libs/pbd/cpus.cc

   1 /*
   2   Copyright (C) 2010 Paul Davis
   3   Author: Torben Hohn
   4
   5   This program is free software; you can redistribute it and/or modify
   6   it under the terms of the GNU General Public License as published by
   7   the Free Software Foundation; either version 2 of the License, or
   8   (at your option) any later version.
   9
  10   This program is distributed in the hope that it will be useful,
  11   but WITHOUT ANY WARRANTY; without even the implied warranty of
  12   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13   GNU General Public License for more details.
  14
  15   You should have received a copy of the GNU General Public License
  16   along with this program; if not, write to the Free Software
  17   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  18
  19 */
  20
  21 #ifdef WAF_BUILD
  22 #include "libpbd-config.h"
  23 #endif
  24
  25 #ifdef __linux__
  26 #include <unistd.h>
  27 #elif defined(__APPLE__) || defined(__FreeBSD__)
  28 #include <sys/types.h>
  29 #include <sys/sysctl.h>
  30 #endif
  31
  32 #include "pbd/cpus.h"
  33
  34 uint32_t
  35 hardware_concurrency()
  36 {
  37 #if defined(PTW32_VERSION) || defined(__hpux)
  38         return pthread_num_processors_np();
  39 #elif defined(__APPLE__) || defined(__FreeBSD__)
  40         int count;
  41         size_t size=sizeof(count);
  42         return sysctlbyname("hw.ncpu",&count,&size,NULL,0)?0:count;
  43 #elif defined(HAVE_UNISTD) && defined(_SC_NPROCESSORS_ONLN)
  44         int const count=sysconf(_SC_NPROCESSORS_ONLN);
  45         return (count>0)?count:0;
  46 #else
  47         return 0;
  48 #endif
  49 }