From e465aee36abc3f6c52964e8a4fdb0232dd25e996 Mon Sep 17 00:00:00 2001
From: veera venky <veeravenky222@gmail.com>
Date: Wed, 13 Jun 2018 03:06:30 +0530
Subject: [PATCH 1/2] Fix for #4191 (active.json should be removed on JVM
 shutdown)

    Added a shutdown hook to clean up active.json file
---
 main/src/main/scala/sbt/Main.scala | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/main/src/main/scala/sbt/Main.scala b/main/src/main/scala/sbt/Main.scala
index 65b436be0..67bc59857 100644
--- a/main/src/main/scala/sbt/Main.scala
+++ b/main/src/main/scala/sbt/Main.scala
@@ -105,11 +105,18 @@ object StandardMain {
   import scalacache.caffeine._
   private[sbt] lazy val cache: Cache[Any] = CaffeineCache[Any]
 
+  private[sbt] val shutdownHook = new Thread(new Runnable {
+    def run(): Unit = {
+      exchange.shutdown
+    }
+  })
+
   def runManaged(s: State): xsbti.MainResult = {
     val previous = TrapExit.installManager()
     try {
       try {
         try {
+          Runtime.getRuntime.addShutdownHook(shutdownHook)
           MainLoop.runLogged(s)
         } finally exchange.shutdown
       } finally DefaultBackgroundJobService.backgroundJobService.shutdown()

From e3c9eb0cd9dded109deaa08df4da4ad1eb17a265 Mon Sep 17 00:00:00 2001
From: Eugene Yokota <eed3si9n@gmail.com>
Date: Thu, 14 Jun 2018 05:09:00 -0400
Subject: [PATCH 2/2] Remove the shutdown hook when it's done

---
 main/src/main/scala/sbt/Main.scala | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/main/src/main/scala/sbt/Main.scala b/main/src/main/scala/sbt/Main.scala
index 67bc59857..920a0c302 100644
--- a/main/src/main/scala/sbt/Main.scala
+++ b/main/src/main/scala/sbt/Main.scala
@@ -115,10 +115,20 @@ object StandardMain {
     val previous = TrapExit.installManager()
     try {
       try {
-        try {
+        val hooked = try {
           Runtime.getRuntime.addShutdownHook(shutdownHook)
+          true
+        } catch {
+          case _: IllegalArgumentException => false
+        }
+        try {
           MainLoop.runLogged(s)
-        } finally exchange.shutdown
+        } finally {
+          exchange.shutdown
+          if (hooked) {
+            Runtime.getRuntime.removeShutdownHook(shutdownHook)
+          }
+        }
       } finally DefaultBackgroundJobService.backgroundJobService.shutdown()
     } finally TrapExit.uninstallManager(previous)
   }