Updating thread naming.

Also includes experimental code to adapt the thread name as shown by
top, but it's untested.

src/threading/BasicThread.cc

@@ -9,7 +9,7 @@ using namespace threading;
 
 uint64_t BasicThread::thread_counter = 0;
 
-BasicThread::BasicThread(const string& arg_name)
+BasicThread::BasicThread()
 	{
 	started = false;
 	terminating = false;
@@ -18,7 +18,7 @@ BasicThread::BasicThread(const string& arg_name)
 	buf = 0;
 	buf_len = 1024;
 
-	name = Fmt("%s@%d", arg_name.c_str(), ++thread_counter);
+	name = Fmt("thread-%d", ++thread_counter);
 
 	thread_mgr->AddThread(this);
 	}
@@ -27,6 +27,27 @@ BasicThread::~BasicThread()
 	{
 	}
 
+void BasicThread::SetName(const string& arg_name)
+	{
+	// Slight race condition here with reader threads, but shouldn't matter.
+	name = arg_name;
+	}
+
+void BasicThread::SetOSName(const string& name)
+	{
+#ifdef LINUX
+	pthread_setname_np(pthread_self(), name.c_str());
+#endif
+
+#ifdef __APPLE__
+	pthread_setname_np(name.c_str());
+#endif
+
+#ifdef FREEBSD
+	pthread_set_name_np(pthread_self(), name, name.c_str());
+#endif
+	}
+
 const char* BasicThread::Fmt(const char* format, ...)
 	{
 	if ( ! buf )

src/threading/BasicThread.h

@@ -34,16 +34,31 @@ public:
 	 * @param name A descriptive name for thread the thread. This may
 	 * show up in messages to the user.
 	 */
-	BasicThread(const string& name); // Managed by manager, must not delete otherwise.
+	BasicThread();
 
 	/**
-	 * Returns a descriptive name for the thread. This is the name passed
-	 * into the constructor.
+	 * Returns a descriptive name for the thread. If not set via
+	 * SetName(). If not set, a default name is choosen automatically.
 	 *
 	 * This method is safe to call from any thread.
 	 */
 	const string& Name() const { return name; }
 
+	/**
+	* Sets a descriptive name for the thread. This should be a string
+	* that's useful in output presented to the user and uniquely
+	* identifies the thread.
+	*
+	* This method must be called only from the thread itself.
+	*/
+	void SetName(const string& name);
+
+	/**
+	 * Set the name shown by the OS as the thread's description. Not
+	 * supported on all OSs.
+	 */
+	void SetOSName(const string& name);
+
 	/**
 	 * Starts the thread. Calling this methods will spawn a new OS thread
 	 * executing Run(). Note that one can't restart a thread after a

src/threading/MsgThread.cc

@@ -127,7 +127,7 @@ bool ReporterMessage::Process()
 	return true;
 	}
 
-MsgThread::MsgThread(const string& name) : BasicThread(name)
+MsgThread::MsgThread() : BasicThread()
 	{
 	cnt_sent_in = cnt_sent_out = 0;
 	thread_mgr->AddMsgThread(this);
@@ -142,6 +142,12 @@ void MsgThread::OnStop()
 void MsgThread::Heartbeat()
 	{
 	SendIn(new HeartbeatMessage(this, network_time, current_time()));
+
+	string name = Fmt("%s (%d/%d)", name.c_str(),
+			  cnt_sent_in - queue_in.Size(),
+			  cnt_sent_out - queue_out.Size());
+
+	SetOSName(name.c_str());
 	}
 
 void MsgThread::Info(const char* msg)

src/threading/MsgThread.h

@@ -34,10 +34,8 @@ public:
 	 * threading::Manager.
 	 *
 	 * Only Bro's main thread may instantiate a new thread.
-	 *
-	 * @param name A descriptive name. This is passed on to BasicThread().
 	 */
-	MsgThread(const string& name);
+	MsgThread();
 
 	/**
 	 * Sends a message to the child thread. The message will be proceesed