-
Notifications
You must be signed in to change notification settings - Fork 0
/
variantvector.go
110 lines (98 loc) · 2.79 KB
/
variantvector.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
package variantvector
import (
"errors"
"fmt"
"github.com/NIR3X/varsizedint"
)
type Type []any
func varsizedIntPack(packed []uint8, value uint64) []uint8 {
bytes := [varsizedint.MaxSize]uint8{}
bytesSize := varsizedint.Encode(bytes[:], value)
packed = append(packed, bytes[:bytesSize]...)
return packed
}
func Pack(variantVec Type) ([]uint8, error) {
packed := []uint8{}
packed = varsizedIntPack(packed, uint64(len(variantVec)))
for _, variant := range variantVec {
switch variant := variant.(type) {
case uint64:
packed = varsizedIntPack(packed, uint64(0))
packed = varsizedIntPack(packed, variant)
case string:
packed = varsizedIntPack(packed, uint64(1))
packed = varsizedIntPack(packed, uint64(len(variant)))
packed = append(packed, []uint8(variant)...)
case []uint8:
packed = varsizedIntPack(packed, uint64(2))
packed = varsizedIntPack(packed, uint64(len(variant)))
packed = append(packed, variant...)
default:
return nil, fmt.Errorf("invalid variant type: %T", variant)
}
}
return packed, nil
}
func varsizedIntUnpack(data []uint8, offset uint64) (uint64, uint64, error) {
if uint64(len(data)) < offset+1 {
return 0, 0, errors.New("insufficient data")
}
bytesSize := varsizedint.ParseSize(data[offset:])
if bytesSize < 0 || uint64(len(data)) < offset+uint64(bytesSize) {
return 0, 0, errors.New("invalid data")
}
x := varsizedint.Decode(data[offset:])
offset += uint64(bytesSize)
return x, offset, nil
}
func Unpack(data []uint8) (Type, error) {
offset := uint64(0)
variantVecSize, offset, err := varsizedIntUnpack(data, offset)
if err != nil {
return nil, err
}
variantVec := Type{}
for i := uint64(0); i < variantVecSize; i++ {
var variantIndex uint64
variantIndex, offset, err = varsizedIntUnpack(data, offset)
if err != nil {
return nil, err
}
switch variantIndex {
case 0:
var value uint64
value, offset, err = varsizedIntUnpack(data, offset)
if err != nil {
return nil, err
}
variantVec = append(variantVec, value)
case 1:
var valueSize uint64
valueSize, offset, err = varsizedIntUnpack(data, offset)
if err != nil {
return nil, err
}
if uint64(len(data)) < offset+valueSize {
return nil, errors.New("insufficient data")
}
value := string(data[offset : offset+valueSize])
offset += valueSize
variantVec = append(variantVec, value)
case 2:
var valueSize uint64
valueSize, offset, err = varsizedIntUnpack(data, offset)
if err != nil {
return nil, err
}
if uint64(len(data)) < offset+valueSize {
return nil, errors.New("insufficient data")
}
value := data[offset : offset+valueSize]
offset += valueSize
variantVec = append(variantVec, value)
default:
return nil, fmt.Errorf("invalid variant index: %d", variantIndex)
}
}
return variantVec, nil
}