[OLOG-57] do not log to file if path is empty (#84)

* [OLOG-57] do not log to file if path is empty

* release notes

Author: Barthelemy

doc/releaseNotes.md

@@ -126,3 +126,6 @@ This file describes the main feature changes for each InfoLogger released versio
 
 ## v2.5.0 - 17/06/2022
 - added InfoLogger::filterDiscardSetFile(), to allow saving to local file the messages that would be discarded with filterDiscard(...) settings.
+
+## v2.5.1 - 13/07/2022
+- do not try to log to file if the path is empty.

src/InfoLogger.cxx

@@ -1191,9 +1191,8 @@ void InfoLogger::filterDiscardLevel(int excludeLevel) {
 int InfoLogger::filterDiscardSetFile(const char *path, unsigned long rotateMaxBytes, unsigned int rotateMaxFiles, unsigned int rotateNow) {
   mPimpl->filterDiscardFileEnabled = false;
   int err = mPimpl->filterDiscardFile.setLogFile(path, rotateMaxBytes, rotateMaxFiles, rotateNow);
-  if (!err) {
+  if (!err && path != nullptr && path[0] != '\0') {
     mPimpl->filterDiscardFileEnabled = true;
-    //mPimpl->filterDiscardFile.setOutputFormat(SimpleLog::FormatOption::ShowMessage);
   }
   return err;
 }