diff options
Diffstat (limited to 'base/time.h')
-rw-r--r-- | base/time.h | 31 |
1 files changed, 28 insertions, 3 deletions
diff --git a/base/time.h b/base/time.h index 6e9a8a4..98a711d 100644 --- a/base/time.h +++ b/base/time.h @@ -254,9 +254,27 @@ class Time { static Time FromFileTime(FILETIME ft); FILETIME ToFileTime() const; - // Enable or disable Windows high resolution timer. For more details - // see comments in time_win.cc. Returns true on success. - static bool UseHighResolutionTimer(bool use); + // The minimum time of a low resolution timer. This is basically a windows + // constant of ~15.6ms. While it does vary on some older OS versions, we'll + // treat it as static across all windows versions. + static const int kMinLowResolutionThresholdMs = 16; + + // Enable or disable Windows high resolution timer. If the high resolution + // timer is not enabled, calls to ActivateHighResolutionTimer will fail. + // When disabling the high resolution timer, this function will not cause + // the high resolution timer to be deactivated, but will prevent future + // activations. + // Must be called from the main thread. + // For more details see comments in time_win.cc. + static void EnableHighResolutionTimer(bool enable); + + // Activates or deactivates the high resolution timer based on the |activate| + // flag. If the HighResolutionTimer is not Enabled (see + // EnableHighResolutionTimer), this function will return false. Otherwise + // returns true. + // All callers to activate the high resolution timer must eventually call + // this function to deactivate the high resolution timer. + static bool ActivateHighResolutionTimer(bool activate); #endif // Converts an exploded structure representing either the local time or UTC @@ -370,6 +388,13 @@ class Time { // platform-dependent epoch. static const int64 kTimeTToMicrosecondsOffset; +#if defined(OS_WIN) + // Indicates whether fast timers are usable right now. For instance, + // when using battery power, we might elect to prevent high speed timers + // which would draw more power. + static bool high_resolution_timer_enabled_; +#endif + // Time in microseconds in UTC. int64 us_; }; |