1 // Copyright 2009 The Go Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style 3 // license that can be found in the LICENSE file. 4 5 // Package hash provides interfaces for hash functions. 6 package hash 7 8 import "io" 9 10 // Hash is the common interface implemented by all hash functions. 11 type Hash interface { 12 // Write (via the embedded io.Writer interface) adds more data to the running hash. 13 // It never returns an error. 14 io.Writer 15 16 // Sum appends the current hash to b and returns the resulting slice. 17 // It does not change the underlying hash state. 18 Sum(b []byte) []byte 19 20 // Reset resets the Hash to its initial state. 21 Reset() 22 23 // Size returns the number of bytes Sum will return. 24 Size() int 25 26 // BlockSize returns the hash's underlying block size. 27 // The Write method must be able to accept any amount 28 // of data, but it may operate more efficiently if all writes 29 // are a multiple of the block size. 30 BlockSize() int 31 } 32 33 // Hash32 is the common interface implemented by all 32-bit hash functions. 34 type Hash32 interface { 35 Hash 36 Sum32() uint32 37 } 38 39 // Hash64 is the common interface implemented by all 64-bit hash functions. 40 type Hash64 interface { 41 Hash 42 Sum64() uint64 43 } 44
