-
Notifications
You must be signed in to change notification settings - Fork 2
/
prelude.go
47 lines (38 loc) · 1.07 KB
/
prelude.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
// SPDX-FileCopyrightText: 2024 Serpent OS Developers
// SPDX-License-Identifier: MPL-2.0
package stone1
import (
"errors"
"github.com/serpent-os/libstone-go"
"github.com/serpent-os/libstone-go/internal/readers"
)
var (
integrityCheck = [21]byte{0, 0, 1, 0, 0, 2, 0, 0, 3, 0, 0, 4, 0, 0, 5, 0, 0, 6, 0, 0, 7}
)
type StoneType uint8
const (
BinaryStone StoneType = iota + 1
DeltaStone
RepositoryStone
BuildManifestStone
)
type Prelude struct {
NumPayloads uint16
StoneType StoneType
}
func NewPrelude(genericPre libstone.Prelude) (Prelude, error) {
if genericPre.Version != libstone.V1 {
return Prelude{}, errors.New("prelude version is not 1")
}
if len(genericPre.Data) < len(libstone.PreludeData{}) {
return Prelude{}, errors.New("insufficient number of bytes to parse a V1 prelude")
}
wlk := readers.ByteWalker(genericPre.Data[:])
var pre Prelude
pre.NumPayloads = wlk.Uint16()
if [21]byte(wlk.Ahead(len(integrityCheck))) != integrityCheck {
return Prelude{}, errors.New("V1 integrity check failed")
}
pre.StoneType = StoneType(wlk.Uint8())
return pre, nil
}