Avoid allocating strings in common message types

command_complete.go

@@ -8,7 +8,7 @@ import (
 )
 
 type CommandComplete struct {
-	CommandTag string
+	CommandTag []byte
 }
 
 func (*CommandComplete) Backend() {}
@@ -19,7 +19,7 @@ func (dst *CommandComplete) Decode(src []byte) error {
 		return &invalidMessageFormatErr{messageType: "CommandComplete"}
 	}
 
-	dst.CommandTag = string(src[:idx])
+	dst.CommandTag = src[:idx]
 
 	return nil
 }
@@ -43,6 +43,6 @@ func (src *CommandComplete) MarshalJSON() ([]byte, error) {
 		CommandTag string
 	}{
 		Type:       "CommandComplete",
-		CommandTag: src.CommandTag,
+		CommandTag: string(src.CommandTag),
 	})
 }

row_description.go

@@ -14,7 +14,7 @@ const (
 )
 
 type FieldDescription struct {
-	Name                 string
+	Name                 []byte
 	TableOID             uint32
 	TableAttributeNumber uint16
 	DataTypeOID          uint32
@@ -45,7 +45,7 @@ func (dst *RowDescription) Decode(src []byte) error {
 		if err != nil {
 			return err
 		}
-		fd.Name = string(bName[:len(bName)-1])
+		fd.Name = bName[:len(bName)-1]
 
 		// Since buf.Next() doesn't return an error if we hit the end of the buffer
 		// check Len ahead of time