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/MotorSafetyHelper.cpp b/wpilibc/Athena/src/MotorSafetyHelper.cpp
new file mode 100644
index 0000000..60bba30
--- /dev/null
+++ b/wpilibc/Athena/src/MotorSafetyHelper.cpp
@@ -0,0 +1,139 @@
+/*----------------------------------------------------------------------------*/
+/* 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 "MotorSafetyHelper.h"
+
+#include "DriverStation.h"
+#include "MotorSafety.h"
+#include "Timer.h"
+#include "WPIErrors.h"
+
+#include <stdio.h>
+#include <sstream>
+
+std::set<MotorSafetyHelper*> MotorSafetyHelper::m_helperList;
+priority_recursive_mutex MotorSafetyHelper::m_listMutex;
+
+/**
+ * The constructor for a MotorSafetyHelper object.
+ * The helper object is constructed for every object that wants to implement the
+ * Motor
+ * Safety protocol. The helper object has the code to actually do the timing and
+ * call the
+ * motors Stop() method when the timeout expires. The motor object is expected
+ * to call the
+ * Feed() method whenever the motors value is updated.
+ * @param safeObject a pointer to the motor object implementing MotorSafety.
+ * This is used
+ * to call the Stop() method on the motor.
+ */
+MotorSafetyHelper::MotorSafetyHelper(MotorSafety *safeObject)
+ : m_safeObject(safeObject) {
+ m_enabled = false;
+ m_expiration = DEFAULT_SAFETY_EXPIRATION;
+ m_stopTime = Timer::GetFPGATimestamp();
+
+ std::lock_guard<priority_recursive_mutex> sync(m_listMutex);
+ m_helperList.insert(this);
+}
+
+MotorSafetyHelper::~MotorSafetyHelper() {
+ std::lock_guard<priority_recursive_mutex> sync(m_listMutex);
+ m_helperList.erase(this);
+}
+
+/**
+ * Feed the motor safety object.
+ * Resets the timer on this object that is used to do the timeouts.
+ */
+void MotorSafetyHelper::Feed() {
+ std::lock_guard<priority_recursive_mutex> sync(m_syncMutex);
+ m_stopTime = Timer::GetFPGATimestamp() + m_expiration;
+}
+
+/**
+ * Set the expiration time for the corresponding motor safety object.
+ * @param expirationTime The timeout value in seconds.
+ */
+void MotorSafetyHelper::SetExpiration(float expirationTime) {
+ std::lock_guard<priority_recursive_mutex> sync(m_syncMutex);
+ m_expiration = expirationTime;
+}
+
+/**
+ * Retrieve the timeout value for the corresponding motor safety object.
+ * @return the timeout value in seconds.
+ */
+float MotorSafetyHelper::GetExpiration() const {
+ std::lock_guard<priority_recursive_mutex> sync(m_syncMutex);
+ return m_expiration;
+}
+
+/**
+ * Determine if the motor is still operating or has timed out.
+ * @return a true value if the motor is still operating normally and hasn't
+ * timed out.
+ */
+bool MotorSafetyHelper::IsAlive() const {
+ std::lock_guard<priority_recursive_mutex> sync(m_syncMutex);
+ return !m_enabled || m_stopTime > Timer::GetFPGATimestamp();
+}
+
+/**
+ * Check if this motor has exceeded its timeout.
+ * This method is called periodically to determine if this motor has exceeded
+ * its timeout
+ * value. If it has, the stop method is called, and the motor is shut down until
+ * its value is
+ * updated again.
+ */
+void MotorSafetyHelper::Check() {
+ DriverStation &ds = DriverStation::GetInstance();
+ if (!m_enabled || ds.IsDisabled() || ds.IsTest()) return;
+
+ std::lock_guard<priority_recursive_mutex> sync(m_syncMutex);
+ if (m_stopTime < Timer::GetFPGATimestamp()) {
+ std::ostringstream desc;
+ m_safeObject->GetDescription(desc);
+ desc << "... Output not updated often enough.";
+ wpi_setWPIErrorWithContext(Timeout, desc.str().c_str());
+ m_safeObject->StopMotor();
+ }
+}
+
+/**
+ * Enable/disable motor safety for this device
+ * Turn on and off the motor safety option for this PWM object.
+ * @param enabled True if motor safety is enforced for this object
+ */
+void MotorSafetyHelper::SetSafetyEnabled(bool enabled) {
+ std::lock_guard<priority_recursive_mutex> sync(m_syncMutex);
+ m_enabled = enabled;
+}
+
+/**
+ * Return the state of the motor safety enabled flag
+ * Return if the motor safety is currently enabled for this devicce.
+ * @return True if motor safety is enforced for this device
+ */
+bool MotorSafetyHelper::IsSafetyEnabled() const {
+ std::lock_guard<priority_recursive_mutex> sync(m_syncMutex);
+ return m_enabled;
+}
+
+/**
+ * Check the motors to see if any have timed out.
+ * This static method is called periodically to poll all the motors and stop
+ * any that have
+ * timed out.
+ */
+void MotorSafetyHelper::CheckMotors() {
+ std::lock_guard<priority_recursive_mutex> sync(m_listMutex);
+ for (auto elem : m_helperList) {
+ elem->Check();
+ }
+}