func (ss *Storageserver) Get(args *storageproto.GetArgs, reply *storageproto.GetReply) error {
if !ss.CheckWithinRange(args.Key) {
reply.Status = storageproto.EWRONGSERVER
lsplog.Vlogf(1, "[Get] The key is given to the wrong server")
return nil
}
if args.WantLease {
ss.modifyingLock.Lock()
if ss.modifying[args.Key] != nil {
reply.Lease.Granted = false
} else {
reply.Lease.Granted = true
ss.leasesLock.Lock()
currentLeaseList := ss.leases[args.Key]
if currentLeaseList == nil {
currentLeaseList = list.New()
}
currentLeaseList.PushBack(&ClientLease{args.LeaseClient, time.Now().Add((storageproto.LEASE_SECONDS + storageproto.LEASE_GUARD_SECONDS) * time.Second)})
ss.leasesLock.Unlock()
}
ss.modifyingLock.Unlock()
}
ss.storageLock.Lock()
if ss.storage[args.Key] == nil {
reply.Status = storageproto.EKEYNOTFOUND
} else {
reply.Value = *ss.storage[args.Key]
reply.Status = storageproto.OK
}
ss.storageLock.Unlock()
return nil
}
/**@brief Get value given a key for storage server
* @param key
* @return value
* @return error
*/
func (ls *Libstore) iGet(key string) (string, error) {
var cli *rpc.Client
var args storageproto.GetArgs = storageproto.GetArgs{key, false, ls.Addr}
var reply storageproto.GetReply
var err error
//try cache first
if tmp, err := ls.Leases.Get(key, &args); err == nil {
reply.Value = tmp.(string)
return reply.Value, nil
}
if (ls.Flags & ALWAYS_LEASE) != 0 {
args.WantLease = true
}
//lsplog.Vlogf(0, "libstore Get %s\n", key)
cli, err = ls.GetServer(key)
if lsplog.CheckReport(1, err) {
return "", err
}
//listen on no port to accept revoke
if ls.Addr == "" {
args.WantLease = false
}
//lsplog.Vlogf(0, "Get args:%v\n", args)
err = cli.Call("StorageRPC.Get", &args, &reply)
if lsplog.CheckReport(1, err) {
return "", err
}
//lsplog.Vlogf(0, "Get reply:%v#!!\n", reply)
//fmt.Printf("Get reply granted:%v#!#\n", reply.Lease.Granted)
if reply.Lease.Granted {
ls.Leases.LeaseGranted(key, reply.Value, reply.Lease)
}
if reply.Status != storageproto.OK {
return "", MakeErr("Get()", reply.Status)
}
return reply.Value, nil
}
func (ss *Storageserver) Get(args *storageproto.GetArgs, reply *storageproto.GetReply) error {
//fmt.Println("called get")
//fmt.Printf("key: %v\n", args.Key)
rightServer := ss.checkServer(args.Key)
if rightServer == false {
//fmt.Println("wrong server Get")
reply.Status = storageproto.EWRONGSERVER
return nil
}
<-ss.leaseMapM
leaseInfo, exists := ss.leaseMap[args.Key]
ss.leaseMapM <- 1
if exists == true {
list := *leaseInfo.ClientKeys
for i := 0; i < len(list); i++ {
if list[i] == args.LeaseClient {
args.WantLease = false
break
}
}
}
if args.WantLease == true {
reply.Lease.Granted = true
reply.Lease.ValidSeconds = storageproto.LEASE_SECONDS
var keys []string
if exists == true {
<-leaseInfo.Mutex
*leaseInfo.ClientKeys = append(*leaseInfo.ClientKeys, args.LeaseClient)
leaseInfo.Mutex <- 1
// fmt.Printf("**GET added %v to %v lease list\n", args.LeaseClient, args.Key)
ss.PrintLeaseMap()
} else {
keys = []string{}
keys = append(keys, args.LeaseClient)
<-ss.leaseMapM
mutex := make(chan int, 1)
mutex <- 1
ss.leaseMap[args.Key] = &LeaseInfo{Mutex: mutex, ClientKeys: &keys}
ss.leaseMapM <- 1
// fmt.Printf("**GET added Lease %v to %v\n", args.LeaseClient, args.Key)
ss.PrintLeaseMap()
}
<-ss.clientLeaseMapM
leaseExpiration := time.Now().Add((storageproto.LEASE_SECONDS + storageproto.LEASE_GUARD_SECONDS) * time.Second).UnixNano()
ss.clientLeaseMap[args.LeaseClient+"@"+args.Key] = leaseExpiration
ss.clientLeaseMapM <- 1
} else {
reply.Lease.Granted = false
reply.Lease.ValidSeconds = 0
}
<-ss.valMapM
val, ok := ss.valMap[args.Key]
if ok != true {
reply.Status = storageproto.EKEYNOTFOUND
reply.Value = ""
} else {
reply.Status = storageproto.OK
reply.Value = val
}
ss.valMapM <- 1
//fmt.Printf("Get val for key %v: %v\n", args.Key, reply.Value)
return nil
}