minix/external/bsd/kyua-cli/dist/utils/datetime.cpp

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// Copyright 2010 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 "utils/datetime.hpp"
extern "C" {
#include <sys/time.h>
#include <time.h>
}
#include "utils/optional.ipp"
#include "utils/sanity.hpp"
namespace datetime = utils::datetime;
using utils::none;
using utils::optional;
namespace {
/// Fake value for the current time.
static optional< datetime::timestamp > mock_now = none;
} // anonymous namespace
/// Creates a zero time delta.
datetime::delta::delta(void) :
seconds(0),
useconds(0)
{
}
/// Creates a time delta.
///
/// \param seconds_ The seconds in the delta.
/// \param useconds_ The microseconds in the delta.
datetime::delta::delta(const int64_t seconds_,
const unsigned long useconds_) :
seconds(seconds_),
useconds(useconds_)
{
}
/// Converts a time expressed in microseconds to a delta.
///
/// \param useconds The amount of microseconds representing the delta.
///
/// \return A new delta object.
datetime::delta
datetime::delta::from_microseconds(const int64_t useconds)
{
return delta(useconds / 1000000, useconds % 1000000);
}
/// Convers the delta to a flat representation expressed in microseconds.
///
/// \return The amount of microseconds that corresponds to this delta.
int64_t
datetime::delta::to_microseconds(void) const
{
return seconds * 1000000 + useconds;
}
/// Checks if two time deltas are equal.
///
/// \param other The object to compare to.
///
/// \return True if the two time deltas are equals; false otherwise.
bool
datetime::delta::operator==(const datetime::delta& other) const
{
return seconds == other.seconds && useconds == other.useconds;
}
/// Checks if two time deltas are different.
///
/// \param other The object to compare to.
///
/// \return True if the two time deltas are different; false otherwise.
bool
datetime::delta::operator!=(const datetime::delta& other) const
{
return !(*this == other);
}
/// Adds a time delta to this one.
///
/// \param other The time delta to add.
///
/// \return The addition of this time delta with the other time delta.
datetime::delta
datetime::delta::operator+(const datetime::delta& other) const
{
return delta::from_microseconds(to_microseconds() +
other.to_microseconds());
}
/// Adds a time delta to this one and updates this with the result.
///
/// \param other The time delta to add.
///
/// \return The addition of this time delta with the other time delta.
datetime::delta
datetime::delta::operator+=(const datetime::delta& other)
{
*this = *this + other;
return *this;
}
/// Injects the object into a stream.
///
/// \param output The stream into which to inject the object.
/// \param object The object to format.
///
/// \return The output stream.
std::ostream&
datetime::operator<<(std::ostream& output, const delta& object)
{
return (output << object.to_microseconds() << "us");
}
namespace utils {
namespace datetime {
/// Internal representation for datetime::timestamp.
struct timestamp::impl {
/// The raw timestamp as provided by libc.
::timeval data;
/// Constructs an impl object from initialized data.
///
/// \param data_ The raw timestamp to use.
impl(const ::timeval& data_) : data(data_)
{
}
};
} // namespace datetime
} // namespace utils
/// Constructs a new timestamp.
///
/// \param pimpl_ An existing impl representation.
datetime::timestamp::timestamp(std::shared_ptr< impl > pimpl_) :
_pimpl(pimpl_)
{
}
/// Constructs a timestamp from the amount of microseconds since the epoch.
///
/// \param value Microseconds since the epoch in UTC. Must be positive.
///
/// \return A new timestamp.
datetime::timestamp
datetime::timestamp::from_microseconds(const int64_t value)
{
PRE(value >= 0);
::timeval data;
data.tv_sec = static_cast< time_t >(value / 1000000);
data.tv_usec = static_cast< suseconds_t >(value % 1000000);
return timestamp(std::shared_ptr< impl >(new impl(data)));
}
/// Constructs a timestamp based on user-friendly values.
///
/// \param year The year in the [1900,inf) range.
/// \param month The month in the [1,12] range.
/// \param day The day in the [1,30] range.
/// \param hour The hour in the [0,23] range.
/// \param minute The minute in the [0,59] range.
/// \param second The second in the [0,60] range. Yes, that is 60, which can be
/// the case on leap seconds.
/// \param microsecond The microsecond in the [0,999999] range.
///
/// \return A new timestamp.
datetime::timestamp
datetime::timestamp::from_values(const int year, const int month,
const int day, const int hour,
const int minute, const int second,
const int microsecond)
{
PRE(year >= 1900);
PRE(month >= 1 && month <= 12);
PRE(day >= 1 && day <= 30);
PRE(hour >= 0 && hour <= 23);
PRE(minute >= 0 && minute <= 59);
PRE(second >= 0 && second <= 60);
PRE(microsecond >= 0 && microsecond <= 999999);
// The code below is quite convoluted. The problem is that we can't assume
// that some fields (like tm_zone) of ::tm exist, and thus we can't blindly
// set them from the code. Instead of detecting their presence in the
// configure script, we just query the current time to initialize such
// fields and then we override the ones we are interested in. (There might
// be some better way to do this, but I don't know it and the documentation
// does not shed much light into how to create your own fake date.)
const time_t current_time = ::time(NULL);
::tm timedata;
if (::gmtime_r(&current_time, &timedata) == NULL)
UNREACHABLE;
timedata.tm_sec = second;
timedata.tm_min = minute;
timedata.tm_hour = hour;
timedata.tm_mday = day;
timedata.tm_mon = month - 1;
timedata.tm_year = year - 1900;
// Ignored: timedata.tm_wday
// Ignored: timedata.tm_yday
::timeval data;
data.tv_sec = ::mktime(&timedata);
data.tv_usec = static_cast< suseconds_t >(microsecond);
return timestamp(std::shared_ptr< impl >(new impl(data)));
}
/// Constructs a new timestamp representing the current time in UTC.
///
/// \return A new timestamp.
datetime::timestamp
datetime::timestamp::now(void)
{
if (mock_now)
return mock_now.get();
::timeval data;
{
#if defined(__minix) && !defined(NDEBUG)
const int ret =
#endif /* defined(__minix) && !defined(NDEBUG) */
::gettimeofday(&data, NULL);
INV(ret != -1);
}
return timestamp(std::shared_ptr< impl >(new impl(data)));
}
/// Formats a timestamp.
///
/// \param format The format string to use as consumed by strftime(3).
///
/// \return The formatted time.
std::string
datetime::timestamp::strftime(const std::string& format) const
{
::tm timedata;
// This conversion to time_t is necessary because tv_sec is not guaranteed
// to be a time_t. For example, it isn't in NetBSD 5.x
::time_t epoch_seconds;
epoch_seconds = _pimpl->data.tv_sec;
if (::gmtime_r(&epoch_seconds, &timedata) == NULL)
UNREACHABLE_MSG("gmtime_r(3) did not accept the value returned by "
"gettimeofday(2)");
char buf[128];
if (::strftime(buf, sizeof(buf), format.c_str(), &timedata) == 0)
UNREACHABLE_MSG("Arbitrary-long format strings are unimplemented");
return buf;
}
/// Returns the number of microseconds since the epoch in UTC.
///
/// \return A number of microseconds.
int64_t
datetime::timestamp::to_microseconds(void) const
{
return static_cast< int64_t >(_pimpl->data.tv_sec) * 1000000 +
_pimpl->data.tv_usec;
}
/// Returns the number of seconds since the epoch in UTC.
///
/// \return A number of seconds.
int64_t
datetime::timestamp::to_seconds(void) const
{
return static_cast< int64_t >(_pimpl->data.tv_sec);
}
/// Sets the current time for testing purposes.
void
datetime::set_mock_now(const int year, const int month,
const int day, const int hour,
const int minute, const int second,
const int microsecond)
{
mock_now = timestamp::from_values(year, month, day, hour, minute, second,
microsecond);
}
/// Checks if two timestamps are equal.
///
/// \param other The object to compare to.
///
/// \return True if the two timestamps are equals; false otherwise.
bool
datetime::timestamp::operator==(const datetime::timestamp& other) const
{
return _pimpl->data.tv_sec == other._pimpl->data.tv_sec &&
_pimpl->data.tv_usec == other._pimpl->data.tv_usec;
}
/// Checks if two timestamps are different.
///
/// \param other The object to compare to.
///
/// \return True if the two timestamps are different; false otherwise.
bool
datetime::timestamp::operator!=(const datetime::timestamp& other) const
{
return !(*this == other);
}
/// Calculates the delta between two timestamps.
///
/// \param other The subtrahend.
///
/// \return The difference between this object and the other object.
datetime::delta
datetime::timestamp::operator-(const datetime::timestamp& other) const
{
return datetime::delta::from_microseconds(to_microseconds() -
other.to_microseconds());
}
/// Injects the object into a stream.
///
/// \param output The stream into which to inject the object.
/// \param object The object to format.
///
/// \return The output stream.
std::ostream&
datetime::operator<<(std::ostream& output, const timestamp& object)
{
return (output << object.to_microseconds() << "us");
}