Changeset 32000 in webkit for trunk/JavaScriptCore/wtf/ThreadSpecific.h

Timestamp:

Apr 17, 2008, 9:04:48 AM (17 years ago)

Author:

[email protected]

Message:

Reviewed by Maciej.

Thread static data destructors are not guaranteed to be called in any particular order;
turn ThreadSpecific into a phoenix-style singleton to avoid accessing freed memory when
deleted objects are interdependent (e.g. CommonIdentifiers and internal identifier tables).

No change on SunSpider.

• wtf/ThreadSpecific.h: (WTF::ThreadSpecific::Data::Data): (WTF::::get): (WTF::::set): (WTF::::destroy):

File:

• trunk/JavaScriptCore/wtf/ThreadSpecific.h (modified) (4 diffs)

trunk/JavaScriptCore/wtf/ThreadSpecific.h

@@ -54 +54 @@
 
 #if USE(PTHREADS) || PLATFORM(WIN)
+    struct Data : Noncopyable {
+        Data(T* value, ThreadSpecific<T>* owner) : value(value), owner(owner) {}
+
+        T* value;
+        ThreadSpecific<T>* owner;
+    };
+
     pthread_key_t m_key;
 #endif
@@ -74 +81 @@
 inline T* ThreadSpecific<T>::get()
 {
-    return static_cast<T*>(pthread_getspecific(m_key));
+    Data* data = static_cast<Data*>(pthread_getspecific(m_key));
+    return data ? data->value : 0;
 }
 
@@ -81 +89 @@
 {
     ASSERT(!get());
-    pthread_setspecific(m_key, ptr);
+    pthread_setspecific(m_key, new Data(ptr, this));
 }
 
@@ -87 +95 @@
 inline void ThreadSpecific<T>::destroy(void* ptr)
 {
-    delete static_cast<T*>(ptr);
+    Data* data = static_cast<Data*>(ptr);
+    pthread_setspecific(data->owner->m_key, 0);
+    delete data->value;
+    delete data;
 }