golang hash 代码
文件路径：/src/hash/hash.go
/ Copyright 2009 The Go Authors. All rights reserved.
/ Use of this source code is governed by a BSD-style
/ license that can be found in the LICENSE file.
/ Package hash provides interfaces for hash functions.
package hash
import "io"
/ Hash is the common interface implemented by all hash functions.
/
/ Hash implementations in the standard library (e.g. hash/crc32 and
/ crypto/sha256) implement the encoding.BinaryMarshaler and
/ encoding.BinaryUnmarshaler interfaces. Marshaling a hash implementation
/ allows its internal state to be saved and used for additional processing
/ later, without having to re-write the data previously written to the hash.
/ The hash state may contain portions of the input in its original form,
/ which users are expected to handle for any possible security implications.
/
/ Compatibility: Any future changes to hash or crypto packages will endeavor
/ to maintain compatibility with state encoded using previous versions.
/ That is, any released versions of the packages should be able to
/ decode data written with any previously released version,
/ subject to issues such as security fixes.
/ See the Go compatibility document for background: https://golang.org/doc/go1compat
type Hash interface {
/ Write (via the embedded io.Writer interface) adds more data to the running hash.
/ It never returns an error.
io.Writer
/ Sum appends the current hash to b and returns the resulting slice.
/ It does not change the underlying hash state.
Sum(b []byte) []byte
/ Reset resets the Hash to its initial state.
Reset()
/ Size returns the number of bytes Sum will return.
Size() int
/ BlockSize returns the hash's underlying block size.
/ The Write method must be able to accept any amount
/ of data, but it may operate more efficiently if all writes
/ are a multiple of the block size.
BlockSize() int
}
/ Hash32 is the common interface implemented by all 32-bit hash functions.
type Hash32 interface {
Hash
Sum32() uint32
}
/ Hash64 is the common interface implemented by all 64-bit hash functions.
type Hash64 interface {
Hash
Sum64() uint64
}