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// Copyright 2008, Google Inc.
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// * Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
// * Redistributions in binary form must reproduce the above
// copyright notice, this list of conditions and the following disclaimer
// in the documentation and/or other materials provided with the
// distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived from
// this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#include "base/time.h"
#include <mach/mach_time.h>
#include <sys/time.h>
#include <time.h>
#include "base/basictypes.h"
#include "base/logging.h"
// The Time routines in this file use standard POSIX routines, or almost-
// standard routines in the case of timegm.
// The TimeTicks routines are Mach-specific.
// Time -----------------------------------------------------------------------
// The internal representation of Time uses time_t directly, so there is no
// offset. The epoch is 1970-01-01 00:00:00 UTC.
// static
const int64 Time::kTimeTToMicrosecondsOffset = GG_INT64_C(0);
// static
int64 Time::CurrentWallclockMicroseconds() {
struct timeval tv;
struct timezone tz = { 0, 0 }; // UTC
if (gettimeofday(&tv, &tz) != 0) {
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 * GG_UINT64_C(1000000) + tv.tv_usec;
}
// static
Time Time::FromExploded(bool is_local, const Exploded& exploded) {
struct tm timestruct;
timestruct.tm_sec = exploded.second;
timestruct.tm_min = exploded.minute;
timestruct.tm_hour = exploded.hour;
timestruct.tm_mday = exploded.day_of_month;
timestruct.tm_mon = exploded.month - 1;
timestruct.tm_year = exploded.year - 1900;
timestruct.tm_wday = exploded.day_of_week; // mktime/timegm ignore this
timestruct.tm_yday = 0; // mktime/timegm ignore this
timestruct.tm_isdst = -1; // attempt to figure it out
timestruct.tm_gmtoff = 0; // not a POSIX field, so mktime/timegm ignore
timestruct.tm_zone = NULL; // not a POSIX field, so mktime/timegm ignore
time_t seconds;
if (is_local)
seconds = mktime(×truct);
else
seconds = timegm(×truct);
DCHECK(seconds >= 0) << "mktime/timegm could not convert from exploded";
uint64 milliseconds = seconds * kMillisecondsPerSecond + exploded.millisecond;
return Time(milliseconds * kMicrosecondsPerMillisecond);
}
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.
uint64 milliseconds = us_ / kMicrosecondsPerMillisecond;
time_t seconds = milliseconds / kMillisecondsPerSecond;
struct tm timestruct;
if (is_local)
localtime_r(&seconds, ×truct);
else
gmtime_r(&seconds, ×truct);
exploded->year = timestruct.tm_year + 1900;
exploded->month = timestruct.tm_mon + 1;
exploded->day_of_week = timestruct.tm_wday;
exploded->day_of_month = timestruct.tm_mday;
exploded->hour = timestruct.tm_hour;
exploded->minute = timestruct.tm_min;
exploded->second = timestruct.tm_sec;
exploded->millisecond = milliseconds % kMillisecondsPerSecond;
}
// TimeTicks ------------------------------------------------------------------
// static
TimeTicks TimeTicks::Now() {
static bool has_timebase_info = false;
static mach_timebase_info_data_t timebase_info;
if (!has_timebase_info) {
has_timebase_info = mach_timebase_info(&timebase_info) == KERN_SUCCESS;
}
DCHECK(has_timebase_info) << "Could not determine system tick rate";
// 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. Divide
// by 1000 to get microseconds up front to stave off overflows.
uint64_t absolute_micro = mach_absolute_time() / 1000 * 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.
return TimeTicks(absolute_micro);
}
// static
TimeTicks TimeTicks::UnreliableHighResNow() {
return Now();
}
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