--- /dev/null
+#pragma once
+#include <array>
+#include <cstdint>
+#include <cstring>
+#include <string>
+#include <type_traits>
+#include <vector>
+
+#include <iostream>
+
+/*
+xxHash - Extremely Fast Hash algorithm
+Header File
+Copyright (C) 2012-2018, Yann Collet.
+Copyright (C) 2017-2018, Piotr Pliszka.
+All rights reserved.
+
+BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+* Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+* Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+You can contact the author at :
+- xxHash source repository : https://github.com/Cyan4973/xxHash
+- xxHash C++ port repository : https://github.com/RedSpah/xxhash_cpp
+*/
+
+/* *************************************
+ * Tuning parameters
+ ***************************************/
+/*!XXH_FORCE_MEMORY_ACCESS :
+ * By default, access to unaligned memory is controlled by `memcpy()`, which is safe and portable.
+ * Unfortunately, on some target/compiler combinations, the generated assembly is sub-optimal.
+ * The below switch allow to select different access method for improved performance.
+ * Method 0 (default) : use `memcpy()`. Safe and portable.
+ * Method 1 : `__packed` statement. It depends on compiler extension (ie, not portable).
+ * This method is safe if your compiler supports it, and *generally* as fast or faster than `memcpy`.
+ * Method 2 : direct access. This method doesn't depend on compiler but violate C standard.
+ * It can generate buggy code on targets which do not support unaligned memory accesses.
+ * But in some circumstances, it's the only known way to get the most performance (ie GCC + ARMv6)
+ * See http://stackoverflow.com/a/32095106/646947 for details.
+ * Prefer these methods in priority order (0 > 1 > 2)
+ */
+#ifndef XXH_FORCE_MEMORY_ACCESS /* can be defined externally, on command line for example */
+#if defined(__GNUC__) && (defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) || defined(__ARM_ARCH_6K__) || \
+ defined(__ARM_ARCH_6Z__) || defined(__ARM_ARCH_6ZK__) || defined(__ARM_ARCH_6T2__))
+#define XXH_FORCE_MEMORY_ACCESS 2
+#elif defined(__INTEL_COMPILER) || \
+ (defined(__GNUC__) && (defined(__ARM_ARCH_7__) || defined(__ARM_ARCH_7A__) || defined(__ARM_ARCH_7R__) || \
+ defined(__ARM_ARCH_7M__) || defined(__ARM_ARCH_7S__)))
+#define XXH_FORCE_MEMORY_ACCESS 1
+#endif
+#endif
+
+/*!XXH_FORCE_NATIVE_FORMAT :
+ * By default, xxHash library provides endian-independent Hash values, based on little-endian convention.
+ * Results are therefore identical for little-endian and big-endian CPU.
+ * This comes at a performance cost for big-endian CPU, since some swapping is required to emulate little-endian format.
+ * Should endian-independence be of no importance for your application, you may set the #define below to 1,
+ * to improve speed for Big-endian CPU.
+ * This option has no impact on Little_Endian CPU.
+ */
+#if !defined(XXH_FORCE_NATIVE_FORMAT) || (XXH_FORCE_NATIVE_FORMAT == 0) /* can be defined externally */
+#define XXH_FORCE_NATIVE_FORMAT 0
+#define XXH_CPU_LITTLE_ENDIAN 1
+#endif
+
+/*!XXH_FORCE_ALIGN_CHECK :
+ * This is a minor performance trick, only useful with lots of very small keys.
+ * It means : check for aligned/unaligned input.
+ * The check costs one initial branch per hash;
+ * set it to 0 when the input is guaranteed to be aligned,
+ * or when alignment doesn't matter for performance.
+ */
+#ifndef XXH_FORCE_ALIGN_CHECK /* can be defined externally */
+#if defined(__i386) || defined(_M_IX86) || defined(__x86_64__) || defined(_M_X64)
+#define XXH_FORCE_ALIGN_CHECK 0
+#else
+#define XXH_FORCE_ALIGN_CHECK 1
+#endif
+#endif
+
+/*!XXH_CPU_LITTLE_ENDIAN :
+ * This is a CPU endian detection macro, will be
+ * automatically set to 1 (little endian) if XXH_FORCE_NATIVE_FORMAT
+ * is left undefined, XXH_FORCE_NATIVE_FORMAT is defined to 0, or if an x86/x86_64 compiler macro is defined.
+ * If left undefined, endianness will be determined at runtime, at the cost of a slight one-time overhead
+ * and a larger overhead due to get_endian() not being constexpr.
+ */
+#ifndef XXH_CPU_LITTLE_ENDIAN
+#if defined(__i386) || defined(_M_IX86) || defined(__x86_64__) || defined(_M_X64)
+#define XXH_CPU_LITTLE_ENDIAN 1
+#endif
+#endif
+
+/* *************************************
+ * Compiler Specific Options
+ ***************************************/
+#define XXH_GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__)
+
+namespace xxh {
+/* *************************************
+ * Version
+ ***************************************/
+constexpr int cpp_version_major = 0;
+constexpr int cpp_version_minor = 6;
+constexpr int cpp_version_release = 5;
+constexpr uint32_t version_number()
+{
+ return cpp_version_major * 10000 + cpp_version_minor * 100 + cpp_version_release;
+}
+
+namespace hash_t_impl {
+/* *************************************
+ * Basic Types - Detail
+ ***************************************/
+
+using _hash32_underlying = uint32_t;
+using _hash64_underlying = uint64_t;
+
+template <size_t N> struct hash_type {
+ using type = void;
+};
+template <> struct hash_type<32> {
+ using type = _hash32_underlying;
+};
+template <> struct hash_type<64> {
+ using type = _hash64_underlying;
+};
+} // namespace hash_t_impl
+
+/* *************************************
+ * Basic Types - Public
+ ***************************************/
+
+template <size_t N> using hash_t = typename hash_t_impl::hash_type<N>::type;
+using hash32_t = hash_t<32>;
+using hash64_t = hash_t<64>;
+
+/* *************************************
+ * Bit Functions - Public
+ ***************************************/
+
+namespace bit_ops {
+/* ****************************************
+ * Intrinsics and Bit Operations
+ ******************************************/
+
+#if defined(_MSC_VER)
+inline uint32_t rotl32(uint32_t x, int32_t r)
+{
+ return _rotl(x, r);
+}
+inline uint64_t rotl64(uint64_t x, int32_t r)
+{
+ return _rotl64(x, r);
+}
+#else
+inline uint32_t rotl32(uint32_t x, int32_t r)
+{
+ return ((x << r) | (x >> (32 - r)));
+}
+inline uint64_t rotl64(uint64_t x, int32_t r)
+{
+ return ((x << r) | (x >> (64 - r)));
+}
+#endif
+
+#if defined(_MSC_VER) /* Visual Studio */
+inline uint32_t swap32(uint32_t x)
+{
+ return _byteswap_ulong(x);
+}
+inline uint64_t swap64(uint64_t x)
+{
+ return _byteswap_uint64(x);
+}
+#elif XXH_GCC_VERSION >= 403
+inline uint32_t swap32(uint32_t x)
+{
+ return __builtin_bswap32(x);
+}
+inline uint64_t swap64(uint64_t x)
+{
+ return __builtin_bswap64(x);
+}
+#else
+inline uint32_t swap32(uint32_t x)
+{
+ return ((x << 24) & 0xff000000) | ((x << 8) & 0x00ff0000) | ((x >> 8) & 0x0000ff00) | ((x >> 24) & 0x000000ff);
+}
+inline uint64_t swap64(uint64_t x)
+{
+ return ((x << 56) & 0xff00000000000000ULL) | ((x << 40) & 0x00ff000000000000ULL) |
+ ((x << 24) & 0x0000ff0000000000ULL) | ((x << 8) & 0x000000ff00000000ULL) | ((x >> 8) & 0x00000000ff000000ULL) |
+ ((x >> 24) & 0x0000000000ff0000ULL) | ((x >> 40) & 0x000000000000ff00ULL) |
+ ((x >> 56) & 0x00000000000000ffULL);
+}
+#endif
+template <size_t N> inline hash_t<N> rotl(hash_t<N> n, int32_t r){};
+
+template <> inline hash_t<32> rotl<32>(hash_t<32> n, int32_t r)
+{
+ return rotl32(n, r);
+};
+
+template <> inline hash_t<64> rotl<64>(hash_t<64> n, int32_t r)
+{
+ return rotl64(n, r);
+};
+
+template <size_t N> inline hash_t<N> swap(hash_t<N> n){};
+
+template <> inline hash_t<32> swap<32>(hash_t<32> n)
+{
+ return swap32(n);
+};
+
+template <> inline hash_t<64> swap<64>(hash_t<64> n)
+{
+ return swap64(n);
+};
+} // namespace bit_ops
+
+/* *************************************
+ * Memory Functions - Public
+ ***************************************/
+
+enum class alignment : uint8_t { aligned, unaligned };
+enum class endianness : uint8_t { big_endian = 0, little_endian = 1, unspecified = 2 };
+
+namespace mem_ops {
+/* *************************************
+ * Memory Access
+ ***************************************/
+#if (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS == 2))
+
+/* Force direct memory access. Only works on CPU which support unaligned memory access in hardware */
+template <size_t N> inline hash_t<N> read_unaligned(const void* memPtr)
+{
+ return *(const hash_t<N>*)memPtr;
+}
+
+#elif (defined(XXH_FORCE_MEMORY_ACCESS) && (XXH_FORCE_MEMORY_ACCESS == 1))
+
+/* __pack instructions are safer, but compiler specific, hence potentially problematic for some compilers */
+/* currently only defined for gcc and icc */
+template <size_t N> using unalign = union {
+ hash_t<N> uval;
+} __attribute((packed));
+
+template <size_t N> inline hash_t<N> read_unaligned(const void* memPtr)
+{
+ return ((const unalign*)memPtr)->uval;
+}
+#else
+
+/* portable and safe solution. Generally efficient.
+ * see : http://stackoverflow.com/a/32095106/646947
+ */
+template <size_t N> inline hash_t<N> read_unaligned(const void* memPtr)
+{
+ hash_t<N> val;
+ memcpy(&val, memPtr, sizeof(val));
+ return val;
+}
+
+#endif /* XXH_FORCE_DIRECT_MEMORY_ACCESS */
+
+inline hash_t<32> read32(const void* memPtr)
+{
+ return read_unaligned<32>(memPtr);
+}
+inline hash_t<64> read64(const void* memPtr)
+{
+ return read_unaligned<64>(memPtr);
+}
+
+/* *************************************
+ * Architecture Macros
+ ***************************************/
+
+/* XXH_CPU_LITTLE_ENDIAN can be defined externally, for example on the compiler command line */
+
+#ifndef XXH_CPU_LITTLE_ENDIAN
+
+inline endianness get_endian(endianness endian)
+{
+ static struct _dummy_t {
+ std::array<endianness, 3> endian_lookup = {endianness::big_endian, endianness::little_endian,
+ endianness::unspecified};
+ const int g_one = 1;
+ _dummy_t() { endian_lookup[2] = static_cast<endianness>(*(const char*)(&g_one)); }
+ } _dummy;
+
+ return _dummy.endian_lookup[(uint8_t)endian];
+}
+
+inline bool is_little_endian()
+{
+ return get_endian(endianness::unspecified) == endianness::little_endian;
+}
+
+#else
+constexpr endianness get_endian(endianness endian)
+{
+ constexpr std::array<endianness, 3> endian_lookup = {
+ {endianness::big_endian, endianness::little_endian,
+ (XXH_CPU_LITTLE_ENDIAN) ? endianness::little_endian : endianness::big_endian}};
+ return endian_lookup[static_cast<uint8_t>(endian)];
+}
+
+constexpr bool is_little_endian()
+{
+ return get_endian(endianness::unspecified) == endianness::little_endian;
+}
+
+#endif
+
+/* ***************************
+ * Memory reads
+ *****************************/
+
+template <size_t N> inline hash_t<N> readLE_align(const void* ptr, endianness endian, alignment align)
+{
+ if (align == alignment::unaligned) {
+ return endian == endianness::little_endian ? read_unaligned<N>(ptr) : bit_ops::swap<N>(read_unaligned<N>(ptr));
+ } else {
+ return endian == endianness::little_endian ? *reinterpret_cast<const hash_t<N>*>(ptr)
+ : bit_ops::swap<N>(*reinterpret_cast<const hash_t<N>*>(ptr));
+ }
+}
+
+template <size_t N> inline hash_t<N> readLE(const void* ptr, endianness endian)
+{
+ return readLE_align<N>(ptr, endian, alignment::unaligned);
+}
+
+template <size_t N> inline hash_t<N> readBE(const void* ptr)
+{
+ return is_little_endian() ? bit_ops::swap<N>(read_unaligned<N>(ptr)) : read_unaligned<N>(ptr);
+}
+
+template <size_t N> inline alignment get_alignment(const void* input)
+{
+ return ((XXH_FORCE_ALIGN_CHECK) && ((reinterpret_cast<uintptr_t>(input) & ((N / 8) - 1)) == 0))
+ ? xxh::alignment::aligned
+ : xxh::alignment::unaligned;
+}
+} // namespace mem_ops
+
+/* *******************************************************************
+ * Hash functions
+ *********************************************************************/
+
+namespace detail {
+/* *******************************************************************
+ * Hash functions - Implementation
+ *********************************************************************/
+
+constexpr static std::array<hash32_t, 5> primes32 = {{2654435761U, 2246822519U, 3266489917U, 668265263U, 374761393U}};
+constexpr static std::array<hash64_t, 5> primes64 = {{11400714785074694791ULL, 14029467366897019727ULL,
+ 1609587929392839161ULL, 9650029242287828579ULL,
+ 2870177450012600261ULL}};
+
+template <size_t N> constexpr hash_t<N> PRIME(int32_t n){};
+
+template <> constexpr hash32_t PRIME<32>(int32_t n)
+{
+ return primes32[n - 1];
+}
+
+template <> constexpr hash64_t PRIME<64>(int32_t n)
+{
+ return primes64[n - 1];
+}
+
+template <size_t N> inline hash_t<N> round(hash_t<N> seed, hash_t<N> input)
+{
+ seed += input * PRIME<N>(2);
+ seed = bit_ops::rotl<N>(seed, ((N == 32) ? 13 : 31));
+ seed *= PRIME<N>(1);
+ return seed;
+}
+
+inline hash64_t mergeRound64(hash64_t acc, hash64_t val)
+{
+ val = round<64>(0, val);
+ acc ^= val;
+ acc = acc * PRIME<64>(1) + PRIME<64>(4);
+ return acc;
+}
+
+template <size_t N>
+inline void endian_align_sub_mergeround(
+#if __cplusplus < 201703L
+ __attribute__((unused))
+#else
+ [[maybe_unused]]
+#endif
+ hash_t<N>& hash_ret,
+ hash_t<N> v1, hash_t<N> v2, hash_t<N> v3, hash_t<N> v4){};
+
+template <>
+inline void endian_align_sub_mergeround<64>(hash_t<64>& hash_ret, hash_t<64> v1, hash_t<64> v2, hash_t<64> v3,
+ hash_t<64> v4)
+{
+ hash_ret = mergeRound64(hash_ret, v1);
+ hash_ret = mergeRound64(hash_ret, v2);
+ hash_ret = mergeRound64(hash_ret, v3);
+ hash_ret = mergeRound64(hash_ret, v4);
+}
+
+template <size_t N>
+inline hash_t<N> endian_align_sub_ending(hash_t<N> hash_ret, const uint8_t* p, const uint8_t* bEnd,
+ xxh::endianness endian, xxh::alignment align){};
+
+template <>
+inline hash_t<32> endian_align_sub_ending<32>(hash_t<32> hash_ret, const uint8_t* p, const uint8_t* bEnd,
+ xxh::endianness endian, xxh::alignment align)
+{
+ while ((p + 4) <= bEnd) {
+ hash_ret += mem_ops::readLE_align<32>(p, endian, align) * PRIME<32>(3);
+ hash_ret = bit_ops::rotl<32>(hash_ret, 17) * PRIME<32>(4);
+ p += 4;
+ }
+
+ while (p < bEnd) {
+ hash_ret += (*p) * PRIME<32>(5);
+ hash_ret = bit_ops::rotl<32>(hash_ret, 11) * PRIME<32>(1);
+ p++;
+ }
+
+ hash_ret ^= hash_ret >> 15;
+ hash_ret *= PRIME<32>(2);
+ hash_ret ^= hash_ret >> 13;
+ hash_ret *= PRIME<32>(3);
+ hash_ret ^= hash_ret >> 16;
+
+ return hash_ret;
+}
+
+template <>
+inline hash_t<64> endian_align_sub_ending<64>(hash_t<64> hash_ret, const uint8_t* p, const uint8_t* bEnd,
+ xxh::endianness endian, xxh::alignment align)
+{
+ while (p + 8 <= bEnd) {
+ const hash64_t k1 = round<64>(0, mem_ops::readLE_align<64>(p, endian, align));
+ hash_ret ^= k1;
+ hash_ret = bit_ops::rotl<64>(hash_ret, 27) * PRIME<64>(1) + PRIME<64>(4);
+ p += 8;
+ }
+
+ if (p + 4 <= bEnd) {
+ hash_ret ^= static_cast<hash64_t>(mem_ops::readLE_align<32>(p, endian, align)) * PRIME<64>(1);
+ hash_ret = bit_ops::rotl<64>(hash_ret, 23) * PRIME<64>(2) + PRIME<64>(3);
+ p += 4;
+ }
+
+ while (p < bEnd) {
+ hash_ret ^= (*p) * PRIME<64>(5);
+ hash_ret = bit_ops::rotl<64>(hash_ret, 11) * PRIME<64>(1);
+ p++;
+ }
+
+ hash_ret ^= hash_ret >> 33;
+ hash_ret *= PRIME<64>(2);
+ hash_ret ^= hash_ret >> 29;
+ hash_ret *= PRIME<64>(3);
+ hash_ret ^= hash_ret >> 32;
+
+ return hash_ret;
+}
+
+template <size_t N>
+inline hash_t<N> endian_align(const void* input, size_t len, hash_t<N> seed, xxh::endianness endian,
+ xxh::alignment align)
+{
+ static_assert(!(N != 32 && N != 64), "You can only call endian_align in 32 or 64 bit mode.");
+
+ const uint8_t* p = static_cast<const uint8_t*>(input);
+ const uint8_t* bEnd = p + len;
+ hash_t<N> hash_ret;
+
+ if (len >= (N / 2)) {
+ const uint8_t* const limit = bEnd - (N / 2);
+ hash_t<N> v1 = seed + PRIME<N>(1) + PRIME<N>(2);
+ hash_t<N> v2 = seed + PRIME<N>(2);
+ hash_t<N> v3 = seed + 0;
+ hash_t<N> v4 = seed - PRIME<N>(1);
+
+ do {
+ v1 = round<N>(v1, mem_ops::readLE_align<N>(p, endian, align));
+ p += (N / 8);
+ v2 = round<N>(v2, mem_ops::readLE_align<N>(p, endian, align));
+ p += (N / 8);
+ v3 = round<N>(v3, mem_ops::readLE_align<N>(p, endian, align));
+ p += (N / 8);
+ v4 = round<N>(v4, mem_ops::readLE_align<N>(p, endian, align));
+ p += (N / 8);
+ } while (p <= limit);
+
+ hash_ret = bit_ops::rotl<N>(v1, 1) + bit_ops::rotl<N>(v2, 7) + bit_ops::rotl<N>(v3, 12) + bit_ops::rotl<N>(v4, 18);
+
+ endian_align_sub_mergeround<N>(hash_ret, v1, v2, v3, v4);
+ } else {
+ hash_ret = seed + PRIME<N>(5);
+ }
+
+ hash_ret += static_cast<hash_t<N>>(len);
+
+ return endian_align_sub_ending<N>(hash_ret, p, bEnd, endian, align);
+}
+} // namespace detail
+
+template <size_t N>
+hash_t<N> xxhash(const void* input, size_t len, hash_t<N> seed = 0, endianness endian = endianness::unspecified)
+{
+ static_assert(!(N != 32 && N != 64), "You can only call xxhash in 32 or 64 bit mode.");
+ return detail::endian_align<N>(input, len, seed, mem_ops::get_endian(endian), mem_ops::get_alignment<N>(input));
+}
+
+template <size_t N, typename T>
+hash_t<N> xxhash(const std::basic_string<T>& input, hash_t<N> seed = 0, endianness endian = endianness::unspecified)
+{
+ static_assert(!(N != 32 && N != 64), "You can only call xxhash in 32 or 64 bit mode.");
+ return detail::endian_align<N>(static_cast<const void*>(input.data()), input.length() * sizeof(T), seed,
+ mem_ops::get_endian(endian),
+ mem_ops::get_alignment<N>(static_cast<const void*>(input.data())));
+}
+
+template <size_t N, typename ContiguousIterator>
+hash_t<N> xxhash(ContiguousIterator begin, ContiguousIterator end, hash_t<N> seed = 0,
+ endianness endian = endianness::unspecified)
+{
+ static_assert(!(N != 32 && N != 64), "You can only call xxhash in 32 or 64 bit mode.");
+ using T = typename std::decay_t<decltype(*end)>;
+ return detail::endian_align<N>(static_cast<const void*>(&*begin), (end - begin) * sizeof(T), seed,
+ mem_ops::get_endian(endian),
+ mem_ops::get_alignment<N>(static_cast<const void*>(&*begin)));
+}
+
+template <size_t N, typename T>
+hash_t<N> xxhash(const std::vector<T>& input, hash_t<N> seed = 0, endianness endian = endianness::unspecified)
+{
+ static_assert(!(N != 32 && N != 64), "You can only call xxhash in 32 or 64 bit mode.");
+ return detail::endian_align<N>(static_cast<const void*>(input.data()), input.size() * sizeof(T), seed,
+ mem_ops::get_endian(endian),
+ mem_ops::get_alignment<N>(static_cast<const void*>(input.data())));
+}
+
+template <size_t N, typename T, size_t AN>
+hash_t<N> xxhash(const std::array<T, AN>& input, hash_t<N> seed = 0, endianness endian = endianness::unspecified)
+{
+ static_assert(!(N != 32 && N != 64), "You can only call xxhash in 32 or 64 bit mode.");
+ return detail::endian_align<N>(static_cast<const void*>(input.data()), AN * sizeof(T), seed,
+ mem_ops::get_endian(endian),
+ mem_ops::get_alignment<N>(static_cast<const void*>(input.data())));
+}
+
+template <size_t N, typename T>
+hash_t<N> xxhash(const std::initializer_list<T>& input, hash_t<N> seed = 0, endianness endian = endianness::unspecified)
+{
+ static_assert(!(N != 32 && N != 64), "You can only call xxhash in 32 or 64 bit mode.");
+ return detail::endian_align<N>(static_cast<const void*>(input.begin()), input.size() * sizeof(T), seed,
+ mem_ops::get_endian(endian),
+ mem_ops::get_alignment<N>(static_cast<const void*>(input.begin())));
+}
+
+/* *******************************************************************
+ * Hash streaming
+ *********************************************************************/
+enum class error_code : uint8_t { ok = 0, error };
+
+template <size_t N> class hash_state_t {
+ uint64_t total_len = 0;
+ hash_t<N> v1 = 0, v2 = 0, v3 = 0, v4 = 0;
+ std::array<hash_t<N>, 4> mem = {{0, 0, 0, 0}};
+ uint32_t memsize = 0;
+
+ inline error_code _update_impl(const void* input, size_t length, endianness endian)
+ {
+ const uint8_t* p = reinterpret_cast<const uint8_t*>(input);
+ const uint8_t* const bEnd = p + length;
+
+ if (!input) {
+ return xxh::error_code::error;
+ }
+
+ total_len += length;
+
+ if (memsize + length < (N / 2)) { /* fill in tmp buffer */
+ memcpy(reinterpret_cast<uint8_t*>(mem.data()) + memsize, input, length);
+ memsize += static_cast<uint32_t>(length);
+ return error_code::ok;
+ }
+
+ if (memsize) { /* some data left from previous update */
+ memcpy(reinterpret_cast<uint8_t*>(mem.data()) + memsize, input, (N / 2) - memsize);
+
+ const hash_t<N>* ptr = mem.data();
+ v1 = detail::round<N>(v1, mem_ops::readLE<N>(ptr, endian));
+ ptr++;
+ v2 = detail::round<N>(v2, mem_ops::readLE<N>(ptr, endian));
+ ptr++;
+ v3 = detail::round<N>(v3, mem_ops::readLE<N>(ptr, endian));
+ ptr++;
+ v4 = detail::round<N>(v4, mem_ops::readLE<N>(ptr, endian));
+
+ p += (N / 2) - memsize;
+ memsize = 0;
+ }
+
+ if (p <= bEnd - (N / 2)) {
+ const uint8_t* const limit = bEnd - (N / 2);
+
+ do {
+ v1 = detail::round<N>(v1, mem_ops::readLE<N>(p, endian));
+ p += (N / 8);
+ v2 = detail::round<N>(v2, mem_ops::readLE<N>(p, endian));
+ p += (N / 8);
+ v3 = detail::round<N>(v3, mem_ops::readLE<N>(p, endian));
+ p += (N / 8);
+ v4 = detail::round<N>(v4, mem_ops::readLE<N>(p, endian));
+ p += (N / 8);
+ } while (p <= limit);
+ }
+
+ if (p < bEnd) {
+ memcpy(mem.data(), p, static_cast<size_t>(bEnd - p));
+ memsize = static_cast<uint32_t>(bEnd - p);
+ }
+
+ return error_code::ok;
+ }
+
+ inline hash_t<N> _digest_impl(endianness endian) const
+ {
+ const uint8_t* p = reinterpret_cast<const uint8_t*>(mem.data());
+ const uint8_t* const bEnd = reinterpret_cast<const uint8_t*>(mem.data()) + memsize;
+ hash_t<N> hash_ret;
+
+ if (total_len > (N / 2)) {
+ hash_ret =
+ bit_ops::rotl<N>(v1, 1) + bit_ops::rotl<N>(v2, 7) + bit_ops::rotl<N>(v3, 12) + bit_ops::rotl<N>(v4, 18);
+
+ detail::endian_align_sub_mergeround<N>(hash_ret, v1, v2, v3, v4);
+ } else {
+ hash_ret = v3 + detail::PRIME<N>(5);
+ }
+
+ hash_ret += static_cast<hash_t<N>>(total_len);
+
+ return detail::endian_align_sub_ending<N>(hash_ret, p, bEnd, endian, alignment::unaligned);
+ }
+
+public:
+ hash_state_t(hash_t<N> seed = 0)
+ {
+ static_assert(!(N != 32 && N != 64), "You can only stream hashing in 32 or 64 bit mode.");
+ v1 = seed + detail::PRIME<N>(1) + detail::PRIME<N>(2);
+ v2 = seed + detail::PRIME<N>(2);
+ v3 = seed + 0;
+ v4 = seed - detail::PRIME<N>(1);
+ };
+
+ hash_state_t operator=(hash_state_t<N>& other) { memcpy(this, other, sizeof(hash_state_t<N>)); }
+
+ error_code reset(hash_t<N> seed = 0)
+ {
+ memset(this, 0, sizeof(hash_state_t<N>));
+ v1 = seed + detail::PRIME<N>(1) + detail::PRIME<N>(2);
+ v2 = seed + detail::PRIME<N>(2);
+ v3 = seed + 0;
+ v4 = seed - detail::PRIME<N>(1);
+ return error_code::ok;
+ }
+
+ error_code update(const void* input, size_t length, endianness endian = endianness::unspecified)
+ {
+ return _update_impl(input, length, mem_ops::get_endian(endian));
+ }
+
+ template <typename T>
+ error_code update(const std::basic_string<T>& input, endianness endian = endianness::unspecified)
+ {
+ return _update_impl(static_cast<const void*>(input.data()), input.length() * sizeof(T),
+ mem_ops::get_endian(endian));
+ }
+
+ template <typename ContiguousIterator>
+ error_code update(ContiguousIterator begin, ContiguousIterator end, endianness endian = endianness::unspecified)
+ {
+ using T = typename std::decay_t<decltype(*end)>;
+ return _update_impl(static_cast<const void*>(&*begin), (end - begin) * sizeof(T), mem_ops::get_endian(endian));
+ }
+
+ template <typename T> error_code update(const std::vector<T>& input, endianness endian = endianness::unspecified)
+ {
+ return _update_impl(static_cast<const void*>(input.data()), input.size() * sizeof(T), mem_ops::get_endian(endian));
+ }
+
+ template <typename T, size_t AN>
+ error_code update(const std::array<T, AN>& input, endianness endian = endianness::unspecified)
+ {
+ return _update_impl(static_cast<const void*>(input.data()), AN * sizeof(T), mem_ops::get_endian(endian));
+ }
+
+ template <typename T>
+ error_code update(const std::initializer_list<T>& input, endianness endian = endianness::unspecified)
+ {
+ return _update_impl(static_cast<const void*>(input.begin()), input.size() * sizeof(T), mem_ops::get_endian(endian));
+ }
+
+ hash_t<N> digest(endianness endian = endianness::unspecified) { return _digest_impl(mem_ops::get_endian(endian)); }
+};
+
+using hash_state32_t = hash_state_t<32>;
+using hash_state64_t = hash_state_t<64>;
+
+/* *******************************************************************
+ * Canonical
+ *********************************************************************/
+
+template <size_t N> struct canonical_t {
+ std::array<uint8_t, N / 8> digest;
+
+ canonical_t(hash_t<N> hash)
+ {
+ if (mem_ops::is_little_endian()) {
+ hash = bit_ops::swap<N>(hash);
+ }
+ memcpy(digest.data(), &hash, sizeof(canonical_t<N>));
+ }
+
+ hash_t<N> get_hash() const { return mem_ops::readBE<N>(&digest); }
+};
+
+using canonical32_t = canonical_t<32>;
+using canonical64_t = canonical_t<64>;
+} // namespace xxh
