use stack allocated byte array

common/serial/serial.go

@@ -3,34 +3,42 @@ package serial
 import (
 	"encoding/binary"
 	"io"
+	"unsafe"
+
+	"v2ray.com/core/common/stack"
 )
 
 // ReadUint16 reads first two bytes from the reader, and then coverts them to an uint16 value.
 func ReadUint16(reader io.Reader) (uint16, error) {
-	var b [2]byte
-	if _, err := io.ReadFull(reader, b[:]); err != nil {
+	var b stack.TwoBytes
+	s := b[:]
+	p := uintptr(unsafe.Pointer(&s))
+	v := (*[]byte)(unsafe.Pointer(p))
+
+	if _, err := io.ReadFull(reader, *v); err != nil {
 		return 0, err
 	}
-	return binary.BigEndian.Uint16(b[:]), nil
+	return binary.BigEndian.Uint16(*v), nil
 }
 
 // WriteUint16 writes an uint16 value into writer.
 func WriteUint16(writer io.Writer, value uint16) (int, error) {
-	var b [2]byte
-	binary.BigEndian.PutUint16(b[:], value)
-	return writer.Write(b[:])
-}
+	var b stack.TwoBytes
+	s := b[:]
+	p := uintptr(unsafe.Pointer(&s))
+	v := (*[]byte)(unsafe.Pointer(p))
 
-// WriteUint32 writes an uint32 value into writer.
-func WriteUint32(writer io.Writer, value uint32) (int, error) {
-	var b [4]byte
-	binary.BigEndian.PutUint32(b[:], value)
-	return writer.Write(b[:])
+	binary.BigEndian.PutUint16(*v, value)
+	return writer.Write(*v)
 }
 
 // WriteUint64 writes an uint64 value into writer.
 func WriteUint64(writer io.Writer, value uint64) (int, error) {
-	var b [8]byte
-	binary.BigEndian.PutUint64(b[:], value)
-	return writer.Write(b[:])
+	var b stack.EightBytes
+	s := b[:]
+	p := uintptr(unsafe.Pointer(&s))
+	v := (*[]byte)(unsafe.Pointer(p))
+
+	binary.BigEndian.PutUint64(*v, value)
+	return writer.Write(*v)
 }