WIP: Refactor logging facility. log to file with filename related to date

host/esp-t-sim7000g/src/main.cpp

@@ -83,17 +83,20 @@ int vprintf_into_sd(const char *szFormat, va_list args)
 	// write evaluated format string into buffer
 	int ret = vsnprintf(log_print_buffer, sizeof(log_print_buffer), logstring.c_str(), args);
 
+	String date = rtc.getDate();
+	String filename = "/log_" + date + ".txt";
+
 	// output is now in buffer. write to file.
 	if (ret >= 0) {
-		if (!SD.exists("/log.txt")) {
-			File writeLog = SD.open("/log.txt", FILE_WRITE);
+		if (!SD.exists(filename)) {
+			File writeLog = SD.open(filename, FILE_WRITE);
 			if (!writeLog)
-				Serial.println("Couldn't open spiffs_log.txt");
+				Serial.println("Couldn't open " + filename + " for writing");
 			delay(50);
 			writeLog.close();
 		}
 
-		File logFile = SD.open("/log.txt", FILE_APPEND);
+		File logFile = SD.open(filename, FILE_APPEND);
 
 		// debug output
 		vprintf(logstring.c_str(), args);