X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=folly%2FSingleton.cpp;h=7114d53de9df1ca16c630913636a4dc6436e1ddf;hb=d389a33028d1a8a8520bc5c85dbcf767131fd51c;hp=6a240181cedf13abedb9ad8ab18bf59fdf42af02;hpb=ee43735cc06a4243e6676b332035927715643be7;p=folly.git

diff --git a/folly/Singleton.cpp b/folly/Singleton.cpp
index 6a240181..7114d53d 100644
--- a/folly/Singleton.cpp
+++ b/folly/Singleton.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright 2016 Facebook, Inc.
+ * Copyright 2017 Facebook, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -16,6 +16,10 @@
 
 #include <folly/Singleton.h>
 
+#ifndef _WIN32
+#include <dlfcn.h>
+#endif
+
 #include <atomic>
 #include <cstdio>
 #include <cstdlib>
@@ -24,8 +28,26 @@
 
 #include <folly/ScopeGuard.h>
 
+#if !defined(_WIN32) && !defined(__APPLE__) && !defined(__ANDROID__)
+static void hs_init_weak(int* argc, char** argv[])
+    __attribute__((__weakref__("hs_init")));
+#endif
+
 namespace folly {
 
+SingletonVault::Type SingletonVault::defaultVaultType() {
+#if !defined(_WIN32) && !defined(__APPLE__) && !defined(__ANDROID__)
+  bool isPython = dlsym(RTLD_DEFAULT, "Py_Main");
+  bool isHaskel = &::hs_init_weak || dlsym(RTLD_DEFAULT, "hs_init");
+  bool isJVM = dlsym(RTLD_DEFAULT, "JNI_GetCreatedJavaVMs");
+  bool isD = dlsym(RTLD_DEFAULT, "_d_run_main");
+
+  return isPython || isHaskel || isJVM || isD ? Type::Relaxed : Type::Strict;
+#else
+  return Type::Relaxed;
+#endif
+}
+
 namespace detail {
 
 [[noreturn]] void singletonWarnDoubleRegistrationAndAbort(
@@ -38,7 +60,7 @@ namespace detail {
             << type.name() << ">\n";
   std::abort();
 }
-}
+} // namespace detail
 
 namespace {
 
@@ -66,7 +88,7 @@ FatalHelper fatalHelper;
 FatalHelper __attribute__ ((__init_priority__ (101))) fatalHelper;
 #endif
 
-}
+} // namespace
 
 SingletonVault::~SingletonVault() { destroyInstances(); }
 
@@ -244,4 +266,4 @@ void SingletonVault::scheduleDestroyInstances() {
   static SingletonVaultDestructor singletonVaultDestructor;
 }
 
-}
+} // namespace folly