Fixed a mistake in my last commit and added file name checks when creating files.

meteoio/Config.cc

@@ -186,14 +186,8 @@ void Config::parseFile(const std::string& filename)
 {
 	std::ifstream fin; //Input file streams
 
-	if (!IOUtils::validFileName(filename)) {
-		throw InvalidFileNameException(filename,AT);
-	}
-
-	//Check whether file exists
-	if (!IOUtils::fileExists(filename)) {
-		throw FileNotFoundException(filename, AT);
-	}
+	if (!IOUtils::validFileAndPath(filename)) throw InvalidFileNameException(filename,AT);
+	if (!IOUtils::fileExists(filename)) throw FileNotFoundException(filename, AT);
 
 	//Open file
 	fin.open (filename.c_str(), ifstream::in);
@@ -361,9 +355,8 @@ std::string Config::clean_import_path(const std::string& in_path) const
 
 void Config::write(const std::string& filename) const
 {
-
-	std::ofstream fout;
-	fout.open(filename.c_str());
+	if (!IOUtils::validFileAndPath(filename)) throw InvalidFileNameException(filename,AT);
+	std::ofstream fout(filename.c_str(), ios::out);
 	if (fout.fail())
 		throw FileAccessException(filename, AT);
 

meteoio/FileUtils.cc

@@ -48,7 +48,7 @@ void copy_file(const std::string& src, const std::string& dest)
 	std::ifstream fin(src.c_str(), std::ios::binary);
 	if (fin.fail()) throw FileAccessException(src, AT);
 
-	if (!IOUtils::validFileName(dest)) throw InvalidFileNameException(dest, AT);
+	if (!IOUtils::validFileAndPath(dest)) throw InvalidFileNameException(dest, AT);
 	std::ofstream fout(dest.c_str(), std::ios::binary);
 	if (fout.fail()) {
 		fin.close();
@@ -80,6 +80,7 @@ std::string cleanPath(std::string in_path, const bool& resolve)
 	#else //POSIX
 		std::replace(in_path.begin(), in_path.end(), '\\', '/');
 		
+		errno = 0;
 		char *real_path = realpath(in_path.c_str(), NULL); //POSIX 2008
 		if (real_path!=NULL) {
 			const std::string tmp(real_path);
@@ -136,8 +137,7 @@ std::string getFilename(const std::string& path)
 		return path;
 }
 
-//this checks for path+file
-bool validFileName(const std::string& filename)
+bool validFileAndPath(const std::string& filename)
 {
 #if defined _WIN32 || defined __MINGW32__ || defined __CYGWIN__
 	const size_t startpos = filename.find_first_not_of(" \t\n"); // Find the first character position after excluding leading blank spaces
@@ -153,7 +153,6 @@ bool validFileName(const std::string& filename)
 	return true;
 }
 
-
 bool isAbsolutePath(const std::string& in_path)
 {
 #if defined _WIN32 || defined __MINGW32__ || defined __CYGWIN__

meteoio/FileUtils.h

@@ -48,7 +48,7 @@ namespace IOUtils {
 	
 	std::list<std::string> readDirectory(const std::string& path, const std::string& pattern="");
 
-	bool validFileName(const std::string& filename);
+	bool validFileAndPath(const std::string& filename);
 
 	bool fileExists(const std::string& filename);
 

meteoio/InterpolationAlgorithms.cc

@@ -952,7 +952,7 @@ double USERInterpolation::getQualityRating(const Date& i_date, const MeteoData::
 	param = in_param;
 	filename = getGridFileName();
 
-	if (!IOUtils::validFileName(filename)) {
+	if (!IOUtils::validFileAndPath(filename)) {
 		cerr << "[E] Invalid grid filename for "+algo+" interpolation algorithm: " << filename << "\n";
 		return 0.0;
 	}

meteoio/meteoFilters/ProcessingBlock.cc

@@ -205,6 +205,7 @@ std::string ProcessingBlock::getName() const {
 void ProcessingBlock::readCorrections(const std::string& filter, const std::string& filename, const char& c_type, const double& init, std::vector<double> &corrections)
 {
 	if (!IOUtils::fileExists(filename)) throw FileAccessException(filename, AT); //prevent invalid filenames
+	errno = 0;
 	std::ifstream fin(filename.c_str(), std::ifstream::in);
 	if (fin.fail()) {
 		std::ostringstream ss;

meteoio/plugins/A3DIO.cc

@@ -730,6 +730,7 @@ int A3DIO::create1DFile(const std::vector< std::vector<MeteoData> >& data)
 		const size_t size = data[ii].size();
 		if(size>0) {
 			const std::string filename = tmp_path+"/meteo1D_"+data[ii][0].meta.getStationID()+".txt";
+			if (!IOUtils::validFileAndPath(filename)) throw InvalidFileNameException(filename,AT);
 			std::ofstream file(filename.c_str(), std::ios::out | std::ios::trunc);
 			if(!file) {
 				throw FileAccessException("[E] Can not open file "+filename, AT);
@@ -821,7 +822,7 @@ void A3DIO::open2DFile(const std::vector< std::vector<MeteoData> >& data,
 	out << year;
 
 	const std::string filename = fileprefix+out.str()+".txt";
-
+	if (!IOUtils::validFileAndPath(filename)) throw InvalidFileNameException(filename,AT);
 	file.open(filename.c_str(), ios::out | ios::trunc);
 	if(!file) {
 		throw FileAccessException("Can not create file "+filename, AT);

meteoio/plugins/ALPUG.cc

@@ -135,6 +135,7 @@ void ALPUG::readMetaData()
 	const string filename = cfg.get("METAFILE", "Input");
 	const string metafile = inpath + "/" + filename;
 	if (!IOUtils::fileExists(metafile)) throw FileAccessException(metafile, AT); //prevent invalid filenames
+	errno = 0;
 	std::ifstream fin(metafile.c_str(), std::ifstream::in);
 	if (fin.fail()) {
 		ostringstream ss;
@@ -341,6 +342,7 @@ void ALPUG::readMetoFile(const size_t& station_index, const Date& dateStart, con
 		
 		const string file_and_path = inpath + "/" + filename;
 		if (!IOUtils::fileExists(file_and_path)) throw FileAccessException(file_and_path, AT); //prevent invalid filenames
+		errno = 0;
 		std::ifstream fin(file_and_path.c_str(), ios::in|ios::binary); //ascii does end of line translation, which messes up the pointer code
 		if (fin.fail()) 
 			throw FileAccessException("Could not open \'" + file_and_path +"\'. Possible reason: " + strerror(errno) + "\n", AT);

meteoio/plugins/ARCIO.cc

@@ -170,10 +170,11 @@ void ARCIO::read2DGrid_internal(Grid2DObject& grid_out, const std::string& full_
 	std::string line;
 	std::map<std::string, std::string> header; // A map to save key value pairs of the file header
 
-	if (!IOUtils::validFileName(full_name)) throw InvalidFileNameException(full_name, AT);
+	if (!IOUtils::validFileAndPath(full_name)) throw InvalidFileNameException(full_name, AT);
 	if (!IOUtils::fileExists(full_name)) throw FileNotFoundException(full_name, AT);
 
 	fin.clear();
+	errno = 0;
 	fin.open (full_name.c_str(), ifstream::in);
 	if (fin.fail()) {
 		ostringstream ss;
@@ -329,8 +330,9 @@ void ARCIO::readPOI(std::vector<Coords>&)
 void ARCIO::write2DGrid(const Grid2DObject& grid_in, const std::string& name)
 {
 	const std::string full_name = grid2dpath_out+"/"+name;
-	if (!IOUtils::fileExists(full_name)) throw FileAccessException(full_name, AT); //prevent invalid filenames
-	fout.open(full_name.c_str());
+	if (!IOUtils::validFileAndPath(full_name)) throw InvalidFileNameException(full_name,AT);
+	errno = 0;
+	fout.open(full_name.c_str(), ios::out);
 	if (fout.fail()) {
 		ostringstream ss;
 		ss << "Error opening file \"" << full_name << "\", possible reason: " << strerror(errno);

meteoio/plugins/CNRMIO.cc

@@ -929,6 +929,7 @@ void CNRMIO::write2DGrid_internal(const Grid2DObject& grid_in, const std::string
 
 		ncpp::start_definitions(filename, ncid);
 	} else {
+		if (!IOUtils::validFileAndPath(filename)) throw InvalidFileNameException(filename,AT);
 		ncpp::create_file(filename, NC_CLASSIC_MODEL, ncid);
 		ncpp::add_attribute(ncid, NC_GLOBAL, "Conventions", "CF-1.3");
 

meteoio/plugins/GRIBIO.cc

@@ -435,6 +435,7 @@ void GRIBIO::read2DGrid(Grid2DObject& grid_out, const std::string& i_name)
 {
 	const std::string filename = grid2dpath_in+"/"+i_name;
 	if (!IOUtils::fileExists(filename)) throw FileAccessException(filename, AT); //prevent invalid filenames
+	errno = 0;
 	fp = fopen(filename.c_str(),"r");
 	if(fp==NULL) {
 		ostringstream ss;
@@ -463,6 +464,7 @@ void GRIBIO::read2DGrid(Grid2DObject& grid_out, const std::string& i_name)
 void GRIBIO::indexFile(const std::string& filename)
 {
 	if (!IOUtils::fileExists(filename)) throw FileAccessException(filename, AT); //prevent invalid filenames
+	errno = 0;
 	fp = fopen(filename.c_str(),"r");
 	if(fp==NULL) {
 		ostringstream ss;

meteoio/plugins/GeotopIO.cc

@@ -134,7 +134,9 @@ void GeotopIO::writeMeteoData( const std::vector<std::vector<MeteoData> >& vecMe
 	}
 
 	//write the meta data file _meteo.txt
-	fout.open(string(path + "/_meteo.txt").c_str());
+	const string meteoFile = path + "/_meteo.txt";
+	if (!IOUtils::validFileAndPath(meteoFile)) throw InvalidFileNameException(meteoFile,AT);
+	fout.open(meteoFile.c_str(), ios::out);
 	fout << "/* Automatically generated by MeteoIO */\n\n";
 	fout << "1: double matrix meteo_station{" << vecMeteo.size() << ",13}\n";
 	for (size_t ii = 0; ii < vecMeteo.size(); ii++) {
@@ -162,7 +164,8 @@ void GeotopIO::writeMeteoData( const std::vector<std::vector<MeteoData> >& vecMe
 		ss.fill('0');
 		ss << path << "/" << "_meteo" << setw(4) << (ii + 1) << ".txt";
 
-		fout.open(ss.str().c_str());
+		if (!IOUtils::validFileAndPath(ss.str())) throw InvalidFileNameException(ss.str(),AT);
+		fout.open(ss.str().c_str(), ios::out);
 		if (fout.fail())
 			throw FileAccessException(ss.str().c_str(), AT);
 
@@ -220,10 +223,10 @@ void GeotopIO::readStationData(const Date&, std::vector<StationData>& vecMeta) {
 void GeotopIO::readMeteoData(const Date& dateStart, const Date& dateEnd,
                              std::vector<std::vector<MeteoData> >& vecMeteo, const size_t& /*stationindex*/) {
 	vecMeteo.clear();
-	string line, filename, path, prefix;
+	string line;
 
-	cfg.getValue("METEOPATH", "Input", path);
-	cfg.getValue("METEOPREFIX", "Input", prefix);
+	const string path = cfg.get("METEOPATH", "Input");
+	const string prefix = cfg.get("METEOPREFIX", "Input");
 
 	//read geotop.inpts to find out how many stations exist
 	//at what locations they are and what column headers to use
@@ -246,13 +249,9 @@ void GeotopIO::readMeteoData(const Date& dateStart, const Date& dateEnd,
 		ss.fill('0');
 		ss << path << "/" << prefix << setw(4) << (ii + 1) << ".txt";
 
-		filename = ss.str();
-
-		if (!IOUtils::validFileName(filename))
-			throw InvalidFileNameException(filename, AT);
-
-		if (!IOUtils::fileExists(filename))
-			throw FileNotFoundException(filename, AT);
+		const string filename = ss.str();
+		if (!IOUtils::validFileAndPath(filename)) throw InvalidFileNameException(filename, AT);
+		if (!IOUtils::fileExists(filename)) throw FileNotFoundException(filename, AT);
 
 		fin.clear();
 		fin.open(filename.c_str(), std::ifstream::in);
@@ -404,12 +403,8 @@ void GeotopIO::readMetaData(const std::string& metafile) {
 	std::vector<std::string> tmpvec;
 	unsigned int stationNumber = 1; //Since the stations don't have a name, they will be numbered
 
-	if (!IOUtils::validFileName(metafile)) {
-		throw InvalidFileNameException(metafile, AT);
-	}
-	if (!IOUtils::fileExists(metafile)) {
-		throw FileNotFoundException(metafile, AT);
-	}
+	if (!IOUtils::validFileAndPath(metafile)) throw InvalidFileNameException(metafile, AT);
+	if (!IOUtils::fileExists(metafile)) throw FileNotFoundException(metafile, AT);
 
 	fin.clear();
 	fin.open(metafile.c_str(), std::ifstream::in);

meteoio/plugins/GrassIO.cc

@@ -79,12 +79,8 @@ void GrassIO::read2DGrid(Grid2DObject& grid_out, const std::string& filename)
 	std::string line;
 	std::map<std::string, std::string> header; // A map to save key value pairs of the file header
 
-	if (!IOUtils::validFileName(filename)) {
-		throw InvalidFileNameException(filename, AT);
-	}
-	if (!IOUtils::fileExists(filename)) {
-		throw FileNotFoundException(filename, AT);
-	}
+	if (!IOUtils::validFileAndPath(filename)) throw InvalidFileNameException(filename, AT);
+	if (!IOUtils::fileExists(filename)) throw FileNotFoundException(filename, AT);
 
 	fin.clear();
 	fin.open (filename.c_str(), ifstream::in);
@@ -226,7 +222,8 @@ void GrassIO::readPOI(std::vector<Coords>&)
 
 void GrassIO::write2DGrid(const Grid2DObject& grid_in, const std::string& name)
 {
-	fout.open(name.c_str());
+	if (!IOUtils::validFileAndPath(name)) throw InvalidFileNameException(name, AT);
+	fout.open(name.c_str(), ios::out);
 	if (fout.fail()) {
 		throw FileAccessException(name, AT);
 	}

meteoio/plugins/NetCDFIO.cc

@@ -534,6 +534,7 @@ void NetCDFIO::write2DGrid_internal(Grid2DObject grid_in, const std::string& fil
 
 		ncpp::start_definitions(filename, ncid);
 	} else {
+		if (!IOUtils::validFileAndPath(filename)) throw InvalidFileNameException(filename, AT);
 		ncpp::create_file(filename, NC_CLASSIC_MODEL, ncid);
 		ncpp::add_attribute(ncid, NC_GLOBAL, "Conventions", "CF-1.3");
 		create_variable = create_dimensions = true;

meteoio/plugins/PGMIO.cc

@@ -103,14 +103,11 @@ void PGMIO::read2DGrid_internal(Grid2DObject& grid_out, const std::string& full_
 	std::vector<std::string> tmpvec;
 	std::string line;
 
-	if (!IOUtils::validFileName(full_name)) {
-		throw InvalidFileNameException(full_name, AT);
-	}
-	if (!IOUtils::fileExists(full_name)) {
-		throw FileNotFoundException(full_name, AT);
-	}
+	if (!IOUtils::validFileAndPath(full_name)) throw InvalidFileNameException(full_name, AT);
+	if (!IOUtils::fileExists(full_name)) throw FileNotFoundException(full_name, AT);
 
 	fin.clear();
+	errno = 0;
 	fin.open (full_name.c_str(), ifstream::in);
 	if (fin.fail()) {
 		ostringstream ss;
@@ -246,7 +243,9 @@ void PGMIO::write2DGrid(const Grid2DObject& grid_in, const std::string& name)
 {
 	const std::string full_name = grid2dpath_out+"/"+name;
 	const unsigned int nr_colors = 256;
-	fout.open(full_name.c_str());
+	if (!IOUtils::validFileAndPath(full_name)) throw InvalidFileNameException(full_name, AT);
+	errno = 0;
+	fout.open(full_name.c_str(), ios::out);
 	if (fout.fail()) {
 		ostringstream ss;
 		ss << "Error opening file \"" << full_name << "\", possible reason: " << strerror(errno);

meteoio/plugins/PNGIO.cc

@@ -318,9 +318,7 @@ Grid2DObject PNGIO::scaleGrid(const Grid2DObject& grid_in)
 void PNGIO::setFile(const std::string& filename, png_structp& png_ptr, png_infop& info_ptr, const size_t &width, const size_t &height)
 {
 	// Open file for writing (binary mode)
-	if (!IOUtils::validFileName(filename)) {
-		throw InvalidFileNameException(filename, AT);
-	}
+	if (!IOUtils::validFileAndPath(filename)) throw InvalidFileNameException(filename, AT);
 	errno=0;
 	fp = fopen(filename.c_str(), "wb");
 	if (fp == NULL) {
@@ -674,8 +672,8 @@ void PNGIO::writeWorldFile(const Grid2DObject& grid_in, const std::string& filen
 	world_ref.setProj(coordout, coordoutparam);
 	world_ref.moveByXY(.5*cellsize, (double(grid_in.getNy())+.5)*cellsize); //moving to center of upper left cell
 
-	std::ofstream fout;
-	fout.open(world_file.c_str());
+	if (!IOUtils::validFileAndPath(world_file)) throw InvalidFileNameException(world_file, AT);
+	std::ofstream fout(world_file.c_str(), ios::out);
 	if (fout.fail()) {
 		throw FileAccessException(world_file, AT);
 	}

meteoio/plugins/SMETIO.cc

@@ -166,7 +166,7 @@ void SMETIO::parseInputOutputSection()
 			const string extension = IOUtils::getExtension(filename);
 			const std::string file_and_path = (!extension.empty())? inpath+"/"+filename : inpath+"/"+filename+dflt_extension;
 
-			if (!IOUtils::validFileName(file_and_path)) //Check whether filename is valid
+			if (!IOUtils::validFileAndPath(file_and_path)) //Check whether filename is valid
 				throw InvalidFileNameException(file_and_path, AT);
 			vecFiles.push_back(file_and_path);
 			vec_smet_reader.push_back(smet::SMETReader(file_and_path));
@@ -455,7 +455,7 @@ void SMETIO::writeMeteoData(const std::vector< std::vector<MeteoData> >& vecMete
 		}
 
 		const string filename = outpath + "/" + sd.stationID + ".smet";
-		if (!IOUtils::validFileName(filename)) //Check whether filename is valid
+		if (!IOUtils::validFileAndPath(filename)) //Check whether filename is valid
 			throw InvalidFileNameException(filename, AT);
 
 		//2. check which meteo parameter fields are actually in use

meteoio/plugins/SNIO.cc

@@ -223,18 +223,8 @@ void SNIO::readStationData(const Date&, std::vector<StationData>& vecStation)
 
 bool SNIO::readStationMetaData(const std::string& metafile, const std::string& stationID, StationData& sd)
 {
-	if (!IOUtils::validFileName(metafile)) {
-		std::ostringstream ss;
-		ss << "\"" << metafile << "\" is not a valid file name. Please check your METAFILE key!";
-		throw InvalidFileNameException(metafile, AT);
-	}
-
-	if (!IOUtils::fileExists(metafile)) {
-		std::ostringstream ss;
-		ss << "File \"" << metafile << "\" does not exist. Please check your METAFILE key!";
-		throw FileNotFoundException(ss.str(), AT);
-	}
-
+	if (!IOUtils::validFileAndPath(metafile)) throw InvalidFileNameException("\"" + metafile + "\" is not a valid file name. Please check your METAFILE key!", AT);
+	if (!IOUtils::fileExists(metafile)) throw FileNotFoundException( "File \"" + metafile + "\" does not exist. Please check your METAFILE key!", AT);
 
 	fin.clear();
 	fin.open (metafile.c_str(), std::ifstream::in);
@@ -280,10 +270,8 @@ std::string SNIO::getStationID(const std::string& filename)
 	 * This function will return the station name as retrieved from
 	 * the first line of a SNIO formatted meteo file
 	 */
-	if ( !IOUtils::validFileName(filename) )
-		throw InvalidFileNameException(filename, AT);
-	if ( !IOUtils::fileExists(filename) )
-		throw FileNotFoundException(filename, AT);
+	if ( !IOUtils::validFileAndPath(filename) ) throw InvalidFileNameException(filename, AT);
+	if ( !IOUtils::fileExists(filename) ) throw FileNotFoundException(filename, AT);
 
 	fin.clear();
 	fin.open (filename.c_str(), std::ifstream::in);
@@ -359,7 +347,7 @@ void SNIO::readMetaData()
 		const std::string file_and_path = (extension!="")? inpath+"/"+filename : inpath+"/"+filename+dflt_extension;
 		const string station_id = getStationID(file_and_path);
 
-		if (!IOUtils::validFileName(file_and_path)) //Check whether filename is valid
+		if (!IOUtils::validFileAndPath(file_and_path)) //Check whether filename is valid
 			throw InvalidFileNameException(file_and_path, AT);
 
 		StationData sd(Coords(), station_id);
@@ -399,10 +387,8 @@ void SNIO::readMeteoData(const Date& dateStart, const Date& dateEnd,
 	for (size_t ii=0; ii<vecAllStations.size(); ii++){
 		const std::string file_with_path = vecFilenames[ii];
 
-		if ( !IOUtils::validFileName(file_with_path) )
-			throw InvalidFileNameException(file_with_path, AT);
-		if ( !IOUtils::fileExists(file_with_path) )
-			throw FileNotFoundException(file_with_path, AT);
+		if ( !IOUtils::validFileAndPath(file_with_path) ) throw InvalidFileNameException(file_with_path, AT);
+		if ( !IOUtils::fileExists(file_with_path) ) throw FileNotFoundException(file_with_path, AT);
 
 		fin.clear();
 		fin.open (file_with_path.c_str(), std::ifstream::in);
@@ -613,6 +599,7 @@ void SNIO::writeMeteoData(const std::vector< std::vector<MeteoData> >& vecMeteo,
 			std::string station_id = vecMeteo[ii].front().meta.getStationID();
 			if (station_id.empty()) station_id = "UNKNOWN";
 			const std::string output_name = outpath + "/" + station_id + ".inp";
+			if (!IOUtils::validFileAndPath(output_name)) throw InvalidFileNameException(output_name,AT);
 			if( !IOUtils::fileExists(output_name) ) {
 				fout.open(output_name.c_str());
 				writeStationHeader(vecMeteo[ii], station_id);

meteoio/plugins/libsmet.cc

@@ -112,6 +112,22 @@ bool SMETCommon::fileExists(const std::string& filename)
 }
 #endif
 
+bool SMETCommon::validFileAndPath(const std::string& filename)
+{
+#if defined _WIN32 || defined __MINGW32__ || defined __CYGWIN__
+	const size_t startpos = filename.find_first_not_of(" \t\n"); // Find the first character position after excluding leading blank spaces
+	const size_t invalid_char = filename.find_first_of("\000*:<>?|"); //find possible invalid characters
+#else
+	const size_t startpos = filename.find_first_not_of(" \t\n"); // Find the first character position after excluding leading blank spaces
+	const size_t invalid_char = filename.find_first_of("\000"); //find possible invalid characters
+#endif
+	
+	if ((startpos!=0) || (invalid_char!=std::string::npos) || (filename==".") || (filename=="..")) {
+		return false;
+	}
+	return true;
+}
+
 double SMETCommon::convert_to_double(const std::string& in_string)
 {
 	char* conversion_end = NULL;
@@ -449,6 +465,8 @@ bool SMETWriter::valid_header()
 
 void SMETWriter::write(const std::vector<std::string>& vec_timestamp, const std::vector<double>& data)
 {
+	if (!SMETCommon::validFileAndPath(filename)) throw SMETException("Invalid file name \""+filename+"\"", AT);
+	errno = 0;
 	fout.open(filename.c_str(), ios::binary);
 	if (fout.fail()) {
 		ostringstream ss;
@@ -495,6 +513,8 @@ void SMETWriter::write(const std::vector<std::string>& vec_timestamp, const std:
 
 void SMETWriter::write(const std::vector<double>& data)
 {
+	if (!SMETCommon::validFileAndPath(filename)) throw SMETException("Invalid file name \""+filename+"\"", AT);
+	errno = 0;
 	fout.open(filename.c_str(), ios::binary);
 	if (fout.fail()) {
 		ostringstream ss;
@@ -609,6 +629,7 @@ void SMETWriter::write_data_line_binary(const std::vector<double>& data)
 
 	if (!file_is_binary){ //open it as binary file
 		fout.close();
+		errno = 0;
 		fout.open(filename.c_str(), ios::out | ios::app | ios::binary); //reopen as binary file
 		if (fout.fail()) {
 			ostringstream ss;
@@ -693,6 +714,7 @@ SMETReader::SMETReader(const std::string& in_fname)
 	std::ifstream fin; //Input file streams
 	fin.clear();
 	if (!SMETCommon::fileExists(filename)) throw SMETException(filename, AT); //prevent invalid filenames
+	errno = 0;
 	fin.open (filename.c_str(), ios::in|ios::binary); //ascii does end of line translation, which messes up the pointer code
 	if (fin.fail()) {
 		ostringstream ss;
@@ -999,6 +1021,7 @@ void SMETReader::read(std::vector<std::string>& vec_timestamp, std::vector<doubl
 	ifstream fin;
 	fin.clear();
 	if (!SMETCommon::fileExists(filename)) throw SMETException(filename, AT); //prevent invalid filenames
+	errno = 0;
 	fin.open (filename.c_str(), ios::in|ios::binary); //ascii mode messes up pointer code on windows (automatic eol translation)
 	if (fin.fail()) {
 		ostringstream ss;
@@ -1049,6 +1072,7 @@ void SMETReader::read(std::vector<double>& vec_data)
 
 	ifstream fin;
 	if (!SMETCommon::fileExists(filename)) throw SMETException(filename, AT); //prevent invalid filenames
+	errno = 0;
 	fin.open (filename.c_str(), mode);
 	if (fin.fail()) {
 		ostringstream ss;

meteoio/plugins/libsmet.h

@@ -63,6 +63,7 @@ class SMETException : public std::exception {
  */
 class SMETCommon {
 	public:
+		static bool validFileAndPath(const std::string& filename);
 		static bool fileExists(const std::string& filename);
 		static double convert_to_double(const std::string& in_string);
 		static int convert_to_int(const std::string& in_string);