# See the License for the specific language governing permissions and
# limitations under the License.
+import ctypes
+import sys
import time
+LIBRT = 'librt.so.1'
+CLOCK_MONOTONIC = 1
+
+class timespec(ctypes.Structure):
+ _fields_ = [
+ ('tv_sec', ctypes.c_long),
+ ('tv_nsec', ctypes.c_long),
+ ]
+
+try:
+ librt = ctypes.CDLL(LIBRT)
+ clock_gettime = librt.clock_gettime
+ clock_gettime.argtypes = [ctypes.c_int, ctypes.POINTER(timespec)]
+except:
+ # Librt shared library could not be loaded
+ librt = None
+
+def monotonic():
+ if not librt:
+ return time.time()
+
+ t = timespec()
+ if clock_gettime(CLOCK_MONOTONIC, ctypes.pointer(t)) == 0:
+ return t.tv_sec + t.tv_nsec * 1e-9
+ # Kernel does not support CLOCK_MONOTONIC
+ return time.time()
+
+# Use time.monotonic() if Python version >= 3.3
+if not hasattr(time, 'monotonic'):
+ time.monotonic = monotonic
def msec():
"""Returns the current time, as the amount of time since the epoch, in
milliseconds, as a float."""
- return time.time() * 1000.0
+ return time.monotonic() * 1000.0
def postfork():