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-rw-r--r--swarm/multihash/multihash.go92
1 files changed, 0 insertions, 92 deletions
diff --git a/swarm/multihash/multihash.go b/swarm/multihash/multihash.go
deleted file mode 100644
index 3306e3a6d..000000000
--- a/swarm/multihash/multihash.go
+++ /dev/null
@@ -1,92 +0,0 @@
-// Copyright 2018 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/>.
-
-package multihash
-
-import (
- "bytes"
- "encoding/binary"
- "errors"
- "fmt"
-)
-
-const (
- defaultMultihashLength = 32
- defaultMultihashTypeCode = 0x1b
-)
-
-var (
- multihashTypeCode uint8
- MultihashLength = defaultMultihashLength
-)
-
-func init() {
- multihashTypeCode = defaultMultihashTypeCode
- MultihashLength = defaultMultihashLength
-}
-
-// check if valid swarm multihash
-func isSwarmMultihashType(code uint8) bool {
- return code == multihashTypeCode
-}
-
-// GetMultihashLength returns the digest length of the provided multihash
-// It will fail if the multihash is not a valid swarm mulithash
-func GetMultihashLength(data []byte) (int, int, error) {
- cursor := 0
- typ, c := binary.Uvarint(data)
- if c <= 0 {
- return 0, 0, errors.New("unreadable hashtype field")
- }
- if !isSwarmMultihashType(uint8(typ)) {
- return 0, 0, fmt.Errorf("hash code %x is not a swarm hashtype", typ)
- }
- cursor += c
- hashlength, c := binary.Uvarint(data[cursor:])
- if c <= 0 {
- return 0, 0, errors.New("unreadable length field")
- }
- cursor += c
-
- // we cheekily assume hashlength < maxint
- inthashlength := int(hashlength)
- if len(data[c:]) < inthashlength {
- return 0, 0, errors.New("length mismatch")
- }
- return inthashlength, cursor, nil
-}
-
-// FromMulithash returns the digest portion of the multihash
-// It will fail if the multihash is not a valid swarm multihash
-func FromMultihash(data []byte) ([]byte, error) {
- hashLength, _, err := GetMultihashLength(data)
- if err != nil {
- return nil, err
- }
- return data[len(data)-hashLength:], nil
-}
-
-// ToMulithash wraps the provided digest data with a swarm mulithash header
-func ToMultihash(hashData []byte) []byte {
- buf := bytes.NewBuffer(nil)
- b := make([]byte, 8)
- c := binary.PutUvarint(b, uint64(multihashTypeCode))
- buf.Write(b[:c])
- c = binary.PutUvarint(b, uint64(len(hashData)))
- buf.Write(b[:c])
- buf.Write(hashData)
- return buf.Bytes()
-}