From 6de7a04cbd4729bbb0f1ae58f42c948c5e9c7dbc Mon Sep 17 00:00:00 2001
From: crusader <crusader@atgame.net>
Date: Tue, 23 Oct 2018 01:14:52 +0900
Subject: [PATCH] ing

---
 encoding/binary/binary.go | 68 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 68 insertions(+)
 create mode 100644 encoding/binary/binary.go

diff --git a/encoding/binary/binary.go b/encoding/binary/binary.go
new file mode 100644
index 0000000..8e339a8
--- /dev/null
+++ b/encoding/binary/binary.go
@@ -0,0 +1,68 @@
+package binary
+
+import (
+	"encoding/binary"
+	"fmt"
+	"strconv"
+	"strings"
+)
+
+// StrToBytes converts string("00 00 00 00 00 00 00 00") to []byte
+func StrToBytes(str string) []byte {
+	bytes := make([]byte, 8)
+	for i, e := range strings.Fields(str) {
+		b, _ := strconv.ParseUint(e, 16, 64)
+		bytes[i] = byte(b)
+	}
+	return bytes
+}
+
+// BytesToStr converts []byte to string("00 00 00 00 00 00 00 00")
+func BytesToStr(bytes ...byte) string {
+	strs := []string{}
+	for _, b := range bytes {
+		strs = append(strs, fmt.Sprintf("%02x", b))
+	}
+	return strings.Join(strs, " ")
+}
+
+// BytesToUInt converts []byte to uint64
+func BytesToUInt(bytes ...byte) uint64 {
+	padding := make([]byte, 8-len(bytes))
+	i := binary.BigEndian.Uint64(append(padding, bytes...))
+	return i
+}
+
+// UintToBytes converts uint64 to []byte
+func UintToBytes(i uint64, size int) []byte {
+	bytes := make([]byte, 8)
+	binary.BigEndian.PutUint64(bytes, i)
+	return bytes[8-size : 8]
+}
+
+// BytesToInt converts []byte to int64
+func BytesToInt(bytes ...byte) int64 {
+	if 0x7f < bytes[0] {
+		mask := uint64(1<<uint(len(bytes)*8-1) - 1)
+
+		bytes[0] &= 0x7f
+		i := BytesToUInt(bytes...)
+		i = (^i + 1) & mask
+		return int64(-i)
+
+	} else {
+		i := BytesToUInt(bytes...)
+		return int64(i)
+	}
+}
+
+// IntToBytes converts int to []byte
+func IntToBytes(i int, size int) []byte {
+	var ui uint64
+	if 0 < i {
+		ui = uint64(i)
+	} else {
+		ui = (^uint64(-i) + 1)
+	}
+	return UintToBytes(ui, size)
+}