auto import from //depot/cupcake/@135843
diff --git a/libs/utils/SystemClock.cpp b/libs/utils/SystemClock.cpp
new file mode 100644
index 0000000..2bdc0ce
--- /dev/null
+++ b/libs/utils/SystemClock.cpp
@@ -0,0 +1,139 @@
+/*
+ * Copyright (C) 2008 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+/*
+ * System clock functions.
+ */
+
+#if HAVE_ANDROID_OS
+#include <linux/ioctl.h>
+#include <linux/rtc.h>
+#include <utils/Atomic.h>
+#include <linux/android_alarm.h>
+#endif
+
+#include <sys/time.h>
+#include <limits.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <string.h>
+
+#include <utils/SystemClock.h>
+#include <utils/Timers.h>
+
+#define LOG_TAG "SystemClock"
+#include "utils/Log.h"
+
+namespace android {
+
+/*
+ * Set the current time. This only works when running as root.
+ */
+int setCurrentTimeMillis(int64_t millis)
+{
+#if WIN32
+ // not implemented
+ return -1;
+#else
+ struct timeval tv;
+#if HAVE_ANDROID_OS
+ struct timespec ts;
+ int fd;
+ int res;
+#endif
+ int ret = 0;
+
+ if (millis <= 0 || millis / 1000LL >= INT_MAX) {
+ return -1;
+ }
+
+ tv.tv_sec = (time_t) (millis / 1000LL);
+ tv.tv_usec = (suseconds_t) ((millis % 1000LL) * 1000LL);
+
+ LOGD("Setting time of day to sec=%d\n", (int) tv.tv_sec);
+
+#if HAVE_ANDROID_OS
+ fd = open("/dev/alarm", O_RDWR);
+ if(fd < 0) {
+ LOGW("Unable to open alarm driver: %s\n", strerror(errno));
+ return -1;
+ }
+ ts.tv_sec = tv.tv_sec;
+ ts.tv_nsec = tv.tv_usec * 1000;
+ res = ioctl(fd, ANDROID_ALARM_SET_RTC, &ts);
+ if(res < 0) {
+ LOGW("Unable to set rtc to %ld: %s\n", tv.tv_sec, strerror(errno));
+ ret = -1;
+ }
+ close(fd);
+#else
+ if (settimeofday(&tv, NULL) != 0) {
+ LOGW("Unable to set clock to %d.%d: %s\n",
+ (int) tv.tv_sec, (int) tv.tv_usec, strerror(errno));
+ ret = -1;
+ }
+#endif
+
+ return ret;
+#endif // WIN32
+}
+
+/*
+ * native public static long uptimeMillis();
+ */
+int64_t uptimeMillis()
+{
+ int64_t when = systemTime(SYSTEM_TIME_MONOTONIC);
+ return (int64_t) nanoseconds_to_milliseconds(when);
+}
+
+/*
+ * native public static long elapsedRealtime();
+ */
+int64_t elapsedRealtime()
+{
+#if HAVE_ANDROID_OS
+ static int s_fd = -1;
+
+ if (s_fd == -1) {
+ int fd = open("/dev/alarm", O_RDONLY);
+ if (android_atomic_cmpxchg(-1, fd, &s_fd)) {
+ close(fd);
+ }
+ }
+
+ struct timespec ts;
+ int result = ioctl(s_fd,
+ ANDROID_ALARM_GET_TIME(ANDROID_ALARM_ELAPSED_REALTIME), &ts);
+
+ if (result == 0) {
+ int64_t when = seconds_to_nanoseconds(ts.tv_sec) + ts.tv_nsec;
+ return (int64_t) nanoseconds_to_milliseconds(when);
+ } else {
+ // XXX: there was an error, probably because the driver didn't
+ // exist ... this should return
+ // a real error, like an exception!
+ int64_t when = systemTime(SYSTEM_TIME_MONOTONIC);
+ return (int64_t) nanoseconds_to_milliseconds(when);
+ }
+#else
+ int64_t when = systemTime(SYSTEM_TIME_MONOTONIC);
+ return (int64_t) nanoseconds_to_milliseconds(when);
+#endif
+}
+
+}; // namespace android