56 lines
1.8 KiB
Go
56 lines
1.8 KiB
Go
// Copyright 2016 The go-ethereum Authors
|
|
// This file is part of the go-ethereum library.
|
|
//
|
|
// The go-ethereum library is free software: you can redistribute it and/or modify
|
|
// it under the terms of the GNU Lesser General Public License as published by
|
|
// the Free Software Foundation, either version 3 of the License, or
|
|
// (at your option) any later version.
|
|
//
|
|
// The go-ethereum library is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU Lesser General Public License for more details.
|
|
//
|
|
// You should have received a copy of the GNU Lesser General Public License
|
|
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
// Contains the Whisper protocol Topic element.
|
|
|
|
package whisperv6
|
|
|
|
import (
|
|
"github.com/ethereum/go-ethereum/common"
|
|
"github.com/ethereum/go-ethereum/common/hexutil"
|
|
)
|
|
|
|
// Topic represents a cryptographically secure, probabilistic partial
|
|
// classifications of a message, determined as the first (left) 4 bytes of the
|
|
// SHA3 hash of some arbitrary data given by the original author of the message.
|
|
type TopicType [TopicLength]byte
|
|
|
|
func BytesToTopic(b []byte) (t TopicType) {
|
|
sz := TopicLength
|
|
if x := len(b); x < TopicLength {
|
|
sz = x
|
|
}
|
|
for i := 0; i < sz; i++ {
|
|
t[i] = b[i]
|
|
}
|
|
return t
|
|
}
|
|
|
|
// String converts a topic byte array to a string representation.
|
|
func (topic *TopicType) String() string {
|
|
return string(common.ToHex(topic[:]))
|
|
}
|
|
|
|
// MarshalText returns the hex representation of t.
|
|
func (t TopicType) MarshalText() ([]byte, error) {
|
|
return hexutil.Bytes(t[:]).MarshalText()
|
|
}
|
|
|
|
// UnmarshalText parses a hex representation to a topic.
|
|
func (t *TopicType) UnmarshalText(input []byte) error {
|
|
return hexutil.UnmarshalFixedText("Topic", input, t[:])
|
|
}
|