Initial Contribution
diff --git a/libc/netbsd/net/getnameinfo.c b/libc/netbsd/net/getnameinfo.c
new file mode 100644
index 0000000..5effa63
--- /dev/null
+++ b/libc/netbsd/net/getnameinfo.c
@@ -0,0 +1,519 @@
+/*	$NetBSD: getnameinfo.c,v 1.43 2006/02/17 15:58:26 ginsbach Exp $	*/
+/*	$KAME: getnameinfo.c,v 1.45 2000/09/25 22:43:56 itojun Exp $	*/
+
+/*
+ * Copyright (c) 2000 Ben Harris.
+ * Copyright (C) 1995, 1996, 1997, and 1998 WIDE Project.
+ * 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.
+ * 3. Neither the name of the project nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE PROJECT 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 PROJECT 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.
+ */
+
+/*
+ * Issues to be discussed:
+ * - Thread safe-ness must be checked
+ * - RFC2553 says that we should raise error on short buffer.  X/Open says
+ *   we need to truncate the result.  We obey RFC2553 (and X/Open should be
+ *   modified).  ipngwg rough consensus seems to follow RFC2553.
+ * - What is "local" in NI_FQDN?
+ * - NI_NAMEREQD and NI_NUMERICHOST conflict with each other.
+ * - (KAME extension) always attach textual scopeid (fe80::1%lo0), if
+ *   sin6_scope_id is filled - standardization status?
+ *   XXX breaks backward compat for code that expects no scopeid.
+ *   beware on merge.
+ */
+
+#include <sys/cdefs.h>
+#if defined(LIBC_SCCS) && !defined(lint)
+__RCSID("$NetBSD: getnameinfo.c,v 1.43 2006/02/17 15:58:26 ginsbach Exp $");
+#endif /* LIBC_SCCS and not lint */
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <net/if.h>
+#include <net/if_dl.h>
+#include <net/if_ieee1394.h>
+#include <net/if_types.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include "arpa_nameser.h"
+#include <assert.h>
+#include <limits.h>
+#include <netdb.h>
+#ifdef ANDROID_CHANGES
+#include "resolv_private.h"
+#else
+#include <resolv.h>
+#endif
+#include <stddef.h>
+#include <string.h>
+
+static const struct afd {
+	int		a_af;
+	socklen_t	a_addrlen;
+	socklen_t	a_socklen;
+	int		a_off;
+} afdl [] = {
+#ifdef INET6
+	{PF_INET6, sizeof(struct in6_addr), sizeof(struct sockaddr_in6),
+		offsetof(struct sockaddr_in6, sin6_addr)},
+#endif
+	{PF_INET, sizeof(struct in_addr), sizeof(struct sockaddr_in),
+		offsetof(struct sockaddr_in, sin_addr)},
+	{0, 0, 0, 0},
+};
+
+struct sockinet {
+	u_char	si_len;
+	u_char	si_family;
+	u_short	si_port;
+};
+
+static int getnameinfo_inet __P((const struct sockaddr *, socklen_t, char *,
+    socklen_t, char *, socklen_t, int));
+#ifdef INET6
+static int ip6_parsenumeric __P((const struct sockaddr *, const char *, char *,
+				 socklen_t, int));
+static int ip6_sa2str __P((const struct sockaddr_in6 *, char *, size_t,
+				 int));
+#endif
+static int getnameinfo_link __P((const struct sockaddr *, socklen_t, char *,
+    socklen_t, char *, socklen_t, int));
+static int hexname __P((const u_int8_t *, size_t, char *, socklen_t));
+
+/*
+ * Top-level getnameinfo() code.  Look at the address family, and pick an
+ * appropriate function to call.
+ */
+int getnameinfo(const struct sockaddr* sa, socklen_t salen, char* host, size_t hostlen, char* serv, size_t servlen, int flags)
+{
+	switch (sa->sa_family) {
+	case AF_INET:
+	case AF_INET6:
+		return getnameinfo_inet(sa, salen, host, hostlen,
+		    serv, servlen, flags);
+#if 0
+	case AF_LINK:
+		return getnameinfo_link(sa, salen, host, hostlen,
+		    serv, servlen, flags);
+#endif
+	default:
+		return EAI_FAMILY;
+	}
+}
+
+
+/*
+ * getnameinfo_inet():
+ * Format an IPv4 or IPv6 sockaddr into a printable string.
+ */
+static int
+getnameinfo_inet(sa, salen, host, hostlen, serv, servlen, flags)
+	const struct sockaddr *sa;
+	socklen_t salen;
+	char *host;
+	socklen_t hostlen;
+	char *serv;
+	socklen_t servlen;
+	int flags;
+{
+	const struct afd *afd;
+	struct servent *sp;
+	struct hostent *hp;
+	u_short port;
+	int family, i;
+	const char *addr;
+	u_int32_t v4a;
+	char numserv[512];
+	char numaddr[512];
+
+	/* sa is checked below */
+	/* host may be NULL */
+	/* serv may be NULL */
+
+	if (sa == NULL)
+		return EAI_FAIL;
+
+#ifdef BSD4_4
+	if (sa->sa_len != salen)
+		return EAI_FAIL;
+#endif
+
+	family = sa->sa_family;
+	for (i = 0; afdl[i].a_af; i++)
+		if (afdl[i].a_af == family) {
+			afd = &afdl[i];
+			goto found;
+		}
+	return EAI_FAMILY;
+
+ found:
+	if (salen != afd->a_socklen)
+		return EAI_FAIL;
+
+	/* network byte order */
+	port = ((const struct sockinet *)(const void *)sa)->si_port;
+	addr = (const char *)(const void *)sa + afd->a_off;
+
+	if (serv == NULL || servlen == 0) {
+		/*
+		 * do nothing in this case.
+		 * in case you are wondering if "&&" is more correct than
+		 * "||" here: rfc2553bis-03 says that serv == NULL OR
+		 * servlen == 0 means that the caller does not want the result.
+		 */
+	} else {
+		if (flags & NI_NUMERICSERV)
+			sp = NULL;
+		else {
+			sp = getservbyport(port,
+				(flags & NI_DGRAM) ? "udp" : "tcp");
+		}
+		if (sp) {
+			if (strlen(sp->s_name) + 1 > (size_t)servlen)
+				return EAI_MEMORY;
+			strlcpy(serv, sp->s_name, servlen);
+		} else {
+			snprintf(numserv, sizeof(numserv), "%u", ntohs(port));
+			if (strlen(numserv) + 1 > (size_t)servlen)
+				return EAI_MEMORY;
+			strlcpy(serv, numserv, servlen);
+		}
+	}
+
+	switch (sa->sa_family) {
+	case AF_INET:
+		v4a = (u_int32_t)
+		    ntohl(((const struct sockaddr_in *)
+		    (const void *)sa)->sin_addr.s_addr);
+		if (IN_MULTICAST(v4a) || IN_EXPERIMENTAL(v4a))
+			flags |= NI_NUMERICHOST;
+		v4a >>= IN_CLASSA_NSHIFT;
+		if (v4a == 0)
+			flags |= NI_NUMERICHOST;
+		break;
+#ifdef INET6
+	case AF_INET6:
+	    {
+		const struct sockaddr_in6 *sin6;
+		sin6 = (const struct sockaddr_in6 *)(const void *)sa;
+		switch (sin6->sin6_addr.s6_addr[0]) {
+		case 0x00:
+			if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr))
+				;
+			else if (IN6_IS_ADDR_LOOPBACK(&sin6->sin6_addr))
+				;
+			else
+				flags |= NI_NUMERICHOST;
+			break;
+		default:
+			if (IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr)) {
+				flags |= NI_NUMERICHOST;
+			}
+			else if (IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))
+				flags |= NI_NUMERICHOST;
+			break;
+		}
+	    }
+		break;
+#endif
+	}
+	if (host == NULL || hostlen == 0) {
+		/*
+		 * do nothing in this case.
+		 * in case you are wondering if "&&" is more correct than
+		 * "||" here: rfc2553bis-03 says that host == NULL or
+		 * hostlen == 0 means that the caller does not want the result.
+		 */
+	} else if (flags & NI_NUMERICHOST) {
+		size_t numaddrlen;
+
+		/* NUMERICHOST and NAMEREQD conflicts with each other */
+		if (flags & NI_NAMEREQD)
+			return EAI_NONAME;
+
+		switch(afd->a_af) {
+#ifdef INET6
+		case AF_INET6:
+		{
+			int error;
+
+			if ((error = ip6_parsenumeric(sa, addr, host,
+						      hostlen, flags)) != 0)
+				return(error);
+			break;
+		}
+#endif
+		default:
+			if (inet_ntop(afd->a_af, addr, numaddr, sizeof(numaddr))
+			    == NULL)
+				return EAI_SYSTEM;
+			numaddrlen = strlen(numaddr);
+			if (numaddrlen + 1 > (size_t)hostlen) /* don't forget terminator */
+				return EAI_MEMORY;
+			strlcpy(host, numaddr, hostlen);
+			break;
+		}
+	} else {
+		hp = gethostbyaddr(addr, afd->a_addrlen, afd->a_af);
+
+		if (hp) {
+#if 0
+			/*
+			 * commented out, since "for local host" is not
+			 * implemented here - see RFC2553 p30
+			 */
+			if (flags & NI_NOFQDN) {
+				char *p;
+				p = strchr(hp->h_name, '.');
+				if (p)
+					*p = '\0';
+			}
+#endif
+			if (strlen(hp->h_name) + 1 > (size_t)hostlen) {
+				return EAI_MEMORY;
+			}
+			strlcpy(host, hp->h_name, hostlen);
+		} else {
+			if (flags & NI_NAMEREQD)
+				return EAI_NONAME;
+			switch(afd->a_af) {
+#ifdef INET6
+			case AF_INET6:
+			{
+				int error;
+
+				if ((error = ip6_parsenumeric(sa, addr, host,
+							      hostlen,
+							      flags)) != 0)
+					return(error);
+				break;
+			}
+#endif
+			default:
+				if (inet_ntop(afd->a_af, addr, host,
+				    hostlen) == NULL)
+					return EAI_SYSTEM;
+				break;
+			}
+		}
+	}
+	return(0);
+}
+
+#ifdef INET6
+static int
+ip6_parsenumeric(sa, addr, host, hostlen, flags)
+	const struct sockaddr *sa;
+	const char *addr;
+	char *host;
+	socklen_t hostlen;
+	int flags;
+{
+	size_t numaddrlen;
+	char numaddr[512];
+
+	_DIAGASSERT(sa != NULL);
+	_DIAGASSERT(addr != NULL);
+	_DIAGASSERT(host != NULL);
+
+	if (inet_ntop(AF_INET6, addr, numaddr, sizeof(numaddr)) == NULL)
+		return EAI_SYSTEM;
+
+	numaddrlen = strlen(numaddr);
+	if (numaddrlen + 1 > hostlen) /* don't forget terminator */
+		return EAI_OVERFLOW;
+	strlcpy(host, numaddr, hostlen);
+
+	if (((const struct sockaddr_in6 *)(const void *)sa)->sin6_scope_id) {
+		char zonebuf[MAXHOSTNAMELEN];
+		int zonelen;
+
+		zonelen = ip6_sa2str(
+		    (const struct sockaddr_in6 *)(const void *)sa,
+		    zonebuf, sizeof(zonebuf), flags);
+		if (zonelen < 0)
+			return EAI_OVERFLOW;
+		if ((size_t) zonelen + 1 + numaddrlen + 1 > hostlen)
+			return EAI_OVERFLOW;
+		/* construct <numeric-addr><delim><zoneid> */
+		memcpy(host + numaddrlen + 1, zonebuf,
+		    (size_t)zonelen);
+		host[numaddrlen] = SCOPE_DELIMITER;
+		host[numaddrlen + 1 + zonelen] = '\0';
+	}
+
+	return 0;
+}
+
+/* ARGSUSED */
+static int
+ip6_sa2str(sa6, buf, bufsiz, flags)
+	const struct sockaddr_in6 *sa6;
+	char *buf;
+	size_t bufsiz;
+	int flags;
+{
+	unsigned int ifindex;
+	const struct in6_addr *a6;
+	int n;
+
+	_DIAGASSERT(sa6 != NULL);
+	_DIAGASSERT(buf != NULL);
+
+	ifindex = (unsigned int)sa6->sin6_scope_id;
+	a6 = &sa6->sin6_addr;
+
+#ifdef NI_NUMERICSCOPE
+	if ((flags & NI_NUMERICSCOPE) != 0) {
+		n = snprintf(buf, bufsiz, "%u", sa6->sin6_scope_id);
+		if (n < 0 || n >= bufsiz)
+			return -1;
+		else
+			return n;
+	}
+#endif
+
+	/* if_indextoname() does not take buffer size.  not a good api... */
+	if ((IN6_IS_ADDR_LINKLOCAL(a6) || IN6_IS_ADDR_MC_LINKLOCAL(a6)) &&
+	    bufsiz >= IF_NAMESIZE) {
+		char *p = if_indextoname(ifindex, buf);
+		if (p) {
+			return(strlen(p));
+		}
+	}
+
+	/* last resort */
+	n = snprintf(buf, bufsiz, "%u", sa6->sin6_scope_id);
+	if (n < 0 || (size_t) n >= bufsiz)
+		return -1;
+	else
+		return n;
+}
+#endif /* INET6 */
+
+
+/*
+ * getnameinfo_link():
+ * Format a link-layer address into a printable format, paying attention to
+ * the interface type.
+ */
+/* ARGSUSED */
+static int
+getnameinfo_link(const struct sockaddr *sa, socklen_t salen,
+    char *host, socklen_t hostlen, char *serv, socklen_t servlen,
+    int flags)
+{
+	const struct sockaddr_dl *sdl =
+	    (const struct sockaddr_dl *)(const void *)sa;
+	const struct ieee1394_hwaddr *iha;
+	int n;
+
+	if (serv != NULL && servlen > 0)
+		*serv = '\0';
+
+	if (sdl->sdl_nlen == 0 && sdl->sdl_alen == 0 && sdl->sdl_slen == 0) {
+		n = snprintf(host, hostlen, "link#%u", sdl->sdl_index);
+		if (n < 0 || (socklen_t) n > hostlen) {
+			*host = '\0';
+			return EAI_MEMORY;
+		}
+		return 0;
+	}
+
+	switch (sdl->sdl_type) {
+#ifdef IFT_ECONET
+	case IFT_ECONET:
+		if (sdl->sdl_alen < 2)
+			return EAI_FAMILY;
+		if (CLLADDR(sdl)[1] == 0)
+			n = snprintf(host, hostlen, "%u", CLLADDR(sdl)[0]);
+		else
+			n = snprintf(host, hostlen, "%u.%u",
+			    CLLADDR(sdl)[1], CLLADDR(sdl)[0]);
+		if (n < 0 || (socklen_t) n >= hostlen) {
+			*host = '\0';
+			return EAI_MEMORY;
+		} else
+			return 0;
+#endif
+	case IFT_IEEE1394:
+		if (sdl->sdl_alen < sizeof(iha->iha_uid))
+			return EAI_FAMILY;
+		iha =
+		    (const struct ieee1394_hwaddr *)(const void *)CLLADDR(sdl);
+		return hexname(iha->iha_uid, sizeof(iha->iha_uid),
+		    host, hostlen);
+	/*
+	 * The following have zero-length addresses.
+	 * IFT_ATM	(net/if_atmsubr.c)
+	 * IFT_FAITH	(net/if_faith.c)
+	 * IFT_GIF	(net/if_gif.c)
+	 * IFT_LOOP	(net/if_loop.c)
+	 * IFT_PPP	(net/if_ppp.c, net/if_spppsubr.c)
+	 * IFT_SLIP	(net/if_sl.c, net/if_strip.c)
+	 * IFT_STF	(net/if_stf.c)
+	 * IFT_L2VLAN	(net/if_vlan.c)
+	 * IFT_PROPVIRTUAL (net/if_bridge.h>
+	 */
+	/*
+	 * The following use IPv4 addresses as link-layer addresses:
+	 * IFT_OTHER	(net/if_gre.c)
+	 */
+	case IFT_ARCNET: /* default below is believed correct for all these. */
+	case IFT_ETHER:
+	case IFT_FDDI:
+	case IFT_HIPPI:
+	case IFT_ISO88025:
+	default:
+		return hexname((const u_int8_t *)CLLADDR(sdl),
+		    (size_t)sdl->sdl_alen, host, hostlen);
+	}
+}
+
+static int
+hexname(cp, len, host, hostlen)
+	const u_int8_t *cp;
+	char *host;
+	size_t len;
+	socklen_t hostlen;
+{
+	int n;
+	size_t i;
+	char *outp = host;
+
+	*outp = '\0';
+	for (i = 0; i < len; i++) {
+		n = snprintf(outp, hostlen, "%s%02x",
+		    i ? ":" : "", cp[i]);
+		if (n < 0 || (socklen_t) n >= hostlen) {
+			*host = '\0';
+			return EAI_MEMORY;
+		}
+		outp += n;
+		hostlen -= n;
+	}
+	return 0;
+}