1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
|
// Copyright 2011 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 fnv implements FNV-1 and FNV-1a, non-cryptographic hash functions
// created by Glenn Fowler, Landon Curt Noll, and Phong Vo.
// See
// https://en.wikipedia.org/wiki/Fowler-Noll-Vo_hash_function.
//
// All the hash.Hash implementations returned by this package also
// implement encoding.BinaryMarshaler and encoding.BinaryUnmarshaler to
// marshal and unmarshal the internal state of the hash.
package fnv
import (
"errors"
"hash"
"math/bits"
)
type (
sum32 uint32
sum32a uint32
sum64 uint64
sum64a uint64
sum128 [2]uint64
sum128a [2]uint64
)
const (
offset32 = 2166136261
offset64 = 14695981039346656037
offset128Lower = 0x62b821756295c58d
offset128Higher = 0x6c62272e07bb0142
prime32 = 16777619
prime64 = 1099511628211
prime128Lower = 0x13b
prime128Shift = 24
)
// New32 returns a new 32-bit FNV-1 [hash.Hash].
// Its Sum method will lay the value out in big-endian byte order.
func New32() hash.Hash32 {
var s sum32 = offset32
return &s
}
// New32a returns a new 32-bit FNV-1a [hash.Hash].
// Its Sum method will lay the value out in big-endian byte order.
func New32a() hash.Hash32 {
var s sum32a = offset32
return &s
}
// New64 returns a new 64-bit FNV-1 [hash.Hash].
// Its Sum method will lay the value out in big-endian byte order.
func New64() hash.Hash64 {
var s sum64 = offset64
return &s
}
// New64a returns a new 64-bit FNV-1a [hash.Hash].
// Its Sum method will lay the value out in big-endian byte order.
func New64a() hash.Hash64 {
var s sum64a = offset64
return &s
}
// New128 returns a new 128-bit FNV-1 [hash.Hash].
// Its Sum method will lay the value out in big-endian byte order.
func New128() hash.Hash {
var s sum128
s[0] = offset128Higher
s[1] = offset128Lower
return &s
}
// New128a returns a new 128-bit FNV-1a [hash.Hash].
// Its Sum method will lay the value out in big-endian byte order.
func New128a() hash.Hash {
var s sum128a
s[0] = offset128Higher
s[1] = offset128Lower
return &s
}
func (s *sum32) Reset() { *s = offset32 }
func (s *sum32a) Reset() { *s = offset32 }
func (s *sum64) Reset() { *s = offset64 }
func (s *sum64a) Reset() { *s = offset64 }
func (s *sum128) Reset() { s[0] = offset128Higher; s[1] = offset128Lower }
func (s *sum128a) Reset() { s[0] = offset128Higher; s[1] = offset128Lower }
func (s *sum32) Sum32() uint32 { return uint32(*s) }
func (s *sum32a) Sum32() uint32 { return uint32(*s) }
func (s *sum64) Sum64() uint64 { return uint64(*s) }
func (s *sum64a) Sum64() uint64 { return uint64(*s) }
func (s *sum32) Write(data []byte) (int, error) {
hash := *s
for _, c := range data {
hash *= prime32
hash ^= sum32(c)
}
*s = hash
return len(data), nil
}
func (s *sum32a) Write(data []byte) (int, error) {
hash := *s
for _, c := range data {
hash ^= sum32a(c)
hash *= prime32
}
*s = hash
return len(data), nil
}
func (s *sum64) Write(data []byte) (int, error) {
hash := *s
for _, c := range data {
hash *= prime64
hash ^= sum64(c)
}
*s = hash
return len(data), nil
}
func (s *sum64a) Write(data []byte) (int, error) {
hash := *s
for _, c := range data {
hash ^= sum64a(c)
hash *= prime64
}
*s = hash
return len(data), nil
}
func (s *sum128) Write(data []byte) (int, error) {
for _, c := range data {
// Compute the multiplication
s0, s1 := bits.Mul64(prime128Lower, s[1])
s0 += s[1]<<prime128Shift + prime128Lower*s[0]
// Update the values
s[1] = s1
s[0] = s0
s[1] ^= uint64(c)
}
return len(data), nil
}
func (s *sum128a) Write(data []byte) (int, error) {
for _, c := range data {
s[1] ^= uint64(c)
// Compute the multiplication
s0, s1 := bits.Mul64(prime128Lower, s[1])
s0 += s[1]<<prime128Shift + prime128Lower*s[0]
// Update the values
s[1] = s1
s[0] = s0
}
return len(data), nil
}
func (s *sum32) Size() int { return 4 }
func (s *sum32a) Size() int { return 4 }
func (s *sum64) Size() int { return 8 }
func (s *sum64a) Size() int { return 8 }
func (s *sum128) Size() int { return 16 }
func (s *sum128a) Size() int { return 16 }
func (s *sum32) BlockSize() int { return 1 }
func (s *sum32a) BlockSize() int { return 1 }
func (s *sum64) BlockSize() int { return 1 }
func (s *sum64a) BlockSize() int { return 1 }
func (s *sum128) BlockSize() int { return 1 }
func (s *sum128a) BlockSize() int { return 1 }
func (s *sum32) Sum(in []byte) []byte {
v := uint32(*s)
return append(in, byte(v>>24), byte(v>>16), byte(v>>8), byte(v))
}
func (s *sum32a) Sum(in []byte) []byte {
v := uint32(*s)
return append(in, byte(v>>24), byte(v>>16), byte(v>>8), byte(v))
}
func (s *sum64) Sum(in []byte) []byte {
v := uint64(*s)
return append(in, byte(v>>56), byte(v>>48), byte(v>>40), byte(v>>32), byte(v>>24), byte(v>>16), byte(v>>8), byte(v))
}
func (s *sum64a) Sum(in []byte) []byte {
v := uint64(*s)
return append(in, byte(v>>56), byte(v>>48), byte(v>>40), byte(v>>32), byte(v>>24), byte(v>>16), byte(v>>8), byte(v))
}
func (s *sum128) Sum(in []byte) []byte {
return append(in,
byte(s[0]>>56), byte(s[0]>>48), byte(s[0]>>40), byte(s[0]>>32), byte(s[0]>>24), byte(s[0]>>16), byte(s[0]>>8), byte(s[0]),
byte(s[1]>>56), byte(s[1]>>48), byte(s[1]>>40), byte(s[1]>>32), byte(s[1]>>24), byte(s[1]>>16), byte(s[1]>>8), byte(s[1]),
)
}
func (s *sum128a) Sum(in []byte) []byte {
return append(in,
byte(s[0]>>56), byte(s[0]>>48), byte(s[0]>>40), byte(s[0]>>32), byte(s[0]>>24), byte(s[0]>>16), byte(s[0]>>8), byte(s[0]),
byte(s[1]>>56), byte(s[1]>>48), byte(s[1]>>40), byte(s[1]>>32), byte(s[1]>>24), byte(s[1]>>16), byte(s[1]>>8), byte(s[1]),
)
}
const (
magic32 = "fnv\x01"
magic32a = "fnv\x02"
magic64 = "fnv\x03"
magic64a = "fnv\x04"
magic128 = "fnv\x05"
magic128a = "fnv\x06"
marshaledSize32 = len(magic32) + 4
marshaledSize64 = len(magic64) + 8
marshaledSize128 = len(magic128) + 8*2
)
func (s *sum32) MarshalBinary() ([]byte, error) {
b := make([]byte, 0, marshaledSize32)
b = append(b, magic32...)
b = appendUint32(b, uint32(*s))
return b, nil
}
func (s *sum32a) MarshalBinary() ([]byte, error) {
b := make([]byte, 0, marshaledSize32)
b = append(b, magic32a...)
b = appendUint32(b, uint32(*s))
return b, nil
}
func (s *sum64) MarshalBinary() ([]byte, error) {
b := make([]byte, 0, marshaledSize64)
b = append(b, magic64...)
b = appendUint64(b, uint64(*s))
return b, nil
}
func (s *sum64a) MarshalBinary() ([]byte, error) {
b := make([]byte, 0, marshaledSize64)
b = append(b, magic64a...)
b = appendUint64(b, uint64(*s))
return b, nil
}
func (s *sum128) MarshalBinary() ([]byte, error) {
b := make([]byte, 0, marshaledSize128)
b = append(b, magic128...)
b = appendUint64(b, s[0])
b = appendUint64(b, s[1])
return b, nil
}
func (s *sum128a) MarshalBinary() ([]byte, error) {
b := make([]byte, 0, marshaledSize128)
b = append(b, magic128a...)
b = appendUint64(b, s[0])
b = appendUint64(b, s[1])
return b, nil
}
func (s *sum32) UnmarshalBinary(b []byte) error {
if len(b) < len(magic32) || string(b[:len(magic32)]) != magic32 {
return errors.New("hash/fnv: invalid hash state identifier")
}
if len(b) != marshaledSize32 {
return errors.New("hash/fnv: invalid hash state size")
}
*s = sum32(readUint32(b[4:]))
return nil
}
func (s *sum32a) UnmarshalBinary(b []byte) error {
if len(b) < len(magic32a) || string(b[:len(magic32a)]) != magic32a {
return errors.New("hash/fnv: invalid hash state identifier")
}
if len(b) != marshaledSize32 {
return errors.New("hash/fnv: invalid hash state size")
}
*s = sum32a(readUint32(b[4:]))
return nil
}
func (s *sum64) UnmarshalBinary(b []byte) error {
if len(b) < len(magic64) || string(b[:len(magic64)]) != magic64 {
return errors.New("hash/fnv: invalid hash state identifier")
}
if len(b) != marshaledSize64 {
return errors.New("hash/fnv: invalid hash state size")
}
*s = sum64(readUint64(b[4:]))
return nil
}
func (s *sum64a) UnmarshalBinary(b []byte) error {
if len(b) < len(magic64a) || string(b[:len(magic64a)]) != magic64a {
return errors.New("hash/fnv: invalid hash state identifier")
}
if len(b) != marshaledSize64 {
return errors.New("hash/fnv: invalid hash state size")
}
*s = sum64a(readUint64(b[4:]))
return nil
}
func (s *sum128) UnmarshalBinary(b []byte) error {
if len(b) < len(magic128) || string(b[:len(magic128)]) != magic128 {
return errors.New("hash/fnv: invalid hash state identifier")
}
if len(b) != marshaledSize128 {
return errors.New("hash/fnv: invalid hash state size")
}
s[0] = readUint64(b[4:])
s[1] = readUint64(b[12:])
return nil
}
func (s *sum128a) UnmarshalBinary(b []byte) error {
if len(b) < len(magic128a) || string(b[:len(magic128a)]) != magic128a {
return errors.New("hash/fnv: invalid hash state identifier")
}
if len(b) != marshaledSize128 {
return errors.New("hash/fnv: invalid hash state size")
}
s[0] = readUint64(b[4:])
s[1] = readUint64(b[12:])
return nil
}
// readUint32 is semantically the same as [binary.BigEndian.Uint32]
// We copied this function because we can not import "encoding/binary" here.
func readUint32(b []byte) uint32 {
_ = b[3]
return uint32(b[3]) | uint32(b[2])<<8 | uint32(b[1])<<16 | uint32(b[0])<<24
}
// appendUint32 is semantically the same as [binary.BigEndian.AppendUint32]
// We copied this function because we can not import "encoding/binary" here.
func appendUint32(b []byte, x uint32) []byte {
return append(b,
byte(x>>24),
byte(x>>16),
byte(x>>8),
byte(x),
)
}
// appendUint64 is semantically the same as [binary.BigEndian.AppendUint64]
// We copied this function because we can not import "encoding/binary" here.
func appendUint64(b []byte, x uint64) []byte {
return append(b,
byte(x>>56),
byte(x>>48),
byte(x>>40),
byte(x>>32),
byte(x>>24),
byte(x>>16),
byte(x>>8),
byte(x),
)
}
// readUint64 is semantically the same as [binary.BigEndian.Uint64]
// We copied this function because we can not import "encoding/binary" here.
func readUint64(b []byte) uint64 {
_ = b[7]
return uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56
}
|
