From db5c77a4733b8124473e3f311026533d3a9acbda Mon Sep 17 00:00:00 2001
From: shamaton <shamaton77@gmail.com>
Date: Wed, 4 Aug 2021 22:12:11 +0900
Subject: [PATCH 1/2] not using unsafe to decode string

---
 internal/decoding/decoding.go |  4 ++--
 internal/decoding/string.go   | 18 +++++++++++++-----
 internal/decoding/struct.go   | 36 +++++++++++++++++++++++++++--------
 3 files changed, 43 insertions(+), 15 deletions(-)

diff --git a/internal/decoding/decoding.go b/internal/decoding/decoding.go
index 78b95b6..9e4eebb 100644
--- a/internal/decoding/decoding.go
+++ b/internal/decoding/decoding.go
@@ -120,7 +120,7 @@ func (d *decoder) decode(rv reflect.Value, offset int) (int, error) {
 			if err != nil {
 				return 0, err
 			}
-			bs, offset := d.asStringByte(offset, l, k)
+			bs, offset := d.asStringByteByLength(offset, l, k)
 			rv.SetBytes(bs)
 			return offset, nil
 		}
@@ -201,7 +201,7 @@ func (d *decoder) decode(rv reflect.Value, offset int) (int, error) {
 			if l > rv.Len() {
 				return 0, fmt.Errorf("%v len is %d, but msgpack has %d elements", rv.Type(), rv.Len(), l)
 			}
-			bs, offset := d.asStringByte(offset, l, k)
+			bs, offset := d.asStringByteByLength(offset, l, k)
 			for i, b := range bs {
 				rv.Index(i).SetUint(uint64(b))
 			}
diff --git a/internal/decoding/string.go b/internal/decoding/string.go
index d2e0687..ae5a515 100644
--- a/internal/decoding/string.go
+++ b/internal/decoding/string.go
@@ -3,7 +3,6 @@ package decoding
 import (
 	"encoding/binary"
 	"reflect"
-	"unsafe"
 
 	"github.com/shamaton/msgpack/v2/def"
 )
@@ -42,15 +41,24 @@ func (d *decoder) stringByteLength(offset int, k reflect.Kind) (int, int, error)
 }
 
 func (d *decoder) asString(offset int, k reflect.Kind) (string, int, error) {
-	l, offset, err := d.stringByteLength(offset, k)
+	bs, offset, err := d.asStringByte(offset, k)
 	if err != nil {
 		return emptyString, 0, err
 	}
-	bs, offset := d.asStringByte(offset, l, k)
-	return *(*string)(unsafe.Pointer(&bs)), offset, nil
+	return string(bs), offset, nil
+}
+
+func (d *decoder) asStringByte(offset int, k reflect.Kind) ([]byte, int, error) {
+	l, offset, err := d.stringByteLength(offset, k)
+	if err != nil {
+		return emptyBytes, 0, err
+	}
+
+	b, o := d.asStringByteByLength(offset, l, k)
+	return b, o, nil
 }
 
-func (d *decoder) asStringByte(offset int, l int, k reflect.Kind) ([]byte, int) {
+func (d *decoder) asStringByteByLength(offset int, l int, k reflect.Kind) ([]byte, int) {
 	if l < 1 {
 		return emptyBytes, offset
 	}
diff --git a/internal/decoding/struct.go b/internal/decoding/struct.go
index 6caadc0..2169d39 100644
--- a/internal/decoding/struct.go
+++ b/internal/decoding/struct.go
@@ -9,7 +9,8 @@ import (
 )
 
 type structCacheTypeMap struct {
-	m map[string]int
+	keys    [][]byte
+	indexes []int
 }
 
 type structCacheTypeArray struct {
@@ -95,28 +96,47 @@ func (d *decoder) setStructFromMap(rv reflect.Value, offset int, k reflect.Kind)
 		return 0, err
 	}
 
-	// find or create reference
 	var sctm *structCacheTypeMap
 	cache, cacheFind := mapSCTM.Load(rv.Type())
 	if !cacheFind {
-		sctm = &structCacheTypeMap{m: map[string]int{}}
+		sctm = &structCacheTypeMap{}
 		for i := 0; i < rv.NumField(); i++ {
 			if ok, name := d.CheckField(rv.Type().Field(i)); ok {
-				sctm.m[name] = i
+				sctm.keys = append(sctm.keys, []byte(name))
+				sctm.indexes = append(sctm.indexes, i)
 			}
 		}
 		mapSCTM.Store(rv.Type(), sctm)
 	} else {
 		sctm = cache.(*structCacheTypeMap)
 	}
-	// set value if string correct
+
 	for i := 0; i < l; i++ {
-		key, o2, err := d.asString(o, k)
+		dataKey, o2, err := d.asStringByte(o, k)
 		if err != nil {
 			return 0, err
 		}
-		if _, ok := sctm.m[key]; ok {
-			o2, err = d.decode(rv.Field(sctm.m[key]), o2)
+
+		fieldIndex := -1
+		for keyIndex, keyBytes := range sctm.keys {
+			if len(keyBytes) != len(dataKey) {
+				continue
+			}
+
+			fieldIndex = sctm.indexes[keyIndex]
+			for dataIndex := range dataKey {
+				if dataKey[dataIndex] != keyBytes[dataIndex] {
+					fieldIndex = -1
+					break
+				}
+			}
+			if fieldIndex >= 0 {
+				break
+			}
+		}
+
+		if fieldIndex >= 0 {
+			o2, err = d.decode(rv.Field(fieldIndex), o2)
 			if err != nil {
 				return 0, err
 			}

From 48efb601c1cf58c16e61c643f94280ddab55431b Mon Sep 17 00:00:00 2001
From: shamaton <shamaton77@gmail.com>
Date: Wed, 4 Aug 2021 22:13:06 +0900
Subject: [PATCH 2/2] update README.md

---
 README.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/README.md b/README.md
index f217cd1..8a3a84f 100644
--- a/README.md
+++ b/README.md
@@ -29,7 +29,7 @@ go get -u github.com/shamaton/msgpack
 package main
 
 import (
-  "github.com/shamaton/msgpack"
+  "github.com/shamaton/msgpack/v2"
 )
 
 func main() {