tuklib_cpucores.c

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//
//
//  Author:     Lasse Collin
//
//  This file has been put into the public domain.
//  You can do whatever you want with this file.
//
 
#include "tuklib_cpucores.h"
 
#if defined(_WIN32) || defined(__CYGWIN__)
#   ifndef _WIN32_WINNT
#       define _WIN32_WINNT 0x0500
#   endif
#   include <windows.h>
 
// glibc >= 2.9
#elif defined(TUKLIB_CPUCORES_SCHED_GETAFFINITY)
#   include <sched.h>
 
// FreeBSD
#elif defined(TUKLIB_CPUCORES_CPUSET)
#   include <sys/param.h>
#   include <sys/cpuset.h>
 
#elif defined(TUKLIB_CPUCORES_SYSCTL)
#   ifdef HAVE_SYS_PARAM_H
#       include <sys/param.h>
#   endif
#   include <sys/sysctl.h>
 
#elif defined(TUKLIB_CPUCORES_SYSCONF)
#   include <unistd.h>
 
// HP-UX
#elif defined(TUKLIB_CPUCORES_PSTAT_GETDYNAMIC)
#   include <sys/param.h>
#   include <sys/pstat.h>
#endif
 
 
extern uint32_t
tuklib_cpucores(void)
{
    uint32_t ret = 0;
 
#if defined(_WIN32) || defined(__CYGWIN__)
    SYSTEM_INFO sysinfo;
    GetSystemInfo(&sysinfo);
    ret = sysinfo.dwNumberOfProcessors;
 
#elif defined(TUKLIB_CPUCORES_SCHED_GETAFFINITY)
    cpu_set_t cpu_mask;
    if (sched_getaffinity(0, sizeof(cpu_mask), &cpu_mask) == 0)
        ret = (uint32_t)CPU_COUNT(&cpu_mask);
 
#elif defined(TUKLIB_CPUCORES_CPUSET)
    cpuset_t set;
    if (cpuset_getaffinity(CPU_LEVEL_WHICH, CPU_WHICH_PID, -1,
            sizeof(set), &set) == 0) {
#   ifdef CPU_COUNT
        ret = (uint32_t)CPU_COUNT(&set);
#   else
        for (unsigned i = 0; i < CPU_SETSIZE; ++i)
            if (CPU_ISSET(i, &set))
                ++ret;
#   endif
    }
 
#elif defined(TUKLIB_CPUCORES_SYSCTL)
    int name[2] = { CTL_HW, HW_NCPU };
    int cpus;
    size_t cpus_size = sizeof(cpus);
    if (sysctl(name, 2, &cpus, &cpus_size, NULL, 0) != -1
            && cpus_size == sizeof(cpus) && cpus > 0)
        ret = (uint32_t)cpus;
 
#elif defined(TUKLIB_CPUCORES_SYSCONF)
#   ifdef _SC_NPROCESSORS_ONLN
    // Most systems
    const long cpus = sysconf(_SC_NPROCESSORS_ONLN);
#   else
    // IRIX
    const long cpus = sysconf(_SC_NPROC_ONLN);
#   endif
    if (cpus > 0)
        ret = (uint32_t)cpus;
 
#elif defined(TUKLIB_CPUCORES_PSTAT_GETDYNAMIC)
    struct pst_dynamic pst;
    if (pstat_getdynamic(&pst, sizeof(pst), 1, 0) != -1)
        ret = (uint32_t)pst.psd_proc_cnt;
#endif
 
    return ret;
}