Adding upstream version 1.16.10.upstream/1.16.10upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

2 files changed, 417 insertions, 0 deletions

diff --git a/src/hash/crc64/crc64.go b/src/hash/crc64/crc64.go
new file mode 100644
index 0000000..063c63c
--- /dev/null
+++ b/src/hash/crc64/crc64.go
@@ -0,0 +1,224 @@
+// 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 implements the 64-bit cyclic redundancy check, or CRC-64,
+// checksum. See https://en.wikipedia.org/wiki/Cyclic_redundancy_check for
+// information.
+package crc64
+
+import (
+	"errors"
+	"hash"
+	"sync"
+)
+
+// 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
+
+var (
+	slicing8TablesBuildOnce sync.Once
+	slicing8TableISO        *[8]Table
+	slicing8TableECMA       *[8]Table
+)
+
+func buildSlicing8TablesOnce() {
+	slicing8TablesBuildOnce.Do(buildSlicing8Tables)
+}
+
+func buildSlicing8Tables() {
+	slicing8TableISO = makeSlicingBy8Table(makeTable(ISO))
+	slicing8TableECMA = makeSlicingBy8Table(makeTable(ECMA))
+}
+
+// MakeTable returns a Table constructed from the specified polynomial.
+// The contents of this Table must not be modified.
+func MakeTable(poly uint64) *Table {
+	buildSlicing8TablesOnce()
+	switch poly {
+	case ISO:
+		return &slicing8TableISO[0]
+	case ECMA:
+		return &slicing8TableECMA[0]
+	default:
+		return makeTable(poly)
+	}
+}
+
+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
+}
+
+func makeSlicingBy8Table(t *Table) *[8]Table {
+	var helperTable [8]Table
+	helperTable[0] = *t
+	for i := 0; i < 256; i++ {
+		crc := t[i]
+		for j := 1; j < 8; j++ {
+			crc = t[crc&0xff] ^ (crc >> 8)
+			helperTable[j][i] = crc
+		}
+	}
+	return &helperTable
+}
+
+// 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. Its Sum method will lay the
+// value out in big-endian byte order. The returned Hash64 also
+// implements encoding.BinaryMarshaler and encoding.BinaryUnmarshaler to
+// marshal and unmarshal the internal state of the hash.
+func New(tab *Table) hash.Hash64 { return &digest{0, tab} }
+
+func (d *digest) Size() int { return Size }
+
+func (d *digest) BlockSize() int { return 1 }
+
+func (d *digest) Reset() { d.crc = 0 }
+
+const (
+	magic         = "crc\x02"
+	marshaledSize = len(magic) + 8 + 8
+)
+
+func (d *digest) MarshalBinary() ([]byte, error) {
+	b := make([]byte, 0, marshaledSize)
+	b = append(b, magic...)
+	b = appendUint64(b, tableSum(d.tab))
+	b = appendUint64(b, d.crc)
+	return b, nil
+}
+
+func (d *digest) UnmarshalBinary(b []byte) error {
+	if len(b) < len(magic) || string(b[:len(magic)]) != magic {
+		return errors.New("hash/crc64: invalid hash state identifier")
+	}
+	if len(b) != marshaledSize {
+		return errors.New("hash/crc64: invalid hash state size")
+	}
+	if tableSum(d.tab) != readUint64(b[4:]) {
+		return errors.New("hash/crc64: tables do not match")
+	}
+	d.crc = readUint64(b[12:])
+	return nil
+}
+
+func appendUint64(b []byte, x uint64) []byte {
+	a := [8]byte{
+		byte(x >> 56),
+		byte(x >> 48),
+		byte(x >> 40),
+		byte(x >> 32),
+		byte(x >> 24),
+		byte(x >> 16),
+		byte(x >> 8),
+		byte(x),
+	}
+	return append(b, a[:]...)
+}
+
+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
+}
+
+func update(crc uint64, tab *Table, p []byte) uint64 {
+	buildSlicing8TablesOnce()
+	crc = ^crc
+	// Table comparison is somewhat expensive, so avoid it for small sizes
+	for len(p) >= 64 {
+		var helperTable *[8]Table
+		if *tab == slicing8TableECMA[0] {
+			helperTable = slicing8TableECMA
+		} else if *tab == slicing8TableISO[0] {
+			helperTable = slicing8TableISO
+			// For smaller sizes creating extended table takes too much time
+		} else if len(p) > 16384 {
+			helperTable = makeSlicingBy8Table(tab)
+		} else {
+			break
+		}
+		// Update using slicing-by-8
+		for len(p) > 8 {
+			crc ^= uint64(p[0]) | uint64(p[1])<<8 | uint64(p[2])<<16 | uint64(p[3])<<24 |
+				uint64(p[4])<<32 | uint64(p[5])<<40 | uint64(p[6])<<48 | uint64(p[7])<<56
+			crc = helperTable[7][crc&0xff] ^
+				helperTable[6][(crc>>8)&0xff] ^
+				helperTable[5][(crc>>16)&0xff] ^
+				helperTable[4][(crc>>24)&0xff] ^
+				helperTable[3][(crc>>32)&0xff] ^
+				helperTable[2][(crc>>40)&0xff] ^
+				helperTable[1][(crc>>48)&0xff] ^
+				helperTable[0][crc>>56]
+			p = p[8:]
+		}
+	}
+	// For reminders or small sizes
+	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 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(in []byte) []byte {
+	s := d.Sum64()
+	return append(in, byte(s>>56), byte(s>>48), byte(s>>40), byte(s>>32), byte(s>>24), byte(s>>16), byte(s>>8), byte(s))
+}
+
+// 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) }
+
+// tableSum returns the ISO checksum of table t.
+func tableSum(t *Table) uint64 {
+	var a [2048]byte
+	b := a[:0]
+	if t != nil {
+		for _, x := range t {
+			b = appendUint64(b, x)
+		}
+	}
+	return Checksum(b, MakeTable(ISO))
+}
diff --git a/src/hash/crc64/crc64_test.go b/src/hash/crc64/crc64_test.go
new file mode 100644
index 0000000..9cf602c
--- /dev/null
+++ b/src/hash/crc64/crc64_test.go
@@ -0,0 +1,193 @@
+// 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 (
+	"encoding"
+	"io"
+	"testing"
+)
+
+type test struct {
+	outISO        uint64
+	outECMA       uint64
+	in            string
+	halfStateISO  string // ISO marshaled hash state after first half of in written, used by TestGoldenMarshal
+	halfStateECMA string // ECMA marshaled hash state after first half of in written, used by TestGoldenMarshal
+}
+
+var golden = []test{
+	{0x0, 0x0, "", "crc\x02s\xba\x84\x84\xbb\xcd]\xef\x00\x00\x00\x00\x00\x00\x00\x00", "crc\x02`&\x9aR\xe1\xb7\xfee\x00\x00\x00\x00\x00\x00\x00\x00"},
+	{0x3420000000000000, 0x330284772e652b05, "a", "crc\x02s\xba\x84\x84\xbb\xcd]\xef\x00\x00\x00\x00\x00\x00\x00\x00", "crc\x02`&\x9aR\xe1\xb7\xfee\x00\x00\x00\x00\x00\x00\x00\x00"},
+	{0x36c4200000000000, 0xbc6573200e84b046, "ab", "crc\x02s\xba\x84\x84\xbb\xcd]\xef4 \x00\x00\x00\x00\x00\x00", "crc\x02`&\x9aR\xe1\xb7\xfee3\x02\x84w.e+\x05"},
+	{0x3776c42000000000, 0x2cd8094a1a277627, "abc", "crc\x02s\xba\x84\x84\xbb\xcd]\xef4 \x00\x00\x00\x00\x00\x00", "crc\x02`&\x9aR\xe1\xb7\xfee3\x02\x84w.e+\x05"},
+	{0x336776c420000000, 0x3c9d28596e5960ba, "abcd", "crc\x02s\xba\x84\x84\xbb\xcd]\xef6\xc4 \x00\x00\x00\x00\x00", "crc\x02`&\x9aR\xe1\xb7\xfee\xbces \x0e\x84\xb0F"},
+	{0x32d36776c4200000, 0x40bdf58fb0895f2, "abcde", "crc\x02s\xba\x84\x84\xbb\xcd]\xef6\xc4 \x00\x00\x00\x00\x00", "crc\x02`&\x9aR\xe1\xb7\xfee\xbces \x0e\x84\xb0F"},
+	{0x3002d36776c42000, 0xd08e9f8545a700f4, "abcdef", "crc\x02s\xba\x84\x84\xbb\xcd]\xef7v\xc4 \x00\x00\x00\x00", "crc\x02`&\x9aR\xe1\xb7\xfee,\xd8\tJ\x1a'v'"},
+	{0x31b002d36776c420, 0xec20a3a8cc710e66, "abcdefg", "crc\x02s\xba\x84\x84\xbb\xcd]\xef7v\xc4 \x00\x00\x00\x00", "crc\x02`&\x9aR\xe1\xb7\xfee,\xd8\tJ\x1a'v'"},
+	{0xe21b002d36776c4, 0x67b4f30a647a0c59, "abcdefgh", "crc\x02s\xba\x84\x84\xbb\xcd]\xef3gv\xc4 \x00\x00\x00", "crc\x02`&\x9aR\xe1\xb7\xfee<\x9d(YnY`\xba"},
+	{0x8b6e21b002d36776, 0x9966f6c89d56ef8e, "abcdefghi", "crc\x02s\xba\x84\x84\xbb\xcd]\xef3gv\xc4 \x00\x00\x00", "crc\x02`&\x9aR\xe1\xb7\xfee<\x9d(YnY`\xba"},
+	{0x7f5b6e21b002d367, 0x32093a2ecd5773f4, "abcdefghij", "crc\x02s\xba\x84\x84\xbb\xcd]\xef2\xd3gv\xc4 \x00\x00", "crc\x02`&\x9aR\xe1\xb7\xfee\x04\v\xdfX\xfb\b\x95\xf2"},
+	{0x8ec0e7c835bf9cdf, 0x8a0825223ea6d221, "Discard medicine more than two years old.", "crc\x02s\xba\x84\x84\xbb\xcd]\xef\xc6\xc0\f\xac'\x11\x12\xd5", "crc\x02`&\x9aR\xe1\xb7\xfee\xfd%\xc0&\xa0R\xef\x95"},
+	{0xc7db1759e2be5ab4, 0x8562c0ac2ab9a00d, "He who has a shady past knows that nice guys finish last.", "crc\x02s\xba\x84\x84\xbb\xcd]\xef\t\xcb\xd15X[r\t", "crc\x02`&\x9aR\xe1\xb7\xfee\a\x02\xe8|+\xc1\x06\xe3"},
+	{0xfbf9d9603a6fa020, 0x3ee2a39c083f38b4, "I wouldn't marry him with a ten foot pole.", "crc\x02s\xba\x84\x84\xbb\xcd]\xef\x19\xc8d\xbe\x84\x14\x87_", "crc\x02`&\x9aR\xe1\xb7\xfee˷\xd3\xeeG\xdcE\x8c"},
+	{0xeafc4211a6daa0ef, 0x1f603830353e518a, "Free! Free!/A trip/to Mars/for 900/empty jars/Burma Shave", "crc\x02s\xba\x84\x84\xbb\xcd]\xef\xad\x1b*\xc0\xb1\xf3i(", "crc\x02`&\x9aR\xe1\xb7\xfee\xa7\x8a\xdb\xf6\xd2R\t\x96"},
+	{0x3e05b21c7a4dc4da, 0x2fd681d7b2421fd, "The days of the digital watch are numbered.  -Tom Stoppard", "crc\x02s\xba\x84\x84\xbb\xcd]\xefv78\x1ak\x02\x8f\xff", "crc\x02`&\x9aR\xe1\xb7\xfeeT\xcbl\x10\xfb\x87K*"},
+	{0x5255866ad6ef28a6, 0x790ef2b16a745a41, "Nepal premier won't resign.", "crc\x02s\xba\x84\x84\xbb\xcd]\xef\xcbf\x11R\xbfh\xde\xc9", "crc\x02`&\x9aR\xe1\xb7\xfee6\x13ُ\x06_\xbd\x9a"},
+	{0x8a79895be1e9c361, 0x3ef8f06daccdcddf, "For every action there is an equal and opposite government program.", "crc\x02s\xba\x84\x84\xbb\xcd]\xef\xf3pV\x01c_Wu", "crc\x02`&\x9aR\xe1\xb7\xfee\xe7\xc6\n\b\x12FL\xa0"},
+	{0x8878963a649d4916, 0x49e41b2660b106d, "His money is twice tainted: 'taint yours and 'taint mine.", "crc\x02s\xba\x84\x84\xbb\xcd]\xefñ\xff\xf1\xe0/Δ", "crc\x02`&\x9aR\xe1\xb7\xfeeOL/\xb1\xec\xa2\x14\x87"},
+	{0xa7b9d53ea87eb82f, 0x561cc0cfa235ac68, "There is no reason for any individual to have a computer in their home. -Ken Olsen, 1977", "crc\x02s\xba\x84\x84\xbb\xcd]\xefݸa\xe1\xb5\xf8\xb9W", "crc\x02`&\x9aR\xe1\xb7\xfee\x87)GQ\x03\xf4K\t"},
+	{0xdb6805c0966a2f9c, 0xd4fe9ef082e69f59, "It's a tiny change to the code and not completely disgusting. - Bob Manchek", "crc\x02s\xba\x84\x84\xbb\xcd]\xefV\xba\x12\x91\x81\x1fNU", "crc\x02`&\x9aR\xe1\xb7\xfee\n\xb8\x81v?\xdeL\xcb"},
+	{0xf3553c65dacdadd2, 0xe3b5e46cd8d63a4d, "size:  a.out:  bad magic", "crc\x02s\xba\x84\x84\xbb\xcd]\xefG\xad\xbc\xb2\xa8y\xc9\xdc", "crc\x02`&\x9aR\xe1\xb7\xfee\xcc\xce\xe5\xe6\x89p\x01\xb8"},
+	{0x9d5e034087a676b9, 0x865aaf6b94f2a051, "The major problem is with sendmail.  -Mark Horton", "crc\x02s\xba\x84\x84\xbb\xcd]\uf8acn\x8aT;&\xd5", "crc\x02`&\x9aR\xe1\xb7\xfeeFf\x9c\x1f\xc9x\xbfa"},
+	{0xa6db2d7f8da96417, 0x7eca10d2f8136eb4, "Give me a rock, paper and scissors and I will move the world.  CCFestoon", "crc\x02s\xba\x84\x84\xbb\xcd]\xef\xeb\x18\xbf\xf9}\x91\xe5|", "crc\x02`&\x9aR\xe1\xb7\xfeea\x9e\x05:\xce[\xe7\x19"},
+	{0x325e00cd2fe819f9, 0xd7dd118c98e98727, "If the enemy is within range, then so are you.", "crc\x02s\xba\x84\x84\xbb\xcd]\xef^5k\xd0Aj_{", "crc\x02`&\x9aR\xe1\xb7\xfee\v#\x99\xa8r\x83YR"},
+	{0x88c6600ce58ae4c6, 0x70fb33c119c29318, "It's well we cannot hear the screams/That we create in others' dreams.", "crc\x02s\xba\x84\x84\xbb\xcd]\xef|\xb5\x02\xdcw\x18/\x86", "crc\x02`&\x9aR\xe1\xb7\xfee]\x9d-\xed\x8c\xf9r9"},
+	{0x28c4a3f3b769e078, 0x57c891e39a97d9b7, "You remind me of a TV show, but that's all right: I watch it anyway.", "crc\x02s\xba\x84\x84\xbb\xcd]\xef\x03\x8bd\x1c\xb0_\x16\x98", "crc\x02`&\x9aR\xe1\xb7\xfee\xafW\x98\xaa\"\xe7\xd7|"},
+	{0xa698a34c9d9f1dca, 0xa1f46ba20ad06eb7, "C is as portable as Stonehedge!!", "crc\x02s\xba\x84\x84\xbb\xcd]\xef.P\xe1I\xc6pi\xdc", "crc\x02`&\x9aR\xe1\xb7\xfee֚\x06\x01(\xc0\x1e\x8b"},
+	{0xf6c1e2a8c26c5cfc, 0x7ad25fafa1710407, "Even if I could be Shakespeare, I think I should still choose to be Faraday. - A. Huxley", "crc\x02s\xba\x84\x84\xbb\xcd]\xef\xf7\xa04\x8a\xf2o\xe0;", "crc\x02`&\x9aR\xe1\xb7\xfee<[\xd2%\x9em\x94\x04"},
+	{0xd402559dfe9b70c, 0x73cef1666185c13f, "The fugacity of a constituent in a mixture of gases at a given temperature is proportional to its mole fraction.  Lewis-Randall Rule", "crc\x02s\xba\x84\x84\xbb\xcd]\xef\u007f\xae\xb9\xbaX=\x19v", "crc\x02`&\x9aR\xe1\xb7\xfee\xb2˦Y\xc5\xd0G\x03"},
+	{0xdb6efff26aa94946, 0xb41858f73c389602, "How can you write a big system without C++?  -Paul Glick", "crc\x02s\xba\x84\x84\xbb\xcd]\xefa\xed$js\xb9\xa5A", "crc\x02`&\x9aR\xe1\xb7\xfeeZm\x96\x8a\xe2\xaf\x13p"},
+	{0xe7fcf1006b503b61, 0x27db187fc15bbc72, "This is a test of the emergency broadcast system.", "crc\x02s\xba\x84\x84\xbb\xcd]\xef}\xee[q\x16\xcb\xe4\x8d", "crc\x02`&\x9aR\xe1\xb7\xfee\xb1\x93] \xeb\xa9am"},
+}
+
+func TestGolden(t *testing.T) {
+	tabISO := MakeTable(ISO)
+	tabECMA := MakeTable(ECMA)
+	for i := 0; i < len(golden); i++ {
+		g := golden[i]
+		c := New(tabISO)
+		io.WriteString(c, g.in)
+		s := c.Sum64()
+		if s != g.outISO {
+			t.Fatalf("ISO crc64(%s) = 0x%x want 0x%x", g.in, s, g.outISO)
+		}
+		c = New(tabECMA)
+		io.WriteString(c, g.in)
+		s = c.Sum64()
+		if s != g.outECMA {
+			t.Fatalf("ECMA crc64(%s) = 0x%x want 0x%x", g.in, s, g.outECMA)
+		}
+	}
+}
+
+func TestGoldenMarshal(t *testing.T) {
+	t.Run("ISO", func(t *testing.T) {
+		table := MakeTable(ISO)
+		for _, g := range golden {
+			h := New(table)
+			h2 := New(table)
+
+			io.WriteString(h, g.in[:len(g.in)/2])
+
+			state, err := h.(encoding.BinaryMarshaler).MarshalBinary()
+			if err != nil {
+				t.Errorf("could not marshal: %v", err)
+				continue
+			}
+
+			if string(state) != g.halfStateISO {
+				t.Errorf("ISO crc64(%q) state = %q, want %q", g.in, state, g.halfStateISO)
+				continue
+			}
+
+			if err := h2.(encoding.BinaryUnmarshaler).UnmarshalBinary(state); err != nil {
+				t.Errorf("could not unmarshal: %v", err)
+				continue
+			}
+
+			io.WriteString(h, g.in[len(g.in)/2:])
+			io.WriteString(h2, g.in[len(g.in)/2:])
+
+			if h.Sum64() != h2.Sum64() {
+				t.Errorf("ISO crc64(%s) = 0x%x != marshaled (0x%x)", g.in, h.Sum64(), h2.Sum64())
+			}
+		}
+	})
+	t.Run("ECMA", func(t *testing.T) {
+		table := MakeTable(ECMA)
+		for _, g := range golden {
+			h := New(table)
+			h2 := New(table)
+
+			io.WriteString(h, g.in[:len(g.in)/2])
+
+			state, err := h.(encoding.BinaryMarshaler).MarshalBinary()
+			if err != nil {
+				t.Errorf("could not marshal: %v", err)
+				continue
+			}
+
+			if string(state) != g.halfStateECMA {
+				t.Errorf("ECMA crc64(%q) state = %q, want %q", g.in, state, g.halfStateECMA)
+				continue
+			}
+
+			if err := h2.(encoding.BinaryUnmarshaler).UnmarshalBinary(state); err != nil {
+				t.Errorf("could not unmarshal: %v", err)
+				continue
+			}
+
+			io.WriteString(h, g.in[len(g.in)/2:])
+			io.WriteString(h2, g.in[len(g.in)/2:])
+
+			if h.Sum64() != h2.Sum64() {
+				t.Errorf("ECMA crc64(%s) = 0x%x != marshaled (0x%x)", g.in, h.Sum64(), h2.Sum64())
+			}
+		}
+	})
+}
+
+func TestMarshalTableMismatch(t *testing.T) {
+	h1 := New(MakeTable(ISO))
+	h2 := New(MakeTable(ECMA))
+
+	state1, err := h1.(encoding.BinaryMarshaler).MarshalBinary()
+	if err != nil {
+		t.Errorf("could not marshal: %v", err)
+	}
+
+	if err := h2.(encoding.BinaryUnmarshaler).UnmarshalBinary(state1); err == nil {
+		t.Errorf("no error when one was expected")
+	}
+}
+
+func bench(b *testing.B, poly uint64, size int64) {
+	b.SetBytes(size)
+	data := make([]byte, size)
+	for i := range data {
+		data[i] = byte(i)
+	}
+	h := New(MakeTable(poly))
+	in := make([]byte, 0, h.Size())
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		h.Reset()
+		h.Write(data)
+		h.Sum(in)
+	}
+}
+
+func BenchmarkCrc64(b *testing.B) {
+	b.Run("ISO64KB", func(b *testing.B) {
+		bench(b, ISO, 64<<10)
+	})
+	b.Run("ISO4KB", func(b *testing.B) {
+		bench(b, ISO, 4<<10)
+	})
+	b.Run("ISO1KB", func(b *testing.B) {
+		bench(b, ISO, 1<<10)
+	})
+	b.Run("ECMA64KB", func(b *testing.B) {
+		bench(b, ECMA, 64<<10)
+	})
+	b.Run("Random64KB", func(b *testing.B) {
+		bench(b, 0x777, 64<<10)
+	})
+	b.Run("Random16KB", func(b *testing.B) {
+		bench(b, 0x777, 16<<10)
+	})
+}