C++ 固定时间定时执行逻辑 - 二分定点法

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//C++ 11
#include <chrono>
#include <thread>


{
	//时区 - cst时间戳是从1970-01-01 08:00:00开始计时
	static const uint32_t nTimestampZone = 8 * 60 * 60;

    //一整天所需要的秒数
	static const uint64_t nWholeDaySec = 24 * 60 * 60;

	//偏差范围 - 目标12:00:00 -> 实际允许 12:00:00 ~ 12:00:20
	static const uint32_t nDeviationAreaSec = 20;

    //目标时间
	static const uint8_t nDstHour = 0;
	static const uint8_t nDstMinute = 0;
	static const uint8_t nDstSec = 0;
	static const uint32_t nDstTimestampSec = (nDstHour * 60 * 60) + (nDstMinute * 60) + (nDstSec);

	//今日是否已经执行过
	bool bExecuted = false;

    	uint64_t nTime = 0;

	while (true)
	{
#ifdef __cplusplus > 201103L	//C++11
		//此处使用C++ 11(顺带了解C++11) - 可根据自己环境更改时间方法n
		//获取系统时间 + 8:00:00 ; 因为cst时间戳是从1970-01-01 08:00:00开始计时的
		//可以查找方法将 CST时间戳自动转换成UTC时间戳 但我没找到方法，因此只能写死的8:00:00
		nTime = std::chrono::system_clock::to_time_t(std::chrono::system_clock::now()) + nTimestampZone;
#else
		//C语言中的time
		nTime = time(nullptr) + nTimestampZone;
		//std::localtime(&nTimet);
#endif
		
		//实际偏差
		int32_t nDeviation = nTime % nWholeDaySec - nDstTimestampSec;

		//偏差在一定范围内
		if (!bExecuted && nDeviation <= nDeviationAreaSec  && nDeviation >= 0)
		{

			//执行相应处理
			bExecuted = true;
			
			/**
			*
			* * do something
			* 
			**/

			printf("Executen for Current Time [%02d:%02d:%02d]nn", nTime / 60 / 60, nTime / 60 % 60, nTime % 60);

			continue;
		}
		else if (bExecuted && nDeviation <= nDeviationAreaSec && nDeviation >= 0)
		{
			//仍在区间范围内 则直接跳过
			std::this_thread::sleep_for(std::chrono::seconds(1));
			
			printf("Sleep Once in the Current Area n");
			
			continue;
		}
		else if (bExecuted && (nDeviation > nDeviationAreaSec || nDeviation < 0))
		{
			//经过区间范围之外
			bExecuted = false;
			continue;
		}



		static uint32_t nNeedSleep = 0;
		nNeedSleep = (nDeviation > 0 ? nWholeDaySec - nDeviation : (abs(nDeviation))) / 2;
		if (nNeedSleep == 1)
		{
			std::this_thread::sleep_for(std::chrono::milliseconds(100));

			printf("Sleep once for [100 milliseconds]nn");

			continue;
		}

		printf("Sleep once for [%d second]nn", nNeedSleep);

		//睡眠偏差值
		std::this_thread::sleep_for(std::chrono::seconds(nNeedSleep));

	}
}