seaweedfs/weed/filer/filerstore_hardlink.go
2020-12-18 02:55:00 -08:00

102 lines
2.5 KiB
Go

package filer
import (
"bytes"
"context"
"fmt"
"github.com/chrislusf/seaweedfs/weed/glog"
"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
)
func (fsw *FilerStoreWrapper) handleUpdateToHardLinks(ctx context.Context, entry *Entry) error {
if len(entry.HardLinkId) == 0 {
return nil
}
// handle hard links
if err := fsw.setHardLink(ctx, entry); err != nil {
return fmt.Errorf("setHardLink %d: %v", entry.HardLinkId, err)
}
// check what is existing entry
glog.V(4).Infof("handleUpdateToHardLinks FindEntry %s", entry.FullPath)
existingEntry, err := fsw.getActualStore(entry.FullPath).FindEntry(ctx, entry.FullPath)
if err != nil && err != filer_pb.ErrNotFound {
return fmt.Errorf("update existing entry %s: %v", entry.FullPath, err)
}
// remove old hard link
if err == nil && len(existingEntry.HardLinkId) != 0 && bytes.Compare(existingEntry.HardLinkId, entry.HardLinkId) != 0 {
glog.V(4).Infof("handleUpdateToHardLinks DeleteHardLink %s", entry.FullPath)
if err = fsw.DeleteHardLink(ctx, existingEntry.HardLinkId); err != nil {
return err
}
}
return nil
}
func (fsw *FilerStoreWrapper) setHardLink(ctx context.Context, entry *Entry) error {
if len(entry.HardLinkId) == 0 {
return nil
}
key := entry.HardLinkId
newBlob, encodeErr := entry.EncodeAttributesAndChunks()
if encodeErr != nil {
return encodeErr
}
return fsw.KvPut(ctx, key, newBlob)
}
func (fsw *FilerStoreWrapper) maybeReadHardLink(ctx context.Context, entry *Entry) error {
if len(entry.HardLinkId) == 0 {
return nil
}
key := entry.HardLinkId
glog.V(4).Infof("maybeReadHardLink KvGet %v", key)
value, err := fsw.KvGet(ctx, key)
if err != nil {
glog.Errorf("read %s hardlink %d: %v", entry.FullPath, entry.HardLinkId, err)
return err
}
if err = entry.DecodeAttributesAndChunks(value); err != nil {
glog.Errorf("decode %s hardlink %d: %v", entry.FullPath, entry.HardLinkId, err)
return err
}
return nil
}
func (fsw *FilerStoreWrapper) DeleteHardLink(ctx context.Context, hardLinkId HardLinkId) error {
key := hardLinkId
value, err := fsw.KvGet(ctx, key)
if err == ErrKvNotFound {
return nil
}
if err != nil {
return err
}
entry := &Entry{}
if err = entry.DecodeAttributesAndChunks(value); err != nil {
return err
}
entry.HardLinkCounter--
if entry.HardLinkCounter <= 0 {
glog.V(4).Infof("DeleteHardLink KvDelete %v", key)
return fsw.KvDelete(ctx, key)
}
newBlob, encodeErr := entry.EncodeAttributesAndChunks()
if encodeErr != nil {
return encodeErr
}
glog.V(4).Infof("DeleteHardLink KvPut %v", key)
return fsw.KvPut(ctx, key, newBlob)
}