654 lines
16 KiB
C++
654 lines
16 KiB
C++
//
|
|
// Copyright Aliaksei Levin (levlam@telegram.org), Arseny Smirnov (arseny30@gmail.com) 2014-2018
|
|
//
|
|
// Distributed under the Boost Software License, Version 1.0. (See accompanying
|
|
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
|
|
//
|
|
#pragma once
|
|
|
|
#include "td/actor/actor.h"
|
|
|
|
#include "td/utils/Closure.h"
|
|
#include "td/utils/common.h"
|
|
#include "td/utils/invoke.h" // for tuple_for_each
|
|
#include "td/utils/logging.h"
|
|
#include "td/utils/ScopeGuard.h"
|
|
#include "td/utils/Status.h"
|
|
|
|
#include <tuple>
|
|
#include <type_traits>
|
|
#include <utility>
|
|
|
|
namespace td {
|
|
template <class T = Unit>
|
|
class PromiseInterface {
|
|
public:
|
|
PromiseInterface() = default;
|
|
PromiseInterface(const PromiseInterface &) = delete;
|
|
PromiseInterface &operator=(const PromiseInterface &) = delete;
|
|
PromiseInterface(PromiseInterface &&) = default;
|
|
PromiseInterface &operator=(PromiseInterface &&) = default;
|
|
virtual ~PromiseInterface() = default;
|
|
virtual void set_value(T &&value) {
|
|
set_result(std::move(value));
|
|
}
|
|
virtual void set_error(Status &&error) {
|
|
set_result(std::move(error));
|
|
}
|
|
virtual void set_result(Result<T> &&result) {
|
|
if (result.is_ok()) {
|
|
set_value(result.move_as_ok());
|
|
} else {
|
|
set_error(result.move_as_error());
|
|
}
|
|
}
|
|
virtual bool is_cancellable() const {
|
|
return false;
|
|
}
|
|
virtual bool is_cancelled() const {
|
|
return false;
|
|
}
|
|
|
|
virtual void start_migrate(int32 sched_id) {
|
|
}
|
|
virtual void finish_migrate() {
|
|
}
|
|
};
|
|
|
|
template <class T = Unit>
|
|
class FutureInterface {
|
|
public:
|
|
FutureInterface() = default;
|
|
FutureInterface(const FutureInterface &) = delete;
|
|
FutureInterface &operator=(const FutureInterface &) = delete;
|
|
FutureInterface(FutureInterface &&) = default;
|
|
FutureInterface &operator=(FutureInterface &&) = default;
|
|
virtual ~FutureInterface() = default;
|
|
virtual bool is_ready() = 0;
|
|
virtual bool is_ok() = 0;
|
|
virtual bool is_error() = 0;
|
|
virtual const T &ok() = 0;
|
|
virtual T move_as_ok() = 0;
|
|
virtual const Status &error() = 0;
|
|
virtual Status move_as_error() TD_WARN_UNUSED_RESULT = 0;
|
|
virtual const Result<T> &result() = 0;
|
|
virtual Result<T> move_as_result() TD_WARN_UNUSED_RESULT = 0;
|
|
};
|
|
|
|
template <class T>
|
|
class SafePromise;
|
|
|
|
template <class T = Unit>
|
|
class Promise {
|
|
public:
|
|
void set_value(T &&value) {
|
|
if (!promise_) {
|
|
return;
|
|
}
|
|
promise_->set_value(std::move(value));
|
|
promise_.reset();
|
|
}
|
|
void set_error(Status &&error) {
|
|
if (!promise_) {
|
|
return;
|
|
}
|
|
promise_->set_error(std::move(error));
|
|
promise_.reset();
|
|
}
|
|
void set_result(Result<T> &&result) {
|
|
if (!promise_) {
|
|
return;
|
|
}
|
|
promise_->set_result(std::move(result));
|
|
promise_.reset();
|
|
}
|
|
void reset() {
|
|
promise_.reset();
|
|
}
|
|
void start_migrate(int32 sched_id) {
|
|
if (!promise_) {
|
|
return;
|
|
}
|
|
promise_->start_migrate(sched_id);
|
|
}
|
|
void finish_migrate() {
|
|
if (!promise_) {
|
|
return;
|
|
}
|
|
promise_->finish_migrate();
|
|
}
|
|
bool is_cancellable() const {
|
|
if (!promise_) {
|
|
return false;
|
|
}
|
|
return promise_->is_cancellable();
|
|
}
|
|
bool is_cancelled() const {
|
|
if (!promise_) {
|
|
return false;
|
|
}
|
|
return promise_->is_cancelled();
|
|
}
|
|
std::unique_ptr<PromiseInterface<T>> release() {
|
|
return std::move(promise_);
|
|
}
|
|
|
|
Promise() = default;
|
|
explicit Promise(std::unique_ptr<PromiseInterface<T>> promise) : promise_(std::move(promise)) {
|
|
}
|
|
Promise(SafePromise<T> &&other);
|
|
Promise &operator=(SafePromise<T> &&other);
|
|
|
|
explicit operator bool() {
|
|
return static_cast<bool>(promise_);
|
|
}
|
|
|
|
private:
|
|
std::unique_ptr<PromiseInterface<T>> promise_;
|
|
};
|
|
|
|
template <class T>
|
|
void start_migrate(Promise<T> &promise, int32 sched_id) {
|
|
// promise.start_migrate(sched_id);
|
|
}
|
|
template <class T>
|
|
void finish_migrate(Promise<T> &promise) {
|
|
// promise.finish_migrate();
|
|
}
|
|
|
|
template <class T = Unit>
|
|
class SafePromise {
|
|
public:
|
|
SafePromise(Promise<T> promise, Result<T> result) : promise_(std::move(promise)), result_(std::move(result)) {
|
|
}
|
|
SafePromise(const SafePromise &other) = delete;
|
|
SafePromise &operator=(const SafePromise &other) = delete;
|
|
SafePromise(SafePromise &&other) = default;
|
|
SafePromise &operator=(SafePromise &&other) = default;
|
|
~SafePromise() {
|
|
if (promise_) {
|
|
promise_.set_result(std::move(result_));
|
|
}
|
|
}
|
|
Promise<T> release() {
|
|
return std::move(promise_);
|
|
}
|
|
|
|
private:
|
|
Promise<T> promise_;
|
|
Result<T> result_;
|
|
};
|
|
|
|
template <class T>
|
|
Promise<T>::Promise(SafePromise<T> &&other) : Promise(other.release()) {
|
|
}
|
|
template <class T>
|
|
Promise<T> &Promise<T>::operator=(SafePromise<T> &&other) {
|
|
*this = other.release();
|
|
return *this;
|
|
}
|
|
|
|
class CancellationToken {
|
|
public:
|
|
explicit CancellationToken(bool init = false) {
|
|
if (init) {
|
|
ptr_ = std::make_shared<std::atomic<bool>>(false);
|
|
}
|
|
}
|
|
CancellationToken(const CancellationToken &other) = default;
|
|
CancellationToken &operator=(const CancellationToken &other) {
|
|
cancel();
|
|
ptr_ = other.ptr_;
|
|
return *this;
|
|
}
|
|
CancellationToken(CancellationToken &&other) = default;
|
|
CancellationToken &operator=(CancellationToken &&other) {
|
|
cancel();
|
|
ptr_ = std::move(other.ptr_);
|
|
return *this;
|
|
}
|
|
~CancellationToken() {
|
|
cancel();
|
|
}
|
|
bool is_canceled() const {
|
|
return !ptr_ || *ptr_;
|
|
}
|
|
void cancel() {
|
|
if (ptr_) {
|
|
ptr_->store(true, std::memory_order_relaxed);
|
|
ptr_.reset();
|
|
}
|
|
}
|
|
|
|
private:
|
|
std::shared_ptr<std::atomic<bool>> ptr_;
|
|
};
|
|
|
|
namespace detail {
|
|
|
|
class EventPromise : public PromiseInterface<Unit> {
|
|
public:
|
|
void set_value(Unit &&) override {
|
|
ok_.try_emit();
|
|
fail_.clear();
|
|
}
|
|
void set_error(Status &&) override {
|
|
do_set_error();
|
|
}
|
|
|
|
EventPromise(const EventPromise &other) = delete;
|
|
EventPromise &operator=(const EventPromise &other) = delete;
|
|
EventPromise(EventPromise &&other) = delete;
|
|
EventPromise &operator=(EventPromise &&other) = delete;
|
|
~EventPromise() override {
|
|
do_set_error();
|
|
}
|
|
|
|
EventPromise() = default;
|
|
explicit EventPromise(EventFull ok) : ok_(std::move(ok)), use_ok_as_fail_(true) {
|
|
}
|
|
EventPromise(EventFull ok, EventFull fail) : ok_(std::move(ok)), fail_(std::move(fail)), use_ok_as_fail_(false) {
|
|
}
|
|
|
|
private:
|
|
EventFull ok_;
|
|
EventFull fail_;
|
|
bool use_ok_as_fail_ = false;
|
|
void do_set_error() {
|
|
if (use_ok_as_fail_) {
|
|
ok_.try_emit();
|
|
} else {
|
|
ok_.clear();
|
|
fail_.try_emit();
|
|
}
|
|
}
|
|
};
|
|
|
|
template <typename T>
|
|
struct GetArg : public GetArg<decltype(&T::operator())> {};
|
|
|
|
template <class C, class R, class Arg>
|
|
class GetArg<R (C::*)(Arg)> {
|
|
public:
|
|
using type = Arg;
|
|
};
|
|
template <class C, class R, class Arg>
|
|
class GetArg<R (C::*)(Arg) const> {
|
|
public:
|
|
using type = Arg;
|
|
};
|
|
|
|
template <class T>
|
|
using get_arg_t = std::decay_t<typename GetArg<T>::type>;
|
|
|
|
template <class T>
|
|
struct DropResult {
|
|
using type = T;
|
|
};
|
|
|
|
template <class T>
|
|
struct DropResult<Result<T>> {
|
|
using type = T;
|
|
};
|
|
|
|
template <class T>
|
|
using drop_result_t = typename DropResult<T>::type;
|
|
|
|
template <class PromiseT>
|
|
class CancellablePromise : public PromiseT {
|
|
public:
|
|
template <class... ArgsT>
|
|
CancellablePromise(CancellationToken cancellation_token, ArgsT &&... args)
|
|
: PromiseT(std::forward<ArgsT>(args)...), cancellation_token_(std::move(cancellation_token)) {
|
|
}
|
|
virtual bool is_cancellable() const {
|
|
return true;
|
|
;
|
|
}
|
|
virtual bool is_cancelled() const {
|
|
return cancellation_token_.is_canceled();
|
|
}
|
|
|
|
private:
|
|
CancellationToken cancellation_token_;
|
|
};
|
|
|
|
template <class ValueT, class FunctionOkT, class FunctionFailT>
|
|
class LambdaPromise : public PromiseInterface<ValueT> {
|
|
enum OnFail { None, Ok, Fail };
|
|
|
|
public:
|
|
void set_value(ValueT &&value) override {
|
|
ok_(std::move(value));
|
|
on_fail_ = None;
|
|
}
|
|
void set_error(Status &&error) override {
|
|
do_error(std::move(error));
|
|
}
|
|
LambdaPromise(const LambdaPromise &other) = delete;
|
|
LambdaPromise &operator=(const LambdaPromise &other) = delete;
|
|
LambdaPromise(LambdaPromise &&other) = delete;
|
|
LambdaPromise &operator=(LambdaPromise &&other) = delete;
|
|
~LambdaPromise() override {
|
|
do_error(Status::Error("Lost promise"));
|
|
}
|
|
|
|
template <class FromOkT, class FromFailT>
|
|
LambdaPromise(FromOkT &&ok, FromFailT &&fail, bool use_ok_as_fail)
|
|
: ok_(std::forward<FromOkT>(ok)), fail_(std::forward<FromFailT>(fail)), on_fail_(use_ok_as_fail ? Ok : Fail) {
|
|
}
|
|
|
|
private:
|
|
FunctionOkT ok_;
|
|
FunctionFailT fail_;
|
|
OnFail on_fail_ = None;
|
|
|
|
template <class FuncT, class ArgT = detail::get_arg_t<FuncT>>
|
|
std::enable_if_t<std::is_assignable<ArgT, Status>::value> do_error_impl(FuncT &func, Status &&status) {
|
|
func(std::move(status));
|
|
}
|
|
|
|
template <class FuncT, class ArgT = detail::get_arg_t<FuncT>>
|
|
std::enable_if_t<!std::is_assignable<ArgT, Status>::value> do_error_impl(FuncT &func, Status &&status) {
|
|
func(Auto());
|
|
}
|
|
|
|
void do_error(Status &&error) {
|
|
switch (on_fail_) {
|
|
case None:
|
|
break;
|
|
case Ok:
|
|
do_error_impl(ok_, std::move(error));
|
|
break;
|
|
case Fail:
|
|
fail_(std::move(error));
|
|
break;
|
|
}
|
|
on_fail_ = None;
|
|
}
|
|
};
|
|
|
|
template <class... ArgsT>
|
|
class JoinPromise : public PromiseInterface<Unit> {
|
|
public:
|
|
explicit JoinPromise(ArgsT &&... arg) : promises_(std::forward<ArgsT>(arg)...) {
|
|
}
|
|
void set_value(Unit &&) override {
|
|
tuple_for_each(promises_, [](auto &promise) { promise.set_value(Unit()); });
|
|
}
|
|
void set_error(Status &&error) override {
|
|
tuple_for_each(promises_, [&error](auto &promise) { promise.set_error(error.clone()); });
|
|
}
|
|
|
|
private:
|
|
std::tuple<std::decay_t<ArgsT>...> promises_;
|
|
};
|
|
} // namespace detail
|
|
|
|
/*** FutureActor and PromiseActor ***/
|
|
template <class T>
|
|
class FutureActor;
|
|
|
|
template <class T>
|
|
class PromiseActor;
|
|
|
|
template <class T>
|
|
class ActorTraits<FutureActor<T>> {
|
|
public:
|
|
static constexpr bool is_lite = true;
|
|
};
|
|
|
|
template <class T>
|
|
class PromiseActor final : public PromiseInterface<T> {
|
|
friend class FutureActor<T>;
|
|
enum State { Waiting, Hangup };
|
|
|
|
public:
|
|
PromiseActor() = default;
|
|
PromiseActor(const PromiseActor &other) = delete;
|
|
PromiseActor &operator=(const PromiseActor &other) = delete;
|
|
PromiseActor(PromiseActor &&) = default;
|
|
PromiseActor &operator=(PromiseActor &&) = default;
|
|
~PromiseActor() override {
|
|
close();
|
|
}
|
|
|
|
void set_value(T &&value) override;
|
|
void set_error(Status &&error) override;
|
|
|
|
void close() {
|
|
future_id_.reset();
|
|
}
|
|
|
|
// NB: if true is returned no further events will be sent
|
|
bool is_hangup() {
|
|
if (state_ == State::Hangup) {
|
|
return true;
|
|
}
|
|
if (!future_id_.is_alive()) {
|
|
state_ = State::Hangup;
|
|
future_id_.release();
|
|
event_.clear();
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
template <class S>
|
|
friend void init_promise_future(PromiseActor<S> *promise, FutureActor<S> *future);
|
|
|
|
bool empty_promise() {
|
|
return future_id_.empty();
|
|
}
|
|
bool empty() {
|
|
return future_id_.empty();
|
|
}
|
|
|
|
private:
|
|
ActorOwn<FutureActor<T>> future_id_;
|
|
EventFull event_;
|
|
State state_;
|
|
|
|
void init() {
|
|
state_ = State::Waiting;
|
|
event_.clear();
|
|
}
|
|
};
|
|
|
|
template <class T>
|
|
class FutureActor final : public Actor {
|
|
friend class PromiseActor<T>;
|
|
enum State { Waiting, Ready };
|
|
|
|
public:
|
|
static constexpr int Hangup = 426487;
|
|
|
|
FutureActor() = default;
|
|
|
|
FutureActor(const FutureActor &other) = delete;
|
|
FutureActor &operator=(const FutureActor &other) = delete;
|
|
|
|
FutureActor(FutureActor &&other) = default;
|
|
FutureActor &operator=(FutureActor &&other) = default;
|
|
|
|
~FutureActor() override = default;
|
|
|
|
bool is_ok() const {
|
|
return is_ready() && result_.is_ok();
|
|
}
|
|
bool is_error() const {
|
|
CHECK(is_ready());
|
|
return is_ready() && result_.is_error();
|
|
}
|
|
T move_as_ok() {
|
|
return move_as_result().move_as_ok();
|
|
}
|
|
Status move_as_error() TD_WARN_UNUSED_RESULT {
|
|
return move_as_result().move_as_error();
|
|
}
|
|
Result<T> move_as_result() TD_WARN_UNUSED_RESULT {
|
|
CHECK(is_ready());
|
|
SCOPE_EXIT {
|
|
do_stop();
|
|
};
|
|
return std::move(result_);
|
|
}
|
|
bool is_ready() const {
|
|
return !empty() && state_ == State::Ready;
|
|
}
|
|
|
|
void close() {
|
|
event_.clear();
|
|
result_.clear();
|
|
do_stop();
|
|
}
|
|
|
|
void set_event(EventFull &&event) {
|
|
CHECK(!empty());
|
|
event_ = std::move(event);
|
|
if (state_ != State::Waiting) {
|
|
event_.try_emit_later();
|
|
}
|
|
}
|
|
|
|
template <class S>
|
|
friend void init_promise_future(PromiseActor<S> *promise, FutureActor<S> *future);
|
|
|
|
private:
|
|
EventFull event_;
|
|
Result<T> result_;
|
|
State state_;
|
|
|
|
void set_value(T &&value) {
|
|
set_result(std::move(value));
|
|
}
|
|
|
|
void set_error(Status &&error) {
|
|
set_result(std::move(error));
|
|
}
|
|
|
|
void set_result(Result<T> &&result) {
|
|
CHECK(state_ == State::Waiting);
|
|
result_ = std::move(result);
|
|
state_ = State::Ready;
|
|
|
|
event_.try_emit_later();
|
|
}
|
|
|
|
void hangup() override {
|
|
set_error(Status::Error<Hangup>());
|
|
}
|
|
|
|
void start_up() override {
|
|
// empty
|
|
}
|
|
|
|
void init() {
|
|
CHECK(empty());
|
|
state_ = State::Waiting;
|
|
event_.clear();
|
|
}
|
|
};
|
|
|
|
template <class T>
|
|
void PromiseActor<T>::set_value(T &&value) {
|
|
if (state_ == State::Waiting && !future_id_.empty()) {
|
|
send_closure(std::move(future_id_), &FutureActor<T>::set_value, std::move(value));
|
|
}
|
|
}
|
|
template <class T>
|
|
void PromiseActor<T>::set_error(Status &&error) {
|
|
if (state_ == State::Waiting && !future_id_.empty()) {
|
|
send_closure(std::move(future_id_), &FutureActor<T>::set_error, std::move(error));
|
|
}
|
|
}
|
|
|
|
template <class S>
|
|
void init_promise_future(PromiseActor<S> *promise, FutureActor<S> *future) {
|
|
promise->init();
|
|
future->init();
|
|
promise->future_id_ = register_actor("FutureActor", future);
|
|
|
|
CHECK(future->get_info() != nullptr);
|
|
}
|
|
|
|
template <class T>
|
|
class PromiseFuture {
|
|
public:
|
|
PromiseFuture() {
|
|
init_promise_future(&promise_, &future_);
|
|
}
|
|
PromiseActor<T> &promise() {
|
|
return promise_;
|
|
}
|
|
FutureActor<T> &future() {
|
|
return future_;
|
|
}
|
|
PromiseActor<T> &&move_promise() {
|
|
return std::move(promise_);
|
|
}
|
|
FutureActor<T> &&move_future() {
|
|
return std::move(future_);
|
|
}
|
|
|
|
private:
|
|
PromiseActor<T> promise_;
|
|
FutureActor<T> future_;
|
|
};
|
|
|
|
template <class T, class ActorAT, class ActorBT, class ResultT, class... DestArgsT, class... ArgsT>
|
|
FutureActor<T> send_promise(ActorId<ActorAT> actor_id, Send::Flags flags,
|
|
ResultT (ActorBT::*func)(PromiseActor<T> &&, DestArgsT...), ArgsT &&... args) {
|
|
PromiseFuture<T> pf;
|
|
::td::Scheduler::instance()->send_closure(
|
|
std::move(actor_id), create_immediate_closure(func, pf.move_promise(), std::forward<ArgsT>(args)...), flags);
|
|
return pf.move_future();
|
|
}
|
|
|
|
class PromiseCreator {
|
|
public:
|
|
struct Ignore {
|
|
void operator()(Status &&error) {
|
|
error.ignore();
|
|
}
|
|
};
|
|
|
|
template <class OkT, class ArgT = detail::drop_result_t<detail::get_arg_t<OkT>>>
|
|
static Promise<ArgT> lambda(OkT &&ok) {
|
|
return Promise<ArgT>(std::make_unique<detail::LambdaPromise<ArgT, std::decay_t<OkT>, Ignore>>(std::forward<OkT>(ok),
|
|
Ignore(), true));
|
|
}
|
|
|
|
template <class OkT, class FailT, class ArgT = detail::get_arg_t<OkT>>
|
|
static Promise<ArgT> lambda(OkT &&ok, FailT &&fail) {
|
|
return Promise<ArgT>(std::make_unique<detail::LambdaPromise<ArgT, std::decay_t<OkT>, std::decay_t<FailT>>>(
|
|
std::forward<OkT>(ok), std::forward<FailT>(fail), false));
|
|
}
|
|
|
|
template <class OkT, class ArgT = detail::drop_result_t<detail::get_arg_t<OkT>>>
|
|
static auto cancellable_lambda(CancellationToken cancellation_token, OkT &&ok) {
|
|
return Promise<ArgT>(
|
|
std::make_unique<detail::CancellablePromise<detail::LambdaPromise<ArgT, std::decay_t<OkT>, Ignore>>>(
|
|
std::move(cancellation_token), std::forward<OkT>(ok), Ignore(), true));
|
|
}
|
|
|
|
static Promise<> event(EventFull &&ok) {
|
|
return Promise<>(std::make_unique<detail::EventPromise>(std::move(ok)));
|
|
}
|
|
|
|
static Promise<> event(EventFull ok, EventFull fail) {
|
|
return Promise<>(std::make_unique<detail::EventPromise>(std::move(ok), std::move(fail)));
|
|
}
|
|
|
|
template <class... ArgsT>
|
|
static Promise<> join(ArgsT &&... args) {
|
|
return Promise<>(std::make_unique<detail::JoinPromise<ArgsT...>>(std::forward<ArgsT>(args)...));
|
|
}
|
|
|
|
template <class T>
|
|
static Promise<T> from_promise_actor(PromiseActor<T> &&from) {
|
|
return Promise<T>(std::make_unique<PromiseActor<T>>(std::move(from)));
|
|
}
|
|
};
|
|
} // namespace td
|