From: Martin Quinson <martin.quinson@ens-rennes.fr>
Date: Wed, 14 Aug 2019 00:03:56 +0000 (+0200)
Subject: now, kernel::actor::simcall_blocking can return a value
X-Git-Tag: v3.24~186
X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/commitdiff_plain/5b576eb1c0ab1acba1ceb0808b3708efe8a26dc1?ds=sidebyside

now, kernel::actor::simcall_blocking can return a value
---

diff --git a/include/simgrid/simix.hpp b/include/simgrid/simix.hpp
index 473bb3f4b1..9539451154 100644
--- a/include/simgrid/simix.hpp
+++ b/include/simgrid/simix.hpp
@@ -63,6 +63,9 @@ template <class F> typename std::result_of<F()>::type simcall(F&& code, mc::Simc
  * This is very similar to simcall() right above, but the calling actor will not get rescheduled until
  * actor->simcall_answer() is called explicitely.
  *
+ * Since the return value does not come from the lambda directly, its type cannot be guessed automatically and must
+ * be provided as template parameter.
+ *
  * This is meant for blocking actions. For example, locking a mutex is a blocking simcall.
  * First it's a simcall because that's obviously a modification of the world. Then, that's a blocking simcall because if
  * the mutex happens not to be free, the actor is added to a queue of actors in the mutex. Every mutex->unlock() takes
@@ -72,7 +75,7 @@ template <class F> typename std::result_of<F()>::type simcall(F&& code, mc::Simc
  *
  * If your code never calls actor->simcall_answer() itself, the actor will never return from its simcall.
  */
-template <class F> typename std::result_of<F()>::type simcall_blocking(F&& code, mc::SimcallInspector* t = nullptr)
+template <class R, class F> R simcall_blocking(F&& code, mc::SimcallInspector* t = nullptr)
 {
   // If we are in the maestro, we take the fast path and execute the
   // code directly without simcall mashalling/unmarshalling/dispatch:
@@ -82,7 +85,6 @@ template <class F> typename std::result_of<F()>::type simcall_blocking(F&& code,
   // If we are in the application, pass the code to the maestro which
   // executes it for us and reports the result. We use a std::future which
   // conveniently handles the success/failure value for us.
-  typedef typename std::result_of<F()>::type R;
   simgrid::xbt::Result<R> result;
   simcall_run_blocking([&result, &code] { simgrid::xbt::fulfill_promise(result, std::forward<F>(code)); }, t);
   return result.get();
diff --git a/src/s4u/s4u_Actor.cpp b/src/s4u/s4u_Actor.cpp
index 1840dfe657..9cfe9fa62d 100644
--- a/src/s4u/s4u_Actor.cpp
+++ b/src/s4u/s4u_Actor.cpp
@@ -97,7 +97,7 @@ void Actor::join(double timeout)
 {
   auto issuer = SIMIX_process_self();
   auto target = pimpl_;
-  kernel::actor::simcall_blocking([issuer, target, timeout] {
+  kernel::actor::simcall_blocking<void>([issuer, target, timeout] {
     if (target->finished_) {
       // The joined process is already finished, just wake up the issuer right away
       issuer->simcall_answer();
@@ -189,7 +189,7 @@ void Actor::suspend()
   auto issuer = SIMIX_process_self();
   auto target = pimpl_;
   s4u::Actor::on_suspend(*this);
-  kernel::actor::simcall_blocking([issuer, target]() {
+  kernel::actor::simcall_blocking<void>([issuer, target]() {
     target->suspend(issuer);
     if (target != issuer) {
       /* If we are suspending ourselves, then just do not finish the simcall now */
@@ -307,7 +307,7 @@ void sleep_for(double duration)
     kernel::actor::ActorImpl* issuer = SIMIX_process_self();
     Actor::on_sleep(*issuer->ciface());
 
-    kernel::actor::simcall_blocking([issuer, duration]() {
+    kernel::actor::simcall_blocking<void>([issuer, duration]() {
       if (MC_is_active() || MC_record_replay_is_active()) {
         MC_process_clock_add(issuer, duration);
         issuer->simcall_answer();