| 1 | /* |
| 2 | * Copyright (c) 2022 Francis Deslauriers <francis.deslauriers@efficios.com> |
| 3 | * Copyright (c) 2023 Philippe Proulx <pproulx@efficios.com> |
| 4 | * |
| 5 | * SPDX-License-Identifier: MIT |
| 6 | */ |
| 7 | |
| 8 | #ifndef BABELTRACE_CPP_COMMON_BT2_BORROWED_OBJECT_ITERATOR_HPP |
| 9 | #define BABELTRACE_CPP_COMMON_BT2_BORROWED_OBJECT_ITERATOR_HPP |
| 10 | |
| 11 | #include <cstdint> |
| 12 | #include <type_traits> |
| 13 | #include <utility> |
| 14 | |
| 15 | #include "common/assert.h" |
| 16 | |
| 17 | #include "borrowed-object-proxy.hpp" |
| 18 | |
| 19 | namespace bt2 { |
| 20 | |
| 21 | /* |
| 22 | * An iterator class to iterate an instance of a borrowed object |
| 23 | * container of type `ContainerT`. |
| 24 | * |
| 25 | * `ContainerT` must implement: |
| 26 | * |
| 27 | * // Returns the number of contained borrowed objects. |
| 28 | * std::uint64_t length() const noexcept; |
| 29 | * |
| 30 | * // Returns the borrowed object at index `i`. |
| 31 | * SomeObject operator[](std::uint64_t i) const noexcept; |
| 32 | */ |
| 33 | template <typename ContainerT> |
| 34 | class BorrowedObjectIterator final |
| 35 | { |
| 36 | friend ContainerT; |
| 37 | |
| 38 | public: |
| 39 | using Object = typename std::remove_reference< |
| 40 | decltype(std::declval<ContainerT>()[std::declval<std::uint64_t>()])>::type; |
| 41 | |
| 42 | private: |
| 43 | explicit BorrowedObjectIterator(const ContainerT container, const uint64_t idx) : |
| 44 | _mContainer {container}, _mIdx {idx} |
| 45 | { |
| 46 | } |
| 47 | |
| 48 | public: |
| 49 | BorrowedObjectIterator& operator++() noexcept |
| 50 | { |
| 51 | ++_mIdx; |
| 52 | return *this; |
| 53 | } |
| 54 | |
| 55 | BorrowedObjectIterator operator++(int) noexcept |
| 56 | { |
| 57 | const auto tmp = *this; |
| 58 | |
| 59 | ++(*this); |
| 60 | return tmp; |
| 61 | } |
| 62 | |
| 63 | bool operator==(const BorrowedObjectIterator& other) const noexcept |
| 64 | { |
| 65 | BT_ASSERT_DBG(_mContainer.isSame(other._mContainer)); |
| 66 | return _mIdx == other._mIdx; |
| 67 | } |
| 68 | |
| 69 | bool operator!=(const BorrowedObjectIterator& other) const noexcept |
| 70 | { |
| 71 | return !(*this == other); |
| 72 | } |
| 73 | |
| 74 | Object operator*() const noexcept |
| 75 | { |
| 76 | BT_ASSERT_DBG(_mIdx < _mContainer.length()); |
| 77 | return _mContainer[_mIdx]; |
| 78 | } |
| 79 | |
| 80 | BorrowedObjectProxy<Object> operator->() const noexcept |
| 81 | { |
| 82 | return BorrowedObjectProxy<Object> {(**this).libObjPtr()}; |
| 83 | } |
| 84 | |
| 85 | private: |
| 86 | ContainerT _mContainer; |
| 87 | std::uint64_t _mIdx; |
| 88 | }; |
| 89 | |
| 90 | } /* namespace bt2 */ |
| 91 | |
| 92 | #endif /* BABELTRACE_CPP_COMMON_BT2_BORROWED_OBJECT_ITERATOR_HPP */ |