Error messages: Fix Logger exceptions.

Refs #6070

icinga-app/icinga.cpp

@@ -429,7 +429,16 @@ int Main(void)
 #endif /* _WIN32 */
 
 	if (g_AppParams.count("log-level")) {
-		LogSeverity logLevel = Logger::StringToSeverity(g_AppParams["log-level"].as<std::string>());
+		String severity = g_AppParams["log-level"].as<std::string>();
+
+		LogSeverity logLevel = LogInformation;
+		try {
+			logLevel = Logger::StringToSeverity(severity);
+		} catch (std::exception&) {
+			/* use the default */
+			Log(LogWarning, "icinga", "Invalid log level set. Using default 'information'.");
+		}
+
 		Logger::SetConsoleLogSeverity(logLevel);
 	}
 

lib/base/logger.cpp

@@ -123,8 +123,15 @@ LogSeverity Logger::GetMinSeverity(void) const
 	String severity = GetSeverity();
 	if (severity.IsEmpty())
 		return LogInformation;
-	else
+	else {
-		return Logger::StringToSeverity(severity);
+		LogSeverity ls = LogInformation;
+
+		try {
+			ls = Logger::StringToSeverity(severity);
+		} catch (std::exception&) { /* use the default level */ }
+
+		return ls;
+	}
 }
 
 /**
@@ -146,6 +153,7 @@ String Logger::SeverityToString(LogSeverity severity)
 		case LogCritical:
 			return "critical";
 		default:
+			Log(LogCritical, "Logger", "Invalid severity.");
 			BOOST_THROW_EXCEPTION(std::invalid_argument("Invalid severity."));
 	}
 }
@@ -167,9 +175,11 @@ LogSeverity Logger::StringToSeverity(const String& severity)
 		return LogWarning;
 	else if (severity == "critical")
 		return LogCritical;
-	else
+	else {
+		Log(LogCritical, "Logger", "Invalid severity: '" + severity + "'.");
 		BOOST_THROW_EXCEPTION(std::invalid_argument("Invalid severity: " + severity));
 	}
+}
 
 void Logger::DisableConsoleLog(void)
 {

lib/base/streamlogger.cpp

@@ -114,7 +114,12 @@ void StreamLogger::ProcessLogEntry(std::ostream& stream, bool tty, const LogEntr
 		}
 	}
 
+	try {
 		stream << Logger::SeverityToString(entry.Severity);
+	} catch (std::exception&) {
+		/* bail early */
+		return;
+	}
 
 	if (tty)
 		stream << "\x1b[0m"; // clear colors