[wpiutil] timestamp: Add ShutdownNowRio (#5610)

ntcoreffi/src/main/native/symbols.txt

@@ -244,6 +244,7 @@ WPI_DestroySemaphore
 WPI_DestroySignalObject
 WPI_GetSystemTime
 WPI_Impl_SetupNowRio
+WPI_Impl_ShutdownNowRio
 WPI_Now
 WPI_NowDefault
 WPI_ReleaseSemaphore

wpiutil/src/main/native/cpp/timestamp.cpp

@@ -92,6 +92,18 @@ struct HMBHolder {
     cfg.Enables_Timestamp = 1;
     hmb->writeConfig(cfg, &status);
   }
+  void Reset() {
+    if (hmb) {
+      std::unique_ptr<fpga::tHMB> oldHmb;
+      oldHmb.swap(hmb);
+      closeHmb(oldHmb->getSystemInterface()->getHandle(), hmbName);
+      closeHmb = nullptr;
+      hmbBuffer = nullptr;
+      oldHmb.reset();
+      dlclose(niFpga);
+      niFpga = nullptr;
+    }
+  }
   std::unique_ptr<fpga::tHMB> hmb;
   void* niFpga = nullptr;
   NiFpga_CloseHmbFunc closeHmb = nullptr;
@@ -182,6 +194,12 @@ void wpi::impl::SetupNowRio() {
 #endif
 }
 
+void wpi::impl::ShutdownNowRio() {
+#ifdef __FRC_ROBORIO__
+  hmb.Reset();
+#endif
+}
+
 void wpi::SetNowImpl(uint64_t (*func)(void)) {
   now_impl = func ? func : NowDefault;
 }
@@ -230,6 +248,10 @@ void WPI_Impl_SetupNowRio(void) {
   return wpi::impl::SetupNowRio();
 }
 
+void WPI_Impl_ShutdownNowRio(void) {
+  return wpi::impl::ShutdownNowRio();
+}
+
 uint64_t WPI_NowDefault(void) {
   return wpi::NowDefault();
 }

wpiutil/src/main/native/include/wpi/timestamp.h

@@ -18,6 +18,12 @@ extern "C" {
  */
 void WPI_Impl_SetupNowRio(void);
 
+/**
+ * De-initialize the on-Rio Now() implementation. No effect on non-Rio
+ * platforms.
+ */
+void WPI_Impl_ShutdownNowRio(void);
+
 /**
  * The default implementation used for Now().
  * In general this is the time returned by the operating system.
@@ -62,6 +68,12 @@ namespace impl {
  * thus should generally not be called by user code.
  */
 void SetupNowRio();
+
+/**
+ * De-initialize the on-Rio Now() implementation. No effect on non-Rio
+ * platforms.
+ */
+void ShutdownNowRio();
 }  // namespace impl
 
 /**