add open release, refactor

weed/mount/filehandle_map.go

@@ -0,0 +1,79 @@
+package mount
+
+import (
+	"github.com/chrislusf/seaweedfs/weed/pb/filer_pb"
+	"sync"
+)
+
+type FileHandleId uint64
+
+type FileHandleToInode struct {
+	sync.RWMutex
+	nextFh   FileHandleId
+	inode2fh map[uint64]*FileHandle
+	fh2inode map[FileHandleId]uint64
+}
+type FileHandle struct {
+	fh      FileHandleId
+	counter int64
+	entry   *filer_pb.Entry
+	inode   uint64
+}
+
+func NewFileHandleToInode() *FileHandleToInode {
+	return &FileHandleToInode{
+		inode2fh: make(map[uint64]*FileHandle),
+		fh2inode: make(map[FileHandleId]uint64),
+		nextFh:   0,
+	}
+}
+
+func (i *FileHandleToInode) GetFileHandle(inode uint64) *FileHandle {
+	i.Lock()
+	defer i.Unlock()
+	fh, found := i.inode2fh[inode]
+	if !found {
+		fh = &FileHandle{
+			fh:      i.nextFh,
+			counter: 1,
+			inode:   inode,
+		}
+		i.nextFh++
+		i.inode2fh[inode] = fh
+		i.fh2inode[fh.fh] = inode
+	} else {
+		fh.counter++
+	}
+	return fh
+}
+
+func (i *FileHandleToInode) ReleaseByInode(inode uint64) {
+	i.Lock()
+	defer i.Unlock()
+	fh, found := i.inode2fh[inode]
+	if found {
+		fh.counter--
+		if fh.counter <= 0 {
+			delete(i.inode2fh, inode)
+			delete(i.fh2inode, fh.fh)
+		}
+	}
+}
+func (i *FileHandleToInode) ReleaseByHandle(fh FileHandleId) {
+	i.Lock()
+	defer i.Unlock()
+	inode, found := i.fh2inode[fh]
+	if found {
+		fhHandle, fhFound := i.inode2fh[inode]
+		if !fhFound {
+			delete(i.fh2inode, fh)
+		} else {
+			fhHandle.counter--
+			if fhHandle.counter <= 0 {
+				delete(i.inode2fh, inode)
+				delete(i.fh2inode, fhHandle.fh)
+			}
+		}
+
+	}
+}