diff options
Diffstat (limited to 'src/chrono.cpp')
| -rw-r--r-- | src/chrono.cpp | 83 |
1 files changed, 65 insertions, 18 deletions
diff --git a/src/chrono.cpp b/src/chrono.cpp index 62149fbf420c..b9d6bf97be33 100644 --- a/src/chrono.cpp +++ b/src/chrono.cpp @@ -12,14 +12,23 @@ #include "system_error" // __throw_system_error #include <time.h> // clock_gettime, CLOCK_MONOTONIC and CLOCK_REALTIME +#if defined(_WIN32) +#define WIN32_LEAN_AND_MEAN +#define VC_EXTRA_LEAN +#include <Windows.h> +#if _WIN32_WINNT >= _WIN32_WINNT_WIN8 +#include <winapifamily.h> +#endif +#else #if !defined(CLOCK_REALTIME) #include <sys/time.h> // for gettimeofday and timeval #endif +#endif -#if !defined(_LIBCPP_HAS_NO_MONOTONIC_CLOCK) && !defined(CLOCK_MONOTONIC) +#if !defined(_LIBCPP_HAS_NO_MONOTONIC_CLOCK) #if __APPLE__ #include <mach/mach_time.h> // mach_absolute_time, mach_timebase_info_data_t -#else +#elif !defined(_WIN32) && !defined(CLOCK_MONOTONIC) #error "Monotonic clock not implemented" #endif #endif @@ -36,6 +45,32 @@ const bool system_clock::is_steady; system_clock::time_point system_clock::now() _NOEXCEPT { +#if defined(_WIN32) + // FILETIME is in 100ns units + using filetime_duration = + _VSTD::chrono::duration<__int64, + _VSTD::ratio_multiply<_VSTD::ratio<100, 1>, + nanoseconds::period>>; + + // The Windows epoch is Jan 1 1601, the Unix epoch Jan 1 1970. + static _LIBCPP_CONSTEXPR const filetime_duration + nt_to_unix_epoch{11644473600}; + + FILETIME ft; +#if _WIN32_WINNT >= _WIN32_WINNT_WIN8 +#if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP) + GetSystemTimePreciseAsFileTime(&ft); +#else + GetSystemTimeAsFileTime(&ft); +#endif +#else + GetSystemTimeAsFileTime(&ft); +#endif + + filetime_duration d{(static_cast<__int64>(ft.dwHighDateTime) << 32) | + static_cast<__int64>(ft.dwLowDateTime)}; + return time_point(duration_cast<duration>(d - nt_to_unix_epoch)); +#else #ifdef CLOCK_REALTIME struct timespec tp; if (0 != clock_gettime(CLOCK_REALTIME, &tp)) @@ -46,6 +81,7 @@ system_clock::now() _NOEXCEPT gettimeofday(&tv, 0); return time_point(seconds(tv.tv_sec) + microseconds(tv.tv_usec)); #endif // CLOCK_REALTIME +#endif } time_t @@ -69,18 +105,7 @@ system_clock::from_time_t(time_t t) _NOEXCEPT const bool steady_clock::is_steady; -#ifdef CLOCK_MONOTONIC - -steady_clock::time_point -steady_clock::now() _NOEXCEPT -{ - struct timespec tp; - if (0 != clock_gettime(CLOCK_MONOTONIC, &tp)) - __throw_system_error(errno, "clock_gettime(CLOCK_MONOTONIC) failed"); - return time_point(seconds(tp.tv_sec) + nanoseconds(tp.tv_nsec)); -} - -#elif defined(__APPLE__) +#if defined(__APPLE__) // mach_absolute_time() * MachInfo.numer / MachInfo.denom is the number of // nanoseconds since the computer booted up. MachInfo.numer and MachInfo.denom @@ -90,8 +115,6 @@ steady_clock::now() _NOEXCEPT // MachInfo.numer / MachInfo.denom is often 1 on the latest equipment. Specialize // for that case as an optimization. -#pragma GCC visibility push(hidden) - static steady_clock::rep steady_simplified() @@ -129,8 +152,6 @@ init_steady_clock() return &steady_full; } -#pragma GCC visibility pop - steady_clock::time_point steady_clock::now() _NOEXCEPT { @@ -138,6 +159,32 @@ steady_clock::now() _NOEXCEPT return time_point(duration(fp())); } +#elif defined(_WIN32) + +steady_clock::time_point +steady_clock::now() _NOEXCEPT +{ + static LARGE_INTEGER freq; + static BOOL initialized = FALSE; + if (!initialized) + initialized = QueryPerformanceFrequency(&freq); // always succceeds + + LARGE_INTEGER counter; + QueryPerformanceCounter(&counter); + return time_point(duration(counter.QuadPart * nano::den / freq.QuadPart)); +} + +#elif defined(CLOCK_MONOTONIC) + +steady_clock::time_point +steady_clock::now() _NOEXCEPT +{ + struct timespec tp; + if (0 != clock_gettime(CLOCK_MONOTONIC, &tp)) + __throw_system_error(errno, "clock_gettime(CLOCK_MONOTONIC) failed"); + return time_point(seconds(tp.tv_sec) + nanoseconds(tp.tv_nsec)); +} + #else #error "Monotonic clock not implemented" #endif |