c++ - Loki's SetLongevity function seems unsafe to me, is that so? -

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there global variable called "ptrackerarray", used in loki's setlongevity function.

declaration of ptrackerarray:

typedef std::list<lifetimetracker*> trackerarray; extern loki_export trackerarray* ptrackerarray;

definition of setlongevity:

template <typename t, typename destroyer> void setlongevity(t* pdynobject, unsigned int longevity, destroyer d) {     using namespace private;      // manage lifetime of stack manually     if(ptrackerarray==0)         ptrackerarray = new trackerarray;      // simplicity, rest of code omitted     ... }

is thread safe use ptrackerarray such in setlongevity?

as shown, not. however, if reading rest of file correctly, setlongevity is, ultimately, ever called within function wrapped in mutex [provided requested singleton thread-safe, obviously]. so while particular function has issues, use still safe.

however, mutex create in base function paramaterized on type of singleton creating, while global pointer shared between singletons. yes, appear though 2 different singleton objects in 2 different threads both access function @ once, causing havok.


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