xref: /freebsd/lib/libnetbsd/sockaddr_snprintf.c (revision a2f733abcff64628b7771a47089628b7327a88bd)
1*f5b9907cSEric van Gyzen /*	$NetBSD: sockaddr_snprintf.c,v 1.14 2016/12/29 18:30:55 christos Exp $	*/
2*f5b9907cSEric van Gyzen 
3*f5b9907cSEric van Gyzen /*-
4*f5b9907cSEric van Gyzen  * Copyright (c) 2004, 2016 The NetBSD Foundation, Inc.
5*f5b9907cSEric van Gyzen  * All rights reserved.
6*f5b9907cSEric van Gyzen  *
7*f5b9907cSEric van Gyzen  * This code is derived from software contributed to The NetBSD Foundation
8*f5b9907cSEric van Gyzen  * by Christos Zoulas.
9*f5b9907cSEric van Gyzen  *
10*f5b9907cSEric van Gyzen  * Redistribution and use in source and binary forms, with or without
11*f5b9907cSEric van Gyzen  * modification, are permitted provided that the following conditions
12*f5b9907cSEric van Gyzen  * are met:
13*f5b9907cSEric van Gyzen  * 1. Redistributions of source code must retain the above copyright
14*f5b9907cSEric van Gyzen  *    notice, this list of conditions and the following disclaimer.
15*f5b9907cSEric van Gyzen  * 2. Redistributions in binary form must reproduce the above copyright
16*f5b9907cSEric van Gyzen  *    notice, this list of conditions and the following disclaimer in the
17*f5b9907cSEric van Gyzen  *    documentation and/or other materials provided with the distribution.
18*f5b9907cSEric van Gyzen  *
19*f5b9907cSEric van Gyzen  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20*f5b9907cSEric van Gyzen  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21*f5b9907cSEric van Gyzen  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22*f5b9907cSEric van Gyzen  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23*f5b9907cSEric van Gyzen  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24*f5b9907cSEric van Gyzen  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25*f5b9907cSEric van Gyzen  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26*f5b9907cSEric van Gyzen  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27*f5b9907cSEric van Gyzen  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28*f5b9907cSEric van Gyzen  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29*f5b9907cSEric van Gyzen  * POSSIBILITY OF SUCH DAMAGE.
30*f5b9907cSEric van Gyzen  */
31*f5b9907cSEric van Gyzen #ifdef HAVE_CONFIG_H
32*f5b9907cSEric van Gyzen #include "config.h"
33*f5b9907cSEric van Gyzen #endif
34*f5b9907cSEric van Gyzen 
35*f5b9907cSEric van Gyzen #include <sys/param.h>
36*f5b9907cSEric van Gyzen #include <sys/types.h>
37*f5b9907cSEric van Gyzen #include <sys/socket.h>
38*f5b9907cSEric van Gyzen #include <sys/un.h>
39*f5b9907cSEric van Gyzen 
40*f5b9907cSEric van Gyzen #include <netinet/in.h>
41*f5b9907cSEric van Gyzen #ifdef HAVE_NET_IF_DL_H
42*f5b9907cSEric van Gyzen #include <net/if_dl.h>
43*f5b9907cSEric van Gyzen #endif
44*f5b9907cSEric van Gyzen 
45*f5b9907cSEric van Gyzen #include <stdio.h>
46*f5b9907cSEric van Gyzen #include <string.h>
47*f5b9907cSEric van Gyzen #include <errno.h>
48*f5b9907cSEric van Gyzen #include <stdlib.h>
49*f5b9907cSEric van Gyzen #include <util.h>
50*f5b9907cSEric van Gyzen #include <libutil.h>
51*f5b9907cSEric van Gyzen #include <netdb.h>
52*f5b9907cSEric van Gyzen 
53*f5b9907cSEric van Gyzen #ifdef BSD4_4
54*f5b9907cSEric van Gyzen # define SALEN(sa)	((sa)->sa ## _len)
55*f5b9907cSEric van Gyzen #else
56*f5b9907cSEric van Gyzen # define SALEN(sa)	((unsigned)sizeof(*sa))
57*f5b9907cSEric van Gyzen #endif
58*f5b9907cSEric van Gyzen 
59*f5b9907cSEric van Gyzen static int
debug_in(char * str,size_t len,const struct sockaddr_in * sin)60*f5b9907cSEric van Gyzen debug_in(char *str, size_t len, const struct sockaddr_in *sin)
61*f5b9907cSEric van Gyzen {
62*f5b9907cSEric van Gyzen 	return snprintf(str, len, "sin_len=%u, sin_family=%u, sin_port=%u, "
63*f5b9907cSEric van Gyzen 	    "sin_addr.s_addr=%08x",
64*f5b9907cSEric van Gyzen 	    SALEN(sin), sin->sin_family, sin->sin_port,
65*f5b9907cSEric van Gyzen 	    sin->sin_addr.s_addr);
66*f5b9907cSEric van Gyzen }
67*f5b9907cSEric van Gyzen 
68*f5b9907cSEric van Gyzen static int
debug_in6(char * str,size_t len,const struct sockaddr_in6 * sin6)69*f5b9907cSEric van Gyzen debug_in6(char *str, size_t len, const struct sockaddr_in6 *sin6)
70*f5b9907cSEric van Gyzen {
71*f5b9907cSEric van Gyzen 	const uint8_t *s = sin6->sin6_addr.s6_addr;
72*f5b9907cSEric van Gyzen 
73*f5b9907cSEric van Gyzen 	return snprintf(str, len, "sin6_len=%u, sin6_family=%u, sin6_port=%u, "
74*f5b9907cSEric van Gyzen 	    "sin6_flowinfo=%u, "
75*f5b9907cSEric van Gyzen 	    "sin6_addr=%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:"
76*f5b9907cSEric van Gyzen 	    "%02x:%02x:%02x:%02x:%02x:%02x, sin6_scope_id=%u",
77*f5b9907cSEric van Gyzen 	    SALEN(sin6), sin6->sin6_family, sin6->sin6_port,
78*f5b9907cSEric van Gyzen 	    sin6->sin6_flowinfo, s[0x0], s[0x1], s[0x2], s[0x3], s[0x4], s[0x5],
79*f5b9907cSEric van Gyzen 	    s[0x6], s[0x7], s[0x8], s[0x9], s[0xa], s[0xb], s[0xc], s[0xd],
80*f5b9907cSEric van Gyzen 	    s[0xe], s[0xf], sin6->sin6_scope_id);
81*f5b9907cSEric van Gyzen }
82*f5b9907cSEric van Gyzen 
83*f5b9907cSEric van Gyzen static int
debug_un(char * str,size_t len,const struct sockaddr_un * sun)84*f5b9907cSEric van Gyzen debug_un(char *str, size_t len, const struct sockaddr_un *sun)
85*f5b9907cSEric van Gyzen {
86*f5b9907cSEric van Gyzen 	return snprintf(str, len, "sun_len=%u, sun_family=%u, sun_path=%*s",
87*f5b9907cSEric van Gyzen 	    SALEN(sun), sun->sun_family, (int)sizeof(sun->sun_path),
88*f5b9907cSEric van Gyzen 	    sun->sun_path);
89*f5b9907cSEric van Gyzen }
90*f5b9907cSEric van Gyzen 
91*f5b9907cSEric van Gyzen #ifdef HAVE_NET_IF_DL_H
92*f5b9907cSEric van Gyzen static int
debug_dl(char * str,size_t len,const struct sockaddr_dl * sdl)93*f5b9907cSEric van Gyzen debug_dl(char *str, size_t len, const struct sockaddr_dl *sdl)
94*f5b9907cSEric van Gyzen {
95*f5b9907cSEric van Gyzen 	const uint8_t *s = (const void *)sdl->sdl_data;
96*f5b9907cSEric van Gyzen 
97*f5b9907cSEric van Gyzen 	return snprintf(str, len, "sdl_len=%u, sdl_family=%u, sdl_index=%u, "
98*f5b9907cSEric van Gyzen 	    "sdl_type=%u, sdl_nlen=%u, sdl_alen=%u, sdl_slen=%u, sdl_data="
99*f5b9907cSEric van Gyzen 	    "%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x:%02x",
100*f5b9907cSEric van Gyzen 	    SALEN(sdl), sdl->sdl_family, sdl->sdl_index,
101*f5b9907cSEric van Gyzen 	    sdl->sdl_type, sdl->sdl_nlen, sdl->sdl_alen, sdl->sdl_slen,
102*f5b9907cSEric van Gyzen 	    s[0x0], s[0x1], s[0x2], s[0x3], s[0x4], s[0x5],
103*f5b9907cSEric van Gyzen 	    s[0x6], s[0x7], s[0x8], s[0x9], s[0xa], s[0xb]);
104*f5b9907cSEric van Gyzen }
105*f5b9907cSEric van Gyzen #endif
106*f5b9907cSEric van Gyzen 
107*f5b9907cSEric van Gyzen int
sockaddr_snprintf(char * const sbuf,const size_t len,const char * const fmt,const struct sockaddr * const sa)108*f5b9907cSEric van Gyzen sockaddr_snprintf(char * const sbuf, const size_t len, const char * const fmt,
109*f5b9907cSEric van Gyzen     const struct sockaddr * const sa)
110*f5b9907cSEric van Gyzen {
111*f5b9907cSEric van Gyzen 	const void *a = NULL;
112*f5b9907cSEric van Gyzen 	char abuf[1024], nbuf[1024], *addr = NULL;
113*f5b9907cSEric van Gyzen 	char Abuf[1024], pbuf[32], *name = NULL, *port = NULL;
114*f5b9907cSEric van Gyzen 	char *ebuf = &sbuf[len - 1], *buf = sbuf;
115*f5b9907cSEric van Gyzen 	const char *ptr, *s;
116*f5b9907cSEric van Gyzen 	size_t salen;
117*f5b9907cSEric van Gyzen 	int p = -1;
118*f5b9907cSEric van Gyzen 	const struct sockaddr_in *sin4 = NULL;
119*f5b9907cSEric van Gyzen 	const struct sockaddr_in6 *sin6 = NULL;
120*f5b9907cSEric van Gyzen 	const struct sockaddr_un *sun = NULL;
121*f5b9907cSEric van Gyzen #ifdef HAVE_NET_IF_DL_H
122*f5b9907cSEric van Gyzen 	const struct sockaddr_dl *sdl = NULL;
123*f5b9907cSEric van Gyzen 	char *w = NULL;
124*f5b9907cSEric van Gyzen #endif
125*f5b9907cSEric van Gyzen 	int na = 1;
126*f5b9907cSEric van Gyzen 
127*f5b9907cSEric van Gyzen #define ADDC(c) do { if (buf < ebuf) *buf++ = c; else buf++; } \
128*f5b9907cSEric van Gyzen 	while (/*CONSTCOND*/0)
129*f5b9907cSEric van Gyzen #define ADDS(p) do { for (s = p; *s; s++) ADDC(*s); } \
130*f5b9907cSEric van Gyzen 	while (/*CONSTCOND*/0)
131*f5b9907cSEric van Gyzen #define ADDNA() do { if (na) ADDS("N/A"); } \
132*f5b9907cSEric van Gyzen 	while (/*CONSTCOND*/0)
133*f5b9907cSEric van Gyzen 
134*f5b9907cSEric van Gyzen 	switch (sa->sa_family) {
135*f5b9907cSEric van Gyzen 	case AF_UNSPEC:
136*f5b9907cSEric van Gyzen 		goto done;
137*f5b9907cSEric van Gyzen 	case AF_LOCAL:
138*f5b9907cSEric van Gyzen 		salen = sizeof(*sun);
139*f5b9907cSEric van Gyzen 		sun = ((const struct sockaddr_un *)(const void *)sa);
140*f5b9907cSEric van Gyzen 		(void)strlcpy(addr = abuf, sun->sun_path, sizeof(abuf));
141*f5b9907cSEric van Gyzen 		break;
142*f5b9907cSEric van Gyzen 	case AF_INET:
143*f5b9907cSEric van Gyzen 		salen = sizeof(*sin4);
144*f5b9907cSEric van Gyzen 		sin4 = ((const struct sockaddr_in *)(const void *)sa);
145*f5b9907cSEric van Gyzen 		p = ntohs(sin4->sin_port);
146*f5b9907cSEric van Gyzen 		a = &sin4->sin_addr;
147*f5b9907cSEric van Gyzen 		break;
148*f5b9907cSEric van Gyzen 	case AF_INET6:
149*f5b9907cSEric van Gyzen 		salen = sizeof(*sin6);
150*f5b9907cSEric van Gyzen 		sin6 = ((const struct sockaddr_in6 *)(const void *)sa);
151*f5b9907cSEric van Gyzen 		p = ntohs(sin6->sin6_port);
152*f5b9907cSEric van Gyzen 		a = &sin6->sin6_addr;
153*f5b9907cSEric van Gyzen 		break;
154*f5b9907cSEric van Gyzen #ifdef HAVE_NET_IF_DL_H
155*f5b9907cSEric van Gyzen 	case AF_LINK:
156*f5b9907cSEric van Gyzen 		sdl = ((const struct sockaddr_dl *)(const void *)sa);
157*f5b9907cSEric van Gyzen 		addr = abuf;
158*f5b9907cSEric van Gyzen 		if (sdl->sdl_slen == 0 && sdl->sdl_nlen == 0
159*f5b9907cSEric van Gyzen 		    && sdl->sdl_alen == 0) {
160*f5b9907cSEric van Gyzen 			salen = sizeof(*sdl);
161*f5b9907cSEric van Gyzen 			(void)snprintf(abuf, sizeof(abuf), "link#%hu",
162*f5b9907cSEric van Gyzen 			    sdl->sdl_index);
163*f5b9907cSEric van Gyzen 		} else {
164*f5b9907cSEric van Gyzen 			salen = sdl->sdl_slen + sdl->sdl_nlen +  sdl->sdl_alen;
165*f5b9907cSEric van Gyzen 			if (salen < sizeof(*sdl))
166*f5b9907cSEric van Gyzen 				salen = sizeof(*sdl);
167*f5b9907cSEric van Gyzen 			(void)strlcpy(abuf, link_ntoa(sdl), sizeof(abuf));
168*f5b9907cSEric van Gyzen 			if ((w = strchr(addr, ':')) != NULL) {
169*f5b9907cSEric van Gyzen 			    *w++ = '\0';
170*f5b9907cSEric van Gyzen 			    addr = w;
171*f5b9907cSEric van Gyzen 			}
172*f5b9907cSEric van Gyzen 		}
173*f5b9907cSEric van Gyzen 		break;
174*f5b9907cSEric van Gyzen #endif
175*f5b9907cSEric van Gyzen 	default:
176*f5b9907cSEric van Gyzen 		errno = EAFNOSUPPORT;
177*f5b9907cSEric van Gyzen 		return -1;
178*f5b9907cSEric van Gyzen 	}
179*f5b9907cSEric van Gyzen 
180*f5b9907cSEric van Gyzen 	if (addr == abuf)
181*f5b9907cSEric van Gyzen 		name = addr;
182*f5b9907cSEric van Gyzen 
183*f5b9907cSEric van Gyzen 	if (a && getnameinfo(sa, (socklen_t)salen, addr = abuf,
184*f5b9907cSEric van Gyzen 	    (unsigned int)sizeof(abuf), NULL, 0,
185*f5b9907cSEric van Gyzen 	    NI_NUMERICHOST|NI_NUMERICSERV) != 0)
186*f5b9907cSEric van Gyzen 		return -1;
187*f5b9907cSEric van Gyzen 
188*f5b9907cSEric van Gyzen 	for (ptr = fmt; *ptr; ptr++) {
189*f5b9907cSEric van Gyzen 		if (*ptr != '%') {
190*f5b9907cSEric van Gyzen 			ADDC(*ptr);
191*f5b9907cSEric van Gyzen 			continue;
192*f5b9907cSEric van Gyzen 		}
193*f5b9907cSEric van Gyzen 	  next_char:
194*f5b9907cSEric van Gyzen 		switch (*++ptr) {
195*f5b9907cSEric van Gyzen 		case '?':
196*f5b9907cSEric van Gyzen 			na = 0;
197*f5b9907cSEric van Gyzen 			goto next_char;
198*f5b9907cSEric van Gyzen 		case 'a':
199*f5b9907cSEric van Gyzen 			ADDS(addr);
200*f5b9907cSEric van Gyzen 			break;
201*f5b9907cSEric van Gyzen 		case 'p':
202*f5b9907cSEric van Gyzen 			if (p != -1) {
203*f5b9907cSEric van Gyzen 				(void)snprintf(nbuf, sizeof(nbuf), "%d", p);
204*f5b9907cSEric van Gyzen 				ADDS(nbuf);
205*f5b9907cSEric van Gyzen 			} else
206*f5b9907cSEric van Gyzen 				ADDNA();
207*f5b9907cSEric van Gyzen 			break;
208*f5b9907cSEric van Gyzen 		case 'f':
209*f5b9907cSEric van Gyzen 			(void)snprintf(nbuf, sizeof(nbuf), "%d", sa->sa_family);
210*f5b9907cSEric van Gyzen 			ADDS(nbuf);
211*f5b9907cSEric van Gyzen 			break;
212*f5b9907cSEric van Gyzen 		case 'l':
213*f5b9907cSEric van Gyzen 			(void)snprintf(nbuf, sizeof(nbuf), "%zu", salen);
214*f5b9907cSEric van Gyzen 			ADDS(nbuf);
215*f5b9907cSEric van Gyzen 			break;
216*f5b9907cSEric van Gyzen 		case 'A':
217*f5b9907cSEric van Gyzen 			if (name)
218*f5b9907cSEric van Gyzen 				ADDS(name);
219*f5b9907cSEric van Gyzen 			else if (!a)
220*f5b9907cSEric van Gyzen 				ADDNA();
221*f5b9907cSEric van Gyzen 			else {
222*f5b9907cSEric van Gyzen 				getnameinfo(sa, (socklen_t)salen, name = Abuf,
223*f5b9907cSEric van Gyzen 					(unsigned int)sizeof(nbuf), NULL, 0, 0);
224*f5b9907cSEric van Gyzen 				ADDS(name);
225*f5b9907cSEric van Gyzen 			}
226*f5b9907cSEric van Gyzen 			break;
227*f5b9907cSEric van Gyzen 		case 'P':
228*f5b9907cSEric van Gyzen 			if (port)
229*f5b9907cSEric van Gyzen 				ADDS(port);
230*f5b9907cSEric van Gyzen 			else if (p == -1)
231*f5b9907cSEric van Gyzen 				ADDNA();
232*f5b9907cSEric van Gyzen 			else {
233*f5b9907cSEric van Gyzen 				getnameinfo(sa, (socklen_t)salen, NULL, 0,
234*f5b9907cSEric van Gyzen 					port = pbuf,
235*f5b9907cSEric van Gyzen 					(unsigned int)sizeof(pbuf), 0);
236*f5b9907cSEric van Gyzen 				ADDS(port);
237*f5b9907cSEric van Gyzen 			}
238*f5b9907cSEric van Gyzen 			break;
239*f5b9907cSEric van Gyzen 		case 'I':
240*f5b9907cSEric van Gyzen #ifdef HAVE_NET_IF_DL_H
241*f5b9907cSEric van Gyzen 			if (sdl && addr != abuf) {
242*f5b9907cSEric van Gyzen 				ADDS(abuf);
243*f5b9907cSEric van Gyzen 			} else
244*f5b9907cSEric van Gyzen #endif
245*f5b9907cSEric van Gyzen 			{
246*f5b9907cSEric van Gyzen 				ADDNA();
247*f5b9907cSEric van Gyzen 			}
248*f5b9907cSEric van Gyzen 			break;
249*f5b9907cSEric van Gyzen 		case 'F':
250*f5b9907cSEric van Gyzen 			if (sin6) {
251*f5b9907cSEric van Gyzen 				(void)snprintf(nbuf, sizeof(nbuf), "%d",
252*f5b9907cSEric van Gyzen 				    sin6->sin6_flowinfo);
253*f5b9907cSEric van Gyzen 				ADDS(nbuf);
254*f5b9907cSEric van Gyzen 				break;
255*f5b9907cSEric van Gyzen 			} else {
256*f5b9907cSEric van Gyzen 				ADDNA();
257*f5b9907cSEric van Gyzen 			}
258*f5b9907cSEric van Gyzen 			break;
259*f5b9907cSEric van Gyzen 		case 'S':
260*f5b9907cSEric van Gyzen 			if (sin6) {
261*f5b9907cSEric van Gyzen 				(void)snprintf(nbuf, sizeof(nbuf), "%d",
262*f5b9907cSEric van Gyzen 				    sin6->sin6_scope_id);
263*f5b9907cSEric van Gyzen 				ADDS(nbuf);
264*f5b9907cSEric van Gyzen 				break;
265*f5b9907cSEric van Gyzen 			} else {
266*f5b9907cSEric van Gyzen 				ADDNA();
267*f5b9907cSEric van Gyzen 			}
268*f5b9907cSEric van Gyzen 			break;
269*f5b9907cSEric van Gyzen 		case 'R':
270*f5b9907cSEric van Gyzen 			{
271*f5b9907cSEric van Gyzen 				ADDNA();
272*f5b9907cSEric van Gyzen 			}
273*f5b9907cSEric van Gyzen 			break;
274*f5b9907cSEric van Gyzen 		case 'D':
275*f5b9907cSEric van Gyzen 			switch (sa->sa_family) {
276*f5b9907cSEric van Gyzen 			case AF_LOCAL:
277*f5b9907cSEric van Gyzen 				debug_un(nbuf, sizeof(nbuf), sun);
278*f5b9907cSEric van Gyzen 				break;
279*f5b9907cSEric van Gyzen 			case AF_INET:
280*f5b9907cSEric van Gyzen 				debug_in(nbuf, sizeof(nbuf), sin4);
281*f5b9907cSEric van Gyzen 				break;
282*f5b9907cSEric van Gyzen 			case AF_INET6:
283*f5b9907cSEric van Gyzen 				debug_in6(nbuf, sizeof(nbuf), sin6);
284*f5b9907cSEric van Gyzen 				break;
285*f5b9907cSEric van Gyzen #ifdef HAVE_NET_IF_DL_H
286*f5b9907cSEric van Gyzen 			case AF_LINK:
287*f5b9907cSEric van Gyzen 				debug_dl(nbuf, sizeof(nbuf), sdl);
288*f5b9907cSEric van Gyzen 				break;
289*f5b9907cSEric van Gyzen #endif
290*f5b9907cSEric van Gyzen 			default:
291*f5b9907cSEric van Gyzen 				abort();
292*f5b9907cSEric van Gyzen 			}
293*f5b9907cSEric van Gyzen 			ADDS(nbuf);
294*f5b9907cSEric van Gyzen 			break;
295*f5b9907cSEric van Gyzen 		default:
296*f5b9907cSEric van Gyzen 			ADDC('%');
297*f5b9907cSEric van Gyzen 			if (na == 0)
298*f5b9907cSEric van Gyzen 				ADDC('?');
299*f5b9907cSEric van Gyzen 			if (*ptr == '\0')
300*f5b9907cSEric van Gyzen 				goto done;
301*f5b9907cSEric van Gyzen 			/*FALLTHROUGH*/
302*f5b9907cSEric van Gyzen 		case '%':
303*f5b9907cSEric van Gyzen 			ADDC(*ptr);
304*f5b9907cSEric van Gyzen 			break;
305*f5b9907cSEric van Gyzen 		}
306*f5b9907cSEric van Gyzen 		na = 1;
307*f5b9907cSEric van Gyzen 	}
308*f5b9907cSEric van Gyzen done:
309*f5b9907cSEric van Gyzen 	if (buf < ebuf)
310*f5b9907cSEric van Gyzen 		*buf = '\0';
311*f5b9907cSEric van Gyzen 	else if (len != 0)
312*f5b9907cSEric van Gyzen 		sbuf[len - 1] = '\0';
313*f5b9907cSEric van Gyzen 	return (int)(buf - sbuf);
314*f5b9907cSEric van Gyzen }
315