set thread name (#3664)

* set thread name

* fix dead lock

* fix code style & return fake name

* fix code style

* fix code style

Co-authored-by: Aleksandar Fabijanic <aleks-f@users.noreply.github.com>

Foundation/include/Poco/Thread_POSIX.h

@@ -36,10 +36,8 @@
 #include <cstring>
 #endif
 
-
 namespace Poco {
 
-
 class Foundation_API ThreadImpl
 {
 public:
@@ -64,6 +62,12 @@ public:
 	~ThreadImpl();
 
 	TIDImpl tidImpl() const;
+	void setNameImpl(const std::string& threadName);
+	std::string getNameImpl() const;
+	std::string getOSThreadNameImpl();
+		/// Returns the thread's name, expressed as an operating system
+		/// specific name value. Return empty string if thread is not running.
+		/// For test used only.
 	void setPriorityImpl(int prio);
 	int getPriorityImpl() const;
 	void setOSPriorityImpl(int prio, int policy = SCHED_OTHER);
@@ -141,6 +145,7 @@ private:
 		std::size_t   stackSize;
 		bool          started;
 		bool          joined;
+		std::string   name;
 		mutable FastMutex mutex;
 	};