Add GetSystemTimes() to Kernel32

CHANGES.md

@@ -17,6 +17,7 @@ Features
 * [#535](https://github.com/java-native-access/jna/pull/535): Added `SHEmptyRecycleBin`, `ShellExecuteEx` to `com.sun.jna.platform.win32.Shell32` - [@mlfreeman2](https://github.com/mlfreeman2).
 * [#535](https://github.com/java-native-access/jna/pull/535): Added `GetDesktopWindow` to `com.sun.jna.platform.win32.User32` - [@mlfreeman2](https://github.com/mlfreeman2).
 * [#543](https://github.com/java-native-access/jna/pull/543): Added `ProcessIdToSessionId`, `LoadLibraryEx`, `FreeLibrary` and `Find/Load/Lock/SizeofResource` to `com.sun.jna.platform.win32.Kernel32` - [@mlfreeman2](https://github.com/mlfreeman2).
+* [#547](https://github.com/java-native-access/jna/pull/547): Added `GetSystemTimes` to `com.sun.jna.platform.win32.Kernel32` - [@dbwiddis](https://github.com/dbwiddis).
 
 Bug Fixes
 ---------

contrib/platform/src/com/sun/jna/platform/win32/Kernel32.java

@@ -181,6 +181,32 @@ boolean ReadFile(HANDLE hFile, byte[] lpBuffer, int nNumberOfBytesToRead,
      */
     boolean SetLocalTime(SYSTEMTIME lpSystemTime);
 
+    /**
+     * Retrieves system timing information. On a multiprocessor system, the
+     * values returned are the sum of the designated times across all
+     * processors.
+     * 
+     * @param lpIdleTime
+     *            A pointer to a {@link WinBase.FILETIME} structure that
+     *            receives the amount of time that the system has been idle.
+     * @param lpKernelTime
+     *            A pointer to a {@link WinBase.FILETIME} structure that 
+     *            receives the amount of time that the system has spent
+     *            executing in Kernel mode (including all threads in all
+     *            processes, on all processors). This time value also includes
+     *            the amount of time the system has been idle.
+     * @param lpUserTime
+     *            A pointer to a {@link WinBase.FILETIME} structure that
+     *            receives the amount of time that the system has spent
+     *            executing in User mode (including all threads in all
+     *            processes, on all processors).
+     * @return {@code true} if the function succeeds, {@code false} otherwise.
+     *         If the function fails, call {@link #GetLastError()} to get extended error
+     *         information.
+     * @see <a href="https://msdn.microsoft.com/en-us/library/windows/desktop/ms724400(v=vs.85).aspx">GetSystemTimes documentation</a>
+     */
+    boolean GetSystemTimes(WinBase.FILETIME lpIdleTime, WinBase.FILETIME lpKernelTime, WinBase.FILETIME lpUserTime);
+
     /**
      * The GetTickCount function retrieves the number of milliseconds that have
      * elapsed since the system was started, up to 49.7 days.

contrib/platform/test/com/sun/jna/platform/win32/Kernel32Test.java

@@ -384,6 +384,22 @@ public void testGetSystemInfo() {
         assertTrue(lpSystemInfo.dwNumberOfProcessors.intValue() > 0);
     }
 
+    public void testGetSystemTimes() {
+      Kernel32 kernel = Kernel32.INSTANCE;
+      WinBase.FILETIME lpIdleTime = new WinBase.FILETIME();
+      WinBase.FILETIME lpKernelTime = new WinBase.FILETIME();
+      WinBase.FILETIME lpUserTime = new WinBase.FILETIME();
+      boolean succ = kernel.GetSystemTimes(lpIdleTime, lpKernelTime, lpUserTime);
+      assertTrue(succ);
+      long idleTime = WinBase.FILETIME.dateToFileTime(lpIdleTime.toDate());
+      long kernelTime = WinBase.FILETIME.dateToFileTime(lpKernelTime.toDate());
+      long userTime = WinBase.FILETIME.dateToFileTime(lpUserTime.toDate());
+      // All should be >= 0.  kernel includes idle.
+      assertTrue(idle >= 0);
+      assertTrue(kernel >= idle);
+      assertTrue(user >= 0);
+    }
+
     public void testIsWow64Process() {
         try {
             IntByReference isWow64 = new IntByReference(42);