Timer.cpp

#if defined(_WIN32)
#include <Windows.h>
#elif defined(__MACH__)
#include <time.h>
#include <mach/clock.h>
#include <mach/mach.h>
#else
#include <time.h>
#endif
#include "Core/Utils.h"

double get_time_milliseconds()
{
#if defined(_WIN32)
    static double freq = 0.0;
    if (freq == 0.0) {
        LARGE_INTEGER li;
        if (!QueryPerformanceFrequency(&li))
            die("clock failure");
        freq = (double)li.QuadPart / 1000.0;
    }
    LARGE_INTEGER li;
    QueryPerformanceCounter(&li);
    return (double)li.QuadPart / freq;
#elif defined(__MACH__)
    struct timespec t;
    clock_serv_t cclock;
    mach_timespec_t mts;
    host_get_clock_service(mach_host_self(), CALENDAR_CLOCK, &cclock);
    if (clock_get_time(cclock, &mts) != KERN_SUCCESS) {
        die("clock failure");
    }
    mach_port_deallocate(mach_task_self(), cclock);
    t.tv_sec = mts.tv_sec;
    t.tv_nsec = mts.tv_nsec;
    return (double)t.tv_sec * 1000.0 + (double)t.tv_nsec / 1000000.0;
#else
    struct timespec t;
    if (clock_gettime(CLOCK_MONOTONIC, &t) != 0)
        die("clock failure");
    return (double)t.tv_sec * 1000.0 + (double)t.tv_nsec / 1000000.0;
#endif
}