Passing HardwareSerial and SoftwareSerial as a Class Property

Question

I wish to know if there is a way to use a single property Serial0 to hold a HardwareSerial or a SoftwareSerial or other class instances supporting basic methods such as available(), read() and write(), in order to make a CustomSerial Class (polymorphism?).

class CustomSerial{
    <GenericSerial??> Serial0;
    char c;
    void read(void){
        c=Serial0.read();
    }
};

The calls should be:

CustomSerial SerialCus;
int n=SerialCus.available();
char c=SerialCus.read();
SerialCus.write(c);

What should I use as GenericSerial class, or what should be the proper use? I tried the Stream class (as the answer pointed), but for some reason the functionality is not preserved (it writes unknown characters). Should indeed Stream be the generic class I need for this?

Answer 1

A base type for Arduino hardware serial classes, SoftwareSerial and other software serial classes and some other Arduino classes is Stream (reference). Stream.h on GitHub

class CustomSerial {

private:
  Stream &stream;

public:
  CustomSerial(Stream &_stream) : stream(_stream) {}

  int read() {
    return stream.read();
  }

  int available() {
    return stream.available();
  }

  int peek() {
    return stream.peek();
  }

  void write(byte b) {
    stream.write(b);
  }

};

SoftwareSerial Serial0(10, 11);
CustomSerial SerialCus(Serial0);

void setup() {
}

void loop(){
  if (SerialCus.available()) {
    char c = SerialCus.read();
    SerialCus.write(c);
  }
}