1 ///////////////////////////////////////////////////////////////////////////////
2 //
3 /// \file       tuklib_cpucores.c
4 /// \brief      Get the number of CPU cores online
5 //
6 //  Author:     Lasse Collin
7 //
8 //  This file has been put into the public domain.
9 //  You can do whatever you want with this file.
10 //
11 ///////////////////////////////////////////////////////////////////////////////
12 
13 #include "tuklib_cpucores.h"
14 
15 #if defined(TUKLIB_CPUCORES_SYSCTL)
16 #	ifdef HAVE_SYS_PARAM_H
17 #		include <sys/param.h>
18 #	endif
19 #	include <sys/sysctl.h>
20 
21 #elif defined(TUKLIB_CPUCORES_SYSCONF)
22 #	include <unistd.h>
23 #endif
24 
25 
26 extern uint32_t
27 tuklib_cpucores(void)
28 {
29 	uint32_t ret = 0;
30 
31 #if defined(TUKLIB_CPUCORES_SYSCTL)
32 	int name[2] = { CTL_HW, HW_NCPU };
33 	int cpus;
34 	size_t cpus_size = sizeof(cpus);
35 	if (sysctl(name, 2, &cpus, &cpus_size, NULL, 0) != -1
36 			&& cpus_size == sizeof(cpus) && cpus > 0)
37 		ret = (uint32_t)cpus;
38 
39 #elif defined(TUKLIB_CPUCORES_SYSCONF)
40 #	ifdef _SC_NPROCESSORS_ONLN
41 	// Most systems
42 	const long cpus = sysconf(_SC_NPROCESSORS_ONLN);
43 #	else
44 	// IRIX
45 	const long cpus = sysconf(_SC_NPROC_ONLN);
46 #	endif
47 	if (cpus > 0)
48 		ret = (uint32_t)cpus;
49 #endif
50 
51 	return ret;
52 }
53