/*      $NetBSD: in6_print.c,v 1.1 2014/12/02 19:36:58 christos Exp $   */

/*-
* Copyright (c) 2014 The NetBSD Foundation, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
*    notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
*    notice, this list of conditions and the following disclaimer in the
*    documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>

#include <sys/types.h>
#ifdef _KERNEL
__KERNEL_RCSID(0, "$NetBSD: in6_print.c,v 1.1 2014/12/02 19:36:58 christos Exp $");
#include <sys/systm.h>
#else
__RCSID("$NetBSD: in6_print.c,v 1.1 2014/12/02 19:36:58 christos Exp $");
#include <stdio.h>
#define s6_addr32 __u6_addr.__u6_addr32
static const uint8_t hexdigits[] = "0123456789abcdef";
#endif

#include <netinet/in.h>

int
in6_print(char *buf, size_t len, const struct in6_addr *ia6)
{
       int i;
       char *bp;
       char *cp, *ecp;
       const uint16_t *a;
       const uint8_t *d;
       int dcolon = 0;

       if (IN6_IS_ADDR_V4MAPPED(ia6)) {
               char buf4[INET_ADDRSTRLEN];
               struct in_addr ia = { .s_addr = ia6->s6_addr32[3] };
               in_print(buf4, sizeof(buf4), &ia);
               return snprintf(buf, len, "::ffff:%s", buf4);
       }

#define ADDC(c) do { \
               if (cp >= ecp) {\
                       cp++; \
               } else \
                       *cp++ = (char)(c); \
       } while (/*CONSTCOND*/0)
#define ADDX(v) do { \
               uint8_t n = hexdigits[(v)]; \
               ADDC(n); \
               if (cp == bp && n == '0') \
                       cp--; \
       } while (/*CONSTCOND*/0)

       cp = buf;
       ecp = buf + len;
       a = (const uint16_t *)ia6;
       for (i = 0; i < 8; i++) {
               if (dcolon == 1) {
                       if (*a == 0) {
                               if (i == 7)
                                       ADDC(':');
                               a++;
                               continue;
                       } else
                               dcolon = 2;
               }
               if (*a == 0) {
                       if (dcolon == 0 && *(a + 1) == 0) {
                               if (i == 0)
                                       ADDC(':');
                               ADDC(':');
                               dcolon = 1;
                       } else {
                               ADDC('0');
                               ADDC(':');
                       }
                       a++;
                       continue;
               }
               d = (const u_char *)a;
               bp = cp + 1;

               ADDX((u_int)*d >> 4);
               ADDX(*d & 0xf);
               d++;
               ADDX((u_int)*d >> 4);
               ADDX(*d & 0xf);
               ADDC(':');
               a++;
       }
       if (cp > buf)
               --cp;
       if (ecp > buf) {
               if (cp < ecp)
                       *cp = '\0';
               else
                       *--ecp = '\0';
       }
       return (int)(cp - buf);
}

int
sin6_print(char *buf, size_t len, const void *v)
{
       const struct sockaddr_in6 *sin6 = v;
       const struct in6_addr *ia6 = &sin6->sin6_addr;
       char abuf[INET6_ADDRSTRLEN];

       if (!sin6->sin6_port)
               return in6_print(buf, len, ia6);
       in6_print(abuf, sizeof(abuf), ia6);
       return snprintf(buf, len, "[%s]:%hu", abuf, ntohs(sin6->sin6_port));
}