4.0初步改造

util/big_endian.go

@@ -0,0 +1,17 @@
+package util
+
+import "constraints"
+
+func PutBE[T constraints.Integer](b []byte, num T) []byte {
+	for i, n := 0, len(b); i < n; i++ {
+		b[i] = byte(num >> ((n - i - 1) << 3))
+	}
+	return b
+}
+
+func ReadBE[T constraints.Integer](b []byte) (num T) {
+	for i, n := 0, len(b); i < n; i++ {
+		num += T(b[i]) << ((n - i - 1) << 3)
+	}
+	return
+}