cursor.hpp

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// Copyright 2009-present MongoDB, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
 
#pragma once
 
#include <mongocxx/cursor-fwd.hpp> // IWYU pragma: export
 
//
 
#include <mongocxx/v1/cursor.hpp> // IWYU pragma: export
 
#include <cstddef>
#include <iterator>
#include <memory> // IWYU pragma: keep: backward compatibility, to be removed.
#include <utility>
 
#include <mongocxx/client-fwd.hpp>            // IWYU pragma: keep: backward compatibility, to be removed.
#include <mongocxx/client_encryption-fwd.hpp> // IWYU pragma: keep: backward compatibility, to be removed.
#include <mongocxx/collection-fwd.hpp>        // IWYU pragma: keep: backward compatibility, to be removed.
#include <mongocxx/database-fwd.hpp>          // IWYU pragma: keep: backward compatibility, to be removed.
#include <mongocxx/index_view-fwd.hpp>        // IWYU pragma: keep: backward compatibility, to be removed.
#include <mongocxx/search_index_view-fwd.hpp> // IWYU pragma: keep: backward compatibility, to be removed.
 
#include <bsoncxx/document/view.hpp>
#include <bsoncxx/stdx/optional.hpp> // IWYU pragma: keep: backward compatibility, to be removed.
 
#include <mongocxx/config/prelude.hpp>
 
namespace mongocxx {
namespace v_noabi {

class cursor {
   private:
    v1::cursor _cursor;
    bsoncxx::v_noabi::document::view _doc;
 
   public:
    using type = v1::cursor::type;
 
    class iterator;

    MONGOCXX_ABI_EXPORT_CDECL() cursor(cursor&& other) noexcept;

    MONGOCXX_ABI_EXPORT_CDECL(cursor&) operator=(cursor&& other) noexcept;

    MONGOCXX_ABI_EXPORT_CDECL() ~cursor();

    cursor(cursor const& other) = delete;
    cursor& operator=(cursor const& other) = delete;

    /* explicit(false) */ cursor(v1::cursor cursor) : _cursor{std::move(cursor)} {}

    explicit operator v1::cursor() && {
        return std::move(_cursor);
    }

    explicit operator v1::cursor() const& = delete;

    MONGOCXX_ABI_EXPORT_CDECL(iterator) begin();

    MONGOCXX_ABI_EXPORT_CDECL(iterator) end();
 
    class internal;
};

class cursor::iterator {
   public:
    using value_type = bsoncxx::v_noabi::document::view;
    using reference = bsoncxx::v_noabi::document::view&;
    using pointer = bsoncxx::v_noabi::document::view*;
    using iterator_category = std::input_iterator_tag;
    using difference_type = std::ptrdiff_t;

    MONGOCXX_ABI_EXPORT_CDECL(bsoncxx::v_noabi::document::view const&) operator*() const;

    MONGOCXX_ABI_EXPORT_CDECL(bsoncxx::v_noabi::document::view const*) operator->() const;

    MONGOCXX_ABI_EXPORT_CDECL(iterator&) operator++();

    void operator++(int) {
        this->operator++();
    }

    friend MONGOCXX_ABI_EXPORT_CDECL(bool) operator==(iterator const&, iterator const&);
 
    friend bool operator!=(cursor::iterator const& lhs, cursor::iterator const& rhs) noexcept {
        return !(lhs == rhs);
    }

 
   private:
    friend cursor;
 
    explicit iterator(cursor* cursor);
 
    bool is_exhausted() const;
 
    // If this pointer is null, the iterator is considered "past-the-end".
    cursor* _cursor;
};
 
} // namespace v_noabi
} // namespace mongocxx
 
namespace mongocxx {
namespace v_noabi {

inline v_noabi::cursor from_v1(v1::cursor v) {
    return {std::move(v)};
}

inline v1::cursor to_v1(v_noabi::cursor v) {
    return v1::cursor{std::move(v)};
}
 
} // namespace v_noabi
} // namespace mongocxx
 
#include <mongocxx/config/postlude.hpp>