(3).Infof("reading deleted %s", n.String()) |
||||
|
readSize = -readSize |
||||
|
} else { |
||||
|
return -1, ErrorDeleted |
||||
|
} |
||||
|
} |
||||
|
if readSize == 0 { |
||||
|
return 0, nil |
||||
|
} |
||||
|
err := n.ReadData(v.DataBackend, nv.Offset.ToActualOffset(), readSize, v.Version()) |
||||
|
if err == needle.ErrorSizeMismatch && OffsetSize == 4 { |
||||
|
err = n.ReadData(v.DataBackend, nv.Offset.ToActualOffset()+int64(MaxPossibleVolumeSize), readSize, v.Version()) |
||||
|
} |
||||
|
v.checkReadWriteError(err) |
||||
|
if err != nil { |
||||
|
return 0, err |
||||
|
} |
||||
|
bytesRead := len(n.Data) |
||||
|
if !n.HasTtl() { |
||||
|
return bytesRead, nil |
||||
|
} |
||||
|
ttlMinutes := n.Ttl.Minutes() |
||||
|
if ttlMinutes == 0 { |
||||
|
return bytesRead, nil |
||||
|
} |
||||
|
if !n.HasLastModifiedDate() { |
||||
|
return bytesRead, nil |
||||
|
} |
||||
|
if time.Now().Before(time.Unix(0, int64(n.AppendAtNs)).Add(time.Duration(ttlMinutes) * time.Minute)) { |
||||
|
return bytesRead, nil |
||||
|
} |
||||
|
return -1, ErrorNotFound |
||||
|
} |
||||
|
|
||||
|
type VolumeFileScanner interface { |
||||
|
VisitSuperBlock(super_block.SuperBlock) error |
||||
|
ReadNeedleBody() bool |
||||
|
VisitNeedle(n *needle.Needle, offset int64, needleHeader, needleBody []byte) error |
||||
|
} |
||||
|
|
||||
|
func ScanVolumeFile(dirname string, collection string, id needle.VolumeId, |
||||
|
needleMapKind NeedleMapKind, |
||||
|
volumeFileScanner VolumeFileScanner) (err error) { |
||||
|
var v *Volume |
||||
|
if v, err = loadVolumeWithoutIndex(dirname, collection, id, needleMapKind); err != nil { |
||||
|
return fmt.Errorf("failed to load volume %d: %v", id, err) |
||||
|
} |
||||
|
if err = volumeFileScanner.VisitSuperBlock(v.SuperBlock); err != nil { |
||||
|
return fmt.Errorf("failed to process volume %d super block: %v", id, err) |
||||
|
} |
||||
|
defer v.Close() |
||||
|
|
||||
|
version := v.Version() |
||||
|
|
||||
|
offset := int64(v.SuperBlock.BlockSize()) |
||||
|
|
||||
|
return ScanVolumeFileFrom(version, v.DataBackend, offset, volumeFileScanner) |
||||
|
} |
||||
|
|
||||
|
func ScanVolumeFileFrom(version needle.Version, datBackend backend.BackendStorageFile, offset int64, volumeFileScanner VolumeFileScanner) (err error) { |
||||
|
n, nh, rest, e := needle.ReadNeedleHeader(datBackend, version, offset) |
||||
|
if e != nil { |
||||
|
if e == io.EOF { |
||||
|
return nil |
||||
|
} |
||||
|
return fmt.Errorf("cannot read %s at offset %d: %v", datBackend.Name(), offset, e) |
||||
|
} |
||||
|
for n != nil { |
||||
|
var needleBody []byte |
||||
|
if volumeFileScanner.ReadNeedleBody() { |
||||
|
// println("needle", n.Id.String(), "offset", offset, "size", n.Size, "rest", rest)
|
||||
|
if needleBody, err = n.ReadNeedleBody(datBackend, version, offset+NeedleHeaderSize, rest); err != nil { |
||||
|
glog.V(0).Infof("cannot read needle head [%d, %d) body [%d, %d) body length %d: %v", offset, offset+NeedleHeaderSize, offset+NeedleHeaderSize, offset+NeedleHeaderSize+rest, rest, err) |
||||
|
// err = fmt.Errorf("cannot read needle body: %v", err)
|
||||
|
// return
|
||||
|
} |
||||
|
} |
||||
|
err := volumeFileScanner.VisitNeedle(n, offset, nh, needleBody) |
||||
|
if err == io.EOF { |
||||
|
return nil |
||||
|
} |
||||
|
if err != nil { |
||||
|
glog.V(0).Infof("visit needle error: %v", err) |
||||
|
return fmt.Errorf("visit needle error: %v", err) |
||||
|
} |
||||
|
offset += NeedleHeaderSize + rest |
||||
|
glog.V(4).Infof("==> new entry offset %d", offset) |
||||
|
if n, nh, rest, err = needle.ReadNeedleHeader(datBackend, version, offset); err != nil { |
||||
|
if err == io.EOF { |
||||
|
return nil |
||||
|
} |
||||
|
return fmt.Errorf("cannot read needle header at offset %d: %v", offset, err) |
||||
|
} |
||||
|
glog.V(4).Infof("new entry needle size:%d rest:%d", n.Size, rest) |
||||
|
} |
||||
|
return nil |
||||
|
} |
Write
Preview
Loading…
Cancel
Save
Reference in new issue