59 lines
1.3 KiB
Go
59 lines
1.3 KiB
Go
package hashenc
|
|
|
|
import (
|
|
"hash"
|
|
|
|
"codeberg.org/gruf/go-bytes"
|
|
)
|
|
|
|
// HashEncoder defines an interface for calculating encoded hash sums of binary data
|
|
type HashEncoder interface {
|
|
// EncodeSum calculates the hash sum of src and encodes (at most) Size() into dst
|
|
EncodeSum(dst []byte, src []byte)
|
|
|
|
// EncodedSum calculates the encoded hash sum of src and returns data in a newly allocated bytes.Bytes
|
|
EncodedSum(src []byte) bytes.Bytes
|
|
|
|
// Size returns the expected length of encoded hashes
|
|
Size() int
|
|
}
|
|
|
|
// New returns a new HashEncoder instance based on supplied hash.Hash and Encoder supplying functions
|
|
func New(hash hash.Hash, enc Encoder) HashEncoder {
|
|
hashSize := hash.Size()
|
|
return &henc{
|
|
hash: hash,
|
|
hbuf: make([]byte, hashSize),
|
|
enc: enc,
|
|
size: enc.EncodedLen(hashSize),
|
|
}
|
|
}
|
|
|
|
// henc is the HashEncoder implementation
|
|
type henc struct {
|
|
hash hash.Hash
|
|
hbuf []byte
|
|
enc Encoder
|
|
size int
|
|
}
|
|
|
|
func (henc *henc) EncodeSum(dst []byte, src []byte) {
|
|
// Hash supplied bytes
|
|
henc.hash.Reset()
|
|
henc.hash.Write(src)
|
|
henc.hbuf = henc.hash.Sum(henc.hbuf[:0])
|
|
|
|
// Encode the hashsum and return a copy
|
|
henc.enc.Encode(dst, henc.hbuf)
|
|
}
|
|
|
|
func (henc *henc) EncodedSum(src []byte) bytes.Bytes {
|
|
dst := make([]byte, henc.size)
|
|
henc.EncodeSum(dst, src)
|
|
return bytes.ToBytes(dst)
|
|
}
|
|
|
|
func (henc *henc) Size() int {
|
|
return henc.size
|
|
}
|