diff options
Diffstat (limited to 'base/time_posix.cc')
| -rw-r--r-- | base/time_posix.cc | 76 |
1 files changed, 34 insertions, 42 deletions
diff --git a/base/time_posix.cc b/base/time_posix.cc index 8b04be9..66f41d3 100644 --- a/base/time_posix.cc +++ b/base/time_posix.cc @@ -4,9 +4,6 @@ #include "base/time.h" -#ifdef OS_MACOSX -#include <mach/mach_time.h> -#endif #include <sys/time.h> #include <time.h> @@ -23,10 +20,24 @@ namespace base { // Time ----------------------------------------------------------------------- -// Some functions in time.cc use time_t directly, so we provide a zero offset -// for them. The epoch is 1970-01-01 00:00:00 UTC. +// Windows uses a Gregorian epoch of 1601. We need to match this internally +// so that our time representations match across all platforms. See bug 14734. +// irb(main):010:0> Time.at(0).getutc() +// => Thu Jan 01 00:00:00 UTC 1970 +// irb(main):011:0> Time.at(-11644473600).getutc() +// => Mon Jan 01 00:00:00 UTC 1601 +static const int64 kWindowsEpochDeltaSeconds = GG_INT64_C(11644473600); +static const int64 kWindowsEpochDeltaMilliseconds = + kWindowsEpochDeltaSeconds * Time::kMillisecondsPerSecond; + +// static +const int64 Time::kWindowsEpochDeltaMicroseconds = + kWindowsEpochDeltaSeconds * Time::kMicrosecondsPerSecond; + +// Some functions in time.cc use time_t directly, so we provide an offset +// to convert from time_t (Unix epoch) and internal (Windows epoch). // static -const int64 Time::kTimeTToMicrosecondsOffset = GG_INT64_C(0); +const int64 Time::kTimeTToMicrosecondsOffset = kWindowsEpochDeltaMicroseconds; // static Time Time::Now() { @@ -36,8 +47,10 @@ Time Time::Now() { DCHECK(0) << "Could not determine time of day"; } // Combine seconds and microseconds in a 64-bit field containing microseconds - // since the epoch. That's enough for nearly 600 centuries. - return tv.tv_sec * kMicrosecondsPerSecond + tv.tv_usec; + // since the epoch. That's enough for nearly 600 centuries. Adjust from + // Unix (1970) to Windows (1601) epoch. + return Time((tv.tv_sec * kMicrosecondsPerSecond + tv.tv_usec) + + kWindowsEpochDeltaMicroseconds); } // static @@ -100,13 +113,17 @@ Time Time::FromExploded(bool is_local, const Exploded& exploded) { milliseconds = seconds * kMillisecondsPerSecond + exploded.millisecond; } - return Time(milliseconds * kMicrosecondsPerMillisecond); + // Adjust from Unix (1970) to Windows (1601) epoch. + return Time((milliseconds * kMicrosecondsPerMillisecond) + + kWindowsEpochDeltaMicroseconds); } void Time::Explode(bool is_local, Exploded* exploded) const { // Time stores times with microsecond resolution, but Exploded only carries - // millisecond resolution, so begin by being lossy. - int64 milliseconds = us_ / kMicrosecondsPerMillisecond; + // millisecond resolution, so begin by being lossy. Adjust from Windows + // epoch (1601) to Unix epoch (1970); + int64 milliseconds = (us_ - kWindowsEpochDeltaMicroseconds) / + kMicrosecondsPerMillisecond; time_t seconds = milliseconds / kMillisecondsPerSecond; struct tm timestruct; @@ -127,38 +144,13 @@ void Time::Explode(bool is_local, Exploded* exploded) const { // TimeTicks ------------------------------------------------------------------ +#if defined(OS_POSIX) && \ + defined(_POSIX_MONOTONIC_CLOCK) && _POSIX_MONOTONIC_CLOCK >= 0 + // static TimeTicks TimeTicks::Now() { uint64_t absolute_micro; -#if defined(OS_MACOSX) - static mach_timebase_info_data_t timebase_info; - if (timebase_info.denom == 0) { - // Zero-initialization of statics guarantees that denom will be 0 before - // calling mach_timebase_info. mach_timebase_info will never set denom to - // 0 as that would be invalid, so the zero-check can be used to determine - // whether mach_timebase_info has already been called. This is - // recommended by Apple's QA1398. - kern_return_t kr = mach_timebase_info(&timebase_info); - DCHECK(kr == KERN_SUCCESS); - } - - // mach_absolute_time is it when it comes to ticks on the Mac. Other calls - // with less precision (such as TickCount) just call through to - // mach_absolute_time. - - // timebase_info converts absolute time tick units into nanoseconds. Convert - // to microseconds up front to stave off overflows. - absolute_micro = mach_absolute_time() / Time::kNanosecondsPerMicrosecond * - timebase_info.numer / timebase_info.denom; - - // Don't bother with the rollover handling that the Windows version does. - // With numer and denom = 1 (the expected case), the 64-bit absolute time - // reported in nanoseconds is enough to last nearly 585 years. - -#elif defined(OS_POSIX) && \ - defined(_POSIX_MONOTONIC_CLOCK) && _POSIX_MONOTONIC_CLOCK >= 0 - struct timespec ts; if (clock_gettime(CLOCK_MONOTONIC, &ts) != 0) { NOTREACHED() << "clock_gettime(CLOCK_MONOTONIC) failed."; @@ -169,13 +161,13 @@ TimeTicks TimeTicks::Now() { (static_cast<int64>(ts.tv_sec) * Time::kMicrosecondsPerSecond) + (static_cast<int64>(ts.tv_nsec) / Time::kNanosecondsPerMicrosecond); + return TimeTicks(absolute_micro); +} + #else // _POSIX_MONOTONIC_CLOCK #error No usable tick clock function on this platform. #endif // _POSIX_MONOTONIC_CLOCK - return TimeTicks(absolute_micro); -} - // static TimeTicks TimeTicks::HighResNow() { return Now(); |