diff options
Diffstat (limited to 'lib/util.h')
-rw-r--r-- | lib/util.h | 258 |
1 files changed, 54 insertions, 204 deletions
@@ -4,13 +4,13 @@ #pragma once +#include "quotient_export.h" + #include <QtCore/QLatin1String> #include <QtCore/QHashFunctions> -#include <functional> #include <memory> #include <unordered_map> -#include <optional> #ifndef Q_DISABLE_MOVE // Q_DISABLE_MOVE was introduced in Q_VERSION_CHECK(5,13,0) @@ -50,198 +50,7 @@ struct HashQ { template <typename KeyT, typename ValT> using UnorderedMap = std::unordered_map<KeyT, ValT, HashQ<KeyT>>; -namespace _impl { - template <typename TT> - constexpr inline auto IsOmittableValue = false; - template <typename TT> - constexpr inline auto IsOmittable = IsOmittableValue<std::decay_t<TT>>; -} - -constexpr auto none = std::nullopt; - -/** `std::optional` with tweaks - * - * The tweaks are: - * - streamlined assignment (operator=)/emplace()ment of values that can be - * used to implicitly construct the underlying type, including - * direct-list-initialisation, e.g.: - * \code - * struct S { int a; char b; } - * Omittable<S> o; - * o = { 1, 'a' }; // std::optional would require o = S { 1, 'a' } - * \endcode - * - entirely deleted value(). The technical reason is that Xcode 10 doesn't - * have it; but besides that, value_or() or (after explicit checking) - * `operator*()`/`operator->()` are better alternatives within Quotient - * that doesn't practice throwing exceptions (as doesn't most of Qt). - * - disabled non-const lvalue operator*() and operator->(), as it's too easy - * to inadvertently cause a value change through them. - * - edit() to provide a safe and explicit lvalue accessor instead of those - * above. Requires the underlying type to be default-constructible. - * Allows chained initialisation of nested Omittables: - * \code - * struct Inner { int member = 10; Omittable<int> innermost; }; - * struct Outer { int anotherMember = 10; Omittable<Inner> inner; }; - * Omittable<Outer> o; // = { 10, std::nullopt }; - * o.edit().inner.edit().innermost.emplace(42); - * \endcode - * - merge() - a soft version of operator= that only overwrites its first - * operand with the second one if the second one is not empty. - */ -template <typename T> -class Omittable : public std::optional<T> { -public: - using base_type = std::optional<T>; - using value_type = std::decay_t<T>; - - using std::optional<T>::optional; - - // Overload emplace() and operator=() to allow passing braced-init-lists - // (the standard emplace() does direct-initialisation but - // not direct-list-initialisation). - using base_type::operator=; - Omittable& operator=(const value_type& v) - { - base_type::operator=(v); - return *this; - } - Omittable& operator=(value_type&& v) - { - base_type::operator=(v); - return *this; - } - using base_type::emplace; - T& emplace(const T& val) { return base_type::emplace(val); } - T& emplace(T&& val) { return base_type::emplace(std::move(val)); } - - // use value_or() or check (with operator! or has_value) before accessing - // with operator-> or operator* - // The technical reason is that Xcode 10 has incomplete std::optional - // that has no value(); but using value() may also mean that you rely - // on the optional throwing an exception (which is not assumed practice - // throughout Quotient) or that you spend unnecessary CPU cycles on - // an extraneous has_value() check. - value_type& value() = delete; - const value_type& value() const = delete; - value_type& edit() - { - return this->has_value() ? base_type::operator*() : this->emplace(); - } - - [[deprecated("Use '!o' or '!o.has_value()' instead of 'o.omitted()'")]] - bool omitted() const - { - return !this->has_value(); - } - - //! Merge the value from another Omittable - //! \return true if \p other is not omitted and the value of - //! the current Omittable was different (or omitted), - //! in other words, if the current Omittable has changed; - //! false otherwise - template <typename T1> - auto merge(const Omittable<T1>& other) - -> std::enable_if_t<std::is_convertible_v<T1, T>, bool> - { - if (!other || (this->has_value() && **this == *other)) - return false; - emplace(*other); - return true; - } - - // Hide non-const lvalue operator-> and operator* as these are - // a bit too surprising: value() & doesn't lazy-create an object; - // and it's too easy to inadvertently change the underlying value. - - const value_type* operator->() const& { return base_type::operator->(); } - value_type* operator->() && { return base_type::operator->(); } - const value_type& operator*() const& { return base_type::operator*(); } - value_type& operator*() && { return base_type::operator*(); } -}; -template <typename T> -Omittable(T&&) -> Omittable<T>; - -namespace _impl { - template <typename T> - constexpr inline auto IsOmittableValue<Omittable<T>> = true; -} - -template <typename T1, typename T2> -inline auto merge(Omittable<T1>& lhs, T2&& rhs) -{ - return lhs.merge(std::forward<T2>(rhs)); -} - -//! \brief Merge the value from an Omittable -//! This is an adaptation of Omittable::merge() to the case when the value -//! on the left hand side is not an Omittable. -//! \return true if \p rhs is not omitted and the \p lhs value was different, -//! in other words, if \p lhs has changed; -//! false otherwise -template <typename T1, typename T2> -inline auto merge(T1& lhs, const Omittable<T2>& rhs) - -> std::enable_if_t<!_impl::IsOmittable<T1> - && std::is_convertible_v<T2, T1>, bool> -{ - if (!rhs || lhs == *rhs) - return false; - lhs = *rhs; - return true; -} - -namespace _impl { - template <typename AlwaysVoid, typename> - struct fn_traits {}; -} - -/// Determine traits of an arbitrary function/lambda/functor -/*! - * Doesn't work with generic lambdas and function objects that have - * operator() overloaded. - * \sa - * https://stackoverflow.com/questions/7943525/is-it-possible-to-figure-out-the-parameter-type-and-return-type-of-a-lambda#7943765 - */ -template <typename T> -struct function_traits - : public _impl::fn_traits<void, std::remove_reference_t<T>> {}; - -// Specialisation for a function -template <typename ReturnT, typename... ArgTs> -struct function_traits<ReturnT(ArgTs...)> { - using return_type = ReturnT; - using arg_types = std::tuple<ArgTs...>; - // Doesn't (and there's no plan to make it) work for "classic" - // member functions (i.e. outside of functors). - // See also the comment for wrap_in_function() below - using function_type = std::function<ReturnT(ArgTs...)>; -}; - -namespace _impl { - // Specialisation for function objects with (non-overloaded) operator() - // (this includes non-generic lambdas) - template <typename T> - struct fn_traits<decltype(void(&T::operator())), T> - : public fn_traits<void, decltype(&T::operator())> {}; - - // Specialisation for a member function - template <typename ReturnT, typename ClassT, typename... ArgTs> - struct fn_traits<void, ReturnT (ClassT::*)(ArgTs...)> - : function_traits<ReturnT(ArgTs...)> {}; - - // Specialisation for a const member function - template <typename ReturnT, typename ClassT, typename... ArgTs> - struct fn_traits<void, ReturnT (ClassT::*)(ArgTs...) const> - : function_traits<ReturnT(ArgTs...)> {}; -} // namespace _impl - -template <typename FnT> -using fn_return_t = typename function_traits<FnT>::return_type; - -template <typename FnT, int ArgN = 0> -using fn_arg_t = - std::tuple_element_t<ArgN, typename function_traits<FnT>::arg_types>; - -inline constexpr auto operator"" _ls(const char* s, std::size_t size) +constexpr auto operator"" _ls(const char* s, std::size_t size) { return QLatin1String(s, int(size)); } @@ -295,27 +104,68 @@ inline std::pair<InputIt, ForwardIt> findFirstOf(InputIt first, InputIt last, return std::make_pair(last, sLast); } +//! \brief An owning implementation pointer +//! +//! This is basically std::unique_ptr<> to hold your pimpl's but without having +//! to define default constructors/operator=() out of line. +//! Thanks to https://oliora.github.io/2015/12/29/pimpl-and-rule-of-zero.html +//! for inspiration +template <typename ImplType> +using ImplPtr = std::unique_ptr<ImplType, void (*)(ImplType*)>; + +// Why this works (see also the link above): because this defers the moment +// of requiring sizeof of ImplType to the place where makeImpl is invoked +// (which is located, necessarily, in the .cpp file after ImplType definition). +// The stock unique_ptr deleter (std::default_delete) normally needs sizeof +// at the same spot - as long as you defer definition of the owning type +// constructors and operator='s to the .cpp file as well. Which means you +// have to explicitly declare and define them (even if with = default), +// formally breaking the rule of zero; informally, just adding boilerplate code. +// The custom deleter itself is instantiated at makeImpl invocation - there's +// no way earlier to even know how ImplType will be deleted and whether that +// will need sizeof(ImplType) earlier. In theory it's a tad slower because +// the deleter is called by the pointer; however, the difference will not +// be noticeable (if exist at all) for any class with non-trivial contents. + +//! \brief make_unique for ImplPtr +//! +//! Since std::make_unique is not compatible with ImplPtr, this should be used +//! in constructors of frontend classes to create implementation instances. +template <typename ImplType, typename DeleterType = void (*)(ImplType*), + typename... ArgTs> +inline ImplPtr<ImplType> makeImpl(ArgTs&&... args) +{ + return ImplPtr<ImplType> { new ImplType(std::forward<ArgTs>(args)...), + [](ImplType* impl) { delete impl; } }; +} + +template <typename ImplType> +const inline ImplPtr<ImplType> ZeroImpl() +{ + return { nullptr, [](ImplType*) { /* nullptr doesn't need deletion */ } }; +} + /** Convert what looks like a URL or a Matrix ID to an HTML hyperlink */ -void linkifyUrls(QString& htmlEscapedText); +QUOTIENT_API void linkifyUrls(QString& htmlEscapedText); /** Sanitize the text before showing in HTML * * This does toHtmlEscaped() and removes Unicode BiDi marks. */ -QString sanitized(const QString& plainText); +QUOTIENT_API QString sanitized(const QString& plainText); /** Pretty-print plain text into HTML * * This includes HTML escaping of <,>,",& and calling linkifyUrls() */ -QString prettyPrint(const QString& plainText); +QUOTIENT_API QString prettyPrint(const QString& plainText); /** Return a path to cache directory after making sure that it exists * * The returned path has a trailing slash, clients don't need to append it. * \param dir path to cache directory relative to the standard cache path */ -QString cacheLocation(const QString& dirName); +QUOTIENT_API QString cacheLocation(const QString& dirName); /** Hue color component of based of the hash of the string. * @@ -324,13 +174,13 @@ QString cacheLocation(const QString& dirName); * Naming and range are the same as QColor's hueF method: * https://doc.qt.io/qt-5/qcolor.html#integer-vs-floating-point-precision */ -qreal stringToHueF(const QString& s); +QUOTIENT_API qreal stringToHueF(const QString& s); /** Extract the serverpart from MXID */ -QString serverPart(const QString& mxId); +QUOTIENT_API QString serverPart(const QString& mxId); -QString versionString(); -int majorVersion(); -int minorVersion(); -int patchVersion(); +QUOTIENT_API QString versionString(); +QUOTIENT_API int majorVersion(); +QUOTIENT_API int minorVersion(); +QUOTIENT_API int patchVersion(); } // namespace Quotient |