Source file src/pkg/hash/hash.go

     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 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 one with zero bytes written.
    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	}