Prepare ntcore for merge into allwpilib.

ntcore/src/main/native/cpp/EntryNotifier.h

@@ -0,0 +1,109 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) FIRST 2015-2018. 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.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#ifndef NTCORE_ENTRYNOTIFIER_H_
+#define NTCORE_ENTRYNOTIFIER_H_
+
+#include <atomic>
+#include <memory>
+#include <string>
+
+#include "CallbackManager.h"
+#include "Handle.h"
+#include "IEntryNotifier.h"
+#include "ntcore_cpp.h"
+
+namespace wpi {
+class Logger;
+}  // namespace wpi
+
+namespace nt {
+
+namespace impl {
+
+struct EntryListenerData
+    : public ListenerData<std::function<void(const EntryNotification& event)>> {
+  EntryListenerData() = default;
+  EntryListenerData(
+      std::function<void(const EntryNotification& event)> callback_,
+      StringRef prefix_, unsigned int flags_)
+      : ListenerData(callback_), prefix(prefix_), flags(flags_) {}
+  EntryListenerData(
+      std::function<void(const EntryNotification& event)> callback_,
+      NT_Entry entry_, unsigned int flags_)
+      : ListenerData(callback_), entry(entry_), flags(flags_) {}
+  EntryListenerData(unsigned int poller_uid_, StringRef prefix_,
+                    unsigned int flags_)
+      : ListenerData(poller_uid_), prefix(prefix_), flags(flags_) {}
+  EntryListenerData(unsigned int poller_uid_, NT_Entry entry_,
+                    unsigned int flags_)
+      : ListenerData(poller_uid_), entry(entry_), flags(flags_) {}
+
+  std::string prefix;
+  NT_Entry entry = 0;
+  unsigned int flags;
+};
+
+class EntryNotifierThread
+    : public CallbackThread<EntryNotifierThread, EntryNotification,
+                            EntryListenerData> {
+ public:
+  explicit EntryNotifierThread(int inst) : m_inst(inst) {}
+
+  bool Matches(const EntryListenerData& listener,
+               const EntryNotification& data);
+
+  void SetListener(EntryNotification* data, unsigned int listener_uid) {
+    data->listener =
+        Handle(m_inst, listener_uid, Handle::kEntryListener).handle();
+  }
+
+  void DoCallback(std::function<void(const EntryNotification& event)> callback,
+                  const EntryNotification& data) {
+    callback(data);
+  }
+
+  int m_inst;
+};
+
+}  // namespace impl
+
+class EntryNotifier
+    : public IEntryNotifier,
+      public CallbackManager<EntryNotifier, impl::EntryNotifierThread> {
+  friend class EntryNotifierTest;
+  friend class CallbackManager<EntryNotifier, impl::EntryNotifierThread>;
+
+ public:
+  explicit EntryNotifier(int inst, wpi::Logger& logger);
+
+  void Start();
+
+  bool local_notifiers() const override;
+
+  unsigned int Add(std::function<void(const EntryNotification& event)> callback,
+                   llvm::StringRef prefix, unsigned int flags) override;
+  unsigned int Add(std::function<void(const EntryNotification& event)> callback,
+                   unsigned int local_id, unsigned int flags) override;
+  unsigned int AddPolled(unsigned int poller_uid, llvm::StringRef prefix,
+                         unsigned int flags) override;
+  unsigned int AddPolled(unsigned int poller_uid, unsigned int local_id,
+                         unsigned int flags) override;
+
+  void NotifyEntry(unsigned int local_id, StringRef name,
+                   std::shared_ptr<Value> value, unsigned int flags,
+                   unsigned int only_listener = UINT_MAX) override;
+
+ private:
+  int m_inst;
+  wpi::Logger& m_logger;
+  std::atomic_bool m_local_notifiers;
+};
+
+}  // namespace nt
+
+#endif  // NTCORE_ENTRYNOTIFIER_H_