IPAddress.h

/*
 IPAddress.h - Base class that provides IPAddress
 Copyright (c) 2011 Adrian McEwen.  All right reserved.

 This library is free software; you can redistribute it and/or
 modify it under the terms of the GNU Lesser General Public
 License as published by the Free Software Foundation; either
 version 2.1 of the License, or (at your option) any later version.

 This library is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 Lesser General Public License for more details.

 You should have received a copy of the GNU Lesser General Public
 License along with this library; if not, write to the Free Software
 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#ifndef IPAddress_h
#define IPAddress_h

#include <stdint.h>
#include <WString.h>
#include <Printable.h>

// A class to make it easier to handle and pass around IP addresses

class IPAddress: public Printable {
    private:
        union {
                uint8_t bytes[4];  // IPv4 address
                uint32_t dword;
        } _address;

        // Access the raw byte array containing the address.  Because this returns a pointer
        // to the internal structure rather than a copy of the address this function should only
        // be used when you know that the usage of the returned uint8_t* will be transient and not
        // stored.
        uint8_t* raw_address() {
            return _address.bytes;
        }

    public:
        // Constructors
        IPAddress();
        IPAddress(uint8_t first_octet, uint8_t second_octet, uint8_t third_octet, uint8_t fourth_octet);
        IPAddress(uint32_t address);
        IPAddress(const uint8_t *address);

        bool fromString(const char *address);
        bool fromString(const String &address) { return fromString(address.c_str()); }

        // Overloaded cast operator to allow IPAddress objects to be used where a pointer
        // to a four-byte uint8_t array is expected
        operator uint32_t() const {
            return _address.dword;
        }
        bool operator==(const IPAddress& addr) const {
            return _address.dword == addr._address.dword;
        }
        bool operator==(uint32_t addr) const {
            return _address.dword == addr;
        }
        bool operator==(const uint8_t* addr) const;

        // Overloaded index operator to allow getting and setting individual octets of the address
        uint8_t operator[](int index) const {
            return _address.bytes[index];
        }
        uint8_t& operator[](int index) {
            return _address.bytes[index];
        }

        // Overloaded copy operators to allow initialisation of IPAddress objects from other types
        IPAddress& operator=(const uint8_t *address);
        IPAddress& operator=(uint32_t address);

        virtual size_t printTo(Print& p) const;
        String toString();

        friend class EthernetClass;
        friend class UDP;
        friend class Client;
        friend class Server;
        friend class DhcpClass;
        friend class DNSClient;
};

extern const IPAddress INADDR_NONE;

#endif