Removed dead IsSomeVector
[folly.git] / folly / Singleton-inl.h
index 2656084e81bae8abedb032d2b54ddacd815c388e..745147f0454934097e0d7332d6f6ce76c822500a 100644 (file)
@@ -69,7 +69,9 @@ void SingletonHolder<T>::registerSingletonMock(CreateFunc c, TeardownFunc t) {
     LOG(FATAL) << "Registering mock before singleton was registered: "
                << type().name();
   }
-  destroyInstance();
+  if (state_ == SingletonHolderState::Living) {
+    destroyInstance();
+  }
 
   {
     auto creationOrder = vault_.creationOrder_.wlock();
@@ -153,14 +155,18 @@ void SingletonHolder<T>::destroyInstance() {
   instance_copy_.reset();
   if (destroy_baton_) {
     constexpr std::chrono::seconds kDestroyWaitTime{5};
-    auto wait_result = destroy_baton_->timed_wait(
-      std::chrono::steady_clock::now() + kDestroyWaitTime);
-    if (!wait_result) {
+    auto last_reference_released = destroy_baton_->timed_wait(
+        std::chrono::steady_clock::now() + kDestroyWaitTime);
+    if (last_reference_released) {
+      teardown_(instance_ptr_);
+    } else {
       print_destructor_stack_trace_->store(true);
       LOG(ERROR) << "Singleton of type " << type().name() << " has a "
                  << "living reference at destroyInstances time; beware! Raw "
                  << "pointer is " << instance_ptr_ << ". It is very likely "
                  << "that some other singleton is holding a shared_ptr to it. "
+                 << "This singleton will be leaked (even if a shared_ptr to it "
+                 << "is eventually released)."
                  << "Make sure dependencies between these singletons are "
                  << "properly defined.";
     }
@@ -224,6 +230,21 @@ void SingletonHolder<T>::createInstance() {
   creating_thread_.store(std::this_thread::get_id(), std::memory_order_release);
 
   auto state = vault_.state_.rlock();
+  if (vault_.type_ != SingletonVault::Type::Relaxed &&
+      !state->registrationComplete) {
+    auto stack_trace_getter = SingletonVault::stackTraceGetter().load();
+    auto stack_trace = stack_trace_getter ? stack_trace_getter() : "";
+    if (!stack_trace.empty()) {
+      stack_trace = "Stack trace:\n" + stack_trace;
+    }
+
+    LOG(FATAL) << "Singleton " << type().name() << " requested before "
+               << "registrationComplete() call.\n"
+               << "This usually means that either main() never called "
+               << "folly::init, or singleton was requested before main() "
+               << "(which is not allowed).\n"
+               << stack_trace;
+  }
   if (state->state == SingletonVault::SingletonVaultState::Quiescing) {
     return;
   }
@@ -231,30 +252,28 @@ void SingletonHolder<T>::createInstance() {
   auto destroy_baton = std::make_shared<folly::Baton<>>();
   auto print_destructor_stack_trace =
     std::make_shared<std::atomic<bool>>(false);
-  auto teardown = teardown_;
 
   // Can't use make_shared -- no support for a custom deleter, sadly.
   std::shared_ptr<T> instance(
-    create_(),
-    [destroy_baton, print_destructor_stack_trace, teardown, type = type()]
-    (T* instance_ptr) mutable {
-      teardown(instance_ptr);
-      destroy_baton->post();
-      if (print_destructor_stack_trace->load()) {
-        std::string output = "Singleton " + type.name() + " was destroyed.\n";
-
-        auto stack_trace_getter = SingletonVault::stackTraceGetter().load();
-        auto stack_trace = stack_trace_getter ? stack_trace_getter() : "";
-        if (stack_trace.empty()) {
-          output += "Failed to get destructor stack trace.";
-        } else {
-          output += "Destructor stack trace:\n";
-          output += stack_trace;
+      create_(),
+      [ destroy_baton, print_destructor_stack_trace, type = type() ](
+          T*) mutable {
+        destroy_baton->post();
+        if (print_destructor_stack_trace->load()) {
+          std::string output = "Singleton " + type.name() + " was released.\n";
+
+          auto stack_trace_getter = SingletonVault::stackTraceGetter().load();
+          auto stack_trace = stack_trace_getter ? stack_trace_getter() : "";
+          if (stack_trace.empty()) {
+            output += "Failed to get release stack trace.";
+          } else {
+            output += "Release stack trace:\n";
+            output += stack_trace;
+          }
+
+          LOG(ERROR) << output;
         }
-
-        LOG(ERROR) << output;
-      }
-    });
+      });
 
   // We should schedule destroyInstances() only after the singleton was
   // created. This will ensure it will be destroyed before singletons,
@@ -277,6 +296,6 @@ void SingletonHolder<T>::createInstance() {
   vault_.creationOrder_.wlock()->push_back(type());
 }
 
-}
+} // namespace detail
 
-}
+} // namespace folly