1 // 2 // difftime.cpp 3 // 4 // Copyright (c) Microsoft Corporation. All rights reserved. 5 // 6 // The difftime() family of functions, which compute the difference between time 7 // values. 8 // 9 #include <corecrt_internal_time.h> 10 11 12 13 // Computes the difference between two times (b - a). Returns a double with the 14 // difference in seconds between the two times. Returns zero if the input is 15 // invalid. 16 template <typename TimeType> 17 static double __cdecl common_difftime(TimeType const b, TimeType const a) throw() 18 { 19 _VALIDATE_RETURN_NOEXC(a >= 0 && b >= 0, EINVAL, 0); 20 21 return static_cast<double>(b - a); 22 } 23 24 extern "C" double __cdecl _difftime32(__time32_t const b, __time32_t const a) 25 { 26 return common_difftime(b, a); 27 } 28 29 extern "C" double __cdecl _difftime64(__time64_t const b, __time64_t const a) 30 { 31 return common_difftime(b, a); 32 } 33