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scylladb/db/sstables-format-selector.hh
2020-08-10 18:53:04 +03:00

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2.3 KiB
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/*
* Copyright (C) 2020 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 <seastar/core/semaphore.hh>
#include <seastar/core/future.hh>
#include <seastar/core/gate.hh>
#include <seastar/core/sharded.hh>
#include "sstables/version.hh"
#include "gms/feature.hh"
using namespace seastar;
class database;
namespace gms {
class gossiper;
class feature_service;
}
namespace db {
class sstables_format_selector;
class feature_enabled_listener : public gms::feature::listener {
sstables_format_selector& _selector;
sstables::sstable_version_types _format;
public:
feature_enabled_listener(sstables_format_selector& s, sstables::sstable_version_types format)
: _selector(s)
, _format(format)
{ }
void on_enabled() override;
};
class sstables_format_selector {
gms::gossiper& _gossiper;
sharded<gms::feature_service>& _features;
sharded<database>& _db;
seastar::named_semaphore _sem = {1, named_semaphore_exception_factory{"feature listeners"}};
seastar::gate _sel;
feature_enabled_listener _mc_feature_listener;
feature_enabled_listener _md_feature_listener;
sstables::sstable_version_types _selected_format = sstables::sstable_version_types::la;
future<> select_format(sstables::sstable_version_types new_format);
future<> read_sstables_format();
future<> do_maybe_select_format(sstables::sstable_version_types new_format);
public:
sstables_format_selector(gms::gossiper& g, sharded<gms::feature_service>& f, sharded<database>& db);
future<> start();
future<> stop();
future<> maybe_select_format(sstables::sstable_version_types new_format);
void sync() {
get_units(_sem, 1).get0();
}
};
} // namespace sstables