PiFace Digital2 Raspberry Pi ctrl.kernel module mcp23017

//utilisse le driver mcp23017
//  /boot/config.txt pour i2C  dtoverlay=mcp23017,addr=0x20,gpiopin=24
// pour spi PiFace2 dtoverlay=mcp23s17:s17-spi0-0-present=1
#include <iostream>
#include <fstream>
#include <string>
#include <unistd.h>

#define GPIO_DIR "/sys/class/gpio"
#define GPIO_ADDR 496 //Addresse base pour le driver mcp23017 496 , le fin 511

using namespace std;
class mcp23017{
    public:
    mcp23017 ();
    ~mcp23017();
    void gpioSet(int gpio, int value);
    int gpioRead(int gpio);
    void gpioUnexport();//Delete All PORTS GPIO dans /sys/class/gpio
    enum  {INPUT,OUTPUT};
    enum  {ON,OFF};

    private:
    void configureMcp23017();//Configure PORTA,B Axisat 8IN & 8OUT
    void gpioExport(int gpio);//Cree gpioNNN ,miroir PORTA,B dans sys/class/gpio
    void gpioDirection(int gpio, int direction); //0 INPUT 1 OUTPUT
    bool error(bool ok,string dir);
    int read;
};
//----------------------------------------------------------------------
mcp23017::mcp23017(){read=0;configureMcp23017();}//Constructeur
//mcp23017::~mcp23017(){gpioUnexport();}//Destructeur de la classe efface PORTs
mcp23017::~mcp23017(){}//Destructeur de la classe efface PORTs
void mcp23017::configureMcp23017(){//Configure PORTA,B Axisat 8IN & 8OUT
    size_t offset(0);
    do{
        gpioExport(GPIO_ADDR+offset);//Cree miroir PORTA,B dans sys/class/gpio
        //usleep(5000);
        sleep(1);
        gpioDirection ( GPIO_ADDR+offset ,offset <8 ?OUTPUT:INPUT);//configure PORTA,B
    }while (offset++ <15);
}
void mcp23017::gpioExport(int gpio){//Cree gpioNNN ,miroir PORTA,B dans sys/class/gpio
        std::fstream buf;
        string dir(GPIO_DIR"/export");
        buf.open (dir,std::fstream::out);
        if (!error(!buf.fail()," EXPORT "+dir+to_string(gpio)) ){return ;}
        buf<<gpio;
        buf.close();
}
void mcp23017::gpioDirection(int gpio, int direction){//0 INPUT 1 OUTPUT
        std::fstream buf;
        string dir(GPIO_DIR+string("/gpio")+to_string(gpio)+string("/direction"));
        buf.open (dir,std::fstream::out);
        if (!error(!buf.fail()," DIR "+dir) ){return ;}
        buf<<string ((direction==OUTPUT) ? "out":"in");
        buf.close();
}
void mcp23017::gpioSet(int gpio, int value){
        std::fstream buf;
        string dir(GPIO_DIR+string("/gpio")+to_string(gpio)+string("/value"));
        buf.open (dir, std::fstream::out);
        if (!error(!buf.fail()," SET "+dir) ){return ;}
        buf<<value;
        buf.close();
}
int mcp23017::gpioRead(int gpio){
        std::fstream buf;
        string dir(GPIO_DIR+string("/gpio")+to_string(gpio)+string("/value"));
        buf.open (dir, std::fstream::in );
        if (!error(!buf.fail()," READ "+dir) ){return -1;}
        buf>>read;
        buf.close();
        return read;
}
void mcp23017::gpioUnexport(){//Delete All PORTS GPIO dans /sys/class/gpio
        std::fstream buf;
        int offset(0);
        string dir(GPIO_DIR"/unexport");
        do{
            buf.open ( dir,std::fstream::out);// Overture /sys/class/gpio/unexport
            if (!error(!buf.fail()," DEL "+dir+to_string(GPIO_ADDR+offset)) ){return ;}
            buf<<(to_string(GPIO_ADDR+offset));//Ecrire dans unexport le Num à effacer gpioNNN
            buf.close();
        }while ((offset++)<15);
}
bool mcp23017::error(bool ok,string dir){
    if (ok) {cout<<endl<<" OPEN OK "<<dir<<endl;return true;}//OK
    else {cout<<endl<<" Error OPEN!!! "<<dir<<endl;return false;}
}
//----------------------------------------------------------------------
//----------------------------------------------------------------------

int main (){
    mcp23017 mcp;//Configure 1 MCP23017 pour Axisat...cree sys/class/gpio

    for (int offset=15;offset >=0;offset--){    //Test IN & OUT
        if (offset>7){//Read
            cout<<mcp.gpioRead(GPIO_ADDR+offset)<<" = IN"<<offset<<endl;
        }else{ mcp.gpioSet(GPIO_ADDR+offset,1);}//Sortie =1
    }

    mcp.gpioUnexport();//Efface ports crees aver export dans sys/class/gpio
        return 0;
}