--- /dev/null
+// 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.
+
+// The fnv package implements FNV-1 and FNV-1a,
+// non-cryptographic hash functions created by
+// Glenn Fowler, Landon Curt Noll, and Phong Vo.
+// See http://isthe.com/chongo/tech/comp/fnv/.
+package fnv
+
+import (
+ "encoding/binary"
+ "hash"
+ "os"
+ "unsafe"
+)
+
+type (
+ sum32 uint32
+ sum32a uint32
+ sum64 uint64
+ sum64a uint64
+)
+
+const (
+ offset32 = 2166136261
+ offset64 = 14695981039346656037
+ prime32 = 16777619
+ prime64 = 1099511628211
+)
+
+// New32 returns a new 32-bit FNV-1 hash.Hash.
+func New32() hash.Hash32 {
+ var s sum32 = offset32
+ return &s
+}
+
+// New32a returns a new 32-bit FNV-1a hash.Hash.
+func New32a() hash.Hash32 {
+ var s sum32a = offset32
+ return &s
+}
+
+// New64 returns a new 64-bit FNV-1 hash.Hash.
+func New64() hash.Hash64 {
+ var s sum64 = offset64
+ return &s
+}
+
+// New64a returns a new 64-bit FNV-1a hash.Hash.
+func New64a() hash.Hash64 {
+ var s sum64a = offset64
+ 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 *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, os.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, os.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, os.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, os.Error) {
+ hash := *s
+ for _, c := range data {
+ hash ^= sum64a(c)
+ hash *= prime64
+ }
+ *s = hash
+ return len(data), nil
+}
+
+func (s *sum32) Size() int { return unsafe.Sizeof(*s) }
+func (s *sum32a) Size() int { return unsafe.Sizeof(*s) }
+func (s *sum64) Size() int { return unsafe.Sizeof(*s) }
+func (s *sum64a) Size() int { return unsafe.Sizeof(*s) }
+
+func (s *sum32) Sum() []byte {
+ a := make([]byte, unsafe.Sizeof(*s))
+ binary.BigEndian.PutUint32(a, uint32(*s))
+ return a
+}
+
+func (s *sum32a) Sum() []byte {
+ a := make([]byte, unsafe.Sizeof(*s))
+ binary.BigEndian.PutUint32(a, uint32(*s))
+ return a
+}
+
+func (s *sum64) Sum() []byte {
+ a := make([]byte, unsafe.Sizeof(*s))
+ binary.BigEndian.PutUint64(a, uint64(*s))
+ return a
+}
+
+func (s *sum64a) Sum() []byte {
+ a := make([]byte, unsafe.Sizeof(*s))
+ binary.BigEndian.PutUint64(a, uint64(*s))
+ return a
+}
--- /dev/null
+// 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
+
+import (
+ "bytes"
+ "encoding/binary"
+ "hash"
+ "testing"
+)
+
+const testDataSize = 40
+
+type golden struct {
+ sum []byte
+ text string
+}
+
+var golden32 = []golden{
+ {[]byte{0x81, 0x1c, 0x9d, 0xc5}, ""},
+ {[]byte{0x05, 0x0c, 0x5d, 0x7e}, "a"},
+ {[]byte{0x70, 0x77, 0x2d, 0x38}, "ab"},
+ {[]byte{0x43, 0x9c, 0x2f, 0x4b}, "abc"},
+}
+
+var golden32a = []golden{
+ {[]byte{0x81, 0x1c, 0x9d, 0xc5}, ""},
+ {[]byte{0xe4, 0x0c, 0x29, 0x2c}, "a"},
+ {[]byte{0x4d, 0x25, 0x05, 0xca}, "ab"},
+ {[]byte{0x1a, 0x47, 0xe9, 0x0b}, "abc"},
+}
+
+var golden64 = []golden{
+ {[]byte{0xcb, 0xf2, 0x9c, 0xe4, 0x84, 0x22, 0x23, 0x25}, ""},
+ {[]byte{0xaf, 0x63, 0xbd, 0x4c, 0x86, 0x01, 0xb7, 0xbe}, "a"},
+ {[]byte{0x08, 0x32, 0x67, 0x07, 0xb4, 0xeb, 0x37, 0xb8}, "ab"},
+ {[]byte{0xd8, 0xdc, 0xca, 0x18, 0x6b, 0xaf, 0xad, 0xcb}, "abc"},
+}
+
+var golden64a = []golden{
+ {[]byte{0xcb, 0xf2, 0x9c, 0xe4, 0x84, 0x22, 0x23, 0x25}, ""},
+ {[]byte{0xaf, 0x63, 0xdc, 0x4c, 0x86, 0x01, 0xec, 0x8c}, "a"},
+ {[]byte{0x08, 0x9c, 0x44, 0x07, 0xb5, 0x45, 0x98, 0x6a}, "ab"},
+ {[]byte{0xe7, 0x1f, 0xa2, 0x19, 0x05, 0x41, 0x57, 0x4b}, "abc"},
+}
+
+func TestGolden32(t *testing.T) {
+ testGolden(t, New32(), golden32)
+}
+
+func TestGolden32a(t *testing.T) {
+ testGolden(t, New32a(), golden32a)
+}
+
+func TestGolden64(t *testing.T) {
+ testGolden(t, New64(), golden64)
+}
+
+func TestGolden64a(t *testing.T) {
+ testGolden(t, New64a(), golden64a)
+}
+
+func testGolden(t *testing.T, hash hash.Hash, gold []golden) {
+ for _, g := range gold {
+ hash.Reset()
+ done, error := hash.Write([]byte(g.text))
+ if error != nil {
+ t.Fatalf("write error: %s", error)
+ }
+ if done != len(g.text) {
+ t.Fatalf("wrote only %d out of %d bytes", done, len(g.text))
+ }
+ if actual := hash.Sum(); !bytes.Equal(g.sum, actual) {
+ t.Errorf("hash(%q) = 0x%x want 0x%x", g.text, actual, g.sum)
+ }
+ }
+}
+
+func TestIntegrity32(t *testing.T) {
+ testIntegrity(t, New32())
+}
+
+func TestIntegrity32a(t *testing.T) {
+ testIntegrity(t, New32a())
+}
+
+func TestIntegrity64(t *testing.T) {
+ testIntegrity(t, New64())
+}
+
+func TestIntegrity64a(t *testing.T) {
+ testIntegrity(t, New64a())
+}
+
+func testIntegrity(t *testing.T, h hash.Hash) {
+ data := []byte{'1', '2', 3, 4, 5}
+ h.Write(data)
+ sum := h.Sum()
+
+ if size := h.Size(); size != len(sum) {
+ t.Fatalf("Size()=%d but len(Sum())=%d", size, len(sum))
+ }
+
+ if a := h.Sum(); !bytes.Equal(sum, a) {
+ t.Fatalf("first Sum()=0x%x, second Sum()=0x%x", sum, a)
+ }
+
+ h.Reset()
+ h.Write(data)
+ if a := h.Sum(); !bytes.Equal(sum, a) {
+ t.Fatalf("Sum()=0x%x, but after Reset() Sum()=0x%x", sum, a)
+ }
+
+ h.Reset()
+ h.Write(data[:2])
+ h.Write(data[2:])
+ if a := h.Sum(); !bytes.Equal(sum, a) {
+ t.Fatalf("Sum()=0x%x, but with partial writes, Sum()=0x%x", sum, a)
+ }
+
+ switch h.Size() {
+ case 4:
+ sum32 := h.(hash.Hash32).Sum32()
+ if sum32 != binary.BigEndian.Uint32(sum) {
+ t.Fatalf("Sum()=0x%x, but Sum32()=0x%x", sum, sum32)
+ }
+ case 8:
+ sum64 := h.(hash.Hash64).Sum64()
+ if sum64 != binary.BigEndian.Uint64(sum) {
+ t.Fatalf("Sum()=0x%x, but Sum64()=0x%x", sum, sum64)
+ }
+ }
+}
+
+func Benchmark32(b *testing.B) {
+ benchmark(b, New32())
+}
+
+func Benchmark32a(b *testing.B) {
+ benchmark(b, New32a())
+}
+
+func Benchmark64(b *testing.B) {
+ benchmark(b, New64())
+}
+
+func Benchmark64a(b *testing.B) {
+ benchmark(b, New64a())
+}
+
+func benchmark(b *testing.B, h hash.Hash) {
+ b.ResetTimer()
+ b.SetBytes(testDataSize)
+ data := make([]byte, testDataSize)
+ for i, _ := range data {
+ data[i] = byte(i + 'a')
+ }
+
+ b.StartTimer()
+ for todo := b.N; todo != 0; todo-- {
+ h.Reset()
+ h.Write(data)
+ h.Sum()
+ }
+}