diff --git a/nbt/README.md b/nbt/README.md index b28c217..8f9379b 100644 --- a/nbt/README.md +++ b/nbt/README.md @@ -1,4 +1,5 @@ # NBT +This is copied from [mc-go](https://github.com/Tnze/go-mc) until PRs to add support for needed features is merged in. This package implement the Named Binary Tag format of Minecraft. # Docs [![GoDoc](https://godoc.org/github.com/Tnze/go-mc/nbt?status.svg)](https://godoc.org/github.com/Tnze/go-mc/nbt) \ No newline at end of file diff --git a/nbt/bigtest.nbt b/nbt/bigtest.nbt new file mode 100644 index 0000000..a2021df Binary files /dev/null and b/nbt/bigtest.nbt differ diff --git a/nbt/marshal.go b/nbt/marshal.go index 498e5e1..0f2532d 100644 --- a/nbt/marshal.go +++ b/nbt/marshal.go @@ -5,12 +5,26 @@ import ( "io" "math" "reflect" + "strings" +) + +var ( + ErrMustBeStruct = errors.New("a compound can only be a struct") ) func Marshal(w io.Writer, v interface{}) error { return NewEncoder(w).Encode(v) } +func MarshalCompound(w io.Writer, v interface{}, rootTagName string) error { + enc := NewEncoder(w) + val := reflect.ValueOf(v) + if val.Kind() != reflect.Struct { + return ErrMustBeStruct + } + return enc.marshal(val, TagCompound, rootTagName) +} + type Encoder struct { w io.Writer } @@ -21,166 +35,86 @@ func NewEncoder(w io.Writer) *Encoder { func (e *Encoder) Encode(v interface{}) error { val := reflect.ValueOf(v) - return e.marshal(val, "") + return e.marshal(val, getTagType(val.Type()), "") } -func (e *Encoder) marshal(val reflect.Value, tagName string) error { - switch vk := val.Kind(); vk { - default: - return errors.New("unknown type " + vk.String()) +func (e *Encoder) marshal(val reflect.Value, tagType byte, tagName string) (err error) { + err = e.writeHeader(val, tagType, tagName) + err = e.writeValue(val, tagType) + return err +} - case reflect.Uint8: - if err := e.writeTag(TagByte, tagName); err != nil { - return err - } +func (e *Encoder) writeHeader(val reflect.Value, tagType byte, tagName string) (err error) { + if tagType == TagList { + eleType := getTagType(val.Type().Elem()) + err = e.writeListHeader(eleType, tagName, val.Len()) + } else { + err = e.writeTag(tagType, tagName) + } + return err +} + +func (e *Encoder) writeValue(val reflect.Value, tagType byte) error { + switch tagType { + default: + return errors.New("unsupported type " + val.Type().Kind().String()) + case TagByte: _, err := e.w.Write([]byte{byte(val.Uint())}) return err - - case reflect.Int16, reflect.Uint16: - if err := e.writeTag(TagShort, tagName); err != nil { - return err - } + case TagShort: return e.writeInt16(int16(val.Int())) - - case reflect.Int32, reflect.Uint32: - if err := e.writeTag(TagInt, tagName); err != nil { - return err - } + case TagInt: return e.writeInt32(int32(val.Int())) - - case reflect.Float32: - if err := e.writeTag(TagFloat, tagName); err != nil { - return err - } + case TagFloat: return e.writeInt32(int32(math.Float32bits(float32(val.Float())))) - - case reflect.Int64, reflect.Uint64: - if err := e.writeTag(TagLong, tagName); err != nil { - return err - } - return e.writeInt64(int64(val.Int())) - - case reflect.Float64: - if err := e.writeTag(TagDouble, tagName); err != nil { - return err - } + case TagLong: + return e.writeInt64(val.Int()) + case TagDouble: return e.writeInt64(int64(math.Float64bits(val.Float()))) - - case reflect.Array, reflect.Slice: + case TagByteArray, TagIntArray, TagLongArray: n := val.Len() - switch val.Type().Elem().Kind() { - case reflect.Uint8: // []byte - if err := e.writeTag(TagByteArray, tagName); err != nil { - return err - } - if err := e.writeInt32(int32(val.Len())); err != nil { - return err - } + if err := e.writeInt32(int32(n)); err != nil { + return err + } + + if tagType == TagByteArray { _, err := e.w.Write(val.Bytes()) return err + } else { + for i := 0; i < n; i++ { + v := val.Index(i).Int() - case reflect.Int32: - if err := e.writeTag(TagIntArray, tagName); err != nil { - return err - } - if err := e.writeInt32(int32(n)); err != nil { - return err - } - for i := 0; i < n; i++ { - if err := e.writeInt32(int32(val.Index(i).Int())); err != nil { - return err + var err error + if tagType == TagIntArray { + err = e.writeInt32(int32(v)) + } else if tagType == TagLongArray { + err = e.writeInt64(v) } - } - - case reflect.Int64: - if err := e.writeTag(TagLongArray, tagName); err != nil { - return err - } - if err := e.writeInt32(int32(n)); err != nil { - return err - } - for i := 0; i < n; i++ { - if err := e.writeInt64(val.Index(i).Int()); err != nil { - return err - } - } - - case reflect.Int16: - if err := e.writeListHeader(TagShort, tagName, val.Len()); err != nil { - return err - } - for i := 0; i < n; i++ { - if err := e.writeInt16(int16(val.Index(i).Int())); err != nil { - return err - } - } - - case reflect.Float32: - if err := e.writeListHeader(TagFloat, tagName, val.Len()); err != nil { - return err - } - for i := 0; i < n; i++ { - if err := e.writeInt32(int32(math.Float32bits(float32(val.Index(i).Float())))); err != nil { - return err - } - } - - case reflect.Float64: - if err := e.writeListHeader(TagDouble, tagName, val.Len()); err != nil { - return err - } - for i := 0; i < n; i++ { - if err := e.writeInt64(int64(math.Float64bits(val.Index(i).Float()))); err != nil { - return err - } - } - - case reflect.String: - if err := e.writeListHeader(TagString, tagName, n); err != nil { - return err - } - for i := 0; i < n; i++ { - // Write length of this string - s := val.Index(i).String() - if err := e.writeInt16(int16(len(s))); err != nil { - return err - } - // Write string - if _, err := e.w.Write([]byte(s)); err != nil { - return err - } - } - case reflect.Struct, reflect.Interface: - if err := e.writeListHeader(TagCompound, tagName, n); err != nil { - return err - } - for i := 0; i < n; i++ { - elemVal := val.Index(i) - if val.Type().Elem().Kind() == reflect.Interface { - elemVal = reflect.ValueOf(elemVal.Interface()) - } - err := e.marshal(elemVal, "") if err != nil { return err } } - default: - return errors.New("unknown type " + val.Type().String() + " slice") } - case reflect.String: - if err := e.writeTag(TagString, tagName); err != nil { - return err + case TagList: + for i := 0; i < val.Len(); i++ { + arrVal := val.Index(i) + err := e.writeValue(arrVal, getTagType(arrVal.Type())) + if err != nil { + return err + } } + + case TagString: if err := e.writeInt16(int16(val.Len())); err != nil { return err } _, err := e.w.Write([]byte(val.String())) return err - case reflect.Struct: - if err := e.writeTag(TagCompound, ""); err != nil { - return err + case TagCompound: + if val.Kind() == reflect.Interface { + val = reflect.ValueOf(val.Interface()) } n := val.NumField() @@ -191,12 +125,8 @@ func (e *Encoder) marshal(val reflect.Value, tagName string) error { continue // Private field } - tagName := f.Name - if tag != "" { - tagName = tag - } - - err := e.marshal(val.Field(i), tagName) + tagProps := parseTag(f, tag) + err := e.marshal(val.Field(i), tagProps.Type, tagProps.Name) if err != nil { return err } @@ -207,6 +137,65 @@ func (e *Encoder) marshal(val reflect.Value, tagName string) error { return nil } +func getTagType(vk reflect.Type) byte { + switch vk.Kind() { + case reflect.Uint8: + return TagByte + case reflect.Int16, reflect.Uint16: + return TagShort + case reflect.Int32, reflect.Uint32: + return TagInt + case reflect.Float32: + return TagFloat + case reflect.Int64, reflect.Uint64: + return TagLong + case reflect.Float64: + return TagDouble + case reflect.String: + return TagString + case reflect.Struct, reflect.Interface: + return TagCompound + case reflect.Array, reflect.Slice: + switch vk.Elem().Kind() { + case reflect.Uint8: // Special types for these values + return TagByteArray + case reflect.Int32: + return TagIntArray + case reflect.Int64: + return TagLongArray + default: + return TagList + } + default: + return TagNone + } +} + +type tagProps struct { + Name string + Type byte +} + +func parseTag(f reflect.StructField, tagName string) tagProps { + result := tagProps{} + result.Name = tagName + if result.Name == "" { + result.Name = f.Name + } + + nbtType := f.Tag.Get("nbt_type") + result.Type = getTagType(f.Type) + if strings.Contains(nbtType, "noarray") { + if IsArrayTag(result.Type) { + result.Type = TagList // for expanding the array to a standard list + } else { + panic("noarray is only supported for array types (byte, int, long)") + } + } + + return result +} + func (e *Encoder) writeTag(tagType byte, tagName string) error { if _, err := e.w.Write([]byte{tagType}); err != nil { return err @@ -233,11 +222,6 @@ func (e *Encoder) writeListHeader(elementType byte, tagName string, n int) (err return nil } -func (e *Encoder) writeNamelessTag(tagType byte, tagName string) error { - _, err := e.w.Write([]byte{tagType}) - return err -} - func (e *Encoder) writeInt16(n int16) error { _, err := e.w.Write([]byte{byte(n >> 8), byte(n)}) return err diff --git a/nbt/marshal_test.go b/nbt/marshal_test.go index b253563..75b4fbb 100644 --- a/nbt/marshal_test.go +++ b/nbt/marshal_test.go @@ -2,6 +2,7 @@ package nbt import ( "bytes" + "io/ioutil" "math" "testing" ) @@ -56,6 +57,19 @@ func TestMarshal_FloatArray(t *testing.T) { } } +func TestMarshal_String(t *testing.T) { + v := "Test" + out := []byte{TagString, 0x00, 0x00, 0, 4, + 'T', 'e', 's', 't'} + + var buf bytes.Buffer + if err := Marshal(&buf, v); err != nil { + t.Error(err) + } else if !bytes.Equal(buf.Bytes(), out) { + t.Errorf("output binary not right: got % 02x, want % 02x ", buf.Bytes(), out) + } +} + func TestMarshal_InterfaceArray(t *testing.T) { type Struct1 struct { Val int32 @@ -76,16 +90,15 @@ func TestMarshal_InterfaceArray(t *testing.T) { want: []byte{ TagList, 0x00, 0x00 /*no name*/, TagCompound, 0, 0, 0, 2, // 1st element - TagCompound, 0x00, 0x00, /*no name*/ TagInt, 0x00, 0x03, 'V', 'a', 'l', 0x00, 0x00, 0x00, 0x03, // 3 TagEnd, // 2nd element - TagCompound, 0x00, 0x00, /*no name*/ TagFloat, 0x00, 0x03, 'V', 'a', 'l', 0x3e, 0x99, 0x99, 0x9a, // 0.3 TagEnd, }, }, } + for _, tt := range tests { t.Run(tt.name, func(t *testing.T) { w := &bytes.Buffer{} @@ -105,24 +118,39 @@ func TestMarshal_StructArray(t *testing.T) { Val int32 } + type Struct2 struct { + T int32 + Ele Struct1 + } + + type StructCont struct { + V []Struct2 + } + tests := []struct { name string - args []Struct1 + args StructCont want []byte }{ { name: "One element struct array", - args: []Struct1{{3}, {-10}}, + args: StructCont{[]Struct2{{3, Struct1{3}}, {-10, Struct1{-10}}}}, want: []byte{ - TagList, 0x00, 0x00 /*no name*/, TagCompound, 0, 0, 0, 2, - // 1st element - TagCompound, 0x00, 0x00, /*no name*/ + TagCompound, 0x00, 0x00, + TagList, 0x00, 0x01, 'V', TagCompound, 0, 0, 0, 2, + // Struct2 + TagInt, 0x00, 0x01, 'T', 0x00, 0x00, 0x00, 0x03, + TagCompound, 0x00, 0x03, 'E', 'l', 'e', TagInt, 0x00, 0x03, 'V', 'a', 'l', 0x00, 0x00, 0x00, 0x03, // 3 TagEnd, + TagEnd, // 2nd element - TagCompound, 0x00, 0x00, /*no name*/ + TagInt, 0x00, 0x01, 'T', 0xff, 0xff, 0xff, 0xf6, + TagCompound, 0x00, 0x03, 'E', 'l', 'e', TagInt, 0x00, 0x03, 'V', 'a', 'l', 0xff, 0xff, 0xff, 0xf6, // -10 TagEnd, + TagEnd, + TagEnd, }, }, } @@ -139,3 +167,79 @@ func TestMarshal_StructArray(t *testing.T) { }) } } + + +// This test is for compliance with the "bigtest.dat" described in detail here: +// https://wiki.vg/NBT#bigtest.nbt +func TestMarshal_BigTest(t *testing.T) { + byteValues := make([]byte, 1000) + for n := 0; n < 1000; n++ { + byteValues[n] = byte((n*n*255 + n*7) % 100) + } + + type NestedCompound struct { + Name string `nbt:"name"` + Value float32 `nbt:"value"` + } + + type NestedCompoundCont struct { + Ham NestedCompound `nbt:"ham"` + Egg NestedCompound `nbt:"egg"` + } + + type ListCompound struct { + Name string `nbt:"name"` + CreatedOn int64 `nbt:"created-on"` + } + + val := struct { + LongTest int64 `nbt:"longTest"` + ShortTest int16 `nbt:"shortTest"` + StringTest string `nbt:"stringTest"` + FloatTest float32 `nbt:"floatTest"` + IntTest int32 `nbt:"intTest"` + NestedCompoundTest NestedCompoundCont `nbt:"nested compound test"` + ListTestLong []int64 `nbt:"listTest (long)" nbt_type:"noarray"` + ListTestCompound []ListCompound `nbt:"listTest (compound)"` + ByteTest byte `nbt:"byteTest"` + ByteArrayTest []byte `nbt:"byteArrayTest (the first 1000 values of (n*n*255+n*7)%100, starting with n=0 (0, 62, 34, 16, 8, ...))"` + DoubleTest float64 `nbt:"doubleTest"` + }{ + LongTest: 9223372036854775807, + ShortTest: 32767, + StringTest: "HELLO WORLD THIS IS A TEST STRING \xc3\x85\xc3\x84\xc3\x96!", + FloatTest: 0.49823147058486938, + IntTest: 2147483647, + NestedCompoundTest: NestedCompoundCont{ + NestedCompound{"Hampus", 0.75}, + NestedCompound{"Eggbert", 0.5}, + }, + ListTestLong: []int64{11, 12, 13, 14, 15}, + ListTestCompound: []ListCompound{ + {"Compound tag #0", 1264099775885}, + {"Compound tag #1", 1264099775885}, + }, + ByteTest: 127, + ByteArrayTest: byteValues, + DoubleTest: 0.49312871321823148, + } + + var b bytes.Buffer + err := MarshalCompound(&b, val, "Level") + if err != nil { + t.Error(err) + } + + want, err := ioutil.ReadFile("bigtest.nbt") + if err != nil { + t.Error(err) + } + + err = ioutil.WriteFile("bigtest_got.nbt", b.Bytes(), 0644) + if err != nil { + t.Error(err) + } + if !bytes.Equal(b.Bytes(), want) { + t.Errorf("got:\n[% 2x]\nwant:\n[% 2x]", b.Bytes(), want) + } +} diff --git a/nbt/nbt.go b/nbt/nbt.go index 794708e..53cf9f7 100644 --- a/nbt/nbt.go +++ b/nbt/nbt.go @@ -22,8 +22,13 @@ const ( TagCompound TagIntArray TagLongArray + TagNone = 0xFF ) +func IsArrayTag(ty byte) bool { + return ty == TagByteArray || ty == TagIntArray || ty == TagLongArray +} + type DecoderReader = interface { io.ByteScanner io.Reader