Avoid Serial output mangling with RTOS.

src/RedirectablePrint.cpp

@@ -18,6 +18,12 @@ NoopPrint noopPrint;
 #if HAS_WIFI || HAS_ETHERNET
 extern Syslog syslog;
 #endif
+void RedirectablePrint::rpInit()
+{
+#ifdef HAS_FREE_RTOS
+    inDebugPrint = xSemaphoreCreateMutexStatic(&this->_MutexStorageSpace);
+#endif
+}
 
 void RedirectablePrint::setDestination(Print *_dest)
 {
@@ -66,9 +72,12 @@ size_t RedirectablePrint::log(const char *logLevel, const char *format, ...)
         return 0;
     }
     size_t r = 0;
-
+#ifdef HAS_FREE_RTOS
+    if (inDebugPrint != nullptr && xSemaphoreTake(inDebugPrint, portMAX_DELAY) == pdTRUE) {
+#else
     if (!inDebugPrint) {
         inDebugPrint = true;
+#endif
 
         va_list arg;
         va_start(arg, format);
@@ -141,7 +150,11 @@ size_t RedirectablePrint::log(const char *logLevel, const char *format, ...)
         va_end(arg);
 
         isContinuationMessage = !hasNewline;
+#ifdef HAS_FREE_RTOS
+        xSemaphoreGive(inDebugPrint);
+#else
         inDebugPrint = false;
+#endif
     }
 
     return r;

src/RedirectablePrint.h

@@ -1,5 +1,6 @@
 #pragma once
 
+#include "../freertosinc.h"
 #include <Print.h>
 #include <stdarg.h>
 #include <string>
@@ -16,14 +17,19 @@ class RedirectablePrint : public Print
     /// Used to allow multiple logDebug messages to appear on a single log line
     bool isContinuationMessage = false;
 
+#ifdef HAS_FREE_RTOS
+    SemaphoreHandle_t inDebugPrint = nullptr;
+    StaticSemaphore_t _MutexStorageSpace;
+#else
     volatile bool inDebugPrint = false;
-
+#endif
   public:
     explicit RedirectablePrint(Print *_dest) : dest(_dest) {}
 
     /**
      * Set a new destination
      */
+    void rpInit();
     void setDestination(Print *dest);
 
     virtual size_t write(uint8_t c);
@@ -54,4 +60,4 @@ class NoopPrint : public Print
 /**
  * A printer that doesn't go anywhere
  */
-extern NoopPrint noopPrint;
+extern NoopPrint noopPrint;

src/SerialConsole.cpp

@@ -12,6 +12,7 @@ SerialConsole *console;
 void consoleInit()
 {
     new SerialConsole(); // Must be dynamically allocated because we are now inheriting from thread
+    DEBUG_PORT.rpInit(); // Simply sets up semaphore
 }
 
 void consolePrintf(const char *format, ...)