Add simulation generic device/value support

This allows high-level library classes to implement enhanced simulation
support even if no low-level corresponding simulation library exists, and
avoids the need for bit-banging complex interfaces like SPI or CAN.

hal/src/main/native/athena/SimDevice.cpp

@@ -0,0 +1,41 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) 2019 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.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#include "hal/SimDevice.h"
+
+extern "C" {
+
+HAL_SimDeviceHandle HAL_CreateSimDevice(const char* name) { return 0; }
+
+void HAL_FreeSimDevice(HAL_SimDeviceHandle handle) {}
+
+HAL_SimValueHandle HAL_CreateSimValue(HAL_SimDeviceHandle device,
+                                      const char* name, HAL_Bool readonly,
+                                      const struct HAL_Value* initialValue) {
+  return 0;
+}
+
+HAL_SimValueHandle HAL_CreateSimValueEnum(HAL_SimDeviceHandle device,
+                                          const char* name, HAL_Bool readonly,
+                                          int32_t numOptions,
+                                          const char** options,
+                                          int32_t initialValue) {
+  return 0;
+}
+
+void HAL_GetSimValue(HAL_SimValueHandle handle, struct HAL_Value* value) {
+  value->type = HAL_UNASSIGNED;
+}
+
+void HAL_SetSimValue(HAL_SimValueHandle handle, const struct HAL_Value* value) {
+}
+
+hal::SimDevice::SimDevice(const char* name, int index) {}
+
+hal::SimDevice::SimDevice(const char* name, int index, int channel) {}
+
+}  // extern "C"