1 files changed, 133 insertions, 0 deletions
diff --git a/src/pkg/hash/fnv/fnv.go b/src/pkg/hash/fnv/fnv.go
new file mode 100644
index 000000000..66ab5a635
--- /dev/null
+++ b/src/pkg/hash/fnv/fnv.go
@@ -0,0 +1,133 @@
+// 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
+}