-/* Copyright (c) 2016-2019. The SimGrid Team.
+/* Copyright (c) 2016-2022. The SimGrid Team.
* All rights reserved. */
/* This program is free software; you can redistribute it and/or modify it
#include <xbt/base.h>
#include <xbt/functional.hpp>
-#include <xbt/future.hpp>
+#include <xbt/promise.hpp>
namespace simgrid {
namespace kernel {
FutureStateBase(FutureStateBase const&) = delete;
FutureStateBase& operator=(FutureStateBase const&) = delete;
- XBT_PUBLIC void schedule(simgrid::xbt::Task<void()>&& job);
+ XBT_PUBLIC void schedule(simgrid::xbt::Task<void()>&& job) const;
void set_exception(std::exception_ptr exception)
{
schedule(std::move(continuation));
break;
case FutureStatus::not_ready:
- // The future is not ready so we mast keep the continuation for
+ // The future is not ready so we must keep the continuation for
// executing it later:
continuation_ = std::move(continuation);
break;
status_ = FutureStatus::ready;
if (continuation_) {
// We unregister the continuation before executing it.
- // We need to do this becase the current implementation of the
+ // We need to do this because the current implementation of the
// continuation has a shared_ptr to the FutureState.
auto continuation = std::move(continuation_);
this->schedule(std::move(continuation));
**/
void resolve()
{
- if (status_ != FutureStatus::ready)
- xbt_die("Deadlock: this future is not ready");
+ xbt_assert(status_ == FutureStatus::ready, "Deadlock: this future is not ready");
status_ = FutureStatus::done;
if (exception_) {
std::exception_ptr exception = std::move(exception_);
/** Shared state for future and promises
*
* You are not expected to use them directly but to create them
- * implicitely through a @ref simgrid::kernel::Promise.
+ * implicitly through a @ref simgrid::kernel::Promise.
* Alternatively kernel operations could inherit or contain FutureState
* if they are managed with std::shared_ptr.
**/
template<class T>
class FutureState : public FutureStateBase {
public:
-
void set_value(T value)
{
if (this->get_status() != FutureStatus::not_ready)
/** Result of some (probably) asynchronous operation in the SimGrid kernel
*
* @ref simgrid::simix::Future and @ref simgrid::simix::Future provide an
- * abstration for asynchronous stuff happening in the SimGrid kernel. They
+ * abstraction for asynchronous stuff happening in the SimGrid kernel. They
* are based on C++1z futures.
*
* The future represents a value which will be available at some point when this
- * asynchronous operaiont is finished. Alternatively, if this operations fails,
+ * asynchronous operation is finished. Alternatively, if this operations fails,
* the result of the operation might be an exception.
*
* As the operation is possibly no terminated yet, we cannot get the result
* // available:
* try {
* // Try to get value, this might throw an exception if the operation
- * // failed (such as an exception throwed by the worker process):
+ * // failed (such as an exception thrown by the worker process):
* std::string value = result.get();
* XBT_INFO("Value: %s", value.c_str());
* }
* * inside the `.then()`, `.get()` can be used;
*
* * `.get()` can only be used when `.is_ready()` (as everything happens in
- * a single-thread, the future would be guaranted to deadlock if `.get()`
+ * a single-thread, the future would be guaranteed to deadlock if `.get()`
* is called when the future is not ready);
*
* * there is no future chaining support for now (`.then().then()`);
public:
Future() = default;
explicit Future(std::shared_ptr<FutureState<T>> state) : state_(std::move(state)) {}
- ~Future() = default;
// Move type:
Future(Future&) = delete;
- Future& operator=(Future&) = delete;
- Future(Future&& that) : state_(std::move(that.state_)) {}
- Future& operator=(Future&& that)
- {
- state_ = std::move(that.state_);
- return *this;
- }
+ Future& operator=(const Future&) = delete;
+ Future(Future&&) noexcept = default;
+ Future& operator=(Future&&) noexcept = default;
/** Whether the future is valid:.
*
*/
template <class F> auto then_no_unwrap(F continuation) -> Future<decltype(continuation(std::move(*this)))>
{
- typedef decltype(continuation(std::move(*this))) R;
+ using R = decltype(continuation(std::move(*this)));
if (state_ == nullptr)
throw std::future_error(std::future_errc::no_state);
auto state = std::move(state_);
* @exception std::future_error no state is associated with the future
*/
template <class F>
- auto then(F continuation) -> typename std::enable_if<not is_future<decltype(continuation(std::move(*this)))>::value,
- Future<decltype(continuation(std::move(*this)))>>::type
+ auto then(F continuation) -> typename std::enable_if_t<not is_future<decltype(continuation(std::move(*this)))>::value,
+ Future<decltype(continuation(std::move(*this)))>>
{
return this->then_no_unwrap(std::move(continuation));
}
/** Attach a continuation to this future (future chaining) */
- template<class F>
- auto then(F continuation)
- -> typename std::enable_if<
- is_future<decltype(continuation(std::move(*this)))>::value,
- decltype(continuation(std::move(*this)))
- >::type
+ template <class F>
+ auto then(F continuation) -> typename std::enable_if_t<is_future<decltype(continuation(std::move(*this)))>::value,
+ decltype(continuation(std::move(*this)))>
{
return unwrap_future(this->then_no_unwrap(std::move(continuation)));
}
* auto promise = std::make_shared<simgrid::kernel::Promise<T>>();
* auto future = promise->get_future();
*
- * simgrid::simix::Timer::set(date, [promise] {
+ * simgrid::kernel::timer::Timer::set(date, [promise] {
* try {
* int value = compute_the_value();
* if (value < 0)
* promise.set_value(value);
* }
* catch (...) {
- * // If an error occured, we can set an exception which
- * // will be throwed buy future.get():
+ * // If an error occurred, we can set an exception which
+ * // will be thrown by future.get():
* promise.set_exception(std::current_exception());
* }
* });
template<class T>
class Promise {
public:
- Promise() : state_(std::make_shared<FutureState<T>>()) {}
+ Promise() = default;
explicit Promise(std::shared_ptr<FutureState<T>> state) : state_(std::move(state)) {}
// Move type
Promise(Promise const&) = delete;
Promise& operator=(Promise const&) = delete;
- Promise(Promise&& that) :
- state_(std::move(that.state_)), future_get_(that.future_get_)
- {
- that.future_get_ = false;
- }
+ Promise(Promise&& that) noexcept : state_(std::move(that.state_)) { std::swap(future_get_, that.future_get_); }
- Promise& operator=(Promise&& that)
+ Promise& operator=(Promise&& that) noexcept
{
this->state_ = std::move(that.state_);
this->future_get_ = that.future_get_;
}
private:
- std::shared_ptr<FutureState<T>> state_;
+ std::shared_ptr<FutureState<T>> state_ = std::make_shared<FutureState<T>>();
bool future_get_ = false;
};
template<>
class Promise<void> {
public:
- Promise() : state_(std::make_shared<FutureState<void>>()) {}
+ Promise() = default;
explicit Promise(std::shared_ptr<FutureState<void>> state) : state_(std::move(state)) {}
~Promise()
{
// Move type
Promise(Promise const&) = delete;
Promise& operator=(Promise const&) = delete;
- Promise(Promise&& that) :
- state_(std::move(that.state_)), future_get_(that.future_get_)
- {
- that.future_get_ = false;
- }
- Promise& operator=(Promise&& that)
+ Promise(Promise&& that) noexcept : state_(std::move(that.state_)) { std::swap(future_get_, that.future_get_); }
+ Promise& operator=(Promise&& that) noexcept
{
this->state_ = std::move(that.state_);
this->future_get_ = that.future_get_;
future_get_ = true;
return Future<void>(state_);
}
- void set_value()
+ void set_value() const
{
if (state_ == nullptr)
throw std::future_error(std::future_errc::no_state);
state_->set_value();
}
- void set_exception(std::exception_ptr exception)
+ void set_exception(std::exception_ptr exception) const
{
if (state_ == nullptr)
throw std::future_error(std::future_errc::no_state);
}
private:
- std::shared_ptr<FutureState<void>> state_;
+ std::shared_ptr<FutureState<void>> state_ = std::make_shared<FutureState<void>>();
bool future_get_ = false;
};
