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-rw-r--r--libgo/go/hash/adler32/adler32.go88
-rw-r--r--libgo/go/hash/adler32/adler32_test.go63
-rw-r--r--libgo/go/hash/crc32/crc32.go111
-rw-r--r--libgo/go/hash/crc32/crc32_test.go76
-rw-r--r--libgo/go/hash/crc64/crc64.go96
-rw-r--r--libgo/go/hash/crc64/crc64_test.go78
-rw-r--r--libgo/go/hash/hash.go36
7 files changed, 548 insertions, 0 deletions
diff --git a/libgo/go/hash/adler32/adler32.go b/libgo/go/hash/adler32/adler32.go
new file mode 100644
index 000000000..cd0c2599a
--- /dev/null
+++ b/libgo/go/hash/adler32/adler32.go
@@ -0,0 +1,88 @@
+// 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.
+
+// This package implements the Adler-32 checksum.
+// Defined in RFC 1950:
+// Adler-32 is composed of two sums accumulated per byte: s1 is
+// the sum of all bytes, s2 is the sum of all s1 values. Both sums
+// are done modulo 65521. s1 is initialized to 1, s2 to zero. The
+// Adler-32 checksum is stored as s2*65536 + s1 in most-
+// significant-byte first (network) order.
+package adler32
+
+import (
+ "hash"
+ "os"
+)
+
+const (
+ mod = 65521
+)
+
+// The size of an Adler-32 checksum in bytes.
+const Size = 4
+
+// digest represents the partial evaluation of a checksum.
+type digest struct {
+ // invariant: (a < mod && b < mod) || a <= b
+ // invariant: a + b + 255 <= 0xffffffff
+ a, b uint32
+}
+
+func (d *digest) Reset() { d.a, d.b = 1, 0 }
+
+// New returns a new hash.Hash32 computing the Adler-32 checksum.
+func New() hash.Hash32 {
+ d := new(digest)
+ d.Reset()
+ return d
+}
+
+func (d *digest) Size() int { return Size }
+
+// Add p to the running checksum a, b.
+func update(a, b uint32, p []byte) (aa, bb uint32) {
+ for i := 0; i < len(p); i++ {
+ a += uint32(p[i])
+ b += a
+ // invariant: a <= b
+ if b > (0xffffffff-255)/2 {
+ a %= mod
+ b %= mod
+ // invariant: a < mod && b < mod
+ } else {
+ // invariant: a + b + 255 <= 2 * b + 255 <= 0xffffffff
+ }
+ }
+ return a, b
+}
+
+// Return the 32-bit checksum corresponding to a, b.
+func finish(a, b uint32) uint32 {
+ if b >= mod {
+ a %= mod
+ b %= mod
+ }
+ return b<<16 | a
+}
+
+func (d *digest) Write(p []byte) (nn int, err os.Error) {
+ d.a, d.b = update(d.a, d.b, p)
+ return len(p), nil
+}
+
+func (d *digest) Sum32() uint32 { return finish(d.a, d.b) }
+
+func (d *digest) Sum() []byte {
+ p := make([]byte, 4)
+ s := d.Sum32()
+ p[0] = byte(s >> 24)
+ p[1] = byte(s >> 16)
+ p[2] = byte(s >> 8)
+ p[3] = byte(s)
+ return p
+}
+
+// Checksum returns the Adler-32 checksum of data.
+func Checksum(data []byte) uint32 { return finish(update(1, 0, data)) }
diff --git a/libgo/go/hash/adler32/adler32_test.go b/libgo/go/hash/adler32/adler32_test.go
new file mode 100644
index 000000000..ffa5569bc
--- /dev/null
+++ b/libgo/go/hash/adler32/adler32_test.go
@@ -0,0 +1,63 @@
+// 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 adler32
+
+import (
+ "io"
+ "testing"
+)
+
+type _Adler32Test struct {
+ out uint32
+ in string
+}
+
+var golden = []_Adler32Test{
+ {0x1, ""},
+ {0x620062, "a"},
+ {0x12600c4, "ab"},
+ {0x24d0127, "abc"},
+ {0x3d8018b, "abcd"},
+ {0x5c801f0, "abcde"},
+ {0x81e0256, "abcdef"},
+ {0xadb02bd, "abcdefg"},
+ {0xe000325, "abcdefgh"},
+ {0x118e038e, "abcdefghi"},
+ {0x158603f8, "abcdefghij"},
+ {0x3f090f02, "Discard medicine more than two years old."},
+ {0x46d81477, "He who has a shady past knows that nice guys finish last."},
+ {0x40ee0ee1, "I wouldn't marry him with a ten foot pole."},
+ {0x16661315, "Free! Free!/A trip/to Mars/for 900/empty jars/Burma Shave"},
+ {0x5b2e1480, "The days of the digital watch are numbered. -Tom Stoppard"},
+ {0x8c3c09ea, "Nepal premier won't resign."},
+ {0x45ac18fd, "For every action there is an equal and opposite government program."},
+ {0x53c61462, "His money is twice tainted: 'taint yours and 'taint mine."},
+ {0x7e511e63, "There is no reason for any individual to have a computer in their home. -Ken Olsen, 1977"},
+ {0xe4801a6a, "It's a tiny change to the code and not completely disgusting. - Bob Manchek"},
+ {0x61b507df, "size: a.out: bad magic"},
+ {0xb8631171, "The major problem is with sendmail. -Mark Horton"},
+ {0x8b5e1904, "Give me a rock, paper and scissors and I will move the world. CCFestoon"},
+ {0x7cc6102b, "If the enemy is within range, then so are you."},
+ {0x700318e7, "It's well we cannot hear the screams/That we create in others' dreams."},
+ {0x1e601747, "You remind me of a TV show, but that's all right: I watch it anyway."},
+ {0xb55b0b09, "C is as portable as Stonehedge!!"},
+ {0x39111dd0, "Even if I could be Shakespeare, I think I should still choose to be Faraday. - A. Huxley"},
+ {0x91dd304f, "The fugacity of a constituent in a mixture of gases at a given temperature is proportional to its mole fraction. Lewis-Randall Rule"},
+ {0x2e5d1316, "How can you write a big system without C++? -Paul Glick"},
+ {0xd0201df6, "'Invariant assertions' is the most elegant programming technique! -Tom Szymanski"},
+}
+
+func TestGolden(t *testing.T) {
+ for i := 0; i < len(golden); i++ {
+ g := golden[i]
+ c := New()
+ io.WriteString(c, g.in)
+ s := c.Sum32()
+ if s != g.out {
+ t.Errorf("adler32(%s) = 0x%x want 0x%x", g.in, s, g.out)
+ t.FailNow()
+ }
+ }
+}
diff --git a/libgo/go/hash/crc32/crc32.go b/libgo/go/hash/crc32/crc32.go
new file mode 100644
index 000000000..2ab0c5491
--- /dev/null
+++ b/libgo/go/hash/crc32/crc32.go
@@ -0,0 +1,111 @@
+// 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.
+
+// This package implements the 32-bit cyclic redundancy check, or CRC-32, checksum.
+// See http://en.wikipedia.org/wiki/Cyclic_redundancy_check for information.
+package crc32
+
+import (
+ "hash"
+ "os"
+)
+
+// The size of a CRC-32 checksum in bytes.
+const Size = 4
+
+// Predefined polynomials.
+const (
+ // Far and away the most common CRC-32 polynomial.
+ // Used by ethernet (IEEE 802.3), v.42, fddi, gzip, zip, png, mpeg-2, ...
+ IEEE = 0xedb88320
+
+ // Castagnoli's polynomial, used in iSCSI.
+ // Has better error detection characteristics than IEEE.
+ // http://dx.doi.org/10.1109/26.231911
+ Castagnoli = 0x82f63b78
+
+ // Koopman's polynomial.
+ // Also has better error detection characteristics than IEEE.
+ // http://dx.doi.org/10.1109/DSN.2002.1028931
+ Koopman = 0xeb31d82e
+)
+
+// Table is a 256-word table representing the polynomial for efficient processing.
+type Table [256]uint32
+
+// MakeTable returns the Table constructed from the specified polynomial.
+func MakeTable(poly uint32) *Table {
+ t := new(Table)
+ for i := 0; i < 256; i++ {
+ crc := uint32(i)
+ for j := 0; j < 8; j++ {
+ if crc&1 == 1 {
+ crc = (crc >> 1) ^ poly
+ } else {
+ crc >>= 1
+ }
+ }
+ t[i] = crc
+ }
+ return t
+}
+
+// IEEETable is the table for the IEEE polynomial.
+var IEEETable = MakeTable(IEEE)
+
+// digest represents the partial evaluation of a checksum.
+type digest struct {
+ crc uint32
+ tab *Table
+}
+
+// New creates a new hash.Hash32 computing the CRC-32 checksum
+// using the polynomial represented by the Table.
+func New(tab *Table) hash.Hash32 { return &digest{0, tab} }
+
+// NewIEEE creates a new hash.Hash32 computing the CRC-32 checksum
+// using the IEEE polynomial.
+func NewIEEE() hash.Hash32 { return New(IEEETable) }
+
+func (d *digest) Size() int { return Size }
+
+func (d *digest) Reset() { d.crc = 0 }
+
+func update(crc uint32, tab *Table, p []byte) uint32 {
+ crc = ^crc
+ for _, v := range p {
+ crc = tab[byte(crc)^v] ^ (crc >> 8)
+ }
+ return ^crc
+}
+
+// Update returns the result of adding the bytes in p to the crc.
+func Update(crc uint32, tab *Table, p []byte) uint32 {
+ return update(crc, tab, p)
+}
+
+func (d *digest) Write(p []byte) (n int, err os.Error) {
+ d.crc = update(d.crc, d.tab, p)
+ return len(p), nil
+}
+
+func (d *digest) Sum32() uint32 { return d.crc }
+
+func (d *digest) Sum() []byte {
+ p := make([]byte, 4)
+ s := d.Sum32()
+ p[0] = byte(s >> 24)
+ p[1] = byte(s >> 16)
+ p[2] = byte(s >> 8)
+ p[3] = byte(s)
+ return p
+}
+
+// Checksum returns the CRC-32 checksum of data
+// using the polynomial represented by the Table.
+func Checksum(data []byte, tab *Table) uint32 { return update(0, tab, data) }
+
+// ChecksumIEEE returns the CRC-32 checksum of data
+// using the IEEE polynomial.
+func ChecksumIEEE(data []byte) uint32 { return update(0, IEEETable, data) }
diff --git a/libgo/go/hash/crc32/crc32_test.go b/libgo/go/hash/crc32/crc32_test.go
new file mode 100644
index 000000000..cf5743c99
--- /dev/null
+++ b/libgo/go/hash/crc32/crc32_test.go
@@ -0,0 +1,76 @@
+// 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 crc32
+
+import (
+ "io"
+ "testing"
+)
+
+type test struct {
+ out uint32
+ in string
+}
+
+var golden = []test{
+ {0x0, ""},
+ {0xe8b7be43, "a"},
+ {0x9e83486d, "ab"},
+ {0x352441c2, "abc"},
+ {0xed82cd11, "abcd"},
+ {0x8587d865, "abcde"},
+ {0x4b8e39ef, "abcdef"},
+ {0x312a6aa6, "abcdefg"},
+ {0xaeef2a50, "abcdefgh"},
+ {0x8da988af, "abcdefghi"},
+ {0x3981703a, "abcdefghij"},
+ {0x6b9cdfe7, "Discard medicine more than two years old."},
+ {0xc90ef73f, "He who has a shady past knows that nice guys finish last."},
+ {0xb902341f, "I wouldn't marry him with a ten foot pole."},
+ {0x42080e8, "Free! Free!/A trip/to Mars/for 900/empty jars/Burma Shave"},
+ {0x154c6d11, "The days of the digital watch are numbered. -Tom Stoppard"},
+ {0x4c418325, "Nepal premier won't resign."},
+ {0x33955150, "For every action there is an equal and opposite government program."},
+ {0x26216a4b, "His money is twice tainted: 'taint yours and 'taint mine."},
+ {0x1abbe45e, "There is no reason for any individual to have a computer in their home. -Ken Olsen, 1977"},
+ {0xc89a94f7, "It's a tiny change to the code and not completely disgusting. - Bob Manchek"},
+ {0xab3abe14, "size: a.out: bad magic"},
+ {0xbab102b6, "The major problem is with sendmail. -Mark Horton"},
+ {0x999149d7, "Give me a rock, paper and scissors and I will move the world. CCFestoon"},
+ {0x6d52a33c, "If the enemy is within range, then so are you."},
+ {0x90631e8d, "It's well we cannot hear the screams/That we create in others' dreams."},
+ {0x78309130, "You remind me of a TV show, but that's all right: I watch it anyway."},
+ {0x7d0a377f, "C is as portable as Stonehedge!!"},
+ {0x8c79fd79, "Even if I could be Shakespeare, I think I should still choose to be Faraday. - A. Huxley"},
+ {0xa20b7167, "The fugacity of a constituent in a mixture of gases at a given temperature is proportional to its mole fraction. Lewis-Randall Rule"},
+ {0x8e0bb443, "How can you write a big system without C++? -Paul Glick"},
+}
+
+func TestGolden(t *testing.T) {
+ for i := 0; i < len(golden); i++ {
+ g := golden[i]
+ c := NewIEEE()
+ io.WriteString(c, g.in)
+ s := c.Sum32()
+ if s != g.out {
+ t.Errorf("crc32(%s) = 0x%x want 0x%x", g.in, s, g.out)
+ t.FailNow()
+ }
+ }
+}
+
+func BenchmarkCrc32KB(b *testing.B) {
+ b.StopTimer()
+ data := make([]uint8, 1024)
+ for i := 0; i < 1024; i++ {
+ data[i] = uint8(i)
+ }
+ c := NewIEEE()
+ b.StartTimer()
+
+ for i := 0; i < b.N; i++ {
+ c.Write(data)
+ }
+}
diff --git a/libgo/go/hash/crc64/crc64.go b/libgo/go/hash/crc64/crc64.go
new file mode 100644
index 000000000..844386564
--- /dev/null
+++ b/libgo/go/hash/crc64/crc64.go
@@ -0,0 +1,96 @@
+// 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.
+
+// This package implements the 64-bit cyclic redundancy check, or CRC-64, checksum.
+// See http://en.wikipedia.org/wiki/Cyclic_redundancy_check for information.
+package crc64
+
+import (
+ "hash"
+ "os"
+)
+
+// The size of a CRC-64 checksum in bytes.
+const Size = 8
+
+// Predefined polynomials.
+const (
+ // The ISO polynomial, defined in ISO 3309 and used in HDLC.
+ ISO = 0xD800000000000000
+
+ // The ECMA polynomial, defined in ECMA 182.
+ ECMA = 0xC96C5795D7870F42
+)
+
+// Table is a 256-word table representing the polynomial for efficient processing.
+type Table [256]uint64
+
+// MakeTable returns the Table constructed from the specified polynomial.
+func MakeTable(poly uint64) *Table {
+ t := new(Table)
+ for i := 0; i < 256; i++ {
+ crc := uint64(i)
+ for j := 0; j < 8; j++ {
+ if crc&1 == 1 {
+ crc = (crc >> 1) ^ poly
+ } else {
+ crc >>= 1
+ }
+ }
+ t[i] = crc
+ }
+ return t
+}
+
+// digest represents the partial evaluation of a checksum.
+type digest struct {
+ crc uint64
+ tab *Table
+}
+
+// New creates a new hash.Hash64 computing the CRC-64 checksum
+// using the polynomial represented by the Table.
+func New(tab *Table) hash.Hash64 { return &digest{0, tab} }
+
+func (d *digest) Size() int { return Size }
+
+func (d *digest) Reset() { d.crc = 0 }
+
+func update(crc uint64, tab *Table, p []byte) uint64 {
+ crc = ^crc
+ for _, v := range p {
+ crc = tab[byte(crc)^v] ^ (crc >> 8)
+ }
+ return ^crc
+}
+
+// Update returns the result of adding the bytes in p to the crc.
+func Update(crc uint64, tab *Table, p []byte) uint64 {
+ return update(crc, tab, p)
+}
+
+func (d *digest) Write(p []byte) (n int, err os.Error) {
+ d.crc = update(d.crc, d.tab, p)
+ return len(p), nil
+}
+
+func (d *digest) Sum64() uint64 { return d.crc }
+
+func (d *digest) Sum() []byte {
+ p := make([]byte, 8)
+ s := d.Sum64()
+ p[0] = byte(s >> 56)
+ p[1] = byte(s >> 48)
+ p[2] = byte(s >> 40)
+ p[3] = byte(s >> 32)
+ p[4] = byte(s >> 24)
+ p[5] = byte(s >> 16)
+ p[6] = byte(s >> 8)
+ p[7] = byte(s)
+ return p
+}
+
+// Checksum returns the CRC-64 checksum of data
+// using the polynomial represented by the Table.
+func Checksum(data []byte, tab *Table) uint64 { return update(0, tab, data) }
diff --git a/libgo/go/hash/crc64/crc64_test.go b/libgo/go/hash/crc64/crc64_test.go
new file mode 100644
index 000000000..e932524e0
--- /dev/null
+++ b/libgo/go/hash/crc64/crc64_test.go
@@ -0,0 +1,78 @@
+// 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 crc64
+
+import (
+ "io"
+ "testing"
+)
+
+type test struct {
+ out uint64
+ in string
+}
+
+var golden = []test{
+ {0x0, ""},
+ {0x3420000000000000, "a"},
+ {0x36c4200000000000, "ab"},
+ {0x3776c42000000000, "abc"},
+ {0x336776c420000000, "abcd"},
+ {0x32d36776c4200000, "abcde"},
+ {0x3002d36776c42000, "abcdef"},
+ {0x31b002d36776c420, "abcdefg"},
+ {0xe21b002d36776c4, "abcdefgh"},
+ {0x8b6e21b002d36776, "abcdefghi"},
+ {0x7f5b6e21b002d367, "abcdefghij"},
+ {0x8ec0e7c835bf9cdf, "Discard medicine more than two years old."},
+ {0xc7db1759e2be5ab4, "He who has a shady past knows that nice guys finish last."},
+ {0xfbf9d9603a6fa020, "I wouldn't marry him with a ten foot pole."},
+ {0xeafc4211a6daa0ef, "Free! Free!/A trip/to Mars/for 900/empty jars/Burma Shave"},
+ {0x3e05b21c7a4dc4da, "The days of the digital watch are numbered. -Tom Stoppard"},
+ {0x5255866ad6ef28a6, "Nepal premier won't resign."},
+ {0x8a79895be1e9c361, "For every action there is an equal and opposite government program."},
+ {0x8878963a649d4916, "His money is twice tainted: 'taint yours and 'taint mine."},
+ {0xa7b9d53ea87eb82f, "There is no reason for any individual to have a computer in their home. -Ken Olsen, 1977"},
+ {0xdb6805c0966a2f9c, "It's a tiny change to the code and not completely disgusting. - Bob Manchek"},
+ {0xf3553c65dacdadd2, "size: a.out: bad magic"},
+ {0x9d5e034087a676b9, "The major problem is with sendmail. -Mark Horton"},
+ {0xa6db2d7f8da96417, "Give me a rock, paper and scissors and I will move the world. CCFestoon"},
+ {0x325e00cd2fe819f9, "If the enemy is within range, then so are you."},
+ {0x88c6600ce58ae4c6, "It's well we cannot hear the screams/That we create in others' dreams."},
+ {0x28c4a3f3b769e078, "You remind me of a TV show, but that's all right: I watch it anyway."},
+ {0xa698a34c9d9f1dca, "C is as portable as Stonehedge!!"},
+ {0xf6c1e2a8c26c5cfc, "Even if I could be Shakespeare, I think I should still choose to be Faraday. - A. Huxley"},
+ {0xd402559dfe9b70c, "The fugacity of a constituent in a mixture of gases at a given temperature is proportional to its mole fraction. Lewis-Randall Rule"},
+ {0xdb6efff26aa94946, "How can you write a big system without C++? -Paul Glick"},
+}
+
+var tab = MakeTable(ISO)
+
+func TestGolden(t *testing.T) {
+ for i := 0; i < len(golden); i++ {
+ g := golden[i]
+ c := New(tab)
+ io.WriteString(c, g.in)
+ s := c.Sum64()
+ if s != g.out {
+ t.Errorf("crc64(%s) = 0x%x want 0x%x", g.in, s, g.out)
+ t.FailNow()
+ }
+ }
+}
+
+func BenchmarkCrc64KB(b *testing.B) {
+ b.StopTimer()
+ data := make([]uint8, 1024)
+ for i := 0; i < 1024; i++ {
+ data[i] = uint8(i)
+ }
+ c := New(tab)
+ b.StartTimer()
+
+ for i := 0; i < b.N; i++ {
+ c.Write(data)
+ }
+}
diff --git a/libgo/go/hash/hash.go b/libgo/go/hash/hash.go
new file mode 100644
index 000000000..56ac259db
--- /dev/null
+++ b/libgo/go/hash/hash.go
@@ -0,0 +1,36 @@
+// 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
+
+import "io"
+
+// Hash is the common interface implemented by all hash functions.
+type Hash interface {
+ // Write adds more data to the running hash.
+ // It never returns an error.
+ io.Writer
+
+ // Sum returns the current hash, without changing the
+ // underlying hash state.
+ Sum() []byte
+
+ // Reset resets the hash to one with zero bytes written.
+ Reset()
+
+ // Size returns the number of bytes Sum will return.
+ Size() 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
+}