store is sort of working

git-svn-id: https://weed-fs.googlecode.com/svn/trunk@3 282b0af5-e82d-9cf1-ede4-77906d7719d0

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

@@ -0,0 +1,47 @@
+package directory
+
+import (
+	"gob"
+	"os"
+	"log"
+)
+
+type Mapper struct {
+	dir              string
+	fileName         string
+	Virtual2physical map[uint32][]uint32
+}
+
+func NewMapper(dirname string, filename string) (m *Mapper) {
+	m = new(Mapper)
+	m.dir = dirname
+	m.fileName = filename
+	log.Println("Loading virtual to physical:", m.dir, "/", m.fileName)
+	dataFile, e := os.OpenFile(m.dir+string(os.PathSeparator)+m.fileName+".map", os.O_RDONLY, 0644)
+	if e != nil {
+		log.Fatalf("Mapping File Read [ERROR] %s\n", e)
+	} else {
+		m.Virtual2physical = make(map[uint32][]uint32)
+		decoder := gob.NewDecoder(dataFile)
+		decoder.Decode(m.Virtual2physical)
+        dataFile.Close()
+	}
+	return
+}
+func (m *Mapper) Get(vid uint32) []uint32 {
+	return m.Virtual2physical[vid]
+}
+func (m *Mapper) Add(vid uint32, pids ...uint32) {
+	m.Virtual2physical[vid] = append(m.Virtual2physical[vid], pids...)
+}
+func (m *Mapper) Save() {
+	log.Println("Saving virtual to physical:", m.dir, "/", m.fileName)
+	dataFile, e := os.OpenFile(m.dir+string(os.PathSeparator)+m.fileName+".map", os.O_WRONLY, 0644)
+	if e != nil {
+		log.Fatalf("Mapping File Save [ERROR] %s\n", e)
+	}
+	defer dataFile.Close()
+	m.Virtual2physical = make(map[uint32][]uint32)
+	encoder := gob.NewEncoder(dataFile)
+	encoder.Encode(m.Virtual2physical)
+}