From 3bf42c6ff3805a0d42bbc661794a95ff31bedc26 Mon Sep 17 00:00:00 2001 From: untodesu Date: Sat, 15 Mar 2025 16:22:09 +0500 Subject: Add whatever I was working on for the last month --- deps/include/entt/resource/resource.hpp | 259 ++++++++++++++++++++++++++++++++ 1 file changed, 259 insertions(+) create mode 100644 deps/include/entt/resource/resource.hpp (limited to 'deps/include/entt/resource/resource.hpp') diff --git a/deps/include/entt/resource/resource.hpp b/deps/include/entt/resource/resource.hpp new file mode 100644 index 0000000..8d73ace --- /dev/null +++ b/deps/include/entt/resource/resource.hpp @@ -0,0 +1,259 @@ +#ifndef ENTT_RESOURCE_RESOURCE_HPP +#define ENTT_RESOURCE_RESOURCE_HPP + +#include +#include +#include +#include "fwd.hpp" + +namespace entt { + +/** + * @brief Basic resource handle. + * + * A handle wraps a resource and extends its lifetime. It also shares the same + * resource with all other handles constructed from the same element.
+ * As a rule of thumb, resources should never be copied nor moved. Handles are + * the way to go to push references around. + * + * @tparam Type Type of resource managed by a handle. + */ +template +class resource { + template + friend class resource; + + template + static constexpr bool is_acceptable_v = !std::is_same_v && std::is_constructible_v; + +public: + /*! @brief Resource type. */ + using element_type = Type; + /*! @brief Handle type. */ + using handle_type = std::shared_ptr; + + /*! @brief Default constructor. */ + resource() noexcept + : value{} {} + + /** + * @brief Creates a new resource handle. + * @param res A handle to a resource. + */ + explicit resource(handle_type res) noexcept + : value{std::move(res)} {} + + /*! @brief Default copy constructor. */ + resource(const resource &) noexcept = default; + + /*! @brief Default move constructor. */ + resource(resource &&) noexcept = default; + + /** + * @brief Aliasing constructor. + * @tparam Other Type of resource managed by the received handle. + * @param other The handle with which to share ownership information. + * @param res Unrelated and unmanaged resources. + */ + template + resource(const resource &other, element_type &res) noexcept + : value{other.value, std::addressof(res)} {} + + /** + * @brief Copy constructs a handle which shares ownership of the resource. + * @tparam Other Type of resource managed by the received handle. + * @param other The handle to copy from. + */ + template>> + resource(const resource &other) noexcept + : value{other.value} {} + + /** + * @brief Move constructs a handle which takes ownership of the resource. + * @tparam Other Type of resource managed by the received handle. + * @param other The handle to move from. + */ + template>> + resource(resource &&other) noexcept + : value{std::move(other.value)} {} + + /*! @brief Default destructor. */ + ~resource() noexcept = default; + + /** + * @brief Default copy assignment operator. + * @return This resource handle. + */ + resource &operator=(const resource &) noexcept = default; + + /** + * @brief Default move assignment operator. + * @return This resource handle. + */ + resource &operator=(resource &&) noexcept = default; + + /** + * @brief Copy assignment operator from foreign handle. + * @tparam Other Type of resource managed by the received handle. + * @param other The handle to copy from. + * @return This resource handle. + */ + template>> + resource &operator=(const resource &other) noexcept { + value = other.value; + return *this; + } + + /** + * @brief Move assignment operator from foreign handle. + * @tparam Other Type of resource managed by the received handle. + * @param other The handle to move from. + * @return This resource handle. + */ + template>> + resource &operator=(resource &&other) noexcept { + value = std::move(other.value); + return *this; + } + + /** + * @brief Returns a reference to the managed resource. + * + * @warning + * The behavior is undefined if the handle doesn't contain a resource. + * + * @return A reference to the managed resource. + */ + [[nodiscard]] element_type &operator*() const noexcept { + return *value; + } + + /*! @copydoc operator* */ + [[nodiscard]] operator element_type &() const noexcept { + return *value; + } + + /** + * @brief Returns a pointer to the managed resource. + * @return A pointer to the managed resource. + */ + [[nodiscard]] element_type *operator->() const noexcept { + return value.get(); + } + + /** + * @brief Returns true if a handle contains a resource, false otherwise. + * @return True if the handle contains a resource, false otherwise. + */ + [[nodiscard]] explicit operator bool() const noexcept { + return static_cast(value); + } + + /*! @brief Releases the ownership of the managed resource. */ + void reset() { + value.reset(); + } + + /** + * @brief Replaces the managed resource. + * @param other A handle to a resource. + */ + void reset(handle_type other) { + value = std::move(other); + } + + /** + * @brief Returns the underlying resource handle. + * @return The underlying resource handle. + */ + [[nodiscard]] const handle_type &handle() const noexcept { + return value; + } + +private: + handle_type value; +}; + +/** + * @brief Compares two handles. + * @tparam Lhs Type of resource managed by the first handle. + * @tparam Rhs Type of resource managed by the second handle. + * @param lhs A valid handle. + * @param rhs A valid handle. + * @return True if both handles refer to the same resource, false otherwise. + */ +template +[[nodiscard]] bool operator==(const resource &lhs, const resource &rhs) noexcept { + return (std::addressof(*lhs) == std::addressof(*rhs)); +} + +/** + * @brief Compares two handles. + * @tparam Lhs Type of resource managed by the first handle. + * @tparam Rhs Type of resource managed by the second handle. + * @param lhs A valid handle. + * @param rhs A valid handle. + * @return False if both handles refer to the same resource, true otherwise. + */ +template +[[nodiscard]] bool operator!=(const resource &lhs, const resource &rhs) noexcept { + return !(lhs == rhs); +} + +/** + * @brief Compares two handles. + * @tparam Lhs Type of resource managed by the first handle. + * @tparam Rhs Type of resource managed by the second handle. + * @param lhs A valid handle. + * @param rhs A valid handle. + * @return True if the first handle is less than the second, false otherwise. + */ +template +[[nodiscard]] bool operator<(const resource &lhs, const resource &rhs) noexcept { + return (std::addressof(*lhs) < std::addressof(*rhs)); +} + +/** + * @brief Compares two handles. + * @tparam Lhs Type of resource managed by the first handle. + * @tparam Rhs Type of resource managed by the second handle. + * @param lhs A valid handle. + * @param rhs A valid handle. + * @return True if the first handle is greater than the second, false otherwise. + */ +template +[[nodiscard]] bool operator>(const resource &lhs, const resource &rhs) noexcept { + return rhs < lhs; +} + +/** + * @brief Compares two handles. + * @tparam Lhs Type of resource managed by the first handle. + * @tparam Rhs Type of resource managed by the second handle. + * @param lhs A valid handle. + * @param rhs A valid handle. + * @return True if the first handle is less than or equal to the second, false + * otherwise. + */ +template +[[nodiscard]] bool operator<=(const resource &lhs, const resource &rhs) noexcept { + return !(lhs > rhs); +} + +/** + * @brief Compares two handles. + * @tparam Lhs Type of resource managed by the first handle. + * @tparam Rhs Type of resource managed by the second handle. + * @param lhs A valid handle. + * @param rhs A valid handle. + * @return True if the first handle is greater than or equal to the second, + * false otherwise. + */ +template +[[nodiscard]] bool operator>=(const resource &lhs, const resource &rhs) noexcept { + return !(lhs < rhs); +} + +} // namespace entt + +#endif -- cgit