Merge branch 'models_type_rework_part2_try2' into 'master'

[simgrid.git] / include / xbt / functional.hpp

diff --git a/include/xbt/functional.hpp b/include/xbt/functional.hpp
index b2d1043..4f5ca2c 100644 (file)
--- a/include/xbt/functional.hpp
+++ b/include/xbt/functional.hpp
@@ -1,4 +1,4 @@
-/* Copyright (c) 2015-2020. The SimGrid Team. All rights reserved.          */
+/* Copyright (c) 2015-2021. The SimGrid Team. All rights reserved.          */
 
 /* This program is free software; you can redistribute it and/or modify it
  * under the terms of the license (GNU LGPL) which comes with this package. */
@@ -12,6 +12,7 @@
 #include <cstdlib>
 #include <cstring>
 
+#include <algorithm>
 #include <array>
 #include <exception>
 #include <functional>
@@ -38,15 +39,9 @@ public:
   {
     const int argc                = args_->size();
     std::vector<std::string> args = *args_;
-    if (not args.empty()) {
-      char noarg[] = {'\0'};
-      auto argv    = std::make_unique<char*[]>(argc + 1);
-      for (int i = 0; i != argc; ++i)
-        argv[i] = args[i].empty() ? noarg : &args[i].front();
-      argv[argc] = nullptr;
-      code_(argc, argv.get());
-    } else
-      code_(argc, nullptr);
+    std::vector<char*> argv(args.size() + 1); // argv[argc] is nullptr
+    std::transform(begin(args), end(args), begin(argv), [](std::string& s) { return &s.front(); });
+    code_(argc, argv.data());
   }
 };
 
@@ -82,11 +77,10 @@ constexpr auto apply(F&& f, Tuple&& t, std::index_sequence<I...>)
 template <class F, class Tuple>
 constexpr auto apply(F&& f, Tuple&& t) -> decltype(
     simgrid::xbt::bits::apply(std::forward<F>(f), std::forward<Tuple>(t),
-                              std::make_index_sequence<std::tuple_size<typename std::decay<Tuple>::type>::value>()))
+                              std::make_index_sequence<std::tuple_size<typename std::decay_t<Tuple>>::value>()))
 {
-  return simgrid::xbt::bits::apply(
-      std::forward<F>(f), std::forward<Tuple>(t),
-      std::make_index_sequence<std::tuple_size<typename std::decay<Tuple>::type>::value>());
+  return simgrid::xbt::bits::apply(std::forward<F>(f), std::forward<Tuple>(t),
+                                   std::make_index_sequence<std::tuple_size<typename std::decay_t<Tuple>>::value>());
 }
 
 template<class T> class Task;
@@ -104,11 +98,8 @@ class Task<R(Args...)> {
   struct whatever {};
 
   // Union used for storage:
-  typedef typename std::aligned_union<0,
-    void*,
-    std::pair<void(*)(),void*>,
-    std::pair<void(whatever::*)(), whatever*>
-  >::type TaskUnion;
+  using TaskUnion =
+      typename std::aligned_union_t<0, void*, std::pair<void (*)(), void*>, std::pair<void (whatever::*)(), whatever*>>;
 
   // Is F suitable for small buffer optimization?
   template<class F>
@@ -122,11 +113,11 @@ class Task<R(Args...)> {
     "SBO not working for reference_wrapper");
 
   // Call (and possibly destroy) the function:
-  typedef R (*call_function)(TaskUnion&, Args...);
+  using call_function = R (*)(TaskUnion&, Args...);
   // Destroy the function (of needed):
-  typedef void (*destroy_function)(TaskUnion&);
+  using destroy_function = void (*)(TaskUnion&);
   // Move the function (otherwise memcpy):
-  typedef void (*move_function)(TaskUnion& dest, TaskUnion& src);
+  using move_function = void (*)(TaskUnion& dest, TaskUnion& src);
 
   // Vtable of functions for manipulating whatever is in the TaskUnion:
   struct TaskVtable {
@@ -145,7 +136,7 @@ class Task<R(Args...)> {
   }
 
 public:
-  Task() { /* Nothing to do */}
+  Task() = default;
   explicit Task(std::nullptr_t) { /* Nothing to do */}
   ~Task()
   {
@@ -159,7 +150,7 @@ public:
     if (that.vtable_ && that.vtable_->move)
       that.vtable_->move(buffer_, that.buffer_);
     else
-      std::memcpy(static_cast<void*>(&buffer_), static_cast<void*>(&that.buffer_), sizeof(buffer_));
+      std::memcpy(&buffer_, &that.buffer_, sizeof(buffer_));
     vtable_      = std::move(that.vtable_);
     that.vtable_ = nullptr;
   }
@@ -170,21 +161,19 @@ public:
     if (that.vtable_ && that.vtable_->move)
       that.vtable_->move(buffer_, that.buffer_);
     else
-      std::memcpy(static_cast<void*>(&buffer_), static_cast<void*>(&that.buffer_), sizeof(buffer_));
+      std::memcpy(&buffer_, &that.buffer_, sizeof(buffer_));
     vtable_      = std::move(that.vtable_);
     that.vtable_ = nullptr;
     return *this;
   }
 
 private:
-  template<class F>
-  typename std::enable_if<canSBO<F>()>::type
-  init(F code)
+  template <class F> typename std::enable_if_t<canSBO<F>()> init(F code)
   {
     const static TaskVtable vtable {
       // Call:
       [](TaskUnion& buffer, Args... args) {
-        F* src = reinterpret_cast<F*>(&buffer);
+        auto* src = reinterpret_cast<F*>(&buffer);
         F code = std::move(*src);
         src->~F();
         // NOTE: std::forward<Args>(args)... is correct.
@@ -194,13 +183,13 @@ private:
       std::is_trivially_destructible<F>::value ?
       static_cast<destroy_function>(nullptr) :
       [](TaskUnion& buffer) {
-        F* code = reinterpret_cast<F*>(&buffer);
+        auto* code = reinterpret_cast<F*>(&buffer);
         code->~F();
       },
       // Move:
       [](TaskUnion& dst, TaskUnion& src) {
-        F* src_code = reinterpret_cast<F*>(&src);
-        F* dst_code = reinterpret_cast<F*>(&dst);
+        auto* src_code = reinterpret_cast<F*>(&src);
+        auto* dst_code = reinterpret_cast<F*>(&dst);
         new(dst_code) F(std::move(*src_code));
         src_code->~F();
       }
@@ -209,7 +198,7 @@ private:
     vtable_ = &vtable;
   }
 
-  template <class F> typename std::enable_if<not canSBO<F>()>::type init(F code)
+  template <class F> typename std::enable_if_t<not canSBO<F>()> init(F code)
   {
     const static TaskVtable vtable {
       // Call:
@@ -253,7 +242,8 @@ template<class F, class... Args>
 class TaskImpl {
   F code_;
   std::tuple<Args...> args_;
-  typedef decltype(simgrid::xbt::apply(std::move(code_), std::move(args_))) result_type;
+  using result_type = decltype(simgrid::xbt::apply(std::move(code_), std::move(args_)));
+
 public:
   TaskImpl(F code, std::tuple<Args...> args) :
     code_(std::move(code)),