Files
scylladb/utils/xx_hasher.hh
Kefu Chai 7215d4bfe9 utils: do not include unused headers
these unused includes were identifier by clang-include-cleaner. after
auditing these source files, all of the reports have been confirmed.

please note, because quite a few source files relied on
`utils/to_string.hh` to pull in the specialization of
`fmt::formatter<std::optional<T>>`, after removing
`#include <fmt/std.h>` from `utils/to_string.hh`, we have to
include `fmt/std.h` directly.

Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
2025-01-14 07:56:39 -05:00

57 lines
1.2 KiB
C++

/*
* Copyright (C) 2018-present ScyllaDB
*/
/*
* SPDX-License-Identifier: LicenseRef-ScyllaDB-Source-Available-1.0
*/
#pragma once
#include "bytes_fwd.hh"
#include "utils/serialization.hh"
#pragma GCC diagnostic push
#pragma GCC diagnostic ignored "-Warray-bounds"
#include <xxhash.h>
#pragma GCC diagnostic pop
#include <array>
class xx_hasher {
static constexpr size_t digest_size = 16;
XXH64_state_t _state;
public:
explicit xx_hasher(uint64_t seed = 0) noexcept {
XXH64_reset(&_state, seed);
}
void update(const char* ptr, size_t length) noexcept {
XXH64_update(&_state, ptr, length);
}
bytes finalize() {
bytes digest{bytes::initialized_later(), digest_size};
serialize_to(digest.begin());
return digest;
}
std::array<uint8_t, digest_size> finalize_array() {
std::array<uint8_t, digest_size> digest;
serialize_to(digest.begin());
return digest;
}
uint64_t finalize_uint64() {
return XXH64_digest(&_state);
}
private:
template<typename OutIterator>
void serialize_to(OutIterator&& out) {
serialize_int64(out, 0);
serialize_int64(out, finalize_uint64());
}
};