From a416ab17ecf9f2cb0f1e3f7bd645a8d1ce690ca2 Mon Sep 17 00:00:00 2001
From: rpj <rpj>
Date: Mon, 18 Feb 2002 03:16:52 +0000
Subject: Major reorganisation of source code; new routine and tests added.

---
 ptw32_getprocessors.c | 84 +++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 84 insertions(+)
 create mode 100644 ptw32_getprocessors.c

(limited to 'ptw32_getprocessors.c')

diff --git a/ptw32_getprocessors.c b/ptw32_getprocessors.c
new file mode 100644
index 0000000..79a7b7b
--- /dev/null
+++ b/ptw32_getprocessors.c
@@ -0,0 +1,84 @@
+/*
+ * ptw32_getprocessors.c
+ *
+ * Description:
+ * This translation unit implements routines which are private to
+ * the implementation and may be used throughout it.
+ *
+ * --------------------------------------------------------------------------
+ *
+ *      Pthreads-win32 - POSIX Threads Library for Win32
+ *      Copyright(C) 1998 John E. Bossom
+ *      Copyright(C) 1999,2002 Pthreads-win32 contributors
+ * 
+ *      Contact Email: rpj@ise.canberra.edu.au
+ * 
+ *      The current list of contributors is contained
+ *      in the file CONTRIBUTORS included with the source
+ *      code distribution. The list can also be seen at the
+ *      following World Wide Web location:
+ *      http://sources.redhat.com/pthreads-win32/contributors.html
+ * 
+ *      This library is free software; you can redistribute it and/or
+ *      modify it under the terms of the GNU Lesser General Public
+ *      License as published by the Free Software Foundation; either
+ *      version 2 of the License, or (at your option) any later version.
+ * 
+ *      This library is distributed in the hope that it will be useful,
+ *      but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *      Lesser General Public License for more details.
+ * 
+ *      You should have received a copy of the GNU Lesser General Public
+ *      License along with this library in the file COPYING.LIB;
+ *      if not, write to the Free Software Foundation, Inc.,
+ *      59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
+ */
+
+#include "pthread.h"
+#include "implement.h"
+
+
+/*
+ * ptw32_getprocessors()
+ *
+ * Get the number of CPUs available to the process.
+ *
+ * If the available number of CPUs is 1 then pthread_spin_lock()
+ * will block rather than spin if the lock is already owned.
+ *
+ * pthread_spin_init() calls this routine when initialising
+ * a spinlock. If the number of available processors changes
+ * (after a call to SetProcessAffinityMask()) then only
+ * newly initialised spinlocks will notice.
+ */
+int
+ptw32_getprocessors(int * count)
+{
+  DWORD vProcessCPUs;
+  DWORD vSystemCPUs;
+  int result = 0;
+
+  if (GetProcessAffinityMask(GetCurrentProcess(),
+			     &vProcessCPUs,
+			     &vSystemCPUs))
+    {
+      DWORD bit;
+      int CPUs = 0;
+
+      for (bit = 1; bit != 0; bit <<= 1)
+	{
+	  if (vProcessCPUs & bit)
+	    {
+	      CPUs++;
+	    }
+	}
+      *count = CPUs;
+    }
+  else
+    {
+      result = EAGAIN;
+    }
+
+  return(result);
+}
-- 
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