45 lines
960 B
C
45 lines
960 B
C
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#pragma once
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#include "NonCopyable.h"
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#include "../os/Atomic.h"
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#include "../os/Mutex.h"
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namespace il2cpp
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{
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namespace utils
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{
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typedef void (*CallOnceFunc) (void* arg);
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struct OnceFlag : NonCopyable
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{
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OnceFlag() : m_Flag(NULL)
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{
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}
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friend void CallOnce(OnceFlag& flag, CallOnceFunc func, void* arg);
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bool IsSet()
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{
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return il2cpp::os::Atomic::ReadPointer(&m_Flag) ? true : false;
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}
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private:
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void* m_Flag;
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il2cpp::os::FastMutex m_Mutex;
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};
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inline void CallOnce(OnceFlag& flag, CallOnceFunc func, void* arg)
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{
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if (!il2cpp::os::Atomic::ReadPointer(&flag.m_Flag))
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{
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os::FastAutoLock lock(&flag.m_Mutex);
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if (!il2cpp::os::Atomic::ReadPointer(&flag.m_Flag))
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{
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func(arg);
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il2cpp::os::Atomic::ExchangePointer(&flag.m_Flag, (void*)1);
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}
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}
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}
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}
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}
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