Do not call WaitForMultipleObjects with 0 as first parameter

Author: fedejeanne

resources/bundles/org.eclipse.core.resources/src/org/eclipse/core/internal/resources/refresh/win32/Win32Monitor.java

@@ -431,6 +431,11 @@ protected long[][] createHandleArrays() {
 			Set<Long> keys = fHandleValueToHandle.keySet();
 			int size = keys.size();
 			if (size == 0) {
+				// This is dangerous: the documentation of WaitForMultipleObjects says that the
+				// number of object handles cannot be zero and returning empty arrays will end
+				// up passing zero as the 1st parameter to WaitForMultipleObjects. Therefore one
+				// needs to make sure to check for this case when calling
+				// Win32Natives.WaitForMultipleObjects(int, ...)
 				return new long[0][0];
 			}
 			handles = new long[size];
@@ -607,6 +612,11 @@ public void unmonitor(IResource resource) {
 	 */
 	private void waitForNotification(long[] handleValues) {
 		int handleCount = handleValues.length;
+		if (handleCount == 0) {
+			// According to the documentation of WaitForMultipleObjects,
+			// nCount (the 1st parameter) cannot be zero
+			return;
+		}
 		int index = Win32Natives.WaitForMultipleObjects(handleCount, handleValues, false, WAIT_FOR_MULTIPLE_OBJECTS_TIMEOUT);
 		if (index == Win32Natives.WAIT_TIMEOUT) {
 			// nothing happened.

resources/bundles/org.eclipse.core.resources/src/org/eclipse/core/internal/resources/refresh/win32/Win32Natives.java

@@ -193,7 +193,7 @@ public static boolean FindNextChangeNotification(long hChangeHandle) {
 	 *   <li>All of the objects are signaled, when bWaitAll is <code>true</code></li>
 	 *   <li>The timeout interval of dwMilliseconds elapses.</li>
 	 * </ul>
-	 * @param nCount The number of handles, cannot be greater than MAXIMUM_WAIT_OBJECTS.
+	 * @param nCount The number of handles, cannot be zero and cannot be greater than MAXIMUM_WAIT_OBJECTS.
 	 * @param lpHandles The array of handles to objects to be waited upon cannot contain
 	 * duplicate handles.
 	 * @param bWaitAll If <code>true</code> requires all objects to be signaled before this