adding diskvd.go file

src/main/diskvd.go

+package main
+
+//
+// start a diskvd server. it's a member of some replica
+// group, which has other members, and it needs to know
+// how to talk to the members of the shardmaster service.
+// used by ../diskv/test_test.go
+//
+// arguments:
+//   -g groupid
+//   -m masterport1 -m masterport2 ...
+//   -s replicaport1 -s replicaport2 ...
+//   -i my-index-in-server-port-list
+//   -u unreliable
+//   -d directory
+//   -r restart
+
+import "time"
+import "diskv"
+import "os"
+import "fmt"
+import "strconv"
+import "runtime"
+
+func usage() {
+	fmt.Printf("Usage: diskvd -g gid -m master... -s server... -i my-index -d dir\n")
+	os.Exit(1)
+}
+
+func main() {
+	var gid int64 = -1     // my replica group ID
+	masters := []string{}  // ports of shardmasters
+	replicas := []string{} // ports of servers in my replica group
+	me := -1               // my index in replicas[]
+	unreliable := false
+	dir := "" // store persistent data here
+	restart := false
+
+	for i := 1; i+1 < len(os.Args); i += 2 {
+		a0 := os.Args[i]
+		a1 := os.Args[i+1]
+		if a0 == "-g" {
+			gid, _ = strconv.ParseInt(a1, 10, 64)
+		} else if a0 == "-m" {
+			masters = append(masters, a1)
+		} else if a0 == "-s" {
+			replicas = append(replicas, a1)
+		} else if a0 == "-i" {
+			me, _ = strconv.Atoi(a1)
+		} else if a0 == "-u" {
+			unreliable, _ = strconv.ParseBool(a1)
+		} else if a0 == "-d" {
+			dir = a1
+		} else if a0 == "-r" {
+			restart, _ = strconv.ParseBool(a1)
+		} else {
+			usage()
+		}
+	}
+
+	if gid < 0 || me < 0 || len(masters) < 1 || me >= len(replicas) || dir == "" {
+		usage()
+	}
+
+	runtime.GOMAXPROCS(4)
+
+	srv := diskv.StartServer(gid, masters, replicas, me, dir, restart)
+	srv.Setunreliable(unreliable)
+
+	// for safety, force quit after 10 minutes.
+	time.Sleep(10 * 60 * time.Second)
+	mep, _ := os.FindProcess(os.Getpid())
+	mep.Kill()
+}