view.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 <bsoncxx/document/view-fwd.hpp> // IWYU pragma: export
 
//
 
#include <bsoncxx/v1/document/view.hpp> // IWYU pragma: export
 
#include <cstddef>
#include <cstdint>
#include <cstring>
#include <iterator>
 
#include <bsoncxx/document/element.hpp>
#include <bsoncxx/stdx/string_view.hpp>
 
#include <bsoncxx/config/prelude.hpp>
 
namespace bsoncxx {
namespace v_noabi {
namespace document {

class view {
   private:
    v1::document::view _view;
    std::size_t _length;
 
   public:
    class const_iterator;

    using iterator = const_iterator;

    view() : _view{}, _length{_view.length()} {}

    /* explicit(false) */ view(v1::document::view const& v) : _view{v}, _length{v.length()} {}

    view(std::uint8_t const* data, std::size_t length) : _view{data}, _length{length} {}

    explicit operator v1::document::view() const {
        return _view;
    }

    BSONCXX_ABI_EXPORT_CDECL(const_iterator) cbegin() const;

    const_iterator cend() const;

    const_iterator begin() const;

    const_iterator end() const;

    BSONCXX_ABI_EXPORT_CDECL(const_iterator) find(v1::stdx::string_view key) const;

    v_noabi::document::element operator[](v1::stdx::string_view key) const;

    std::uint8_t const* data() const {
        return _view.data();
    }

    std::size_t size() const {
        return _length; // Do NOT use _view.size().
    }

    std::size_t length() const {
        return _length; // Do NOT use _view.length().
    }

    bool empty() const {
        return _length == 5u; // Do NOT use _view.empty().
    }

    friend bool operator==(view lhs, view rhs) {
        return (lhs._length == rhs._length) && (std::memcmp(lhs.data(), rhs.data(), lhs._length) == 0);
    }
 
    friend bool operator!=(view lhs, view rhs) {
        return !(lhs == rhs);
    }

};

class view::const_iterator {
   private:
    v_noabi::document::element _element;
 
   public:
    using value_type = element;
    using reference = element&;
    using pointer = element*;
    using iterator_category = std::forward_iterator_tag;
    using difference_type = std::ptrdiff_t;
 
    const_iterator() = default;
 
    explicit const_iterator(v_noabi::document::element const& element) : _element(element) {}
 
    reference operator*() {
        return _element;
    }
 
    pointer operator->() {
        return &_element;
    }
 
    BSONCXX_ABI_EXPORT_CDECL(const_iterator&) operator++();
 
    const_iterator operator++(int) {
        const_iterator before(*this);
        operator++();
        return before;
    }

    friend bool operator==(const_iterator const& lhs, const_iterator const& rhs) {
        return lhs._element.raw() == rhs._element.raw() && lhs._element.offset() == rhs._element.offset();
    }
 
    friend bool operator!=(const_iterator const& lhs, const_iterator const& rhs) {
        return !(lhs == rhs);
    }

};
 
inline v_noabi::document::element view::operator[](v1::stdx::string_view key) const {
    return *(this->find(key));
}
 
inline view::const_iterator view::cend() const {
    return {};
}
 
inline view::const_iterator view::begin() const {
    return this->cbegin();
}
 
inline view::const_iterator view::end() const {
    return this->cend();
}
 
} // namespace document
} // namespace v_noabi
} // namespace bsoncxx
 
namespace bsoncxx {
namespace v_noabi {

inline v_noabi::document::view from_v1(v1::document::view const& v) {
    return {v};
}

inline v1::document::view to_v1(v_noabi::document::view const& v) {
    return v1::document::view{v};
}
 
} // namespace v_noabi
} // namespace bsoncxx
 
#include <bsoncxx/config/postlude.hpp>