implemented api handlers

pkg/alloc/alloc.go

@@ -36,22 +36,26 @@ func (a *Alloc) UpdateDB(db *db.DB) {
 	a.Unlock()
 }
 
+func (a *Alloc) cidr(ip net.IP) string {
+	gw := new(net.IPNet)
+	*gw = *a.gateway
+	gw.IP = ip
+	return gw.String()
+}
+
 func (a *Alloc) AllocIP(ctx context.Context, name string) (addr string, err error) {
 	a.Lock()
 	defer a.Unlock()
 	for _, cidr := range a.pool {
 		c := ipaddr.NewCursor([]ipaddr.Prefix{*ipaddr.NewPrefix(cidr)})
 		for pos := c.First(); pos != nil; pos = c.Next() {
-			ip := pos.IP.String()
-			if !a.db.IPExists(ip) {
-				err = a.db.SetIP(ip, name)
+			cidr := a.cidr(pos.IP)
+			if !a.db.IPExists(cidr) {
+				err = a.db.SetIP(cidr, name)
 				if err != nil {
 					return
 				}
-				var gw *net.IPNet
-				*gw = *a.gateway
-				gw.IP = pos.IP
-				addr = gw.String()
+				addr = pos.IP.String()
 				return
 			}
 		}