vorteil/vorteil

package vmdk

/**
 * SPDX-License-Identifier: Apache-2.0
 * Copyright 2020 vorteil.io Pty Ltd
 */

import (
    "encoding/binary"
    "fmt"
    "math/rand"
    "strings"
    "time"
)

const (
    Magic           = 0x564d444b
    SectorSize      = 0x200
    GrainSize       = 0x10000
    SectorsPerGrain = GrainSize / SectorSize
    TableMaxRows    = 512
    TableRowSize    = 4
    TableSectors    = TableMaxRows * TableRowSize / SectorSize
)

type Header struct {
    MagicNumber        uint32 // 0
    Version            uint32 // 4
    Flags              uint32 // 8
    Capacity           uint64 // 12
    GrainSize          uint64 // 20
    DescriptorOffset   uint64 // 28
    DescriptorSize     uint64 // 36
    NumGTEsPerGT       uint32 // 44
    RGDOffset          uint64 // 48
    GDOffset           uint64 // 56
    OverHead           uint64 // 64
    UncleanShutdown    byte   // 72
    SingleEndLineChar  byte   // 73
    NonEndLineChar     byte   // 74
    DoubleEndLineChar1 byte   // 75
    DoubleEndLineChar2 byte   // 76
    CompressAlgorithm  uint16 // 77
    Pad                [433]uint8
}

func generateDiskUID() string {
    rand.Seed(time.Now().UTC().UnixNano())
    b := [4]byte{}
    binary.LittleEndian.PutUint32(b[:], uint32(rand.Int31()))
    return strings.ToUpper(fmt.Sprintf("%X", b))
}