1 files changed, 37 insertions, 0 deletions
diff --git a/gnu/java/nio/SelectorProviderImpl.java b/gnu/java/nio/SelectorProviderImpl.java
index 47521107e..56167b69e 100644
--- a/gnu/java/nio/SelectorProviderImpl.java
+++ b/gnu/java/nio/SelectorProviderImpl.java
@@ -37,6 +37,9 @@ exception statement from your version. */
 
 package gnu.java.nio;
 
+
+import gnu.classpath.SystemProperties;
+
 import java.io.IOException;
 import java.nio.channels.DatagramChannel;
 import java.nio.channels.Pipe;
@@ -47,6 +50,11 @@ import java.nio.channels.spi.SelectorProvider;
 
 public class SelectorProviderImpl extends SelectorProvider
 {
+  private static final String SELECTOR_IMPL_KQUEUE = "kqueue";
+  private static final String SELECTOR_IMPL_EPOLL = "epoll";
+  private static final String SELECTOR_IMPL = "gnu.java.nio.selectorImpl";
+  private static boolean epoll_failed = false;
+  
   public SelectorProviderImpl ()
   {
   }
@@ -66,6 +74,35 @@ public class SelectorProviderImpl extends SelectorProvider
   public AbstractSelector openSelector ()
     throws IOException
   {
+    String selectorImpl = "default";
+    if (KqueueSelectorImpl.kqueue_supported())
+      selectorImpl = SELECTOR_IMPL_KQUEUE;
+    if (EpollSelectorImpl.epoll_supported() && !epoll_failed)
+      selectorImpl = SELECTOR_IMPL_EPOLL;
+    selectorImpl = SystemProperties.getProperty(SELECTOR_IMPL, selectorImpl);
+
+    if (selectorImpl.equals(SELECTOR_IMPL_KQUEUE))
+      return new KqueueSelectorImpl(this);
+
+    if (selectorImpl.equals(SELECTOR_IMPL_EPOLL))
+      {
+        // We jump through these hoops because even though epoll may look
+        // like it's available (sys/epoll.h exists, and you can link against
+        // all the epoll functions) it may not be available in the kernel
+        // (especially 2.4 kernels), meaning you will get ENOSYS at run time.
+        //
+        // Madness!
+        try
+          {
+            return new EpollSelectorImpl(this);
+          }
+        catch (InternalError e)
+          {
+            // epoll_create throws this on ENOSYS.
+            epoll_failed = true;
+          }
+      }
+
     return new SelectorImpl (this);
   }