neo-go/pkg/network/payload/inventory.go
2018-01-30 11:56:36 +01:00

95 lines
2.2 KiB
Go

package payload
import (
"encoding/binary"
"io"
. "github.com/anthdm/neo-go/pkg/util"
)
// The node can broadcast the object information it owns by this message.
// The message can be sent automatically or can be used to answer getbloks messages.
// InventoryType is the type of an object in the Inventory message.
type InventoryType uint8
// String implements the Stringer interface.
func (i InventoryType) String() string {
switch i {
case 0x01:
return "block"
case 0x02:
return "TX"
case 0xe0:
return "consensus"
default:
return "unknown inventory type"
}
}
// Valid returns true if the inventory (type) is known.
func (i InventoryType) Valid() bool {
return i == BlockType || i == TXType || i == ConsensusType
}
// List of valid InventoryTypes.
const (
BlockType InventoryType = 0x01 // 1
TXType = 0x02 // 2
ConsensusType = 0xe0 // 224
)
// Inventory payload
type Inventory struct {
// Type if the object hash.
Type InventoryType
// The hash of the object (uint256).
Hashes []Uint256
}
// NewInventory return a pointer to an Inventory.
func NewInventory(typ InventoryType, hashes []Uint256) *Inventory {
return &Inventory{
Type: typ,
Hashes: hashes,
}
}
// DecodeBinary implements the Payload interface.
func (p *Inventory) DecodeBinary(r io.Reader) error {
// TODO: is there a list len?
// The first byte is the type the second byte seems to be
// always one on docker privnet.
var listLen uint8
err := binary.Read(r, binary.LittleEndian, &p.Type)
err = binary.Read(r, binary.LittleEndian, &listLen)
p.Hashes = make([]Uint256, listLen)
for i := 0; i < int(listLen); i++ {
if err := binary.Read(r, binary.LittleEndian, &p.Hashes[i]); err != nil {
return err
}
}
return err
}
// EncodeBinary implements the Payload interface.
func (p *Inventory) EncodeBinary(w io.Writer) error {
listLen := uint8(len(p.Hashes))
err := binary.Write(w, binary.LittleEndian, p.Type)
err = binary.Write(w, binary.LittleEndian, listLen)
for i := 0; i < len(p.Hashes); i++ {
if err := binary.Write(w, binary.LittleEndian, p.Hashes[i]); err != nil {
return err
}
}
return err
}
// Size implements the Payloader interface.
func (p *Inventory) Size() uint32 {
return 1 + 1 + 32 // ?
}