IP Address Object (IPADDR)

Example Path: examples/IPADDR-IpAddressObject

FunWithIPADDR - NetBurner IP Address Object Example

Overview

FunWithIPADDR is a C++ demonstration application that showcases the NetBurner IPADDR object functionality. This application demonstrates how to work with IP addresses in a dual-stack (IPv4/IPv6) environment using NetBurner's unified IPADDR object system.

Note

In rare cases in which you want to create an object of a specific type, you can create objects as IPADDR4 or IPADDR6. However, we highly recommend using IPADDR for all your IP addresses. Note that if you are using a printf() style format specifier, you must use "%hI" instead of "%I" and pass in a IPADDR4 object, otherwise the value displayed will be 0.0.0.0.

What is IPADDR?

The IPADDR object is a C++ class that provides a unified interface for handling both IPv4 and IPv6 addresses without requiring separate code paths. This design enables applications to support both IP versions seamlessly, with the object automatically determining the appropriate operations based on the assigned address type.

Key Features

• Dual-stack support: Single object handles both IPv4 and IPv6 addresses
• Automatic type detection: Member functions automatically call appropriate IPv4 or IPv6 implementations
• Unified printf formatting: Custom I format specifier for easy display
• Null address handling: Built-in methods to check for and set null addresses
• Type-specific objects: Optional IPADDR4 and IPADDR6 for specialized use cases

Application Functionality

The application demonstrates the following IPADDR capabilities:

1. Basic Address Assignment and Display

• Creates IPADDR objects for both IPv4 and IPv6 addresses
• Uses SetFromAscii() to assign addresses from string literals
• Displays addresses using the custom I printf format specifier

2. Member Function Usage

• Demonstrates the print() member function for address output
• Shows how the same function works for both IPv4 and IPv6 addresses

3. Null Address Handling

• Tests for null addresses using IsNull() member function
• Demonstrates setting addresses to null with SetNull()

4. Type-Specific Objects (IPADDR4)

• Shows creation of IPADDR4 objects for IPv4-specific needs
• Demonstrates the required hI format specifier for IPADDR4 objects

5. IPv6 Static Methods (Conditional)

• When IPv6 is enabled, shows usage of AsciiToIp6() static method

6. Live Web Display

• Serves a small web page that shows the same IPADDR results in a browser, in addition to the serial output
• A <!--CPPCALL ShowIpResults --> tag in html/index.html hands the HTTP socket to the ShowIpResults() function, which formats each address into the page with fdprintf using the same I / hI specifiers
• Demonstrates that I works with any printf variant, including one that writes to a network socket
• The page uses a self-contained stylesheet (plain CSS, no framework or CDN) so it serves entirely from on-device flash

Code Examples

Creating and Using IPADDR Objects

// IPv4 address
IPADDR ipaddrIPv4;
ipaddrIPv4.SetFromAscii("192.168.1.4");
printf("IPv4 Address: %I\r\n", ipaddrIPv4);
 
// IPv6 address
IPADDR ipaddrIPv6;
ipaddrIPv6.SetFromAscii("2001:0db8:85a3:0000:0000:8a2e:0370:0006");
printf("IPv6 Address: %I\r\n", ipaddrIPv6);

Null Address Checking

if (ipaddrIPv4.IsNull())
    printf("Address is null\r\n");
else
    printf("Address: %I\r\n", ipaddrIPv4);

Using Type-Specific Objects

IPADDR4 ipaddrIPADDR4;
ipaddrIPADDR4.SetFromAscii("192.168.4.4");
// Note: Must use %hI for IPADDR4 objects
printf("IPADDR4: %hI\r\n", ipaddrIPADDR4);

Important Notes

Printf Format Specifiers

• Use I for general IPADDR objects
• Use hI for IPADDR4 objects (failure to do so will display 0.0.0.0)
• The I format works with all printf variants (printf, sprintf, fdprintf, etc.)

Best Practices

• Use the generic IPADDR class for most applications
• Only use IPADDR4 or IPADDR6 when type-specific functionality is required
• Always check for null addresses when necessary
• The unified approach reduces code complexity and maintenance

Application Flow

1. Initialization: Sets up the NetBurner system and network stack
2. Network Wait: Waits up to 5 seconds for active network connectivity
3. HTTP Start: Initializes the HTTP server
4. IPADDR Demonstrations: Runs through various IPADDR usage examples
5. Main Loop: Enters an infinite loop with 1-second delays

Build Requirements

• NetBurner development environment
• NetBurner RTOS (nbrtos.h)
• HTTP support (http.h)
• Standard C++ compiler with NetBurner extensions

System Features Used

• System diagnostics (enabled for debugging)
• Network stack initialization
• HTTP server functionality
• Custom printf formatting