X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/65beede857f93e33c96e544f76b93793c973dc10..3dd753cd9e46d794e00629d03183250aec4a17e4:/include/simgrid/kernel/future.hpp

diff --git a/include/simgrid/kernel/future.hpp b/include/simgrid/kernel/future.hpp
index fea70d43f0..ac6a4486a3 100644
--- a/include/simgrid/kernel/future.hpp
+++ b/include/simgrid/kernel/future.hpp
@@ -1,4 +1,4 @@
-/* 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
@@ -17,7 +17,7 @@
 
 #include <xbt/base.h>
 #include <xbt/functional.hpp>
-#include <xbt/future.hpp>
+#include <xbt/promise.hpp>
 
 namespace simgrid {
 namespace kernel {
@@ -48,7 +48,7 @@ public:
   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)
   {
@@ -74,7 +74,7 @@ public:
       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;
@@ -103,7 +103,7 @@ protected:
     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));
@@ -116,8 +116,7 @@ protected:
    **/
   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_);
@@ -135,14 +134,13 @@ private:
 /** 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)
@@ -222,11 +220,11 @@ template <class T> Future<T> unwrap_future(Future<Future<T>> future);
 /** 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
@@ -247,7 +245,7 @@ template <class T> Future<T> unwrap_future(Future<Future<T>> future);
  *    // 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());
  *    }
@@ -268,7 +266,7 @@ template <class T> Future<T> unwrap_future(Future<Future<T>> future);
  *  * 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()`);
@@ -280,17 +278,12 @@ class Future {
 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:.
    *
@@ -334,7 +327,7 @@ public:
    */
   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_);
@@ -363,19 +356,16 @@ public:
    * @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)));
   }
@@ -423,7 +413,7 @@ template <class T> Future<T> unwrap_future(Future<Future<T>> future)
  *  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)
@@ -433,8 +423,8 @@ template <class T> Future<T> unwrap_future(Future<Future<T>> future)
  *      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());
  *    }
  *  });
@@ -446,19 +436,15 @@ template <class T> Future<T> unwrap_future(Future<Future<T>> future)
 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_;
@@ -494,14 +480,14 @@ public:
   }
 
 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()
   {
@@ -513,12 +499,8 @@ public:
   // 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_;
@@ -535,13 +517,13 @@ public:
     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);
@@ -549,7 +531,7 @@ public:
   }
 
 private:
-  std::shared_ptr<FutureState<void>> state_;
+  std::shared_ptr<FutureState<void>> state_ = std::make_shared<FutureState<void>>();
   bool future_get_ = false;
 };