From abb7b710044a2ac8c1b3d3266585f5e183d02c99 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Axel=20D=C3=B6rfler?= <axeld@pinc-software.de>
Date: Fri, 10 Jul 2015 17:05:17 +0200
Subject: [PATCH] launch_daemon: Fixed a race condition in Worker startup.

* When the thread is started during the construction of the base
  class, the virtual method table may still point to the methods
  of the base class when the thread actually starts to run.
* This caused the main worker to have a timeout, which could
  eventually be reached which in turn caused all job processing
  to stop.
* That's what you get when you do Java all day; whoever designed
  C++ should be slapped (I'm talking to you, Bjarne).
---
 src/servers/launch/LaunchDaemon.cpp |  2 ++
 src/servers/launch/Worker.cpp       | 27 +++++++++++++++++++++------
 src/servers/launch/Worker.h         |  2 ++
 3 files changed, 25 insertions(+), 6 deletions(-)

diff --git a/src/servers/launch/LaunchDaemon.cpp b/src/servers/launch/LaunchDaemon.cpp
index 9d56171b59..63a6245aae 100644
--- a/src/servers/launch/LaunchDaemon.cpp
+++ b/src/servers/launch/LaunchDaemon.cpp
@@ -164,6 +164,8 @@ LaunchDaemon::LaunchDaemon(bool userMode, status_t& error)
 	fUserMode(userMode)
 {
 	fMainWorker = new MainWorker(fJobQueue);
+	fMainWorker->Init();
+
 	if (fInitTarget != NULL)
 		_AddTarget(fInitTarget);
 
diff --git a/src/servers/launch/Worker.cpp b/src/servers/launch/Worker.cpp
index d435a179a9..5e337603b4 100644
--- a/src/servers/launch/Worker.cpp
+++ b/src/servers/launch/Worker.cpp
@@ -15,12 +15,9 @@ static int32 sWorkerCount;
 
 Worker::Worker(JobQueue& queue)
 	:
+	fThread(-1),
 	fJobQueue(queue)
 {
-	fThread = spawn_thread(&Worker::_Process, "worker", B_NORMAL_PRIORITY,
-		this);
-	if (fThread >= 0 && resume_thread(fThread) == B_OK)
-		atomic_add(&sWorkerCount, 1);
 }
 
 
@@ -29,6 +26,22 @@ Worker::~Worker()
 }
 
 
+status_t
+Worker::Init()
+{
+	fThread = spawn_thread(&Worker::_Process, "worker", B_NORMAL_PRIORITY,
+		this);
+	if (fThread < 0)
+		return fThread;
+
+	status_t status = resume_thread(fThread);
+	if (status == B_OK)
+		atomic_add(&sWorkerCount, 1);
+
+	return status;
+}
+
+
 status_t
 Worker::Process()
 {
@@ -103,8 +116,10 @@ MainWorker::Run(BJob* job)
 	if (jobCount > INT_MAX)
 		jobCount = INT_MAX;
 
-	if ((int32)jobCount > count && count < fCPUCount)
-		new Worker(fJobQueue);
+	if ((int32)jobCount > count && count < fCPUCount) {
+		Worker* worker = new Worker(fJobQueue);
+		worker->Init();
+	}
 
 	return Worker::Run(job);
 }
diff --git a/src/servers/launch/Worker.h b/src/servers/launch/Worker.h
index bcc3e28aa4..beb333d1f3 100644
--- a/src/servers/launch/Worker.h
+++ b/src/servers/launch/Worker.h
@@ -19,6 +19,8 @@ public:
 								Worker(JobQueue& queue);
 	virtual						~Worker();
 
+			status_t			Init();
+
 protected:
 	virtual	status_t			Process();
 	virtual	bigtime_t			Timeout() const;