Files
scylladb/digester.hh
Rafael Ávila de Espíndola fd5ea2df5a Avoid including cryptopp headers
cryptopp's config.h has the following pragma:

 #pragma GCC diagnostic ignored "-Wunused-function"

It is not wrapped in a push/pop. Because of that, including cryptopp
headers disables that warning on scylla code too.

The issue has been reported as
https://github.com/weidai11/cryptopp/issues/793

To work around it, this patch uses a pimpl to have a single .cc file
that has to include cryptopp headers.

While at it, it also reduces the differences and code duplication
between the md5 and sha1 hashers.

Signed-off-by: Rafael Ávila de Espíndola <espindola@scylladb.com>
2019-02-20 08:03:46 -08:00

78 lines
2.1 KiB
C++

/*
* Copyright (C) 2018 ScyllaDB
*/
/*
* This file is part of Scylla.
*
* Scylla is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* Scylla is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with Scylla. If not, see <http://www.gnu.org/licenses/>.
*/
#pragma once
#include "digest_algorithm.hh"
#include "hashers.hh"
#include "xx_hasher.hh"
#include <type_traits>
#include <variant>
namespace query {
struct noop_hasher {
void update(const char* ptr, size_t length) { }
std::array<uint8_t, 16> finalize_array() { return std::array<uint8_t, 16>(); };
};
class digester final {
std::variant<noop_hasher, md5_hasher, xx_hasher> _impl;
public:
explicit digester(digest_algorithm algo) {
switch (algo) {
case digest_algorithm::MD5:
_impl = md5_hasher();
break;
case digest_algorithm::xxHash:
_impl = xx_hasher();
break;
case digest_algorithm ::none:
_impl = noop_hasher();
break;
}
}
template<typename T, typename... Args>
void feed_hash(const T& value, Args&&... args) {
std::visit([&] (auto& hasher) {
::feed_hash(hasher, value, std::forward<Args>(args)...);
}, _impl);
};
std::array<uint8_t, 16> finalize_array() {
return std::visit([&] (auto& hasher) {
return hasher.finalize_array();
}, _impl);
}
};
using default_hasher = xx_hasher;
template<typename Hasher>
using using_hash_of_hash = std::negation<std::disjunction<std::is_same<Hasher, md5_hasher>, std::is_same<Hasher, noop_hasher>>>;
template<typename Hasher>
inline constexpr bool using_hash_of_hash_v = using_hash_of_hash<Hasher>::value;
}