initial commit

1 files changed, 61 insertions, 0 deletions

diff --git a/pkg/binstruct/l3.go b/pkg/binstruct/l3.go
new file mode 100644
index 0000000..f9fb8b1
--- /dev/null
+++ b/pkg/binstruct/l3.go
@@ -0,0 +1,61 @@
+package binstruct
+
+import (
+	"fmt"
+	"reflect"
+)
+
+var handlerCache = make(map[reflect.Type]handler)
+
+func getHandler(typ reflect.Type) (handler, error) {
+	h, ok := handlerCache[typ]
+	if ok {
+		return h, nil
+	}
+
+	h, err := genHandler(typ)
+	if err != nil {
+		return nil, err
+	}
+	handlerCache[typ] = h
+	return h, nil
+}
+
+func Unmarshal(dat []byte, dst interface{}) error {
+	_dst := reflect.ValueOf(dst)
+	if _dst.Kind() != reflect.Ptr {
+		return fmt.Errorf("not a pointer: %v", _dst.Type())
+	}
+	handler, err := getHandler(_dst.Type().Elem())
+	if err != nil {
+		return err
+	}
+	if int64(len(dat)) < handler.Size() {
+		return fmt.Errorf("need at least %d bytes of data, only have %d",
+			handler.Size(), len(dat))
+	}
+	val := handler.Unmarshal(dat[:handler.Size()])
+	_dst.Elem().Set(reflect.ValueOf(val))
+	return nil
+}
+
+func Marshal(val interface{}) ([]byte, error) {
+	handler, err := getHandler(reflect.TypeOf(val))
+	if err != nil {
+		return nil, err
+	}
+	bs := handler.Marshal(val)
+	if int64(len(bs)) != handler.Size() {
+		return nil, fmt.Errorf("got %d bytes but expected %d bytes",
+			len(bs), handler.Size())
+	}
+	return bs, nil
+}
+
+func Size(val interface{}) (int64, error) {
+	handler, err := getHandler(reflect.TypeOf(val))
+	if err != nil {
+		return 0, err
+	}
+	return handler.Size(), nil
+}