ptth/bare_minimum_crypto/cpp/time_helpers.cpp

#include "time_helpers.h"

#include <chrono>
#include <iostream>

namespace BareMinimumCrypto {
	using namespace std;
	using namespace chrono;
	
	int64_t get_seconds_since_epoch () {
		const auto utc_now = system_clock::now ();
		return duration_cast <seconds> (utc_now.time_since_epoch ()).count ();
	}
	
	// Most tests will use a virtual clock. But just as a smoke test,
	// make sure real time is realistic.

	int test_time () {
		const auto seconds_since_epoch = get_seconds_since_epoch ();
		
		const auto time_of_writing = 1610844872;
		if (seconds_since_epoch < time_of_writing) {
			cerr << "Error: Real time is in the past." << endl;
			return 1;
		}
		
		const int64_t about_100_years = (int64_t)100 * 365 * 86400;
		if (seconds_since_epoch > time_of_writing + about_100_years) {
			cerr << "Error: Real time is in the far future." << endl;
			return 1;
		}
		
		return 0;
	}
}