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31 #ifndef ThreadIdentifierDataPthreads_h
32 #define ThreadIdentifierDataPthreads_h
34 #include "wtf/Noncopyable.h"
35 #include "wtf/Threading.h"
40 // Holds ThreadIdentifier in the thread-specific storage and employs pthreads-specific 2-pass destruction to reliably remove
41 // ThreadIdentifier from threadMap. It assumes regular ThreadSpecific types don't use multiple-pass destruction.
42 class ThreadIdentifierData {
43 WTF_MAKE_NONCOPYABLE(ThreadIdentifierData);
45 ~ThreadIdentifierData();
47 // One time initialization for this class as a whole.
48 // This method must be called before initialize() and it is not thread-safe.
49 static void initializeOnce();
51 // Creates and puts an instance of ThreadIdentifierData into thread-specific storage.
52 static void initialize(ThreadIdentifier identifier);
54 // Returns 0 if thread-specific storage was not initialized.
55 static ThreadIdentifier identifier();
58 ThreadIdentifierData(ThreadIdentifier identifier)
59 : m_identifier(identifier)
60 , m_isDestroyedOnce(false)
64 // This thread-specific destructor is called 2 times when thread terminates:
65 // - first, when all the other thread-specific destructors are called, it simply remembers it was 'destroyed once'
66 // and re-sets itself into the thread-specific slot to make Pthreads to call it again later.
67 // - second, after all thread-specific destructors were invoked, it gets called again - this time, we remove the
68 // ThreadIdentifier from the threadMap, completing the cleanup.
69 static void destruct(void* data);
71 ThreadIdentifier m_identifier;
72 bool m_isDestroyedOnce;
73 static pthread_key_t m_key;
78 #endif // ThreadIdentifierDataPthreads_h