Squashed 'third_party/allwpilib_2016/' content from commit 7f61816
Change-Id: If9d9245880859cdf580f5d7f77045135d0521ce7
git-subtree-dir: third_party/allwpilib_2016
git-subtree-split: 7f618166ed253a24629934fcf89c3decb0528a3b
diff --git a/wpilibc/Athena/src/Timer.cpp b/wpilibc/Athena/src/Timer.cpp
new file mode 100644
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+++ b/wpilibc/Athena/src/Timer.cpp
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+/*----------------------------------------------------------------------------*/
+/* Copyright (c) FIRST 2008. 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 $(WIND_BASE)/WPILib. */
+/*----------------------------------------------------------------------------*/
+
+#include "Timer.h"
+
+#include <time.h>
+
+#include "HAL/HAL.hpp"
+#include "Utility.h"
+#include <iostream>
+
+/**
+ * Pause the task for a specified time.
+ *
+ * Pause the execution of the program for a specified period of time given in
+ * seconds.
+ * Motors will continue to run at their last assigned values, and sensors will
+ * continue to
+ * update. Only the task containing the wait will pause until the wait time is
+ * expired.
+ *
+ * @param seconds Length of time to pause, in seconds.
+ */
+void Wait(double seconds) {
+ if (seconds < 0.0) return;
+ delaySeconds(seconds);
+}
+
+/**
+ * Return the FPGA system clock time in seconds.
+ * This is deprecated and just forwards to Timer::GetFPGATimestamp().
+ * @return Robot running time in seconds.
+ */
+double GetClock() { return Timer::GetFPGATimestamp(); }
+
+/**
+ * @brief Gives real-time clock system time with nanosecond resolution
+ * @return The time, just in case you want the robot to start autonomous at 8pm
+ * on Saturday.
+*/
+double GetTime() {
+ struct timespec tp;
+
+ clock_gettime(CLOCK_REALTIME, &tp);
+ double realTime = (double)tp.tv_sec + (double)((double)tp.tv_nsec * 1e-9);
+
+ return (realTime);
+}
+
+//for compatibility with msvc12--see C2864
+const double Timer::kRolloverTime = (1ll << 32) / 1e6;
+/**
+ * Create a new timer object.
+ *
+ * Create a new timer object and reset the time to zero. The timer is initially
+ * not running and
+ * must be started.
+ */
+Timer::Timer() {
+ // Creates a semaphore to control access to critical regions.
+ // Initially 'open'
+ Reset();
+}
+
+/**
+ * Get the current time from the timer. If the clock is running it is derived
+ * from
+ * the current system clock the start time stored in the timer class. If the
+ * clock
+ * is not running, then return the time when it was last stopped.
+ *
+ * @return Current time value for this timer in seconds
+ */
+double Timer::Get() const {
+ double result;
+ double currentTime = GetFPGATimestamp();
+
+ std::lock_guard<priority_mutex> sync(m_mutex);
+ if (m_running) {
+ // If the current time is before the start time, then the FPGA clock
+ // rolled over. Compensate by adding the ~71 minutes that it takes
+ // to roll over to the current time.
+ if (currentTime < m_startTime) {
+ currentTime += kRolloverTime;
+ }
+
+ result = (currentTime - m_startTime) + m_accumulatedTime;
+ } else {
+ result = m_accumulatedTime;
+ }
+
+ return result;
+}
+
+/**
+ * Reset the timer by setting the time to 0.
+ *
+ * Make the timer startTime the current time so new requests will be relative to
+ * now
+ */
+void Timer::Reset() {
+ std::lock_guard<priority_mutex> sync(m_mutex);
+ m_accumulatedTime = 0;
+ m_startTime = GetFPGATimestamp();
+}
+
+/**
+ * Start the timer running.
+ * Just set the running flag to true indicating that all time requests should be
+ * relative to the system clock.
+ */
+void Timer::Start() {
+ std::lock_guard<priority_mutex> sync(m_mutex);
+ if (!m_running) {
+ m_startTime = GetFPGATimestamp();
+ m_running = true;
+ }
+}
+
+/**
+ * Stop the timer.
+ * This computes the time as of now and clears the running flag, causing all
+ * subsequent time requests to be read from the accumulated time rather than
+ * looking at the system clock.
+ */
+void Timer::Stop() {
+ double temp = Get();
+
+ std::lock_guard<priority_mutex> sync(m_mutex);
+ if (m_running) {
+ m_accumulatedTime = temp;
+ m_running = false;
+ }
+}
+
+/**
+ * Check if the period specified has passed and if it has, advance the start
+ * time by that period. This is useful to decide if it's time to do periodic
+ * work without drifting later by the time it took to get around to checking.
+ *
+ * @param period The period to check for (in seconds).
+ * @return True if the period has passed.
+ */
+bool Timer::HasPeriodPassed(double period) {
+ if (Get() > period) {
+ std::lock_guard<priority_mutex> sync(m_mutex);
+ // Advance the start time by the period.
+ m_startTime += period;
+ // Don't set it to the current time... we want to avoid drift.
+ return true;
+ }
+ return false;
+}
+
+/**
+ * Return the FPGA system clock time in seconds.
+ *
+ * Return the time from the FPGA hardware clock in seconds since the FPGA
+ * started.
+ * Rolls over after 71 minutes.
+ * @returns Robot running time in seconds.
+ */
+double Timer::GetFPGATimestamp() {
+ // FPGA returns the timestamp in microseconds
+ // Call the helper GetFPGATime() in Utility.cpp
+ return GetFPGATime() * 1.0e-6;
+}
+
+// Internal function that reads the PPC timestamp counter.
+extern "C" {
+uint32_t niTimestamp32(void);
+uint64_t niTimestamp64(void);
+}