VOL-1868 move simulated onu from voltha-go to voltha-simonu-adapter

Sourced from voltha-go commit 251a11c0ffe60512318a644cd6ce0dc4e12f4018

Change-Id: Iab179bc2f3dd772ed7f488d1c03d1a84ba75e874
diff --git a/vendor/github.com/pierrec/lz4/internal/xxh32/xxh32zero.go b/vendor/github.com/pierrec/lz4/internal/xxh32/xxh32zero.go
new file mode 100644
index 0000000..850a6fd
--- /dev/null
+++ b/vendor/github.com/pierrec/lz4/internal/xxh32/xxh32zero.go
@@ -0,0 +1,222 @@
+// Package xxh32 implements the very fast XXH hashing algorithm (32 bits version).
+// (https://github.com/Cyan4973/XXH/)
+package xxh32
+
+import (
+	"encoding/binary"
+)
+
+const (
+	prime32_1 uint32 = 2654435761
+	prime32_2 uint32 = 2246822519
+	prime32_3 uint32 = 3266489917
+	prime32_4 uint32 = 668265263
+	prime32_5 uint32 = 374761393
+
+	prime32_1plus2 uint32 = 606290984
+	prime32_minus1 uint32 = 1640531535
+)
+
+// XXHZero represents an xxhash32 object with seed 0.
+type XXHZero struct {
+	v1       uint32
+	v2       uint32
+	v3       uint32
+	v4       uint32
+	totalLen uint64
+	buf      [16]byte
+	bufused  int
+}
+
+// Sum appends the current hash to b and returns the resulting slice.
+// It does not change the underlying hash state.
+func (xxh XXHZero) Sum(b []byte) []byte {
+	h32 := xxh.Sum32()
+	return append(b, byte(h32), byte(h32>>8), byte(h32>>16), byte(h32>>24))
+}
+
+// Reset resets the Hash to its initial state.
+func (xxh *XXHZero) Reset() {
+	xxh.v1 = prime32_1plus2
+	xxh.v2 = prime32_2
+	xxh.v3 = 0
+	xxh.v4 = prime32_minus1
+	xxh.totalLen = 0
+	xxh.bufused = 0
+}
+
+// Size returns the number of bytes returned by Sum().
+func (xxh *XXHZero) Size() int {
+	return 4
+}
+
+// BlockSize gives the minimum number of bytes accepted by Write().
+func (xxh *XXHZero) BlockSize() int {
+	return 1
+}
+
+// Write adds input bytes to the Hash.
+// It never returns an error.
+func (xxh *XXHZero) Write(input []byte) (int, error) {
+	if xxh.totalLen == 0 {
+		xxh.Reset()
+	}
+	n := len(input)
+	m := xxh.bufused
+
+	xxh.totalLen += uint64(n)
+
+	r := len(xxh.buf) - m
+	if n < r {
+		copy(xxh.buf[m:], input)
+		xxh.bufused += len(input)
+		return n, nil
+	}
+
+	p := 0
+	// Causes compiler to work directly from registers instead of stack:
+	v1, v2, v3, v4 := xxh.v1, xxh.v2, xxh.v3, xxh.v4
+	if m > 0 {
+		// some data left from previous update
+		copy(xxh.buf[xxh.bufused:], input[:r])
+		xxh.bufused += len(input) - r
+
+		// fast rotl(13)
+		buf := xxh.buf[:16] // BCE hint.
+		v1 = rol13(v1+binary.LittleEndian.Uint32(buf[:])*prime32_2) * prime32_1
+		v2 = rol13(v2+binary.LittleEndian.Uint32(buf[4:])*prime32_2) * prime32_1
+		v3 = rol13(v3+binary.LittleEndian.Uint32(buf[8:])*prime32_2) * prime32_1
+		v4 = rol13(v4+binary.LittleEndian.Uint32(buf[12:])*prime32_2) * prime32_1
+		p = r
+		xxh.bufused = 0
+	}
+
+	for n := n - 16; p <= n; p += 16 {
+		sub := input[p:][:16] //BCE hint for compiler
+		v1 = rol13(v1+binary.LittleEndian.Uint32(sub[:])*prime32_2) * prime32_1
+		v2 = rol13(v2+binary.LittleEndian.Uint32(sub[4:])*prime32_2) * prime32_1
+		v3 = rol13(v3+binary.LittleEndian.Uint32(sub[8:])*prime32_2) * prime32_1
+		v4 = rol13(v4+binary.LittleEndian.Uint32(sub[12:])*prime32_2) * prime32_1
+	}
+	xxh.v1, xxh.v2, xxh.v3, xxh.v4 = v1, v2, v3, v4
+
+	copy(xxh.buf[xxh.bufused:], input[p:])
+	xxh.bufused += len(input) - p
+
+	return n, nil
+}
+
+// Sum32 returns the 32 bits Hash value.
+func (xxh *XXHZero) Sum32() uint32 {
+	h32 := uint32(xxh.totalLen)
+	if h32 >= 16 {
+		h32 += rol1(xxh.v1) + rol7(xxh.v2) + rol12(xxh.v3) + rol18(xxh.v4)
+	} else {
+		h32 += prime32_5
+	}
+
+	p := 0
+	n := xxh.bufused
+	buf := xxh.buf
+	for n := n - 4; p <= n; p += 4 {
+		h32 += binary.LittleEndian.Uint32(buf[p:p+4]) * prime32_3
+		h32 = rol17(h32) * prime32_4
+	}
+	for ; p < n; p++ {
+		h32 += uint32(buf[p]) * prime32_5
+		h32 = rol11(h32) * prime32_1
+	}
+
+	h32 ^= h32 >> 15
+	h32 *= prime32_2
+	h32 ^= h32 >> 13
+	h32 *= prime32_3
+	h32 ^= h32 >> 16
+
+	return h32
+}
+
+// ChecksumZero returns the 32bits Hash value.
+func ChecksumZero(input []byte) uint32 {
+	n := len(input)
+	h32 := uint32(n)
+
+	if n < 16 {
+		h32 += prime32_5
+	} else {
+		v1 := prime32_1plus2
+		v2 := prime32_2
+		v3 := uint32(0)
+		v4 := prime32_minus1
+		p := 0
+		for n := n - 16; p <= n; p += 16 {
+			sub := input[p:][:16] //BCE hint for compiler
+			v1 = rol13(v1+binary.LittleEndian.Uint32(sub[:])*prime32_2) * prime32_1
+			v2 = rol13(v2+binary.LittleEndian.Uint32(sub[4:])*prime32_2) * prime32_1
+			v3 = rol13(v3+binary.LittleEndian.Uint32(sub[8:])*prime32_2) * prime32_1
+			v4 = rol13(v4+binary.LittleEndian.Uint32(sub[12:])*prime32_2) * prime32_1
+		}
+		input = input[p:]
+		n -= p
+		h32 += rol1(v1) + rol7(v2) + rol12(v3) + rol18(v4)
+	}
+
+	p := 0
+	for n := n - 4; p <= n; p += 4 {
+		h32 += binary.LittleEndian.Uint32(input[p:p+4]) * prime32_3
+		h32 = rol17(h32) * prime32_4
+	}
+	for p < n {
+		h32 += uint32(input[p]) * prime32_5
+		h32 = rol11(h32) * prime32_1
+		p++
+	}
+
+	h32 ^= h32 >> 15
+	h32 *= prime32_2
+	h32 ^= h32 >> 13
+	h32 *= prime32_3
+	h32 ^= h32 >> 16
+
+	return h32
+}
+
+// Uint32Zero hashes x with seed 0.
+func Uint32Zero(x uint32) uint32 {
+	h := prime32_5 + 4 + x*prime32_3
+	h = rol17(h) * prime32_4
+	h ^= h >> 15
+	h *= prime32_2
+	h ^= h >> 13
+	h *= prime32_3
+	h ^= h >> 16
+	return h
+}
+
+func rol1(u uint32) uint32 {
+	return u<<1 | u>>31
+}
+
+func rol7(u uint32) uint32 {
+	return u<<7 | u>>25
+}
+
+func rol11(u uint32) uint32 {
+	return u<<11 | u>>21
+}
+
+func rol12(u uint32) uint32 {
+	return u<<12 | u>>20
+}
+
+func rol13(u uint32) uint32 {
+	return u<<13 | u>>19
+}
+
+func rol17(u uint32) uint32 {
+	return u<<17 | u>>15
+}
+
+func rol18(u uint32) uint32 {
+	return u<<18 | u>>14
+}