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/*
* Phusion Passenger - https://www.phusionpassenger.com/
* Copyright (c) 2010-2018 Phusion Holding B.V.
*
* "Passenger", "Phusion Passenger" and "Union Station" are registered
* trademarks of Phusion Holding B.V.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#ifndef _PASSENGER_TIMER_H_
#define _PASSENGER_TIMER_H_
#include <boost/thread.hpp>
#include <oxt/system_calls.hpp>
#include <SystemTools/SystemTime.h>
namespace Passenger {
using namespace boost;
using namespace oxt;
/**
* A Timer which one can use to check how much time has elapsed since the
* timer started. This timer supports miliseconds-resolution, but the exact
* resolution depends on the OS and the hardware.
*
* This class is thread-safe.
*
* @code
* Timer timer;
* sleep(10);
* timer.elapsed(); // => about 10000 (msec)
* @endcode
*/
template<SystemTime::Granularity granularity = SystemTime::GRAN_1USEC>
class Timer {
private:
MonotonicTimeUsec startTime;
mutable boost::mutex lock;
public:
/**
* Creates a new Timer object.
*
* @param startNow Whether the timer should be started immediately.
*/
Timer(bool startNow = true) {
if (startNow) {
start();
} else {
stop();
}
}
/**
* Start the timer. If the timer was already started, then this will
* restart the timer.
*/
void start() {
boost::lock_guard<boost::mutex> l(lock);
startTime = SystemTime::getMonotonicUsecWithGranularity<granularity>();
}
/**
* Stop the timer. If there's currently another thread waiting on the wait()
* call, then that wait() call will block indefinitely until you call start()
* and sufficient amount of time has elapsed.
*/
void stop() {
boost::lock_guard<boost::mutex> l(lock);
startTime = 0;
}
/**
* Resets the timer. If the timer was already started then it is still started;
* if it was stopped then it is still stopped.
*/
void reset() {
boost::lock_guard<boost::mutex> l(lock);
if (startTime != 0) {
startTime = SystemTime::getMonotonicUsecWithGranularity<granularity>();
}
}
/**
* Returns the amount of time that has elapsed since the timer was last started,
* in miliseconds. If the timer is currently stopped, then 0 is returned.
*/
unsigned long long elapsed() const {
boost::lock_guard<boost::mutex> l(lock);
if (startTime == 0) {
return 0;
} else {
return (SystemTime::getMonotonicUsecWithGranularity<granularity>() - startTime) / 1000;
}
}
/**
* Returns the amount of time that has elapsed since the timer was last started,
* in microseconds. If the timer is currently stopped, then 0 is returned.
*/
MonotonicTimeUsec usecElapsed() const {
boost::lock_guard<boost::mutex> l(lock);
if (startTime == 0) {
return 0;
} else {
return SystemTime::getMonotonicUsecWithGranularity<granularity>() - startTime;
}
}
/**
* Wait until <em>time</em> miliseconds have elapsed since the timer
* was last started.
*/
void wait(unsigned long long time) const {
while (elapsed() < time) {
syscalls::usleep(25000);
}
}
};
} // namespace Passenger
#endif /* _PASSENGER_TIMER_H_ */
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