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// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "base/time/time.h"
#include <cmath>
#include <ios>
#include <limits>
#include <ostream>
#include <sstream>
#include "base/logging.h"
#include "base/macros.h"
#include "base/no_destructor.h"
#include "base/strings/stringprintf.h"
#include "base/third_party/nspr/prtime.h"
#include "base/time/time_override.h"
#include "build/build_config.h"
namespace base {
namespace internal {
TimeNowFunction g_time_now_function = &subtle::TimeNowIgnoringOverride;
TimeNowFunction g_time_now_from_system_time_function =
&subtle::TimeNowFromSystemTimeIgnoringOverride;
TimeTicksNowFunction g_time_ticks_now_function =
&subtle::TimeTicksNowIgnoringOverride;
ThreadTicksNowFunction g_thread_ticks_now_function =
&subtle::ThreadTicksNowIgnoringOverride;
} // namespace internal
// TimeDelta ------------------------------------------------------------------
int TimeDelta::InDays() const {
if (is_max()) {
// Preserve max to prevent overflow.
return std::numeric_limits<int>::max();
}
return static_cast<int>(delta_ / Time::kMicrosecondsPerDay);
}
int TimeDelta::InDaysFloored() const {
if (is_max()) {
// Preserve max to prevent overflow.
return std::numeric_limits<int>::max();
}
int result = delta_ / Time::kMicrosecondsPerDay;
int64_t remainder = delta_ - (result * Time::kMicrosecondsPerDay);
if (remainder < 0) {
--result; // Use floor(), not trunc() rounding behavior.
}
return result;
}
int TimeDelta::InHours() const {
if (is_max()) {
// Preserve max to prevent overflow.
return std::numeric_limits<int>::max();
}
return static_cast<int>(delta_ / Time::kMicrosecondsPerHour);
}
int TimeDelta::InMinutes() const {
if (is_max()) {
// Preserve max to prevent overflow.
return std::numeric_limits<int>::max();
}
return static_cast<int>(delta_ / Time::kMicrosecondsPerMinute);
}
double TimeDelta::InSecondsF() const {
if (is_max()) {
// Preserve max to prevent overflow.
return std::numeric_limits<double>::infinity();
}
return static_cast<double>(delta_) / Time::kMicrosecondsPerSecond;
}
int64_t TimeDelta::InSeconds() const {
if (is_max()) {
// Preserve max to prevent overflow.
return std::numeric_limits<int64_t>::max();
}
return delta_ / Time::kMicrosecondsPerSecond;
}
double TimeDelta::InMillisecondsF() const {
if (is_max()) {
// Preserve max to prevent overflow.
return std::numeric_limits<double>::infinity();
}
return static_cast<double>(delta_) / Time::kMicrosecondsPerMillisecond;
}
int64_t TimeDelta::InMilliseconds() const {
if (is_max()) {
// Preserve max to prevent overflow.
return std::numeric_limits<int64_t>::max();
}
return delta_ / Time::kMicrosecondsPerMillisecond;
}
int64_t TimeDelta::InMillisecondsRoundedUp() const {
if (is_max()) {
// Preserve max to prevent overflow.
return std::numeric_limits<int64_t>::max();
}
int64_t result = delta_ / Time::kMicrosecondsPerMillisecond;
int64_t remainder = delta_ - (result * Time::kMicrosecondsPerMillisecond);
if (remainder > 0) {
++result; // Use ceil(), not trunc() rounding behavior.
}
return result;
}
double TimeDelta::InMicrosecondsF() const {
if (is_max()) {
// Preserve max to prevent overflow.
return std::numeric_limits<double>::infinity();
}
return static_cast<double>(delta_);
}
int64_t TimeDelta::InNanoseconds() const {
if (is_max()) {
// Preserve max to prevent overflow.
return std::numeric_limits<int64_t>::max();
}
return delta_ * Time::kNanosecondsPerMicrosecond;
}
std::ostream& operator<<(std::ostream& os, TimeDelta time_delta) {
return os << time_delta.InSecondsF() << " s";
}
// Time -----------------------------------------------------------------------
// static
Time Time::Now() {
return internal::g_time_now_function();
}
// static
Time Time::NowFromSystemTime() {
// Just use g_time_now_function because it returns the system time.
return internal::g_time_now_from_system_time_function();
}
// static
Time Time::FromDeltaSinceWindowsEpoch(TimeDelta delta) {
return Time(delta.InMicroseconds());
}
TimeDelta Time::ToDeltaSinceWindowsEpoch() const {
return TimeDelta::FromMicroseconds(us_);
}
// static
Time Time::FromTimeT(time_t tt) {
if (tt == 0)
return Time(); // Preserve 0 so we can tell it doesn't exist.
if (tt == std::numeric_limits<time_t>::max())
return Max();
return Time(kTimeTToMicrosecondsOffset) + TimeDelta::FromSeconds(tt);
}
time_t Time::ToTimeT() const {
if (is_null())
return 0; // Preserve 0 so we can tell it doesn't exist.
if (is_max()) {
// Preserve max without offset to prevent overflow.
return std::numeric_limits<time_t>::max();
}
if (std::numeric_limits<int64_t>::max() - kTimeTToMicrosecondsOffset <= us_) {
DLOG(WARNING) << "Overflow when converting base::Time with internal " <<
"value " << us_ << " to time_t.";
return std::numeric_limits<time_t>::max();
}
return (us_ - kTimeTToMicrosecondsOffset) / kMicrosecondsPerSecond;
}
// static
Time Time::FromDoubleT(double dt) {
if (dt == 0 || std::isnan(dt))
return Time(); // Preserve 0 so we can tell it doesn't exist.
return Time(kTimeTToMicrosecondsOffset) + TimeDelta::FromSecondsD(dt);
}
double Time::ToDoubleT() const {
if (is_null())
return 0; // Preserve 0 so we can tell it doesn't exist.
if (is_max()) {
// Preserve max without offset to prevent overflow.
return std::numeric_limits<double>::infinity();
}
return (static_cast<double>(us_ - kTimeTToMicrosecondsOffset) /
static_cast<double>(kMicrosecondsPerSecond));
}
#if defined(OS_POSIX)
// static
Time Time::FromTimeSpec(const timespec& ts) {
return FromDoubleT(ts.tv_sec +
static_cast<double>(ts.tv_nsec) /
base::Time::kNanosecondsPerSecond);
}
#endif
// static
Time Time::FromJsTime(double ms_since_epoch) {
// The epoch is a valid time, so this constructor doesn't interpret
// 0 as the null time.
return Time(kTimeTToMicrosecondsOffset) +
TimeDelta::FromMillisecondsD(ms_since_epoch);
}
double Time::ToJsTime() const {
if (is_null()) {
// Preserve 0 so the invalid result doesn't depend on the platform.
return 0;
}
return ToJsTimeIgnoringNull();
}
double Time::ToJsTimeIgnoringNull() const {
if (is_max()) {
// Preserve max without offset to prevent overflow.
return std::numeric_limits<double>::infinity();
}
return (static_cast<double>(us_ - kTimeTToMicrosecondsOffset) /
kMicrosecondsPerMillisecond);
}
Time Time::FromJavaTime(int64_t ms_since_epoch) {
return base::Time::UnixEpoch() +
base::TimeDelta::FromMilliseconds(ms_since_epoch);
}
int64_t Time::ToJavaTime() const {
if (is_null()) {
// Preserve 0 so the invalid result doesn't depend on the platform.
return 0;
}
if (is_max()) {
// Preserve max without offset to prevent overflow.
return std::numeric_limits<int64_t>::max();
}
return ((us_ - kTimeTToMicrosecondsOffset) /
kMicrosecondsPerMillisecond);
}
// static
Time Time::UnixEpoch() {
Time time;
time.us_ = kTimeTToMicrosecondsOffset;
return time;
}
Time Time::Midnight(bool is_local) const {
Exploded exploded;
Explode(is_local, &exploded);
exploded.hour = 0;
exploded.minute = 0;
exploded.second = 0;
exploded.millisecond = 0;
Time out_time;
if (FromExploded(is_local, exploded, &out_time)) {
return out_time;
} else if (is_local) {
// Hitting this branch means 00:00:00am of the current day
// does not exist (due to Daylight Saving Time in some countries
// where clocks are shifted at midnight). In this case, midnight
// should be defined as 01:00:00am.
exploded.hour = 1;
if (FromExploded(is_local, exploded, &out_time))
return out_time;
}
// This function must not fail.
NOTREACHED();
return Time();
}
#if !defined(MOZ_SANDBOX)
// static
bool Time::FromStringInternal(const char* time_string,
bool is_local,
Time* parsed_time) {
DCHECK((time_string != nullptr) && (parsed_time != nullptr));
if (time_string[0] == '\0')
return false;
PRTime result_time = 0;
PRStatus result = PR_ParseTimeString(time_string,
is_local ? PR_FALSE : PR_TRUE,
&result_time);
if (PR_SUCCESS != result)
return false;
result_time += kTimeTToMicrosecondsOffset;
*parsed_time = Time(result_time);
return true;
}
#endif
// static
bool Time::ExplodedMostlyEquals(const Exploded& lhs, const Exploded& rhs) {
return lhs.year == rhs.year && lhs.month == rhs.month &&
lhs.day_of_month == rhs.day_of_month && lhs.hour == rhs.hour &&
lhs.minute == rhs.minute && lhs.second == rhs.second &&
lhs.millisecond == rhs.millisecond;
}
// static
bool Time::FromMillisecondsSinceUnixEpoch(int64_t unix_milliseconds,
Time* time) {
// Adjust the provided time from milliseconds since the Unix epoch (1970) to
// microseconds since the Windows epoch (1601), avoiding overflows.
base::CheckedNumeric<int64_t> checked_microseconds_win_epoch =
unix_milliseconds;
checked_microseconds_win_epoch *= kMicrosecondsPerMillisecond;
checked_microseconds_win_epoch += kTimeTToMicrosecondsOffset;
if (!checked_microseconds_win_epoch.IsValid()) {
*time = base::Time(0);
return false;
}
*time = Time(checked_microseconds_win_epoch.ValueOrDie());
return true;
}
int64_t Time::ToRoundedDownMillisecondsSinceUnixEpoch() const {
// Adjust from Windows epoch (1601) to Unix epoch (1970).
int64_t microseconds = us_ - kTimeTToMicrosecondsOffset;
// Round the microseconds towards -infinity.
if (microseconds >= 0) {
// In this case, rounding towards -infinity means rounding towards 0.
return microseconds / kMicrosecondsPerMillisecond;
} else {
return (microseconds - kMicrosecondsPerMillisecond + 1) /
kMicrosecondsPerMillisecond;
}
}
std::ostream& operator<<(std::ostream& os, Time time) {
Time::Exploded exploded;
time.UTCExplode(&exploded);
// Use StringPrintf because iostreams formatting is painful.
return os << StringPrintf("%04d-%02d-%02d %02d:%02d:%02d.%03d UTC",
exploded.year,
exploded.month,
exploded.day_of_month,
exploded.hour,
exploded.minute,
exploded.second,
exploded.millisecond);
}
// TimeTicks ------------------------------------------------------------------
// static
TimeTicks TimeTicks::Now() {
return internal::g_time_ticks_now_function();
}
// static
TimeTicks TimeTicks::UnixEpoch() {
static const base::NoDestructor<base::TimeTicks> epoch([]() {
return subtle::TimeTicksNowIgnoringOverride() -
(subtle::TimeNowIgnoringOverride() - Time::UnixEpoch());
}());
return *epoch;
}
TimeTicks TimeTicks::SnappedToNextTick(TimeTicks tick_phase,
TimeDelta tick_interval) const {
// |interval_offset| is the offset from |this| to the next multiple of
// |tick_interval| after |tick_phase|, possibly negative if in the past.
TimeDelta interval_offset = (tick_phase - *this) % tick_interval;
// If |this| is exactly on the interval (i.e. offset==0), don't adjust.
// Otherwise, if |tick_phase| was in the past, adjust forward to the next
// tick after |this|.
if (!interval_offset.is_zero() && tick_phase < *this)
interval_offset += tick_interval;
return *this + interval_offset;
}
std::ostream& operator<<(std::ostream& os, TimeTicks time_ticks) {
// This function formats a TimeTicks object as "bogo-microseconds".
// The origin and granularity of the count are platform-specific, and may very
// from run to run. Although bogo-microseconds usually roughly correspond to
// real microseconds, the only real guarantee is that the number never goes
// down during a single run.
const TimeDelta as_time_delta = time_ticks - TimeTicks();
return os << as_time_delta.InMicroseconds() << " bogo-microseconds";
}
// ThreadTicks ----------------------------------------------------------------
// static
ThreadTicks ThreadTicks::Now() {
return internal::g_thread_ticks_now_function();
}
std::ostream& operator<<(std::ostream& os, ThreadTicks thread_ticks) {
const TimeDelta as_time_delta = thread_ticks - ThreadTicks();
return os << as_time_delta.InMicroseconds() << " bogo-thread-microseconds";
}
// Time::Exploded -------------------------------------------------------------
inline bool is_in_range(int value, int lo, int hi) {
return lo <= value && value <= hi;
}
bool Time::Exploded::HasValidValues() const {
return is_in_range(month, 1, 12) &&
is_in_range(day_of_week, 0, 6) &&
is_in_range(day_of_month, 1, 31) &&
is_in_range(hour, 0, 23) &&
is_in_range(minute, 0, 59) &&
is_in_range(second, 0, 60) &&
is_in_range(millisecond, 0, 999);
}
} // namespace base