update config parsing

pkg/registry/hosts.go

@@ -0,0 +1,51 @@
+package registry
+
+import (
+	"net"
+	"sync"
+
+	"github.com/go-gost/gost/pkg/hosts"
+)
+
+var (
+	hostsReg = &hostsRegistry{}
+)
+
+func Hosts() *hostsRegistry {
+	return hostsReg
+}
+
+type hostsRegistry struct {
+	m sync.Map
+}
+
+func (r *hostsRegistry) Register(name string, hosts hosts.HostMapper) error {
+	if _, loaded := r.m.LoadOrStore(name, hosts); loaded {
+		return ErrDup
+	}
+
+	return nil
+}
+
+func (r *hostsRegistry) Unregister(name string) {
+	r.m.Delete(name)
+}
+
+func (r *hostsRegistry) Get(name string) hosts.HostMapper {
+	if _, ok := r.m.Load(name); !ok {
+		return nil
+	}
+	return &hostsWrapper{name: name}
+}
+
+type hostsWrapper struct {
+	name string
+}
+
+func (w *hostsWrapper) Lookup(network, host string) ([]net.IP, bool) {
+	v := Hosts().Get(w.name)
+	if v == nil {
+		return nil, false
+	}
+	return v.Lookup(network, host)
+}