1 files changed, 94 insertions, 0 deletions
diff --git a/src/base/ThreadHelper.cpp b/src/base/ThreadHelper.cpp
new file mode 100644
index 0000000..105e116
--- /dev/null
+++ b/src/base/ThreadHelper.cpp
@@ -0,0 +1,94 @@
+//
+//  libavg - Media Playback Engine.
+//  Copyright (C) 2003-2014 Ulrich von Zadow
+//
+//  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; if not, write to the Free Software
+//  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+//
+//  Current versions can be found at www.libavg.de
+//
+
+#include "ThreadHelper.h"
+#include "OSHelper.h"
+
+#ifdef _WIN32
+#include <Windows.h>
+#endif
+
+namespace avg {
+
+void setAffinityMask(bool bIsMainThread)
+{
+    // The main thread gets the first processor to itself. All other threads share the
+    // rest of the processors available, unless, of course, there is only one processor
+    // in the machine.
+#ifdef linux
+    static cpu_set_t allProcessors;
+    static bool bInitialized = false;
+    if (!bInitialized) {
+        int rc = sched_getaffinity(0, sizeof(allProcessors), &allProcessors);
+        AVG_ASSERT(rc == 0);
+//        cerr << "All processors: ";
+//        printAffinityMask(allProcessors);
+        bInitialized = true;
+    }
+    cpu_set_t mask;
+    if (bIsMainThread) {
+        CPU_ZERO(&mask);
+        CPU_SET(0, &mask);
+//        cerr << "Main Thread: ";
+    } else {
+        mask = allProcessors;
+        if (CPU_COUNT(&mask) > 1) {
+            CPU_CLR(0, &mask);
+        }
+//        cerr << "Aux Thread: ";
+    }
+//    printAffinityMask(mask);
+    int rc = sched_setaffinity(0, sizeof(mask), &mask);
+    AVG_ASSERT(rc == 0);
+#elif defined _WIN32
+    DWORD processAffinityMask;
+    DWORD systemAffinityMask;
+    BOOL rc = GetProcessAffinityMask(GetCurrentProcess(), &processAffinityMask,
+            &systemAffinityMask);
+    AVG_ASSERT(rc == TRUE);
+    DWORD mainThreadMask = 1 << getLowestBitSet(processAffinityMask);
+    DWORD mask;
+    if (bIsMainThread) {
+        mask = mainThreadMask;
+    } else {
+        mask = processAffinityMask & ~mainThreadMask;
+        if (mask == 0) {
+            mask = processAffinityMask;
+        }
+    }
+    DWORD_PTR pPrevMask = SetThreadAffinityMask(GetCurrentThread(), mask);
+    AVG_ASSERT_MSG(pPrevMask != 0, getWinErrMsg(GetLastError()).c_str());
+#endif
+}
+
+unsigned getLowestBitSet(unsigned val)
+{
+    AVG_ASSERT(val != 0); // Doh
+
+    unsigned pos = 0;
+    while (!(val & 1)) {
+        val >>= 1;
+        ++pos;
+    }
+    return pos;
+}
+
+}