From 5aff6c228baf2aa3c4f0b82b34d1389bb33c0984 Mon Sep 17 00:00:00 2001
From: Michael Wild <themiwi@users.sourceforge.net>
Date: Fri, 8 Oct 2010 09:16:04 +0200
Subject: [PATCH] ENH: Added module ProcessorCount.cmake

Credit goes to David Cole (http://www.kitware.com/blog/home/post/63).

Signed-off-by: Michael Wild <themiwi@users.sourceforge.net>
---
 Modules/ProcessorCount.cmake |   60 ++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 60 insertions(+), 0 deletions(-)
 create mode 100644 Modules/ProcessorCount.cmake

diff --git a/Modules/ProcessorCount.cmake b/Modules/ProcessorCount.cmake
new file mode 100644
index 0000000..b6ba4f4
--- /dev/null
+++ b/Modules/ProcessorCount.cmake
@@ -0,0 +1,60 @@
+# - Determine the number of processors/cores
+#
+# Sets the variable PROCESSOR_COUNT to the number of physical cores available
+# on the machine if the information can be determined. Otherwise it is set to
+# 0. Currently this functionality is only implemented for Windows, Mac OS X and
+# Unix system providing the /proc/cpuinfo interface (e.g. Linux).
+
+# A more reliable way might be to compile a small C program that uses the CPUID
+# instruction, but that again requires compiler support or compiling assembler
+# code.
+
+#=============================================================================
+# Copyright 2002-2009 Kitware, Inc.
+#
+# Distributed under the OSI-approved BSD License (the "License");
+# see accompanying file Copyright.txt for details.
+#
+# This software is distributed WITHOUT ANY WARRANTY; without even the
+# implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+# See the License for more information.
+#=============================================================================
+# (To distributed this file outside of CMake, substitute the full
+#  License text for the above reference.)
+
+if(NOT DEFINED PROCESSOR_COUNT)
+  # Unknown:
+  set(PROCESSOR_COUNT 0)
+
+  # Windows:
+  if(WIN32)
+    set(PROCESSOR_COUNT "$ENV{NUMBER_OF_PROCESSORS}")
+    return()
+  endif()
+
+  # Mac:
+  if(APPLE)
+    find_program(_pc_cmd_sysctl sysctl)
+    if(_pc_cmd_sysctl)
+      execute_process(COMMAND ${_pc_cmd_sysctl} -n hw.ncpu
+        OUTPUT_VARIABLE PROCESSOR_COUNT)
+    endif()
+    return()
+  endif()
+
+  find_program(_pc_cmd_getconf getconf)
+  if(_pc_cmd_getconf)
+    # Linux and other systems with getconf:
+    execute_process(COMMAND ${_pc_cmd_getconf} _NPROCESSORS_ONLN
+      OUTPUT_VARIABLE PROCESSOR_COUNT)
+    return()
+  else()
+    # Linux and other systems with /proc/cpuinfo:
+    set(_pc_cpuinfo_file /proc/cpuinfo)
+    if(EXISTS "${_pc_cpuinfo_file}")
+      file(STRINGS "${_pc_cpuinfo_file}" _pc_procs REGEX "^processor.: [0-9]+$")
+      list(LENGTH _pc_procs PROCESSOR_COUNT)
+      return()
+    endif()
+  endif()
+endif()
-- 
1.7.2.3