Make getting the getting number of CPU cores more portable

Source/wtf/NumberOfCores.cpp

 /*
  * Copyright (C) 2012 University of Szeged. All rights reserved.
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  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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 #include "config.h"
 #include "NumberOfCores.h"
 
-#if OS(MACOSX) || OS(OPENBSD) || OS(FREEBSD)
-#include <sys/param.h>
-// sys/types.h must come before sys/sysctl.h because the latter uses
-// data types defined in the former. See sysctl(3) and style(9).
-#include <sys/types.h>
-#include <sys/sysctl.h>
-#elif OS(LINUX)
-#include <unistd.h>
-#elif OS(WIN)
+#if OS(WIN)
 #include "wtf/UnusedParam.h"
 #include <windows.h>
+#else
+#include <unistd.h>
 #endif
 
 namespace WTF {
 
 int numberOfProcessorCores()
 {
     const int defaultIfUnavailable = 1;
     static int s_numberOfCores = -1;
 
     if (s_numberOfCores > 0)
         return s_numberOfCores;
 
-#if OS(MACOSX) || OS(OPENBSD) || OS(NETBSD) || OS(FREEBSD)
-    unsigned result;
-    size_t length = sizeof(result);
-    int name[] = {
-            CTL_HW,
-            HW_NCPU
-    };
-    int sysctlResult = sysctl(name, sizeof(name) / sizeof(int), &result, &length, 0, 0);
-
-    s_numberOfCores = sysctlResult < 0 ? defaultIfUnavailable : result;
-#elif OS(LINUX)
-    long sysconfResult = sysconf(_SC_NPROCESSORS_ONLN);
-
-    s_numberOfCores = sysconfResult < 0 ? defaultIfUnavailable : static_cast<int>(sysconfResult);
+#if OS(ANDROID)
+    // FIXME: Can we do better on Android - perhaps calling sysconf() ?

[Nico, 2013/09/12 19:34:55]

luckily we have 20 different implementations of everything in our codebase, so
it's easy to compare notes.

webrtc also does the sysconf call for android:
https://code.google.com/p/chromium/codesearch#chromium/src/third_party/webrtc...

v8 always calls sysconf on non-windows, but not sure if that's intentional on
android:
https://code.google.com/p/chromium/codesearch#chromium/src/v8/src/cpu.cc&ct=r...

same for nacl:
https://code.google.com/p/chromium/codesearch#chromium/src/chrome/test/nacl/n...

vp8 does a poor job on non-win:
https://code.google.com/p/chromium/codesearch#chromium/src/third_party/libvpx...
(but supports os2 :-D)

So I guess I'd remove the OS(ANDROID).

+    s_numberOfCores = defaultIfUnavailable;
 #elif OS(WIN)
     UNUSED_PARAM(defaultIfUnavailable);
     SYSTEM_INFO sysInfo;
     GetSystemInfo(&sysInfo);
 
     s_numberOfCores = sysInfo.dwNumberOfProcessors;
 #else
-    s_numberOfCores = defaultIfUnavailable;
+    long sysconfResult = sysconf(_SC_NPROCESSORS_ONLN);
+
+    s_numberOfCores = sysconfResult < 0 ? defaultIfUnavailable : static_cast<int>(sysconfResult);
 #endif
     return s_numberOfCores;
 }
 
 }