OLSRd commons library
Copyright (c) 2004-2011 the olsr.org team
Cleaned up and extracted into this form by Henning Rogge in 2011

The OLSRd commons library is a collection of helper functions
that are used through the whole OSLRd for list/tree handling,
string management and other things.

=================================
    OLSRd commons netaddr API
=================================

The netaddr API provides an unified handling of different addresses.
It supports IPv4, IPv6, MAC-48 and EUI-64 addresses, both with and
without prefix lengths and offers API calls for conversion from or to
binary or text representation.

Each netaddr object stores its own address type, so the address type
doesn't need to be handled in the users code. 

In addition to this it provides an union object for all four kinds of
sockaddr structs (no support for unix sockets at the moment), which
allows to interface with os network function without casting between
data types (which produce an error on some modern gcc variants).

It also provides an inet_ntop() and inet_pton() function (for IPv4 and
IPv6) for win32.

For a full list of helper functions, see the netaddr.h file.



======================================
    OLSRd commons netaddr overview
======================================

1) netaddr string conversion
2) netaddr binary conversion
3) netaddr_socket functions
4) netaddr compare functions



1) netaddr string conversion
****************************

netaddr_to_string() and netaddr_from_string() are the two main
conversion functions between string and netaddr format. Both of
them automatically detect the address format and the optional
prefix length.

netaddr_to_prefixstring() is a special function that allows the
user to force the output of a prefix length, even if it has the
maximum length (10.0.0.0/32 instead of just 10.0.0.0).



2) netaddr binary conversion
****************************

netaddr_to_binary() and netaddr_from_binary() work similar than
the string variants. netaddr_to_binary() ignores the prefix length
to allow the user to store it into the right data field itself.
netaddr_from_binary() initialize the prefix length with the
maximum value.

netaddr_to_autobuf() is similar to netaddr_to_binary() but just
adds the binary address to an autobuf.



3) netaddr_socket functions
***************************

netaddr_socket_init() initialize a netaddr_socket with a netaddr
address and a port number.
netaddr_socket_get_port() returns the port number set in the
netaddr_socket object.

netaddr_socket_to_string() converts a netaddr_socket into a
string representation.

netaddr_from_socket() extracts the address part of the object
into a netaddr.



4) netaddr compare functions
****************************

netaddr_cmp() and netaddr_socket_cmp() are inline comparator
functions for netaddr and netaddr_socket objects.

netaddr_is_in_subnet() and netaddr_binary_is_in_subnet() check
if a netaddr/binary address is inside the subnet defined by
another netaddr and its prefix length.

netaddr_avlcmp() is a comparator for the avl API for netaddr
objects.