2014 network limit 1.3 fix log/path/data +utils

+toc -doc -drmonero

Fixed the windows path, and improved logging and data
(for graph) logging, fixed some locks and added more checks.

Still there is a locking error,
not added by my patches, but present in master version
(locking of map/list of peers).

.gitignore

@@ -59,7 +59,6 @@ version/
 ### CMake ###
 CMakeCache.txt
 CMakeFiles
-Makefile
 cmake_install.cmake
 install_manifest.txt
 *.cmake

contrib/otshell_utils/utils.cpp

@@ -160,7 +160,7 @@ std::unique_ptr<T> make_unique( Args&& ...args )
 #endif
 // ====================================================================
 
-char cFilesystemUtils::GetDirSeparator() {
+char cFilesystemUtils::GetDirSeparatorSys() {
 	// TODO nicer os detection?
 	#if defined(OS_TYPE_POSIX)
 		return '/';
@@ -171,26 +171,49 @@ char cFilesystemUtils::GetDirSeparator() {
 	#endif
 }
 
+char cFilesystemUtils::GetDirSeparatorInter() {
+	return '/';
+}
+
+string cFilesystemUtils::FileInternalToSystem(const std::string &name) {
+	string ret;
+	ret.resize(name.size());
+	std::replace_copy(name.begin(), name.end(), ret.begin(), 
+		GetDirSeparatorInter() , GetDirSeparatorSys());
+	return ret;
+}
+
+string cFilesystemUtils::FileSystemToInternal(const std::string &name) {
+	string ret;
+	ret.reserve(name.size());
+	std::replace_copy(name.begin(), name.end(), ret.begin(), 
+		GetDirSeparatorSys() , GetDirSeparatorInter());
+	return ret;
+}
+
 bool cFilesystemUtils::CreateDirTree(const std::string & dir, bool only_below) {
 	const bool dbg=false;
 	//struct stat st;
-	const char dirch = cFilesystemUtils::GetDirSeparator();
+	const char dirchS = cFilesystemUtils::GetDirSeparatorSys();
+	const char dirchI = cFilesystemUtils::GetDirSeparatorInter();
 	std::istringstream iss(dir);
-	string part, sofar="";
+	string partI; // current par is in internal format (though it should not matter since it doesn't contain any slashes). eg "bar"
+	string sofarS=""; // sofarS - the so far created dir part is in SYSTEM format. eg "foo/bar"
 	if (dir.size()<1) return false; // illegal name
 	// dir[0] is valid from here
-	if  (only_below && (dir[0]==dirch)) return false; // no jumping to top (on any os)
-	while (getline(iss,part,dirch)) {
-		if (dbg) cout << '['<<part<<']' << endl;
-		sofar += part;
-		if (part.size()<1) return false; // bad format?
-		if ((only_below) && (part=="..")) return false; // going up
+	if  ( only_below  &&  ((dir[0]==dirchS) || (dir[0]==dirchI))) return false; // no jumping to top (on any os)
 
-		if (dbg) cout << "test ["<<sofar<<"]"<<endl;
+	while (getline(iss,partI,dirchI)) { // get new component eg "bar" into part
+		if (dbg) cout << '['<<partI<<']' << endl;
+		sofarS += partI;
+		if (partI.size()<1) return false; // bad format?
+		if ((only_below) && (partI=="..")) return false; // trying to go up
+
+		if (dbg) cout << "test ["<<sofarS<<"]"<<endl;
 		// TODO nicer os detection?
 		#if defined(OS_TYPE_POSIX)
 			struct stat st;
-			bool exists = stat(sofar.c_str() ,&st) == 0; // *
+			bool exists = stat(sofarS.c_str() ,&st) == 0; // *
 			if (exists) {
 				if (! S_ISDIR(st.st_mode)) {
 					// std::cerr << "This exists, but as a file: [" << sofar << "]" << (size_t)st.st_ino << endl;
@@ -198,24 +221,24 @@ bool cFilesystemUtils::CreateDirTree(const std::string & dir, bool only_below) {
 				}
 			}
 		#elif defined(OS_TYPE_WINDOWS)
-			DWORD dwAttrib = GetFileAttributesA(sofar.c_str());
+			DWORD dwAttrib = GetFileAttributesA(sofarS.c_str());
 			bool exists = (dwAttrib != INVALID_FILE_ATTRIBUTES && (dwAttrib & FILE_ATTRIBUTE_DIRECTORY));
 		#else
 			#error "Do not know how to compile this for your platform."
 		#endif
 
 		if (!exists) {
-			if (dbg) cout << "mkdir ["<<sofar<<"]"<<endl;
+			if (dbg) cout << "mkdir ["<<sofarS<<"]"<<endl;
 			#if defined(OS_TYPE_POSIX)
-				bool ok = 0==  mkdir(sofar.c_str(), 0700); // ***
+				bool ok = 0==  mkdir(sofarS.c_str(), 0700); // ***
 			#elif defined(OS_TYPE_WINDOWS)
-				bool ok = (bool) CreateDirectoryA(sofar.c_str(), NULL); // TODO use -W() after conversion to unicode UTF16
+				bool ok = (bool) CreateDirectoryA(sofarS.c_str(), NULL); // TODO use -W() after conversion to unicode UTF16
 			#else
 				#error "Do not know how to compile this for your platform."
 			#endif
 			if (!ok) return false;
 		}
-		sofar += cFilesystemUtils::GetDirSeparator();
+		sofarS += dirchS;
 	}
 	return true;
 }
@@ -244,11 +267,15 @@ void cDebugScopeGuard::Assign(const string &chan, const int level, const string
 
 cLogger::cLogger() :
 mStream(NULL),
+mStreamBrokenDebug(NULL),
+mIsBroken(true), // before constructor finishes
 mLevel(85),
 mThread2Number_Biggest(0) // the CURRENT biggest value (no thread yet in map)
 {
 	mStream = & std::cout;
+	mStreamBrokenDebug = & std::cerr;
 	Thread2Number( std::this_thread::get_id() ); // convert current id to short number, useful to reserve a number so that main thread is usually called 1
+	mIsBroken=false; // ok, constr. succeeded, so string is not broken now
 }
 
 cLogger::~cLogger() {
@@ -259,12 +286,28 @@ cLogger::~cLogger() {
 	}
 }
 
+void cLogger::SetStreamBroken() {
+	SetStreamBroken("(no additional details about this problem)");
+}
+
+void cLogger::SetStreamBroken(const std::string &msg) {
+	if (!mIsBroken) { // if not already marked as broken
+		std::cerr << OT_CODE_STAMP << "WARNING: due to debug stream problem ("<<msg<<") - switching back to fallback stream (e.g. cerr)" << std::endl;
+		if (mStreamBrokenDebug == nullptr) {
+			std::cerr << OT_CODE_STAMP << " ERROR: in addition, while reporting this problem, mStreamBrokenDebug stream is NULL." << std::endl;
+		} else {
+			(*mStreamBrokenDebug) << OT_CODE_STAMP << "WARNING: due to debug stream problem ("<<msg<<") - switching back to fallback stream (e.g. cerr)" << std::endl;
+		}
+		mIsBroken = true;
+	}
+}
+
 std::ostream & cLogger::write_stream(int level) {
 	return write_stream(level,"");
 }
 
 std::ostream & cLogger::write_stream(int level, const std::string & channel ) {
-	if ((level >= mLevel) && (mStream)) {
+	if ((level >= mLevel) && (mStream)) { // TODO now disabling mStream also disables writting to any channel
 		ostream & output = SelectOutput(level,channel);
 		output << icon(level) << ' ';
 		std::thread::id this_id = std::this_thread::get_id();
@@ -278,33 +321,76 @@ std::string cLogger::GetLogBaseDir() const {
 	return "log";
 }
 
-void cLogger::OpenNewChannel(const std::string & channel) {
-	size_t last_split = channel.find_last_of(cFilesystemUtils::GetDirSeparator());
-	// log/test/aaa
+void cLogger::OpenNewChannel(const std::string & channel) noexcept {
+	try {
+		std::cerr<<"openning channel for channel="<<channel<<endl;
+		OpenNewChannel_(channel);
+	}
+	catch (const std::exception &except) {
+		SetStreamBroken(OT_CODE_STAMP + " Got exception when opening debug channel: " + ToStr(except.what()));
+	}
+	catch (...) {
+		SetStreamBroken(OT_CODE_STAMP + " Got not-standard exception when opening debug channel.");
+	}
+}
+
+void cLogger::OpenNewChannel_(const std::string & channel) { // channel=="net/sleep"
+	size_t last_split = channel.find_last_of(cFilesystemUtils::GetDirSeparatorInter());
+
+	string fname_system; // the full file name in system format
+
+	if (last_split==string::npos) { // The channel name has no directory, eg channel=="test"
+		string dir = GetLogBaseDir();
+		string basefile = channel + ".log";
+		string fname = dir + cFilesystemUtils::GetDirSeparatorInter() + basefile;
+		fname_system = cFilesystemUtils::FileInternalToSystem(fname); // <-
+	}
+	else { // there is a directory eg channel=="net/sleep"
+		// net/sleep 
 		//    ^----- last_split	
-	string dir = GetLogBaseDir() + cFilesystemUtils::GetDirSeparator() + channel.substr(0, last_split);
+		string dir = GetLogBaseDir() + cFilesystemUtils::GetDirSeparatorInter() + channel.substr(0, last_split);
 		string basefile = channel.substr(last_split+1) + ".log";
-	string fname = dir + cFilesystemUtils::GetDirSeparator() + cFilesystemUtils::GetDirSeparator() + basefile;
-	_dbg1("Starting debug to channel file: " + fname + " in directory ["+dir+"]");
+		string fname = dir + cFilesystemUtils::GetDirSeparatorInter() + basefile;
+		fname_system = cFilesystemUtils::FileInternalToSystem(fname); // <-
 		bool dirok = cFilesystemUtils::CreateDirTree(dir);
-	if (!dirok) { const string msg = "In logger failed to open directory (" + dir +")."; _erro(msg); throw std::runtime_error(msg); }
-	std::ofstream * thefile = new std::ofstream( fname.c_str() );
-	*thefile << "====== (Log opened: " << fname << ") ======" << endl;
-	mChannels.insert( std::pair<string,std::ofstream*>(channel , thefile ) );
+		if (!dirok) { string err = "In logger failed to open directory (" + dir +") for channel (" + channel +")"; throw std::runtime_error(err); }
 	}
 
-std::ostream & cLogger::SelectOutput(int level, const std::string & channel) {
+	std::ofstream * thefile = new std::ofstream( fname_system.c_str() ); // file system
+	*thefile << "====== Log opened: " << fname_system << " (in " << ((void*)thefile) << ") ======" << endl;
+    	cerr << "====== Log opened: " << fname_system << " (in " << ((void*)thefile) << ") ======" << endl;
+	mChannels.insert( std::pair<string,std::ofstream*>(channel , thefile ) ); // <- created the channel mapping
+}
+
+std::ostream & cLogger::SelectOutput(int level, const std::string & channel) noexcept {
+	try {
+		if (mIsBroken) return *mStreamBrokenDebug;
 		if (channel=="") return *mStream;
+
 		auto obj = mChannels.find(channel);
-	if (obj == mChannels.end()) { // new channel
-		OpenNewChannel(channel);
-		return SelectOutput(level,channel);
+		if (obj == mChannels.end()) { // not found - need to make new channel
+			OpenNewChannel(channel); // <- create channel
+			obj = mChannels.find(channel); // find again
+			if (obj == mChannels.end()) { // still not found! something is wrong
+				SetStreamBroken( OT_CODE_STAMP + " WARNING: can not get stream for channel="+ToStr(channel)+" level="+ToStr(channel) );
+				return *mStreamBrokenDebug;
 			}
-	else { // existing
-		return * obj->second;
 		}
+		auto the_stream_ptr = obj->second;
+		ASRT(the_stream_ptr);
+		return *the_stream_ptr; // <--- RETURN
+	} 
+	catch (std::exception &except) { 
+		SetStreamBroken( OT_CODE_STAMP + " Got exception: " + ToStr(except.what()) );
+		return *mStreamBrokenDebug;
+	}
+	catch (...) {
+		SetStreamBroken( OT_CODE_STAMP + " Got not-standard exception.");
+		return *mStreamBrokenDebug;
 	}
 
+	// dead code
+}
 
 void cLogger::setOutStreamFile(const string &fname) { // switch to using this file
 	_mark("WILL SWITCH DEBUG NOW to file: " << fname);

contrib/otshell_utils/utils.hpp

@@ -185,6 +185,7 @@ const char* DbgShortenCodeFileName(const char *s); ///< Returns a pointer to som
 /*** 
 @brief Class to write debug into. Used it by calling the debug macros _dbg1(...) _info(...) _erro(...) etc, NOT directly!
 @author rfree (maintainer) 
+@thread this class is NOT thread safe and must used only by one thread at once (use it via ot_debug_macros like _info macro they do proper locking)
 */
 class cLogger {
 	public:
@@ -201,15 +202,21 @@ class cLogger {
 		std::string endline() const; ///< returns string to be written at end of message
 
 	protected:
+		void SetStreamBroken(); ///< call in case of internal error in logger (e.g. can not open a file)
+		void SetStreamBroken(const std::string &msg); ///< same but with error message
+
 		unique_ptr<std::ofstream> mOutfile;
 		std::ostream * mStream; ///< pointing only! can point to our own mOutfile, or maye to global null stream
+		std::ostream * mStreamBrokenDebug; ///< pointing only! this is a pointer to some stream that should be used when normal debugging is broken eg std::cerr
+		bool mIsBroken; ///< is the debugging system broken (this should be set when internal problems occur and should cause fallback to std::cerr)
 
 		std::map< std::string , std::ofstream * > mChannels; // the ofstream objects are owned by this class
 
 		int mLevel; ///< current debug level
 
-		std::ostream & SelectOutput(int level, const std::string & channel);
-		void OpenNewChannel(const std::string & channel);
+		std::ostream & SelectOutput(int level, const std::string & channel) noexcept; ///< returns a proper stream for this level and channel (always usable string)
+		void OpenNewChannel(const std::string & channel) noexcept; ///< tries to prepare this channel. does NOT guarantee to created mChannels[] entry!
+		void OpenNewChannel_(const std::string & channel);  ///< internal function, will throw in case of problems
 		std::string GetLogBaseDir() const;
 
 		std::map< std::thread::id , int > mThread2Number; // change long thread IDs into a short nice number to show
@@ -360,7 +367,10 @@ eSubjectType String2SubjectType(const string & type);
 class cFilesystemUtils { // if we do not want to use boost in given project (or we could optionally write boost here later)
 	public:
 		static bool CreateDirTree(const std::string & dir, bool only_below=false);
-		static char GetDirSeparator(); // eg '/' or '\'
+		static char GetDirSeparatorSys(); /// < eg '/' or '\'
+		static char GetDirSeparatorInter(); /// < internal is '/'
+		static string FileInternalToSystem(const std::string &name); ///< converts from internal file name string to system file name string
+		static string FileSystemToInternal(const std::string &name); ///< converts from system file name string to internal file name string
 };
 
 

src/common/util.cpp

@@ -326,7 +326,7 @@ std::string get_nix_version_display_string()
     std::string config_folder;
 
 #ifdef WIN32
-    config_folder = get_special_folder_path(CSIDL_APPDATA, true) + "/" + CRYPTONOTE_NAME;
+    config_folder = get_special_folder_path(CSIDL_APPDATA, true) + "\\" + CRYPTONOTE_NAME;
 #else
     std::string pathRet;
     char* pszHome = getenv("HOME");

src/daemon/daemon.cpp

@@ -125,7 +125,8 @@ int main(int argc, char* argv[])
   LOG_PRINT_L0("Starting...");
   
   nOT::nUtils::cFilesystemUtils::CreateDirTree("log/dr-monero/net/");
-	// _warn_c("log/test","Starting program"); // TODO
+	_warn_c("test","Starting program (a test message)");
+	_warn_c("main/program","Starting program");
 
   TRY_ENTRY();  
 
@@ -319,6 +320,7 @@ int main(int argc, char* argv[])
   ccore.set_cryptonote_protocol(NULL);
   cprotocol.set_p2p_endpoint(NULL);
 
+  epee::net_utils::data_logger::get_instance().kill_instance();
   LOG_PRINT("Node stopped.", LOG_LEVEL_0);
   return 0;
 

src/p2p/connection_basic.cpp

@@ -272,6 +272,7 @@ void connection_basic::logger_handle_net_write(size_t size) {
 }
 
 double connection_basic::get_sleep_time(size_t cb) {
+	CRITICAL_REGION_LOCAL(epee::net_utils::network_throttle_manager::network_throttle_manager::m_lock_get_global_throttle_out);
     auto t = network_throttle_manager::get_global_throttle_out().get_sleep_time(cb);
     return t;
 }

src/p2p/data_logger.cpp

@@ -1,4 +1,5 @@
 #include "data_logger.hpp"
+#include <stdexcept>
 
 #include <boost/chrono.hpp>
 #include <boost/filesystem.hpp>
@@ -9,25 +10,25 @@ namespace epee
 {
 namespace net_utils
 {
-	data_logger &data_logger::get_instance()
-	{
-		static data_logger instance;
-		return instance;
+	data_logger &data_logger::get_instance() {
+		std::call_once(m_singleton, 
+			[] { 
+				_info_c("dbg/data","Creating singleton of data_logger");
+				if (m_state != data_logger_state::state_before_init) { _erro_c("dbg/data","Internal error in singleton"); throw std::runtime_error("data_logger singleton"); }
+				m_state = data_logger_state::state_during_init;
+				m_obj.reset(new data_logger());
+				m_state = data_logger_state::state_ready_to_use;
+			}	
+		);
+		return * m_obj;
 	}
 	
-	data_logger::data_logger()
-	{
-		//create timer
-		std::shared_ptr<std::thread> logger_thread(new std::thread([&]()
-		{
-			while (true)
-			{
-				std::this_thread::sleep_for(std::chrono::seconds(1));
-				saveToFile();
-			}
-		}));
-		logger_thread->detach();
+	data_logger::data_logger() {
+		_warn_c("dbg/data","Starting data logger (for graphs data)");
+		if (m_state != data_logger_state::state_during_init) { _erro_c("dbg/data","Singleton ctor state"); throw std::runtime_error("data_logger ctor state"); }
+		std::lock_guard<std::mutex> lock(mMutex); // lock
 		
+		// prepare all the files for given data channels:
 		mFilesMap["peers"] = data_logger::fileData("log/dr-monero/peers.data");
 		mFilesMap["download"] = data_logger::fileData("log/dr-monero/net/in-all.data");
 		mFilesMap["upload"] = data_logger::fileData("log/dr-monero/net/out-all.data");
@@ -44,25 +45,80 @@ namespace net_utils
 		mFilesMap["peers_limit"].mLimitFile = true;
 		mFilesMap["download_limit"].mLimitFile = true;
 		mFilesMap["upload_limit"].mLimitFile = true;
+
+		// do NOT modify mFilesMap below this point, since there is no locking for this used (yet)
+
+		_note_c("dbg/data","Creating thread for data logger"); // create timer thread
+		m_thread_maybe_running=true;
+		std::shared_ptr<std::thread> logger_thread(new std::thread([&]() {
+			_note_c("dbg/data","Inside thread for data logger");
+			while (m_state == data_logger_state::state_during_init) { // wait for creation to be done (in other thread, in singleton) before actually running
+				std::this_thread::sleep_for(std::chrono::seconds(1));
+			}
+			_note_c("dbg/data","Inside thread for data logger - going into main loop");
+			while (m_state == data_logger_state::state_ready_to_use) { // run as long as we are not closing the single object
+				std::this_thread::sleep_for(std::chrono::seconds(1));
+				saveToFile(); // save all the pending data
+			}
+			_note_c("dbg/data","Inside thread for data logger - done the main loop");
+			m_thread_maybe_running=false;
+		}));
+		logger_thread->detach();
+		_info_c("dbg/data","Data logger constructed");
 	}
 
-	void data_logger::add_data(std::string filename, unsigned int data)
+	data_logger::~data_logger() {
+		_note_c("dbg/data","Destructor of the data logger");
 		{
-		if (mFilesMap.find(filename) == mFilesMap.end())
-			return; // TODO: exception
+			std::lock_guard<std::mutex> lock(mMutex);
+			m_state = data_logger_state::state_dying;
+		}
+		_info_c("dbg/data","State was set to dying");
+		while(m_thread_maybe_running) { // wait for the thread to exit
+			std::this_thread::sleep_for(std::chrono::seconds(1));
+			_info_c("dbg/data","Waiting for background thread to exit");
+		}
+		_info_c("dbg/data","Thread exited");
+	}
 
+	void data_logger::kill_instance() { 
+		m_state = m_state = data_logger_state::state_dying;
+		m_obj.reset();
+	}
 	
-		nOT::nUtils::cFilesystemUtils::CreateDirTree("log/dr-monero/net/");
+	void data_logger::add_data(std::string filename, unsigned int data) {
+		std::lock_guard<std::mutex> lock(mMutex);
+		if (m_state != data_logger_state::state_ready_to_use) { _info_c("dbg/data","Data logger is not ready, returning."); return; }
 
-		std::lock_guard<std::mutex> lock(mSaveMutex);
-		if (mFilesMap[filename].mLimitFile)
+		if (mFilesMap.find(filename) == mFilesMap.end()) { // no such file/counter
+			_erro_c("dbg/data","Trying to use not opened data file filename="<<filename);
+			_erro_c("dbg/data","Disabling saving of graphs due to error");
+			m_save_graph=false; // <--- disabling saving graphs
+			return;
+		}
+		
+		if (mFilesMap[filename].mLimitFile) { // this holds a number (that is not additive) - e.g. the limit setting
 			mFilesMap[filename].mDataToSave = data;
-		else
-			mFilesMap[filename].mDataToSave += data;
+		} else {
+			mFilesMap[filename].mDataToSave += data; // this holds a number that should be sum of all accumulated samples
+		}
 	}
 
-	double data_logger::fileData::get_current_time()
+	void data_logger::saveToFile() {
+		_dbg2_c("dbg/data","saving to files");
+		std::lock_guard<std::mutex> lock(mMutex);
+		if (m_state != data_logger_state::state_ready_to_use) { _info_c("dbg/data","Data logger is not ready, returning."); return; }
+		nOT::nUtils::cFilesystemUtils::CreateDirTree("log/dr-monero/net/");
+		for (auto &element : mFilesMap)
 		{
+			element.second.save();
+			if (!element.second.mLimitFile) element.second.mDataToSave = 0;
+		}
+	}
+
+	// the inner class:
+	
+	double data_logger::fileData::get_current_time() {
 		using namespace boost::chrono;
 		auto point = steady_clock::now();
 		auto time_from_epoh = point.time_since_epoch();
@@ -71,33 +127,28 @@ namespace net_utils
 		return ms_f / 1000.;
 	}
 	
-	data_logger::fileData::fileData(std::string pFile)
-	{
+	data_logger::fileData::fileData(std::string pFile) {
+		_dbg3_c("dbg/data","opening data file named pFile="<<pFile<<" for this="<<this);
 		mFile = std::make_shared<std::ofstream> (pFile);
+		_dbg1_c("dbg/data","opened data file named pFile="<<pFile<<" in mFile="<<mFile<<" for this="<<this);
 		mPath = pFile;
 	}
 	
-	void data_logger::fileData::save()
-	{
-		if (!data_logger::m_save_graph)
-			return;
+	void data_logger::fileData::save() {
+		if (!data_logger::m_save_graph) return; // <--- disabled
+		_dbg2_c("dbg/data","saving to the file now, mFile="<<mFile);
 		mFile->open(mPath, std::ios::app);
 		*mFile << static_cast<int>(get_current_time()) << " " << mDataToSave << std::endl;
 		mFile->close();
 	}
 	
-	void data_logger::saveToFile()
-	{
-		std::lock_guard<std::mutex> lock(mSaveMutex);
-		for (auto &element : mFilesMap)
-		{
-			element.second.save();
-			if (!element.second.mLimitFile)
-				element.second.mDataToSave = 0;
-		}
-	}
 	
-std::atomic<bool> data_logger::m_save_graph(false);
+data_logger_state data_logger::m_state(data_logger_state::state_before_init); ///< (static) state of the singleton object
+std::atomic<bool> data_logger::m_save_graph(false); // (static)
+std::atomic<bool> data_logger::m_thread_maybe_running(false); // (static)
+std::once_flag data_logger::m_singleton; // (static)
+std::unique_ptr<data_logger> data_logger::m_obj; // (static)
 
 } // namespace
 } // namespace
+

src/p2p/data_logger.hpp

@@ -14,33 +14,59 @@ namespace epee
 namespace net_utils
 {
 
+enum class data_logger_state { state_before_init, state_during_init, state_ready_to_use, state_dying };
+	
+/***
+@note: use it ONLY via singleton! It will be spawned then, and will auto destruct on program exit.
+@note: do call ::kill_instance() before exiting main, at end of main. But before make sure no one else (e.g. no other threads) will try to use this/singleton
+@note: it is not allowed to use this class from code "runnig before or after main", e.g. from ctors of static objects, because of static-creation-order races
+@note: on creation (e.g. from singleton), it spawns a thread that saves all data in background
+*/
 	class data_logger {
 		public:
-			static data_logger &get_instance();
-			data_logger(const data_logger &ob) = delete;
-			data_logger(data_logger &&ob) = delete;
-			void add_data(std::string filename, unsigned int data);
-			static std::atomic<bool> m_save_graph;
+			static data_logger &get_instance(); ///< singleton
+			static void kill_instance(); ///< call this before ending main to allow more gracefull shutdown of the main singleton and it's background thread
+			~data_logger(); ///< destr, will be called when singleton is killed when global m_obj dies. will kill theads etc
+
 		private:
-			data_logger();
-			class fileData
-			{
+			data_logger(); ///< constructor is private, use only via singleton get_instance
+
 		public:
-					fileData(){}
+			data_logger(const data_logger &ob) = delete; // use only one per program
+			data_logger(data_logger &&ob) = delete;
+			data_logger & operator=(const data_logger&) = delete;
+			data_logger & operator=(data_logger&&) = delete;
+
+			void add_data(std::string filename, unsigned int data); ///< use this to append data here. Use it only the singleton. It locks itself.
+
+			static std::atomic<bool> m_save_graph; ///< global setting flag, should we save all the data or not (can disable logging graphs data)
+
+		private:
+			static std::once_flag m_singleton; ///< to guarantee singleton creates the object exactly once
+			static data_logger_state m_state; ///< state of the singleton object
+			static std::atomic<bool> m_thread_maybe_running; ///< is the background thread (more or less) running, or is it fully finished
+			static std::unique_ptr<data_logger> m_obj; ///< the singleton object. Only use it via get_instance(). Can be killed by kill_instance()
+
+			/***
+			* one graph/file with data
+			*/
+			class fileData {
+				public:
+					fileData() = default;
 					fileData(const fileData &ob) = delete;
 					fileData(std::string pFile);
 					
 					std::shared_ptr<std::ofstream> mFile;
-					long int mDataToSave = 0;
+					long int mDataToSave = 0; ///< sum of the data (in current interval, will be counted from 0 on next interval)
 					static double get_current_time();
 					void save();
 					std::string mPath;
-					bool mLimitFile = false;
+					bool mLimitFile = false; ///< this holds a number (that is not additive) - e.g. the limit setting
 			};
 			
 			std::map<std::string, fileData> mFilesMap;
-			std::mutex mSaveMutex;
-			void saveToFile();
+			std::mutex mMutex;
+			void saveToFile(); ///< write data to the target files. do not use this directly
 	};
 	
 } // namespace

src/p2p/network_throttle.cpp

@@ -78,7 +78,6 @@ int network_throttle_manager::xxx;
 // ================================================================================================
 // methods:
 i_network_throttle & network_throttle_manager::get_global_throttle_in() { 
-
 	std::call_once(m_once_get_global_throttle_in, [] { m_obj_get_global_throttle_in.reset(new network_throttle("in/all","<<< global-IN",10)); }	);
 	return * m_obj_get_global_throttle_in;
 }

tests/core_proxy/core_proxy.cpp

@@ -62,6 +62,8 @@ using namespace crypto;
 
 BOOST_CLASS_VERSION(nodetool::node_server<cryptonote::t_cryptonote_protocol_handler<tests::proxy_core> >, 1);
 
+unsigned int epee::g_test_dbg_lock_sleep = 0;
+
 int main(int argc, char* argv[])
 {
 
@@ -148,6 +150,7 @@ int main(int argc, char* argv[])
 
 
   LOG_PRINT("Node stopped.", LOG_LEVEL_0);
+  epee::net_utils::data_logger::get_instance().kill_instance();
   return 0;
 
   CATCH_ENTRY_L0("main", 1);

tests/core_proxy/core_proxy.h

@@ -82,5 +82,7 @@ namespace tests
     bool find_blockchain_supplement(const std::list<crypto::hash>& qblock_ids, cryptonote::NOTIFY_RESPONSE_CHAIN_ENTRY::request& resp){return true;}
     bool handle_get_objects(cryptonote::NOTIFY_REQUEST_GET_OBJECTS::request& arg, cryptonote::NOTIFY_RESPONSE_GET_OBJECTS::request& rsp, cryptonote::cryptonote_connection_context& context){return true;}
     cryptonote::blockchain_storage &get_blockchain_storage() { throw std::runtime_error("Called invalid member function: please never call get_blockchain_storage on the TESTING class proxy_core."); }
+    bool get_test_drop_download() {return true;}
+    bool get_test_drop_download_height() {return true;}
   };
 }

tests/core_tests/CMakeLists.txt

@@ -60,6 +60,8 @@ add_executable(coretests
 target_link_libraries(coretests
   LINK_PRIVATE
     cryptonote_core
+    p2p
+    ${Boost_CHRONO_LIBRARY}
     ${Boost_FILESYSTEM_LIBRARY}
     ${Boost_SYSTEM_LIBRARY}
     ${CMAKE_THREAD_LIBS_INIT}

tests/core_tests/chaingen_main.cpp

@@ -44,6 +44,8 @@ namespace
   const command_line::arg_descriptor<bool>        arg_test_transactions           = {"test_transactions", ""};
 }
 
+unsigned int epee::g_test_dbg_lock_sleep = 0;
+
 int main(int argc, char* argv[])
 {
   TRY_ENTRY();

tests/functional_tests/main.cpp

@@ -55,6 +55,8 @@ namespace
   const command_line::arg_descriptor<size_t> arg_test_repeat_count = {"test_repeat_count", "", 1};
 }
 
+unsigned int epee::g_test_dbg_lock_sleep = 0;
+
 int main(int argc, char* argv[])
 {
   TRY_ENTRY();

tests/net_load_tests/CMakeLists.txt

@@ -39,6 +39,7 @@ target_link_libraries(net_load_tests_clt
   LINK_PRIVATE
 	otshell_utils
 	p2p
+	cryptonote_core
     ${GTEST_MAIN_LIBRARIES}
     ${Boost_CHRONO_LIBRARY}
     ${Boost_DATE_TIME_LIBRARY}
@@ -60,6 +61,7 @@ target_link_libraries(net_load_tests_srv
   LINK_PRIVATE
 	otshell_utils
 	p2p
+	cryptonote_core
     ${GTEST_MAIN_LIBRARIES}
     ${Boost_CHRONO_LIBRARY}
     ${Boost_DATE_TIME_LIBRARY}

tests/net_load_tests/clt.cpp

@@ -623,6 +623,8 @@ TEST_F(net_load_test_clt, permament_open_and_close_and_connections_closed_by_ser
   ASSERT_EQ(RESERVED_CONN_CNT, m_tcp_server.get_config_object().get_connections_count());
 }
 
+unsigned int epee::g_test_dbg_lock_sleep = 0;
+
 int main(int argc, char** argv)
 {
   epee::debug::get_set_enable_assert(true, false);
@@ -631,5 +633,6 @@ int main(int argc, char** argv)
   epee::log_space::log_singletone::add_logger(LOGGER_CONSOLE, NULL, NULL);
 
   ::testing::InitGoogleTest(&argc, argv);
+  epee::net_utils::data_logger::get_instance().kill_instance();
   return RUN_ALL_TESTS();
 }

tests/net_load_tests/srv.cpp

@@ -213,6 +213,8 @@ namespace
   };
 }
 
+unsigned int epee::g_test_dbg_lock_sleep = 0;
+
 int main(int argc, char** argv)
 {
   //set up logging options
@@ -232,6 +234,6 @@ int main(int argc, char** argv)
 
   if (!tcp_server.run_server(thread_count, true))
     return 2;
-
+  epee::net_utils::data_logger::get_instance().kill_instance();
   return 0;
 }

tests/performance_tests/main.cpp

@@ -42,6 +42,8 @@
 #include "generate_key_image_helper.h"
 #include "is_out_to_acc.h"
 
+unsigned int epee::g_test_dbg_lock_sleep = 0;
+
 int main(int argc, char** argv)
 {
   set_process_affinity(1);

tests/unit_tests/main.cpp

@@ -32,6 +32,8 @@
 
 #include "include_base_utils.h"
 
+unsigned int epee::g_test_dbg_lock_sleep = 0;
+
 int main(int argc, char** argv)
 {
   epee::debug::get_set_enable_assert(true, false);