[Isolates] Enter default isolate in initializing API.

src/api.cc

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 185 matching lines @@
   FatalErrorCallback callback = GetFatalErrorHandler();
   {
     LEAVE_V8;
     callback(location, "Allocation failed - process out of memory");
   }
   // If the callback returns, we stop execution.
   UNREACHABLE();
 }
 
 
-void V8::SetFatalErrorHandler(FatalErrorCallback that) {
-  i::Isolate* isolate = i::Isolate::Current();
-  isolate->set_exception_behavior(that);
-}
-
-
 bool Utils::ReportApiFailure(const char* location, const char* message) {
   FatalErrorCallback callback = GetFatalErrorHandler();
   callback(location, message);
   i::V8::SetFatalError();
   return false;
 }
 
 
 bool V8::IsDead() {
   return i::V8::IsDead();
@@ skipping 64 matching lines @@
     if (isolate->IsInitialized()) return true;
   }
   return ApiCheck(InitializeHelper(), location, "Error initializing V8");
 }
 
 static inline bool EnsureInitialized(const char* location) {
   i::Isolate* isolate = i::Isolate::UncheckedCurrent();
   return EnsureInitializedForIsolate(isolate, location);
 }
 
+// Some initializing API functions are called early and may be
+// called on a thread different from static initializer thread.
+// If Isolate API is used, Isolate::Enter() will initialize TLS so
+// Isolate::Current() works. If it's a legacy case, then the thread
+// may not have TLS initialized yet. However, in initializing APIs it
+// may be too early to call EnsureInitialized() - some pre-init
+// parameters still have to be configured.
+static inline i::Isolate* EnterIsolateIfNeeded() {
+  i::Isolate* isolate = i::Isolate::UncheckedCurrent();
+  if (isolate != NULL)
+    return isolate;
+
+  i::Isolate::EnterDefaultIsolate();
+  isolate = i::Isolate::Current();
+  return isolate;
+}
+
+
+void V8::SetFatalErrorHandler(FatalErrorCallback that) {
+  i::Isolate* isolate = EnterIsolateIfNeeded();
+  isolate->set_exception_behavior(that);
+}
+
+
 #ifdef DEBUG
 void ImplementationUtilities::ZapHandleRange(i::Object** begin,
                                              i::Object** end) {
   i::HandleScope::ZapRange(begin, end);
 }
 #endif
 
 
 v8::Handle<v8::Primitive> ImplementationUtilities::Undefined() {
   if (!EnsureInitialized("v8::Undefined()")) return v8::Handle<v8::Primitive>();
@@ skipping 101 matching lines @@
 
 
 ResourceConstraints::ResourceConstraints()
   : max_young_space_size_(0),
     max_old_space_size_(0),
     max_executable_size_(0),
     stack_limit_(NULL) { }
 
 
 bool SetResourceConstraints(ResourceConstraints* constraints) {
-  i::Isolate* isolate = i::Isolate::Current();
+  i::Isolate* isolate = EnterIsolateIfNeeded();
 
   int young_space_size = constraints->max_young_space_size();
   int old_gen_size = constraints->max_old_space_size();
   int max_executable_size = constraints->max_executable_size();
   if (young_space_size != 0 || old_gen_size != 0 || max_executable_size != 0) {
+    // After initialization it's too late to change Heap constraints.
+    ASSERT(!isolate->IsInitialized());
     bool result = isolate->heap()->ConfigureHeap(young_space_size / 2,
                                                  old_gen_size,
                                                  max_executable_size);
     if (!result) return false;
   }
   if (constraints->stack_limit() != NULL) {
     uintptr_t limit = reinterpret_cast<uintptr_t>(constraints->stack_limit());
     isolate->stack_guard()->SetStackLimit(limit);
   }
   return true;
@@ skipping 3592 matching lines @@
   if (fits_into_int32_t) {
     return Integer::New(static_cast<int32_t>(value));
   }
   ENTER_V8;
   i::Handle<i::Object> result = FACTORY->NewNumber(value);
   return Utils::IntegerToLocal(result);
 }
 
 
 void V8::IgnoreOutOfMemoryException() {
-  i::Isolate::Current()->handle_scope_implementer()->set_ignore_out_of_memory(
+  EnterIsolateIfNeeded()->handle_scope_implementer()->set_ignore_out_of_memory(
       true);
 }
 
 
 bool V8::AddMessageListener(MessageCallback that, Handle<Value> data) {
   EnsureInitialized("v8::V8::AddMessageListener()");
   ON_BAILOUT("v8::V8::AddMessageListener()", return false);
   ENTER_V8;
   HandleScope scope;
   NeanderArray listeners(FACTORY->message_listeners());
@@ skipping 1200 matching lines @@
 
 
 char* HandleScopeImplementer::Iterate(ObjectVisitor* v, char* storage) {
   HandleScopeImplementer* thread_local =
       reinterpret_cast<HandleScopeImplementer*>(storage);
   thread_local->IterateThis(v);
   return storage + ArchiveSpacePerThread();
 }
 
 } }  // namespace v8::internal