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/**
* Copyright (C) 2016 MongoDB Inc.
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU Affero General Public License, version 3,
* as published by the Free Software Foundation.
*
* This program 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 Affero General Public License for more details.
*
* You should have received a copy of the GNU Affero General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* As a special exception, the copyright holders give permission to link the
* code of portions of this program with the OpenSSL library under certain
* conditions as described in each individual source file and distribute
* linked combinations including the program with the OpenSSL library. You
* must comply with the GNU Affero General Public License in all respects for
* all of the code used other than as permitted herein. If you modify file(s)
* with this exception, you may extend this exception to your version of the
* file(s), but you are not obligated to do so. If you do not wish to do so,
* delete this exception statement from your version. If you delete this
* exception statement from all source files in the program, then also delete
* it in the license file.
*/
#pragma once
#include <iostream>
#include <string>
#include "mongo/base/string_data.h"
#include "mongo/bson/util/builder.h"
namespace mongo {
class NamespaceString;
/**
* Representation of a shard identifier.
*/
class ShardId {
public:
friend std::ostream& operator<<(std::ostream&, const ShardId&);
ShardId() = default;
// Note that this c-tor allows the implicit conversion from std::string
ShardId(std::string shardId) : _shardId(std::move(shardId)) {}
// Implicit StringData conversion
operator StringData();
bool operator==(const ShardId&) const;
bool operator!=(const ShardId&) const;
bool operator==(const std::string&) const;
bool operator!=(const std::string&) const;
template <size_t N>
bool operator==(const char (&val)[N]) const {
return (strncmp(val, _shardId.data(), N) == 0);
}
template <size_t N>
bool operator!=(const char (&val)[N]) const {
return (strncmp(val, _shardId.data(), N) != 0);
}
// The operator< is needed to do proper comparison in a std::map
bool operator<(const ShardId&) const;
const std::string& toString() const;
/**
* Returns -1, 0, or 1 if 'this' is less, equal, or greater than 'other' in
* lexicographical order.
*/
int compare(const ShardId& other) const;
/**
* Returns true if _shardId is not empty. Subject to include more validations in the future.
*/
bool isValid() const;
/**
* Functor compatible with std::hash for std::unordered_{map,set}
*/
struct Hasher {
std::size_t operator()(const ShardId&) const;
};
private:
std::string _shardId;
};
template <typename Allocator>
StringBuilderImpl<Allocator>& operator<<(StringBuilderImpl<Allocator>& stream,
const ShardId& shardId) {
return stream << shardId.toString();
}
} // namespace mongo
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