diff options
Diffstat (limited to 'src/promise.hpp')
| -rw-r--r-- | src/promise.hpp | 745 |
1 files changed, 0 insertions, 745 deletions
diff --git a/src/promise.hpp b/src/promise.hpp deleted file mode 100644 index 593d5c1..0000000 --- a/src/promise.hpp +++ /dev/null @@ -1,745 +0,0 @@ -#ifndef _CPPROMISE_HPP -#define _CPPROMISE_HPP - -/** - * MIT License - * Copyright (c) 2018 Ted Yin <[email protected]> - * - * Permission is hereby granted, free of charge, to any person obtaining a copy - * of this software and associated documentation files (the "Software"), to deal - * in the Software without restriction, including without limitation the rights - * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell - * copies of the Software, and to permit persons to whom the Software is - * furnished to do so, subject to the following conditions: - * - * The above copyright notice and this permission notice shall be included in all - * copies or substantial portions of the Software. - * - * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR - * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, - * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE - * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER - * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, - * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE - * SOFTWARE. - */ - -#include <stack> -#include <vector> -#include <memory> -#include <functional> -#include <type_traits> - -#if __cplusplus >= 201703L -#ifdef __has_include -# if __has_include(<any>) -# include <any> -# ifdef __cpp_lib_any -# define _CPPROMISE_STD_ANY -# endif -# endif -#endif -#endif - -#ifndef _CPPROMISE_STD_ANY -#include <boost/any.hpp> -#endif - -/** - * Implement type-safe Promise primitives similar to the ones specified by - * Javascript Promise/A+. - */ -namespace promise { -#ifdef _CPPROMISE_STD_ANY - using pm_any_t = std::any; - template<typename T> - constexpr auto any_cast = static_cast<T(*)(const std::any&)>(std::any_cast<T>); - using bad_any_cast = std::bad_any_cast; -#else -# warning "using boost::any" -# pragma message "using boost::any" - using pm_any_t = boost::any; - template<typename T> - constexpr auto any_cast = static_cast<T(*)(const boost::any&)>(boost::any_cast<T>); - using bad_any_cast = boost::bad_any_cast; -#endif - using callback_t = std::function<void()>; - using values_t = std::vector<pm_any_t>; - - /* match lambdas */ - template<typename T> - struct function_traits: - public function_traits<decltype(&T::operator())> {}; - - template<typename ReturnType> - struct function_traits<ReturnType()> { - using ret_type = ReturnType; - using arg_type = void; - using empty_arg = void; - }; - - /* match plain functions */ - template<typename ReturnType, typename ArgType> - struct function_traits<ReturnType(ArgType)> { - using ret_type = ReturnType; - using arg_type = ArgType; - using non_empty_arg = void; - }; - - /* match function pointers */ - template<typename ReturnType, typename... ArgType> - struct function_traits<ReturnType(*)(ArgType...)>: - public function_traits<ReturnType(ArgType...)> {}; - - /* match const member functions */ - template<typename ClassType, typename ReturnType, typename... ArgType> - struct function_traits<ReturnType(ClassType::*)(ArgType...) const>: - public function_traits<ReturnType(ArgType...)> {}; - - /* match member functions */ - template<typename ClassType, typename ReturnType, typename... ArgType> - struct function_traits<ReturnType(ClassType::*)(ArgType...)>: - public function_traits<ReturnType(ArgType...)> {}; - - template<typename Func, typename ReturnType> - using enable_if_return = typename std::enable_if< - std::is_same<typename function_traits<Func>::ret_type, - ReturnType>::value>; - - template<typename Func, typename ReturnType> - using disable_if_return = typename std::enable_if< - !std::is_same<typename function_traits<Func>::ret_type, - ReturnType>::value>; - - template<typename Func, typename ArgType> - using enable_if_arg = typename std::enable_if< - std::is_same<typename function_traits<Func>::arg_type, - ArgType>::value>; - - template<typename Func, typename ArgType> - using disable_if_arg = typename std::enable_if< - !std::is_same<typename function_traits<Func>::arg_type, - ArgType>::value>; - - class Promise; - //class promise_t: public std::shared_ptr<Promise> { - class promise_t { - Promise *pm; - size_t *ref_cnt; - public: - friend Promise; - template<typename PList> friend promise_t all(const PList &promise_list); - template<typename PList> friend promise_t race(const PList &promise_list); - - inline promise_t(); - inline ~promise_t(); - template<typename Func> inline promise_t(Func callback); - - void swap(promise_t &other) { - std::swap(pm, other.pm); - std::swap(ref_cnt, other.ref_cnt); - } - - promise_t &operator=(const promise_t &other) { - if (this != &other) - { - promise_t tmp(other); - tmp.swap(*this); - } - return *this; - } - - promise_t &operator=(promise_t &&other) { - if (this != &other) - { - promise_t tmp(std::move(other)); - tmp.swap(*this); - } - return *this; - } - - promise_t(const promise_t &other): - pm(other.pm), - ref_cnt(other.ref_cnt) { - ++*ref_cnt; - } - - promise_t(promise_t &&other): - pm(other.pm), - ref_cnt(other.ref_cnt) { - other.pm = nullptr; - } - - Promise *operator->() const { - return pm; - } - - template<typename T> inline void resolve(T result) const; - template<typename T> inline void reject(T reason) const; - inline void resolve() const; - inline void reject() const; - - template<typename FuncFulfilled> - inline promise_t then(FuncFulfilled on_fulfilled) const; - - template<typename FuncFulfilled, typename FuncRejected> - inline promise_t then(FuncFulfilled on_fulfilled, - FuncRejected on_rejected) const; - - template<typename FuncRejected> - inline promise_t fail(FuncRejected on_rejected) const; - }; - -#define PROMISE_ERR_INVALID_STATE do {throw std::runtime_error("invalid promise state");} while (0) -#define PROMISE_ERR_MISMATCH_TYPE do {throw std::runtime_error("mismatching promise value types");} while (0) - - class Promise { - template<typename PList> friend promise_t all(const PList &promise_list); - template<typename PList> friend promise_t race(const PList &promise_list); - std::vector<callback_t> fulfilled_callbacks; - std::vector<callback_t> rejected_callbacks; -#ifdef CPPROMISE_USE_STACK_FREE - std::vector<Promise *> fulfilled_pms; - std::vector<Promise *> rejected_pms; -#endif - enum class State { - Pending, -#ifdef CPPROMISE_USE_STACK_FREE - PreFulfilled, - PreRejected, -#endif - Fulfilled, - Rejected, - } state; - pm_any_t result; - pm_any_t reason; - - void add_on_fulfilled(callback_t &&cb) { - fulfilled_callbacks.push_back(std::move(cb)); - } - - void add_on_rejected(callback_t &&cb) { - rejected_callbacks.push_back(std::move(cb)); - } - - template<typename Func, - typename function_traits<Func>::non_empty_arg * = nullptr> - static constexpr auto cps_transform( - Func f, const pm_any_t &result, const promise_t &npm) { - return [&result, npm, f = std::forward<Func>(f)]() mutable { -#ifndef CPPROMISE_USE_STACK_FREE - f(result)->then( - [npm] (pm_any_t result) {npm->resolve(result);}, - [npm] (pm_any_t reason) {npm->reject(reason);}); -#else - promise_t rpm{f(result)}; - rpm->then( - [rpm, npm] (pm_any_t result) { - npm->_resolve(result); - }, - [rpm, npm] (pm_any_t reason) { - npm->_reject(reason); - }); - rpm->_dep_resolve(npm); - rpm->_dep_reject(npm); -#endif - }; - } - - template<typename Func, - typename function_traits<Func>::empty_arg * = nullptr> - static constexpr auto cps_transform( - Func f, const pm_any_t &, const promise_t &npm) { - return [npm, f = std::forward<Func>(f)]() mutable { -#ifndef CPPROMISE_USE_STACK_FREE - f()->then( - [npm] (pm_any_t result) {npm->resolve(result);}, - [npm] (pm_any_t reason) {npm->reject(reason);}); -#else - promise_t rpm{f()}; - rpm->then( - [rpm, npm] (pm_any_t result) { - npm->_resolve(result); - }, - [rpm, npm] (pm_any_t reason) { - npm->_reject(reason); - }); - rpm->_dep_resolve(npm); - rpm->_dep_reject(npm); -#endif - }; - } - - template<typename Func, - typename enable_if_return<Func, promise_t>::type * = nullptr> - constexpr auto gen_on_fulfilled(Func on_fulfilled, const promise_t &npm) { - return cps_transform(std::forward<Func>(on_fulfilled), this->result, npm); - } - - template<typename Func, - typename enable_if_return<Func, promise_t>::type * = nullptr> - constexpr auto gen_on_rejected(Func on_rejected, const promise_t &npm) { - return cps_transform(std::forward<Func>(on_rejected), this->reason, npm); - } - - - template<typename Func, - typename enable_if_return<Func, void>::type * = nullptr, - typename function_traits<Func>::non_empty_arg * = nullptr> - constexpr auto gen_on_fulfilled(Func on_fulfilled, const promise_t &npm) { - return [this, npm, - on_fulfilled = std::forward<Func>(on_fulfilled)]() mutable { - on_fulfilled(result); - npm->_resolve(); - }; - } - - template<typename Func, - typename enable_if_return<Func, void>::type * = nullptr, - typename function_traits<Func>::empty_arg * = nullptr> - constexpr auto gen_on_fulfilled(Func on_fulfilled, const promise_t &npm) { - return [on_fulfilled = std::forward<Func>(on_fulfilled), npm]() mutable { - on_fulfilled(); - npm->_resolve(); - }; - } - - template<typename Func, - typename enable_if_return<Func, void>::type * = nullptr, - typename function_traits<Func>::non_empty_arg * = nullptr> - constexpr auto gen_on_rejected(Func on_rejected, const promise_t &npm) { - return [this, npm, - on_rejected = std::forward<Func>(on_rejected)]() mutable { - on_rejected(reason); - npm->_reject(); - }; - } - - template<typename Func, - typename enable_if_return<Func, void>::type * = nullptr, - typename function_traits<Func>::empty_arg * = nullptr> - constexpr auto gen_on_rejected(Func on_rejected, const promise_t &npm) { - return [npm, - on_rejected = std::forward<Func>(on_rejected)]() mutable { - on_rejected(); - npm->_reject(); - }; - } - - template<typename Func, - typename enable_if_return<Func, pm_any_t>::type * = nullptr, - typename function_traits<Func>::non_empty_arg * = nullptr> - constexpr auto gen_on_fulfilled(Func on_fulfilled, const promise_t &npm) { - return [this, npm, - on_fulfilled = std::forward<Func>(on_fulfilled)]() mutable { - npm->_resolve(on_fulfilled(result)); - }; - } - - template<typename Func, - typename enable_if_return<Func, pm_any_t>::type * = nullptr, - typename function_traits<Func>::empty_arg * = nullptr> - constexpr auto gen_on_fulfilled(Func on_fulfilled, const promise_t &npm) { - return [npm, on_fulfilled = std::forward<Func>(on_fulfilled)]() mutable { - npm->_resolve(on_fulfilled()); - }; - } - - template<typename Func, - typename enable_if_return<Func, pm_any_t>::type * = nullptr, - typename function_traits<Func>::non_empty_arg * = nullptr> - constexpr auto gen_on_rejected(Func on_rejected, const promise_t &npm) { - return [this, npm, on_rejected = std::forward<Func>(on_rejected)]() mutable { - npm->_reject(on_rejected(reason)); - }; - } - - template<typename Func, - typename enable_if_return<Func, pm_any_t>::type * = nullptr, - typename function_traits<Func>::empty_arg * = nullptr> - constexpr auto gen_on_rejected(Func on_rejected, const promise_t &npm) { - return [npm, on_rejected = std::forward<Func>(on_rejected)]() mutable { - npm->_reject(on_rejected()); - }; - } - -#ifdef CPPROMISE_USE_STACK_FREE - void _trigger() { - std::stack<std::tuple< - std::vector<Promise *>::const_iterator, - std::vector<Promise *> *, - Promise *>> s; - auto push_frame = [&s](Promise *pm) { - if (pm->state == State::PreFulfilled) - { - pm->state = State::Fulfilled; - for (auto &cb: pm->fulfilled_callbacks) cb(); - s.push(std::make_tuple(pm->fulfilled_pms.begin(), - &pm->fulfilled_pms, - pm)); - } - else if (pm->state == State::PreRejected) - { - pm->state = State::Rejected; - for (auto &cb: pm->rejected_callbacks) cb(); - s.push(std::make_tuple(pm->rejected_pms.begin(), - &pm->rejected_pms, - pm)); - } - }; - push_frame(this); - while (!s.empty()) - { - auto &u = s.top(); - auto &it = std::get<0>(u); - auto vec = std::get<1>(u); - auto pm = std::get<2>(u); - if (it == vec->end()) - { - s.pop(); - vec->clear(); - pm->fulfilled_callbacks.clear(); - pm->rejected_callbacks.clear(); - continue; - } - push_frame(*it++); - } - } - - void trigger_fulfill() { - state = State::PreFulfilled; - _trigger(); - } - - void trigger_reject() { - state = State::PreRejected; - _trigger(); - } - - void _resolve() { - if (state == State::Pending) state = State::PreFulfilled; - } - - void _reject() { - if (state == State::Pending) state = State::PreRejected; - } - - void _dep_resolve(const promise_t &npm) { - if (state == State::Pending) - fulfilled_pms.push_back(npm.pm); - else - npm->_trigger(); - } - - void _dep_reject(const promise_t &npm) { - if (state == State::Pending) - rejected_pms.push_back(npm.pm); - else - npm->_trigger(); - } - - void _resolve(pm_any_t _result) { - if (state == State::Pending) - { - result = _result; - state = State::PreFulfilled; - } - } - - void _reject(pm_any_t _reason) { - if (state == State::Pending) - { - reason = _reason; - state = State::PreRejected; - } - } -#else - void _resolve() { resolve(); } - void _reject() { reject(); } - void _resolve(pm_any_t result) { resolve(result); } - void _reject(pm_any_t reason) { reject(reason); } - - void trigger_fulfill() { - state = State::Fulfilled; - for (const auto &cb: fulfilled_callbacks) cb(); - fulfilled_callbacks.clear(); - } - - void trigger_reject() { - state = State::Rejected; - for (const auto &cb: rejected_callbacks) cb(); - rejected_callbacks.clear(); - } -#endif - public: - - Promise(): state(State::Pending) {} - ~Promise() {} - - template<typename FuncFulfilled, typename FuncRejected> - promise_t then(FuncFulfilled on_fulfilled, - FuncRejected on_rejected) { - switch (state) - { - case State::Pending: - return promise_t([this, - on_fulfilled = std::forward<FuncFulfilled>(on_fulfilled), - on_rejected = std::forward<FuncRejected>(on_rejected) - ](promise_t &npm) { - add_on_fulfilled(gen_on_fulfilled(std::move(on_fulfilled), npm)); - add_on_rejected(gen_on_rejected(std::move(on_rejected), npm)); -#ifdef CPPROMISE_USE_STACK_FREE - _dep_resolve(npm); - _dep_reject(npm); -#endif - }); - case State::Fulfilled: - return promise_t([this, - on_fulfilled = std::forward<FuncFulfilled>(on_fulfilled) - ](promise_t &npm) { - gen_on_fulfilled(std::move(on_fulfilled), npm)(); - }); - case State::Rejected: - return promise_t([this, - on_rejected = std::forward<FuncRejected>(on_rejected) - ](promise_t &npm) { - gen_on_rejected(std::move(on_rejected), npm)(); - }); - default: PROMISE_ERR_INVALID_STATE; - } - } - - template<typename FuncFulfilled> - promise_t then(FuncFulfilled &&on_fulfilled) { - switch (state) - { - case State::Pending: - return promise_t([this, - on_fulfilled = std::forward<FuncFulfilled>(on_fulfilled) - ](promise_t &npm) { - add_on_fulfilled(gen_on_fulfilled(std::move(on_fulfilled), npm)); - add_on_rejected([this, npm]() {npm->_reject(reason);}); -#ifdef CPPROMISE_USE_STACK_FREE - _dep_resolve(npm); - _dep_reject(npm); -#endif - }); - case State::Fulfilled: - return promise_t([this, - on_fulfilled = std::forward<FuncFulfilled>(on_fulfilled) - ](promise_t &npm) { - gen_on_fulfilled(std::move(on_fulfilled), npm)(); - }); - case State::Rejected: - return promise_t([this](promise_t &npm) {npm->_reject(reason);}); - default: PROMISE_ERR_INVALID_STATE; - } - } - - template<typename FuncRejected> - promise_t fail(FuncRejected &&on_rejected) { - switch (state) - { - case State::Pending: - return promise_t([this, - on_rejected = std::forward<FuncRejected>(on_rejected) - ](promise_t &npm) { - callback_t ret; - add_on_rejected(gen_on_rejected(std::move(on_rejected), npm)); - add_on_fulfilled([this, npm]() {npm->_resolve(result);}); -#ifdef CPPROMISE_USE_STACK_FREE - _dep_resolve(npm); - _dep_reject(npm); -#endif - }); - case State::Fulfilled: - return promise_t([this](promise_t &npm) {npm->_resolve(result);}); - case State::Rejected: - return promise_t([this, - on_rejected = std::forward<FuncRejected>(on_rejected) - ](promise_t &npm) { - gen_on_rejected(std::move(on_rejected), npm)(); - }); - default: PROMISE_ERR_INVALID_STATE; - } - } - - void resolve() { - if (state == State::Pending) trigger_fulfill(); - } - - void reject() { - if (state == State::Pending) trigger_reject(); - } - - void resolve(pm_any_t _result) { - if (state == State::Pending) - { - result = _result; - trigger_fulfill(); - } - } - - void reject(pm_any_t _reason) { - if (state == State::Pending) - { - reason = _reason; - trigger_reject(); - } - } - }; - - template<typename PList> promise_t all(const PList &promise_list) { - return promise_t([&promise_list] (promise_t &npm) { - auto size = std::make_shared<size_t>(promise_list.size()); - auto results = std::make_shared<values_t>(); - if (!*size) PROMISE_ERR_MISMATCH_TYPE; - results->resize(*size); - size_t idx = 0; - for (const auto &pm: promise_list) { - pm->then( - [results, size, idx, npm](pm_any_t result) { - (*results)[idx] = result; - if (!--(*size)) - npm->_resolve(*results); - }, - [npm](pm_any_t reason) {npm->_reject(reason);}); -#ifdef CPPROMISE_USE_STACK_FREE - pm->_dep_resolve(npm); - pm->_dep_reject(npm); -#endif - idx++; - } - }); - } - - template<typename PList> promise_t race(const PList &promise_list) { - return promise_t([&promise_list] (promise_t &npm) { - for (const auto &pm: promise_list) { - pm->then([npm](pm_any_t result) {npm->_resolve(result);}, - [npm](pm_any_t reason) {npm->_reject(reason);}); -#ifdef CPPROMISE_USE_STACK_FREE - pm->_dep_resolve(npm); - pm->_dep_reject(npm); -#endif - } - }); - } - - template<typename Func> - inline promise_t::promise_t(Func callback): - pm(new Promise()), - ref_cnt(new size_t(1)) { - callback(*this); - } - - inline promise_t::promise_t(): - pm(new Promise()), - ref_cnt(new size_t(1)) {} - - inline promise_t::~promise_t() { - if (pm) - { - if (--*ref_cnt) return; - delete pm; - delete ref_cnt; - } - } - - template<typename T> - inline void promise_t::resolve(T result) const { (*this)->resolve(result); } - - template<typename T> - inline void promise_t::reject(T reason) const { (*this)->reject(reason); } - - inline void promise_t::resolve() const { (*this)->resolve(); } - inline void promise_t::reject() const { (*this)->reject(); } - - template<typename T> - struct callback_types { - using arg_type = typename function_traits<T>::arg_type; - using ret_type = typename std::conditional< - std::is_same<typename function_traits<T>::ret_type, promise_t>::value, - promise_t, pm_any_t>::type; - }; - - template<typename Func, - typename disable_if_arg<Func, pm_any_t>::type * = nullptr, - typename enable_if_return<Func, void>::type * = nullptr, - typename function_traits<Func>::non_empty_arg * = nullptr> - constexpr auto gen_any_callback(Func f) { - using func_t = callback_types<Func>; - return [f = std::forward<Func>(f)](pm_any_t v) mutable { - try { - f(any_cast<typename func_t::arg_type>(v)); - } catch (bad_any_cast &e) { PROMISE_ERR_MISMATCH_TYPE; } - }; - } - - template<typename Func, - typename enable_if_arg<Func, pm_any_t>::type * = nullptr, - typename enable_if_return<Func, void>::type * = nullptr, - typename function_traits<Func>::non_empty_arg * = nullptr> - constexpr auto gen_any_callback(Func f) { - return [f = std::forward<Func>(f)](pm_any_t v) mutable {f(v);}; - } - - template<typename Func, - typename enable_if_return<Func, void>::type * = nullptr, - typename function_traits<Func>::empty_arg * = nullptr> - constexpr auto gen_any_callback(Func f) { return std::forward<Func>(f); } - - template<typename Func, - typename enable_if_arg<Func, pm_any_t>::type * = nullptr, - typename disable_if_return<Func, void>::type * = nullptr, - typename function_traits<Func>::non_empty_arg * = nullptr> - constexpr auto gen_any_callback(Func f) { - using func_t = callback_types<Func>; - return [f = std::forward<Func>(f)](pm_any_t v) mutable { - return typename func_t::ret_type(f(v)); - }; - } - - template<typename Func, - typename disable_if_arg<Func, pm_any_t>::type * = nullptr, - typename disable_if_return<Func, void>::type * = nullptr, - typename function_traits<Func>::non_empty_arg * = nullptr> - constexpr auto gen_any_callback(Func f) { - using func_t = callback_types<Func>; - return [f = std::forward<Func>(f)](pm_any_t v) mutable { - try { - return typename func_t::ret_type( - f(any_cast<typename func_t::arg_type>(v))); - } catch (bad_any_cast &e) { PROMISE_ERR_MISMATCH_TYPE; } - }; - } - - template<typename Func, - typename disable_if_return<Func, void>::type * = nullptr, - typename function_traits<Func>::empty_arg * = nullptr> - constexpr auto gen_any_callback(Func f) { - using func_t = callback_types<Func>; - return [f = std::forward<Func>(f)]() mutable { - return typename func_t::ret_type(f()); - }; - } - - template<typename FuncFulfilled> - inline promise_t promise_t::then(FuncFulfilled on_fulfilled) const { - return (*this)->then(gen_any_callback(std::forward<FuncFulfilled>(on_fulfilled))); - } - - template<typename FuncFulfilled, typename FuncRejected> - inline promise_t promise_t::then(FuncFulfilled on_fulfilled, - FuncRejected on_rejected) const { - return (*this)->then(gen_any_callback(std::forward<FuncFulfilled>(on_fulfilled)), - gen_any_callback(std::forward<FuncRejected>(on_rejected))); - } - - template<typename FuncRejected> - inline promise_t promise_t::fail(FuncRejected on_rejected) const { - return (*this)->fail(gen_any_callback(std::forward<FuncRejected>(on_rejected))); - } -} - -#endif |