From ee8a33c5685a915d9c8650191138f39d01eee994 Mon Sep 17 00:00:00 2001
From: Peter Johnson <johnson.peter@gmail.com>
Date: Thu, 20 Jun 2019 19:51:09 -0700
Subject: [PATCH] wpiutil: SafeThread: Add thread id, support getting
 shared_ptr (#1722)

Rename base class function from GetThread to GetThreadSharedPtr.
---
 wpiutil/src/main/native/cpp/SafeThread.cpp       |  6 ++++--
 wpiutil/src/main/native/include/wpi/SafeThread.h | 10 ++++++++--
 2 files changed, 12 insertions(+), 4 deletions(-)

diff --git a/wpiutil/src/main/native/cpp/SafeThread.cpp b/wpiutil/src/main/native/cpp/SafeThread.cpp
index 52ac70077e..1d0fc0f41a 100644
--- a/wpiutil/src/main/native/cpp/SafeThread.cpp
+++ b/wpiutil/src/main/native/cpp/SafeThread.cpp
@@ -1,5 +1,5 @@
 /*----------------------------------------------------------------------------*/
-/* Copyright (c) 2015-2018 FIRST. All Rights Reserved.                        */
+/* Copyright (c) 2015-2019 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.                                                               */
@@ -32,6 +32,7 @@ void detail::SafeThreadOwnerBase::Start(std::shared_ptr<SafeThread> thr) {
   std::lock_guard<wpi::mutex> lock(m_mutex);
   if (auto thr = m_thread.lock()) return;
   m_stdThread = std::thread([=] { thr->Main(); });
+  thr->m_threadId = m_stdThread.get_id();
   m_thread = thr;
 }
 
@@ -80,7 +81,8 @@ detail::SafeThreadOwnerBase::GetNativeThreadHandle() {
   return m_stdThread.native_handle();
 }
 
-std::shared_ptr<SafeThread> detail::SafeThreadOwnerBase::GetThread() const {
+std::shared_ptr<SafeThread> detail::SafeThreadOwnerBase::GetThreadSharedPtr()
+    const {
   std::lock_guard<wpi::mutex> lock(m_mutex);
   return m_thread.lock();
 }
diff --git a/wpiutil/src/main/native/include/wpi/SafeThread.h b/wpiutil/src/main/native/include/wpi/SafeThread.h
index a2de41426e..d4b48f7b14 100644
--- a/wpiutil/src/main/native/include/wpi/SafeThread.h
+++ b/wpiutil/src/main/native/include/wpi/SafeThread.h
@@ -27,6 +27,7 @@ class SafeThread {
   mutable wpi::mutex m_mutex;
   std::atomic_bool m_active{true};
   wpi::condition_variable m_cond;
+  std::thread::id m_threadId;
 };
 
 namespace detail {
@@ -83,7 +84,7 @@ class SafeThreadOwnerBase {
 
  protected:
   void Start(std::shared_ptr<SafeThread> thr);
-  std::shared_ptr<SafeThread> GetThread() const;
+  std::shared_ptr<SafeThread> GetThreadSharedPtr() const;
 
  private:
   mutable wpi::mutex m_mutex;
@@ -107,7 +108,12 @@ class SafeThreadOwner : public detail::SafeThreadOwnerBase {
 
   using Proxy = typename detail::SafeThreadProxy<T>;
   Proxy GetThread() const {
-    return Proxy(detail::SafeThreadOwnerBase::GetThread());
+    return Proxy(detail::SafeThreadOwnerBase::GetThreadSharedPtr());
+  }
+
+  std::shared_ptr<T> GetThreadSharedPtr() const {
+    return std::static_pointer_cast<T>(
+        detail::SafeThreadOwnerBase::GetThreadSharedPtr());
   }
 };