add some code

main/system_info.h

@@ -0,0 +1,21 @@
+#ifndef _SYSTEM_INFO_H_
+#define _SYSTEM_INFO_H_
+
+#include <string>
+
+#include <esp_err.h>
+#include <freertos/FreeRTOS.h>
+
+class SystemInfo {
+public:
+    static size_t GetFlashSize();
+    static size_t GetMinimumFreeHeapSize();
+    static size_t GetFreeHeapSize();
+    static std::string GetMacAddress();
+    static std::string GetChipModelName();
+    static esp_err_t PrintTaskCpuUsage(TickType_t xTicksToWait);
+    static void PrintTaskList();
+    static void PrintHeapStats();
+};
+
+#endif // _SYSTEM_INFO_H_