ip6.h

It support IPv4 and IPv6 unicast and multicast and contains a trivial sender and a trivial receiver

#ifndef IP6_H
#define IP6_H

extern unsigned int ip6_scan(const char *src,char *ip);
extern unsigned int ip6_fmt(char *dest,const char *ip);

extern unsigned int ip6_scan_flat(const char *src,char *);
extern unsigned int ip6_fmt_flat(char *dest,const char *);

/*
 ip6 address syntax: (h = hex digit), no leading '0' required
   1. hhhh:hhhh:hhhh:hhhh:hhhh:hhhh:hhhh:hhhh
   2. any number of 0000 may be abbreviated as "::", but only once
 flat ip6 address syntax:
   hhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh
 */

#define IP6_FMT 40

static const unsigned char V4mappedprefix[12]={0,0,0,0,0,0,0,0,0,0,0xff,0xff};
static const unsigned char V6loopback[16]={0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1};
static const unsigned char V6any[16]={0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};

#define ip6_isv4mapped(ip) (byte_equal(ip,12,V4mappedprefix))

static const char ip4loopback[4] = {127,0,0,1};

#endif