Files
allwpilib/wpilibc/src/main/native/include/frc/Watchdog.h
Peter Johnson a2368a6199 Watchdog: add timeout message suppression feature
Was part of reverted #1486
2018-12-30 00:16:50 -08:00

142 lines
3.8 KiB
C++

/*----------------------------------------------------------------------------*/
/* Copyright (c) 2018 FIRST. All Rights Reserved. */
/* Open Source Software - may be modified and shared by FRC teams. The code */
/* must be accompanied by the FIRST BSD license file in the root directory of */
/* the project. */
/*----------------------------------------------------------------------------*/
#pragma once
#include <chrono>
#include <functional>
#include <utility>
#include <hal/cpp/fpga_clock.h>
#include <wpi/SafeThread.h>
#include <wpi/StringMap.h>
#include <wpi/StringRef.h>
namespace frc {
/**
* A class that's a wrapper around a watchdog timer.
*
* When the timer expires, a message is printed to the console and an optional
* user-provided callback is invoked.
*
* The watchdog is initialized disabled, so the user needs to call Enable()
* before use.
*/
class Watchdog {
public:
/**
* Watchdog constructor.
*
* @param timeout The watchdog's timeout in seconds with microsecond
* resolution.
* @param callback This function is called when the timeout expires.
*/
Watchdog(double timeout, std::function<void()> callback);
template <typename Callable, typename Arg, typename... Args>
Watchdog(double timeout, Callable&& f, Arg&& arg, Args&&... args)
: Watchdog(timeout,
std::bind(std::forward<Callable>(f), std::forward<Arg>(arg),
std::forward<Args>(args)...)) {}
~Watchdog();
Watchdog(Watchdog&&) = default;
Watchdog& operator=(Watchdog&&) = default;
/**
* Returns the time in seconds since the watchdog was last fed.
*/
double GetTime() const;
/**
* Sets the watchdog's timeout.
*
* @param timeout The watchdog's timeout in seconds with microsecond
* resolution.
*/
void SetTimeout(double timeout);
/**
* Returns the watchdog's timeout in seconds.
*/
double GetTimeout() const;
/**
* Returns true if the watchdog timer has expired.
*/
bool IsExpired() const;
/**
* Adds time since last epoch to the list printed by PrintEpochs().
*
* Epochs are a way to partition the time elapsed so that when overruns occur,
* one can determine which parts of an operation consumed the most time.
*
* @param epochName The name to associate with the epoch.
*/
void AddEpoch(wpi::StringRef epochName);
/**
* Prints list of epochs added so far and their times.
*/
void PrintEpochs();
/**
* Resets the watchdog timer.
*
* This also enables the timer if it was previously disabled.
*/
void Reset();
/**
* Enables the watchdog timer.
*/
void Enable();
/**
* Disables the watchdog timer.
*/
void Disable();
/**
* Enable or disable suppression of the generic timeout message.
*
* This may be desirable if the user-provided callback already prints a more
* specific message.
*
* @param suppress Whether to suppress generic timeout message.
*/
void SuppressTimeoutMessage(bool suppress);
private:
// Used for timeout print rate-limiting
static constexpr std::chrono::milliseconds kMinPrintPeriod{1000};
hal::fpga_clock::time_point m_startTime;
std::chrono::microseconds m_timeout;
hal::fpga_clock::time_point m_expirationTime;
std::function<void()> m_callback;
hal::fpga_clock::time_point m_lastTimeoutPrintTime = hal::fpga_clock::epoch();
hal::fpga_clock::time_point m_lastEpochsPrintTime = hal::fpga_clock::epoch();
wpi::StringMap<std::chrono::microseconds> m_epochs;
bool m_isExpired = false;
bool m_suppressTimeoutMessage = false;
class Thread;
wpi::SafeThreadOwner<Thread>* m_owner;
bool operator>(const Watchdog& rhs);
static wpi::SafeThreadOwner<Thread>& GetThreadOwner();
};
} // namespace frc