correctly deleting a file

correctly setting volume file size limit

git-svn-id: https://weed-fs.googlecode.com/svn/trunk@42 282b0af5-e82d-9cf1-ede4-77906d7719d0

weed-fs/src/pkg/directory/volume_mapping.go

@@ -36,14 +36,14 @@ type Mapper struct {
 	FileIdSequence uint64
 	fileIdCounter  uint64
 
-	volumeSizeLimit uint32
+	volumeSizeLimit uint64
 }
 
 func NewMachine(server, publicUrl string, volumes []storage.VolumeInfo) *Machine {
 	return &Machine{Server: MachineInfo{Url: server, PublicUrl: publicUrl}, Volumes: volumes}
 }
 
-func NewMapper(dirname string, filename string, volumeSizeLimit uint32) (m *Mapper) {
+func NewMapper(dirname string, filename string, volumeSizeLimit uint64) (m *Mapper) {
 	m = &Mapper{dir: dirname, fileName: filename}
 	m.vid2machineId = make(map[uint32]int)
 	m.volumeSizeLimit = volumeSizeLimit
@@ -96,6 +96,7 @@ func (m *Mapper) Get(vid uint32) (*Machine, os.Error) {
 }
 func (m *Mapper) Add(machine Machine) {
 	//check existing machine, linearly
+    log.Println("Adding machine", machine.Server.Url)
 	m.lock.Lock()
 	foundExistingMachineId := -1
 	for index, entry := range m.Machines {
@@ -115,14 +116,13 @@ func (m *Mapper) Add(machine Machine) {
 
 	//add to vid2machineId map, and Writers array
 	for _, v := range machine.Volumes {
-		//log.Println("Setting volume", v.Id, "to", machine.Server.Url)
 		m.vid2machineId[v.Id] = machineId + 1 //use base 1 indexed, to detect not found cases
 	}
-	//setting Writers, copy-on-write because of possible updating
+	//setting Writers, copy-on-write because of possible updating, this needs some future work!
 	var writers []uint32
 	for _, machine_entry := range m.Machines {
 		for _, v := range machine_entry.Volumes {
-			if v.Size < int64(m.volumeSizeLimit) {
+			if uint64(v.Size) < m.volumeSizeLimit {
 				writers = append(writers, v.Id)
 			}
 		}

weed-fs/src/pkg/storage/store.go

@@ -92,7 +92,10 @@ func (s *Store) Close() {
 	}
 }
 func (s *Store) Write(i uint64, n *Needle) uint32 {
-	return s.volumes[i].write(n)
+    return s.volumes[i].write(n)
+}
+func (s *Store) Delete(i uint64, n *Needle) uint32 {
+	return s.volumes[i].delete(n)
 }
 func (s *Store) Read(i uint64, n *Needle) (int, os.Error) {
 	return s.volumes[i].read(n)

weed-fs/src/pkg/storage/volume.go

@@ -9,7 +9,7 @@ import (
 )
 
 const (
-    SuperBlockSize = 8
+	SuperBlockSize = 8
 )
 
 type Volume struct {
@@ -69,6 +69,19 @@ func (v *Volume) write(n *Needle) uint32 {
 	}
 	return ret
 }
+func (v *Volume) delete(n *Needle) uint32 {
+	v.accessLock.Lock()
+	defer v.accessLock.Unlock()
+	nv, ok := v.nm.Get(n.Key)
+	//log.Println("key", n.Key, "volume offset", nv.Offset, "data_size", n.Size, "cached size", nv.Size)
+	if ok {
+		v.nm.Delete(n.Key)
+		v.dataFile.Seek(int64(nv.Offset*8), 0)
+		n.Append(v.dataFile)
+		return nv.Size
+	}
+	return 0
+}
 func (v *Volume) read(n *Needle) (int, os.Error) {
 	v.accessLock.Lock()
 	defer v.accessLock.Unlock()
@@ -79,8 +92,3 @@ func (v *Volume) read(n *Needle) (int, os.Error) {
 	}
 	return -1, os.EOF
 }
-func (v *Volume) delete(n *Needle) {
-    v.accessLock.Lock()
-    defer v.accessLock.Unlock()
-    v.nm.Delete(n.Key)
-}