Redirect ESP log messages into virtual debug console

include/ESPLog.h

@@ -0,0 +1,27 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+#pragma once
+
+#include <stdarg.h>
+#include <TaskSchedulerDeclarations.h>
+#include <mutex>
+
+#define BUFFER_SIZE 500
+
+class ESPLogClass {
+public:
+    ESPLogClass();
+    void init(Scheduler& scheduler);
+    int vprintf(const char *format, va_list ap);
+
+private:
+    void loop();
+
+    Task _loopTask;
+
+    uint8_t _buffer[BUFFER_SIZE];
+    uint16_t _buff_pos = 0;
+    std::mutex _lock;
+};
+
+extern ESPLogClass ESPLog;
+

src/ESPLog.cpp

@@ -0,0 +1,63 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2022-2024 Thomas Basler and others
+ */
+#include "ESPLog.h"
+#include "MessageOutput.h"
+
+#include <Arduino.h>
+
+ESPLogClass ESPLog;
+
+namespace {
+
+static int extern "C" wrap_vprintf(const char *format, va_list ap)
+{
+    return ESPLog.vprintf(format, ap);
+}
+
+}; // namespace
+
+ESPLogClass::ESPLogClass()
+    : _loopTask(TASK_IMMEDIATE, TASK_FOREVER, std::bind(&ESPLogClass::loop, this))
+{
+}
+
+void ESPLogClass::init(Scheduler& scheduler)
+{
+    scheduler.addTask(_loopTask);
+    _loopTask.enable();
+    esp_log_set_vprintf(wrap_vprintf);
+}
+
+void ESPLogClass::loop()
+{
+    _lock.lock();
+    int front = 0;
+    int used = _buff_pos;
+    while (used > front) {
+        _lock.unlock();
+        MessageOutput.write(&_buffer[front], used);
+        _lock.lock();
+
+        front = used;
+        used = _buff_pos;
+    };
+    _buff_pos = 0;
+    _lock.unlock();
+}
+
+int ESPLogClass::vprintf(const char *format, va_list ap)
+{
+    std::lock_guard<std::mutex> lock(_lock);
+    char *buf = reinterpret_cast<char*>(&_buffer[_buff_pos]);
+    size_t remain = sizeof(_buffer) - _buff_pos;
+
+    if (remain == 0) {
+        return 0;
+    }
+
+    int printed = vsnprintf(buf, remain, format, ap);
+    _buff_pos += printed;
+     return printed;
+}

src/main.cpp

@@ -8,6 +8,7 @@
 #include "InverterSettings.h"
 #include "Led_Single.h"
 #include "MessageOutput.h"
+#include "ESPLog.h"
 #include "MqttHandleDtu.h"
 #include "MqttHandleHass.h"
 #include "MqttHandleInverter.h"
@@ -51,6 +52,7 @@ void setup()
         yield();
 #endif
     MessageOutput.init(scheduler);
+    ESPLog.init(scheduler);
     MessageOutput.println();
     MessageOutput.println("Starting OpenDTU");