[wpilib] Add new counter implementations (#2447)

wpilibc/src/main/native/include/frc/counter/ExternalDirectionCounter.h

@@ -0,0 +1,79 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+#pragma once
+
+#include <memory>
+
+#include <hal/Types.h>
+#include <wpi/sendable/Sendable.h>
+#include <wpi/sendable/SendableHelper.h>
+
+#include "EdgeConfiguration.h"
+
+namespace frc {
+class DigitalSource;
+
+/** Counter using external direction. */
+class ExternalDirectionCounter
+    : public wpi::Sendable,
+      public wpi::SendableHelper<ExternalDirectionCounter> {
+ public:
+  /**
+   * Constructs a new ExternalDirectionCounter.
+   *
+   * @param countSource The source for counting.
+   * @param directionSource The source for selecting count direction.
+   */
+  ExternalDirectionCounter(DigitalSource& countSource,
+                           DigitalSource& directionSource);
+
+  /**
+   * Constructs a new ExternalDirectionCounter.
+   *
+   * @param countSource The source for counting.
+   * @param directionSource The source for selecting count direction.
+   */
+  ExternalDirectionCounter(std::shared_ptr<DigitalSource> countSource,
+                           std::shared_ptr<DigitalSource> directionSource);
+
+  ~ExternalDirectionCounter() override;
+
+  ExternalDirectionCounter(ExternalDirectionCounter&&) = default;
+  ExternalDirectionCounter& operator=(ExternalDirectionCounter&&) = default;
+
+  /**
+   * Gets the current count.
+   *
+   * @return The current count.
+   */
+  int GetCount() const;
+
+  /**
+   * Sets to revert the counter direction.
+   *
+   * @param reverseDirection True to reverse counting direction.
+   */
+  void SetReverseDirection(bool reverseDirection);
+
+  /** Resets the current count. */
+  void Reset();
+
+  /**
+   * Sets the edge configuration for counting.
+   *
+   * @param configuration The counting edge configuration.
+   */
+  void SetEdgeConfiguration(EdgeConfiguration configuration);
+
+ protected:
+  void InitSendable(wpi::SendableBuilder& builder) override;
+
+ private:
+  std::shared_ptr<DigitalSource> m_countSource;
+  std::shared_ptr<DigitalSource> m_directionSource;
+  hal::Handle<HAL_CounterHandle> m_handle;
+  int32_t m_index = 0;
+};
+}  // namespace frc