win: clock implementation

util/misc/clock.h

 // Copyright 2014 The Crashpad Authors. All rights reserved.
 //
 // 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.
 
 #ifndef CRASHPAD_UTIL_MISC_CLOCK_H_
 #define CRASHPAD_UTIL_MISC_CLOCK_H_
 
 #include <stdint.h>
 
+#include "build/build_config.h"
+
 namespace crashpad {
 
 //! \brief Returns the value of the system’s monotonic clock.
 //!
 //! The monotonic clock is a tick counter whose epoch is unspecified. It is a
 //! monotonically-increasing clock that cannot be set, and never jumps backwards
 //! on a running system. The monotonic clock may stop while the system is
 //! sleeping, and it may be reset when the system starts up. This clock is
 //! suitable for computing durations of events. Subject to the underlying
 //! clock’s resolution, successive calls to this function will result in a
 //! series of increasing values.
 //!
 //! \return The value of the system’s monotonic clock, in nanoseconds.
 uint64_t ClockMonotonicNanoseconds();
 
+#if !defined(OS_WIN)  // Not implemented on Windows yet.
+
 //! \brief Sleeps for the specified duration.
 //!
 //! \param[in] nanoseconds The number of nanoseconds to sleep. The actual sleep
 //!     may be slightly longer due to latencies and timer resolution.
 //!
 //! This function is resilient against the underlying `nanosleep()` system call
 //! being interrupted by a signal.
 void SleepNanoseconds(uint64_t nanoseconds);
 
+#endif
+
 }  // namespace crashpad
 
 #endif  // CRASHPAD_UTIL_MISC_CLOCK_H_