2006-09-20 Casey Marshall <csm@gnu.org>

	* configure.ac (AC_CHECK_HEADERS): check for `sys/epoll.h.'
	(AC_CHECK_FUNCS): check for `epoll_create.'
	* gnu/java/nio/EpollSelectionKeyImpl.java: new file.
	* gnu/java/nio/EpollSelectorImpl.java: new file.
	* gnu/java/nio/SelectorProviderImpl.java (epoll_failed): new class
	field.
	(openSelector): return epoll selector if requested and available.
	* include/Makefile.am (H_FILES): add gnu_java_nio_EpollSelectorImpl.h.
	(gnu_java_nio_EpollSelectorImpl.h): new target.
	* include/gnu_java_nio_EpollSelectorImpl.h: new file.
	* native/jni/java-nio/Makefile.am (libjavanio_la_SOURCES): add
	gnu_java_nio_EpollSelectorImpl.c.
	* native/jni/java-nio/gnu_java_nio_EpollSelectorImpl.c: new file.

1 files changed, 21 insertions, 1 deletions

diff --git a/gnu/java/nio/SelectorProviderImpl.java b/gnu/java/nio/SelectorProviderImpl.java
index a9a122570..56167b69e 100644
--- a/gnu/java/nio/SelectorProviderImpl.java
+++ b/gnu/java/nio/SelectorProviderImpl.java
@@ -53,6 +53,7 @@ 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 ()
   {
@@ -76,12 +77,31 @@ public class SelectorProviderImpl extends SelectorProvider
     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))
-      throw new UnsupportedOperationException("epoll selector not yet implemented");
+      {
+        // 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);
   }