Add initEventLoop(), processEvent(), runEventLoop() and stopEventLoop()
static methods to the Library class.
Signed-off-by: Claudio Bley <cbley@xxxxxxxxxx>
---
src/main/java/org/libvirt/Library.java | 91 ++++++++++++++++++++++++++++
src/main/java/org/libvirt/jna/Libvirt.java | 4 ++
2 files changed, 95 insertions(+)
diff --git a/src/main/java/org/libvirt/Library.java b/src/main/java/org/libvirt/Library.java
index 95c13cb..3cfb8fd 100644
--- a/src/main/java/org/libvirt/Library.java
+++ b/src/main/java/org/libvirt/Library.java
@@ -7,6 +7,8 @@ import com.sun.jna.Native;
import com.sun.jna.Pointer;
import com.sun.jna.ptr.PointerByReference;
+import java.util.concurrent.atomic.AtomicBoolean;
+
/**
* This class represents an instance of the JNA mapped libvirt
* library.
@@ -17,6 +19,8 @@ import com.sun.jna.ptr.PointerByReference;
* implementing the public API.
*/
final class Library {
+ private static AtomicBoolean runLoop = new AtomicBoolean();
+
final static Libvirt libvirt;
// an empty string array constant
@@ -85,4 +89,91 @@ final class Library {
}
}
}
+
+ /**
+ * Initialize the event loop.
+ *
+ * Registers a default event loop implementation based on the
+ * poll() system call.
+ * <p>
+ * Once registered, the application has to invoke
+ * {@link #processEvent} in a loop or call {@link #runEventLoop}
+ * in another thread.
+ * <p>
+ * Note: You must call this function <em>before</em> connecting to
+ * the hypervisor.
+ *
+ * @throws LibvirtException on failure
+ *
+ * @see #processEvent
+ * @see #runLoop
+ */
+ public static void initEventLoop() throws LibvirtException {
+ processError(libvirt.virEventRegisterDefaultImpl());
+ }
+
+ /**
+ * Run one iteration of the event loop.
+ * <p>
+ * Applications will generally want to have a thread which invokes
+ * this method in an infinite loop:
+ * <pre>
+ * {@code while (true) connection.processEvent(); }
+ * </pre>
+ * <p>
+ * Failure to do so may result in connections being closed
+ * unexpectedly as a result of keepalive timeout.
+ *
+ * @throws LibvirtException on failure
+ *
+ * @see #initEventLoop()
+ */
+ public static void processEvent() throws LibvirtException {
+ processError(libvirt.virEventRunDefaultImpl());
+ }
+
+ /**
+ * Runs the event loop.
+ *
+ * This method blocks until {@link #stopEventLoop} is called or an
+ * exception is thrown.
+ * <p>
+ * Usually, this method is run in another thread.
+ *
+ * @throws LibvirtException if there was an error during the call of a
+ * native libvirt function
+ * @throws InterruptedException if this thread was interrupted by a call to
+ * {@link java.lang.Thread#interrupt() Thread.interrupt()}
+ */
+ public static void runEventLoop() throws LibvirtException, InterruptedException {
+ runLoop.set(true);
+ do {
+ processEvent();
+ if (Thread.interrupted())
+ throw new InterruptedException();
+ } while (runLoop.get());
+ }
+
+ /**
+ * Stops the event loop.
+ *
+ * This methods stops an event loop when an event loop is
+ * currently running, otherwise it does nothing.
+ *
+ * @see #runEventLoop
+ */
+ public static void stopEventLoop() throws LibvirtException {
+ if (runLoop.getAndSet(false)) {
+ // add a timeout which fires immediately so that the processEvent
+ // method returns if it is waiting
+ libvirt.virEventAddTimeout(0, new org.libvirt.jna.Libvirt.VirEventTimeoutCallback() {
+ @Override
+ public void tick(int id, Pointer p) {
+ // remove itself right after it served its purpose
+ libvirt.virEventRemoveTimeout(id);
+ }
+ },
+ null, null);
+ }
+ }
}
diff --git a/src/main/java/org/libvirt/jna/Libvirt.java b/src/main/java/org/libvirt/jna/Libvirt.java
index 2bc5b6b..ed52bd3 100644
--- a/src/main/java/org/libvirt/jna/Libvirt.java
+++ b/src/main/java/org/libvirt/jna/Libvirt.java
@@ -187,6 +187,10 @@ public interface Libvirt extends Library {
void virResetLastError();
void virSetErrorFunc(Pointer userData, VirErrorCallback callback);
+ // Event loop functions.
+ int virEventRegisterDefaultImpl();
+ int virEventRunDefaultImpl();
+
// Domain functions
int virDomainAbortJob(DomainPointer virDomainPtr);
int virDomainAttachDevice(DomainPointer virDomainPtr, String deviceXML);
--
1.7.9.5
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