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#pragma once #include <string> #include <array> #include <cstdarg> #define BEGIN_NAMESPACE( x ) namespace x { #define END_NAMESPACE } BEGIN_NAMESPACE(XorCompileTime) constexpr auto time = __TIME__; constexpr auto seed = static_cast<int>(time[7]) + static_cast<int>(time[6]) * 10 + static_cast<int>(time[4]) * 60 + static_cast<int>(time[3]) * 600 + static_cast<int>(time[1]) * 3600 + static_cast<int>(time[0]) * 36000; // 1988, Stephen Park and Keith Miller // "Random Number Generators: Good Ones Are Hard To Find", considered as "minimal standard" // Park-Miller 31 bit pseudo-random number generator, implemented with G. Carta's optimisation: // with 32-bit math and without division template < int N > struct RandomGenerator { private: static constexpr unsigned a = 16807; // 7^5 static constexpr unsigned m = 2147483647; // 2^31 - 1 static constexpr unsigned s = RandomGenerator< N - 1 >::value; static constexpr unsigned lo = a * (s & 0xFFFF); // Multiply lower 16 bits by 16807 static constexpr unsigned hi = a * (s >> 16); // Multiply higher 16 bits by 16807 static constexpr unsigned lo2 = lo + ((hi & 0x7FFF) << 16); // Combine lower 15 bits of hi with lo's upper bits static constexpr unsigned hi2 = hi >> 15; // Discard lower 15 bits of hi static constexpr unsigned lo3 = lo2 + hi; public: static constexpr unsigned max = m; static constexpr unsigned value = lo3 > m ? lo3 - m : lo3; }; template <> struct RandomGenerator< 0 > { static constexpr unsigned value = seed; }; template < int N, int M > struct RandomInt { static constexpr auto value = RandomGenerator< N + 1 >::value % M; }; template < int N > struct RandomChar { static const char value = static_cast<char>(1 + RandomInt< N, 0x7F - 1 >::value); }; template < size_t N, int K, typename Char > struct XorString { private: const char _key; std::array< Char, N + 1 > _encrypted; constexpr Char enc(Char c) const { return c ^ _key; } Char dec(Char c) const { return c ^ _key; } public: template < size_t... Is > constexpr __forceinline XorString(const Char* str, std::index_sequence< Is... >) : _key(RandomChar< K >::value), _encrypted{ enc(str[Is])... } { } __forceinline decltype(auto) decrypt(void) { for (size_t i = 0; i < N; ++i) { _encrypted[i] = dec(_encrypted[i]); } _encrypted[N] = '\0'; return _encrypted.data(); } }; //-------------------------------------------------------------------------------- //-- Note: XorStr will __NOT__ work directly with functions like printf. // To work with them you need a wrapper function that takes a const char* // as parameter and passes it to printf and alike. // // The Microsoft Compiler/Linker is not working correctly with variadic // templates! // // Use the functions below or use std::cout (and similar)! //-------------------------------------------------------------------------------- static auto w_printf = [](const char* fmt, ...) { va_list args; va_start(args, fmt); vprintf_s(fmt, args); va_end(args); }; static auto w_printf_s = [](const char* fmt, ...) { va_list args; va_start(args, fmt); vprintf_s(fmt, args); va_end(args); }; static auto w_sprintf = [](char* buf, const char* fmt, ...) { va_list args; va_start(args, fmt); vsprintf(buf, fmt, args); va_end(args); }; static auto w_sprintf_ret = [](char* buf, const char* fmt, ...) { int ret; va_list args; va_start(args, fmt); ret = vsprintf(buf, fmt, args); va_end(args); return ret; }; static auto w_sprintf_s = [](char* buf, size_t buf_size, const char* fmt, ...) { va_list args; va_start(args, fmt); vsprintf_s(buf, buf_size, fmt, args); va_end(args); }; static auto w_sprintf_s_ret = [](char* buf, size_t buf_size, const char* fmt, ...) { int ret; va_list args; va_start(args, fmt); ret = vsprintf_s(buf, buf_size, fmt, args); va_end(args); return ret; }; //Old functions before I found out about wrapper functions. //#define XorStr( s ) ( XorCompileTime::XorString< sizeof(s)/sizeof(char) - 1, __COUNTER__, char >( s, std::make_index_sequence< sizeof(s)/sizeof(char) - 1>() ).decrypt() ) //#define XorStrW( s ) ( XorCompileTime::XorString< sizeof(s)/sizeof(wchar_t) - 1, __COUNTER__, wchar_t >( s, std::make_index_sequence< sizeof(s)/sizeof(wchar_t) - 1>() ).decrypt() ) //Wrapper functions to work in all functions below #define XorStr( s ) []{ constexpr XorCompileTime::XorString< sizeof(s)/sizeof(char) - 1, __COUNTER__, char > expr( s, std::make_index_sequence< sizeof(s)/sizeof(char) - 1>() ); return expr; }().decrypt() #define XorStrW( s ) []{ constexpr XorCompileTime::XorString< sizeof(s)/sizeof(wchar_t) - 1, __COUNTER__, wchar_t > expr( s, std::make_index_sequence< sizeof(s)/sizeof(wchar_t) - 1>() ); return expr; }().decrypt() END_NAMESPACE