Re: One-time initialization of statics in a multithreaded world

From:

"Alex Blekhman" <tkfx.REMOVE@yahoo.com>

Newsgroups:

microsoft.public.vc.language

Date:

Fri, 20 Jul 2007 17:51:29 +0300

Message-ID:

<e7ZN21tyHHA.3564@TK2MSFTNGP04.phx.gbl>

"Bertrand Augereau" wrote:

I cooked a macro for initializing objects once in our
project, could
you review and criticize it, please?
I'm mostly interested in correctness, not performance :)

I'm not sure why do you need all these tricks with static
pointers. I'd make it like this:

#define ONE_TIME_INITIALIZE(TYPE, NAME, INITIALIZER) \
                                                        \
    static volatile LONG NAME##lock = 0L; \
                                                        \
    while(InterlockedExchange(&NAME##lock, 1) != 0) \
    { \
        Sleep(1); \
    } \
                                                        \
    static TYPE* NAME##Ptr = NULL; \
                                                        \
    if(!NAME##Ptr) \
    { \
        *NAME##Ptr = &INITIALIZER; \
    } \
                                                        \
    TYPE& NAME = *(NAME##Ptr); \
                                                        \
    InterlockedExchange(&NAME##lock, 0);

Alex