[unix-history] / usr / src / lib / libc / net / gethostnamadr.c

/*
 * Copyright (c) 1985, 1988 Regents of the University of California.
 * All rights reserved.
 *
 * %sccs.include.redist.c%
 */

#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)gethostnamadr.c	6.42 (Berkeley) %G%";
#endif /* LIBC_SCCS and not lint */

#include <sys/param.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <ctype.h>
#include <netdb.h>
#include <stdio.h>
#include <errno.h>
#include <arpa/inet.h>
#include <arpa/nameser.h>
#include <resolv.h>

#define	MAXALIASES	35
#define	MAXADDRS	35

static char *h_addr_ptrs[MAXADDRS + 1];

static struct hostent host;
static char *host_aliases[MAXALIASES];
static char hostbuf[BUFSIZ+1];
static struct in_addr host_addr;
static FILE *hostf = NULL;
static char hostaddr[MAXADDRS];
static char *host_addrs[2];
static int stayopen = 0;
char *strpbrk();

#if PACKETSZ > 1024
#define	MAXPACKET	PACKETSZ
#else
#define	MAXPACKET	1024
#endif

typedef union {
    HEADER hdr;
    u_char buf[MAXPACKET];
} querybuf;

typedef union {
    long al;
    char ac;
} align;


int h_errno;
extern errno;

static struct hostent *
getanswer(answer, anslen, iquery)
	querybuf *answer;
	int anslen;
	int iquery;
{
	register HEADER *hp;
	register u_char *cp;
	register int n;
	u_char *eom;
	char *bp, **ap;
	int type, class, buflen, ancount, qdcount;
	int haveanswer, getclass = C_ANY;
	char **hap;

	eom = answer->buf + anslen;
	/*
	 * find first satisfactory answer
	 */
	hp = &answer->hdr;
	ancount = ntohs(hp->ancount);
	qdcount = ntohs(hp->qdcount);
	bp = hostbuf;
	buflen = sizeof(hostbuf);
	cp = answer->buf + sizeof(HEADER);
	if (qdcount) {
		if (iquery) {
			if ((n = dn_expand((char *)answer->buf, eom,
			     cp, bp, buflen)) < 0) {
				h_errno = NO_RECOVERY;
				return ((struct hostent *) NULL);
			}
			cp += n + QFIXEDSZ;
			host.h_name = bp;
			n = strlen(bp) + 1;
			bp += n;
			buflen -= n;
		} else
			cp += __dn_skipname(cp, eom) + QFIXEDSZ;
		while (--qdcount > 0)
			cp += __dn_skipname(cp, eom) + QFIXEDSZ;
	} else if (iquery) {
		if (hp->aa)
			h_errno = HOST_NOT_FOUND;
		else
			h_errno = TRY_AGAIN;
		return ((struct hostent *) NULL);
	}
	ap = host_aliases;
	*ap = NULL;
	host.h_aliases = host_aliases;
	hap = h_addr_ptrs;
	*hap = NULL;
#if BSD >= 43 || defined(h_addr)	/* new-style hostent structure */
	host.h_addr_list = h_addr_ptrs;
#endif
	haveanswer = 0;
	while (--ancount >= 0 && cp < eom) {
		if ((n = dn_expand((char *)answer->buf, eom, cp, bp, buflen)) < 0)
			break;
		cp += n;
		type = _getshort(cp);
 		cp += sizeof(u_short);
		class = _getshort(cp);
 		cp += sizeof(u_short) + sizeof(u_long);
		n = _getshort(cp);
		cp += sizeof(u_short);
		if (type == T_CNAME) {
			cp += n;
			if (ap >= &host_aliases[MAXALIASES-1])
				continue;
			*ap++ = bp;
			n = strlen(bp) + 1;
			bp += n;
			buflen -= n;
			continue;
		}
		if (iquery && type == T_PTR) {
			if ((n = dn_expand((char *)answer->buf, eom,
			    cp, bp, buflen)) < 0) {
				cp += n;
				continue;
			}
			cp += n;
			host.h_name = bp;
			return(&host);
		}
		if (iquery || type != T_A)  {
#ifdef DEBUG
			if (_res.options & RES_DEBUG)
				printf("unexpected answer type %d, size %d\n",
					type, n);
#endif
			cp += n;
			continue;
		}
		if (haveanswer) {
			if (n != host.h_length) {
				cp += n;
				continue;
			}
			if (class != getclass) {
				cp += n;
				continue;
			}
		} else {
			host.h_length = n;
			getclass = class;
			host.h_addrtype = (class == C_IN) ? AF_INET : AF_UNSPEC;
			if (!iquery) {
				host.h_name = bp;
				bp += strlen(bp) + 1;
			}
		}

		bp += sizeof(align) - ((u_long)bp % sizeof(align));

		if (bp + n >= &hostbuf[sizeof(hostbuf)]) {
#ifdef DEBUG
			if (_res.options & RES_DEBUG)
				printf("size (%d) too big\n", n);
#endif
			break;
		}
		bcopy(cp, *hap++ = bp, n);
		bp +=n;
		cp += n;
		haveanswer++;
	}
	if (haveanswer) {
		*ap = NULL;
#if BSD >= 43 || defined(h_addr)	/* new-style hostent structure */
		*hap = NULL;
#else
		host.h_addr = h_addr_ptrs[0];
#endif
		return (&host);
	} else {
		h_errno = TRY_AGAIN;
		return ((struct hostent *) NULL);
	}
}

struct hostent *
gethostbyname(name)
	char *name;
{
	querybuf buf;
	register char *cp;
	int n;
	extern struct hostent *_gethtbyname();

	/*
	 * disallow names consisting only of digits/dots, unless
	 * they end in a dot.
	 */
	if (isdigit(name[0]))
		for (cp = name;; ++cp) {
			if (!*cp) {
				if (*--cp == '.')
					break;
				/*
				 * All-numeric, no dot at the end.
				 * Fake up a hostent as if we'd actually
				 * done a lookup.  What if someone types
				 * 255.255.255.255?  The test below will
				 * succeed spuriously... ???
				 */
				if ((host_addr.s_addr = inet_addr(name)) == -1) {
					h_errno = HOST_NOT_FOUND;
					return((struct hostent *) NULL);
				}
				host.h_name = name;
				host.h_aliases = host_aliases;
				host_aliases[0] = NULL;
				host.h_addrtype = AF_INET;
				host.h_length = sizeof(u_long);
				h_addr_ptrs[0] = (char *)&host_addr;
				h_addr_ptrs[1] = (char *)0;
#if BSD >= 43 || defined(h_addr)	/* new-style hostent structure */
				host.h_addr_list = h_addr_ptrs;
#else
				host.h_addr = h_addr_ptrs[0];
#endif
				return (&host);
			}
			if (!isdigit(*cp) && *cp != '.') 
				break;
		}

	if ((n = res_search(name, C_IN, T_A, buf.buf, sizeof(buf))) < 0) {
#ifdef DEBUG
		if (_res.options & RES_DEBUG)
			printf("res_search failed\n");
#endif
		if (errno == ECONNREFUSED)
			return (_gethtbyname(name));
		else
			return ((struct hostent *) NULL);
	}
	return (getanswer(&buf, n, 0));
}

struct hostent *
gethostbyaddr(addr, len, type)
	char *addr;
	int len, type;
{
	int n;
	querybuf buf;
	register struct hostent *hp;
	char qbuf[MAXDNAME];
	extern struct hostent *_gethtbyaddr();
	
	if (type != AF_INET)
		return ((struct hostent *) NULL);
	(void)sprintf(qbuf, "%u.%u.%u.%u.in-addr.arpa",
		((unsigned)addr[3] & 0xff),
		((unsigned)addr[2] & 0xff),
		((unsigned)addr[1] & 0xff),
		((unsigned)addr[0] & 0xff));
	n = res_query(qbuf, C_IN, T_PTR, (char *)&buf, sizeof(buf));
	if (n < 0) {
#ifdef DEBUG
		if (_res.options & RES_DEBUG)
			printf("res_query failed\n");
#endif
		if (errno == ECONNREFUSED)
			return (_gethtbyaddr(addr, len, type));
		return ((struct hostent *) NULL);
	}
	hp = getanswer(&buf, n, 1);
	if (hp == NULL)
		return ((struct hostent *) NULL);
	hp->h_addrtype = type;
	hp->h_length = len;
	h_addr_ptrs[0] = (char *)&host_addr;
	h_addr_ptrs[1] = (char *)0;
	host_addr = *(struct in_addr *)addr;
#if BSD < 43 && !defined(h_addr)	/* new-style hostent structure */
	hp->h_addr = h_addr_ptrs[0];
#endif
	return(hp);
}

_sethtent(f)
	int f;
{
	if (hostf == NULL)
		hostf = fopen(_PATH_HOSTS, "r" );
	else
		rewind(hostf);
	stayopen |= f;
}

_endhtent()
{
	if (hostf && !stayopen) {
		(void) fclose(hostf);
		hostf = NULL;
	}
}

struct hostent *
_gethtent()
{
	char *p;
	register char *cp, **q;

	if (hostf == NULL && (hostf = fopen(_PATH_HOSTS, "r" )) == NULL)
		return (NULL);
again:
	if ((p = fgets(hostbuf, BUFSIZ, hostf)) == NULL)
		return (NULL);
	if (*p == '#')
		goto again;
	cp = strpbrk(p, "#\n");
	if (cp == NULL)
		goto again;
	*cp = '\0';
	cp = strpbrk(p, " \t");
	if (cp == NULL)
		goto again;
	*cp++ = '\0';
	/* THIS STUFF IS INTERNET SPECIFIC */
#if BSD >= 43 || defined(h_addr)	/* new-style hostent structure */
	host.h_addr_list = host_addrs;
#endif
	host.h_addr = hostaddr;
	*((u_long *)host.h_addr) = inet_addr(p);
	host.h_length = sizeof (u_long);
	host.h_addrtype = AF_INET;
	while (*cp == ' ' || *cp == '\t')
		cp++;
	host.h_name = cp;
	q = host.h_aliases = host_aliases;
	cp = strpbrk(cp, " \t");
	if (cp != NULL) 
		*cp++ = '\0';
	while (cp && *cp) {
		if (*cp == ' ' || *cp == '\t') {
			cp++;
			continue;
		}
		if (q < &host_aliases[MAXALIASES - 1])
			*q++ = cp;
		cp = strpbrk(cp, " \t");
		if (cp != NULL)
			*cp++ = '\0';
	}
	*q = NULL;
	return (&host);
}

struct hostent *
_gethtbyname(name)
	char *name;
{
	register struct hostent *p;
	register char **cp;
	
	_sethtent(0);
	while (p = _gethtent()) {
		if (strcasecmp(p->h_name, name) == 0)
			break;
		for (cp = p->h_aliases; *cp != 0; cp++)
			if (strcasecmp(*cp, name) == 0)
				goto found;
	}
found:
	_endhtent();
	return (p);
}

struct hostent *
_gethtbyaddr(addr, len, type)
	char *addr;
	int len, type;
{
	register struct hostent *p;

	_sethtent(0);
	while (p = _gethtent())
		if (p->h_addrtype == type && !bcmp(p->h_addr, addr, len))
			break;
	_endhtent();
	return (p);
}
Commit	Line	Data
8ea4199d	1	/*
5cfeec12 KB	2	* Copyright (c) 1985, 1988 Regents of the University of California.
	3	* All rights reserved.
	4	*
269a7923	5	* %sccs.include.redist.c%
8ea4199d DF	6	*/
8ea4199d DF	7
2ce81398	8	#if defined(LIBC_SCCS) && !defined(lint)
371d3c9b	9	static char sccsid[] = "@(#)gethostnamadr.c 6.42 (Berkeley) %G%";
5cfeec12	10	#endif /* LIBC_SCCS and not lint */
b423e985	11
7f2f8dda	12	#include <sys/param.h>
f784656b RC	13	#include <sys/socket.h>
f784656b RC	14	#include <netinet/in.h>
12379d92	15	#include <ctype.h>
337257b2	16	#include <netdb.h>
f784656b	17	#include <stdio.h>
12379d92	18	#include <errno.h>
2795c575	19	#include <arpa/inet.h>
aa678832	20	#include <arpa/nameser.h>
f94b2f50	21	#include <resolv.h>
337257b2 RC	22
337257b2 RC	23	#define MAXALIASES 35
0e9a6a67	24	#define MAXADDRS 35
337257b2	25
412fa3e3 JB	26	static char *h_addr_ptrs[MAXADDRS + 1];
	27
	28	static struct hostent host;
337257b2	29	static char *host_aliases[MAXALIASES];
291cd39e	30	static char hostbuf[BUFSIZ+1];
4682c40f	31	static struct in_addr host_addr;
12379d92	32	static FILE *hostf = NULL;
12379d92 KD	33	static char hostaddr[MAXADDRS];
	34	static char *host_addrs[2];
	35	static int stayopen = 0;
81f99a97	36	char *strpbrk();
3a87f357	37
b6a43c3e	38	#if PACKETSZ > 1024
0e9a6a67	39	#define MAXPACKET PACKETSZ
b6a43c3e	40	#else
0e9a6a67	41	#define MAXPACKET 1024
b6a43c3e MK	42	#endif
b6a43c3e MK	43
c675dcaa	44	typedef union {
0e9a6a67 KB	45	HEADER hdr;
0e9a6a67 KB	46	u_char buf[MAXPACKET];
c675dcaa KD	47	} querybuf;
c675dcaa KD	48
e714052f	49	typedef union {
c675dcaa KD	50	long al;
	51	char ac;
	52	} align;
	53
6f4c7128	54
fe8457be	55	int h_errno;
12379d92	56	extern errno;
fe8457be	57
337257b2	58	static struct hostent *
0e9a6a67 KB	59	getanswer(answer, anslen, iquery)
	60	querybuf *answer;
	61	int anslen;
	62	int iquery;
337257b2	63	{
f784656b	64	register HEADER *hp;
0e9a6a67	65	register u_char *cp;
f784656b	66	register int n;
0e9a6a67 KB	67	u_char *eom;
0e9a6a67 KB	68	char bp, *ap;
2795c575 KD	69	int type, class, buflen, ancount, qdcount;
2795c575 KD	70	int haveanswer, getclass = C_ANY;
412fa3e3	71	char **hap;
337257b2	72
0e9a6a67	73	eom = answer->buf + anslen;
f784656b RC	74	/*
	75	* find first satisfactory answer
	76	*/
0e9a6a67	77	hp = &answer->hdr;
f784656b	78	ancount = ntohs(hp->ancount);
4682c40f	79	qdcount = ntohs(hp->qdcount);
f784656b RC	80	bp = hostbuf;
f784656b RC	81	buflen = sizeof(hostbuf);
0e9a6a67	82	cp = answer->buf + sizeof(HEADER);
4682c40f	83	if (qdcount) {
f784656b	84	if (iquery) {
0e9a6a67	85	if ((n = dn_expand((char *)answer->buf, eom,
91c656a0	86	cp, bp, buflen)) < 0) {
fe8457be	87	h_errno = NO_RECOVERY;
e0313454	88	return ((struct hostent *) NULL);
fe8457be	89	}
f784656b RC	90	cp += n + QFIXEDSZ;
	91	host.h_name = bp;
	92	n = strlen(bp) + 1;
	93	bp += n;
	94	buflen -= n;
	95	} else
371d3c9b	96	cp += __dn_skipname(cp, eom) + QFIXEDSZ;
4682c40f	97	while (--qdcount > 0)
371d3c9b	98	cp += __dn_skipname(cp, eom) + QFIXEDSZ;
fe8457be KD	99	} else if (iquery) {
	100	if (hp->aa)
	101	h_errno = HOST_NOT_FOUND;
	102	else
	103	h_errno = TRY_AGAIN;
e0313454	104	return ((struct hostent *) NULL);
fe8457be	105	}
412fa3e3	106	ap = host_aliases;
ee21fae8	107	*ap = NULL;
412fa3e3 JB	108	host.h_aliases = host_aliases;
412fa3e3 JB	109	hap = h_addr_ptrs;
ee21fae8	110	*hap = NULL;
15eda464	111	#if BSD >= 43 \|\| defined(h_addr) /* new-style hostent structure */
412fa3e3	112	host.h_addr_list = h_addr_ptrs;
da75bcd9	113	#endif
412fa3e3	114	haveanswer = 0;
f784656b	115	while (--ancount >= 0 && cp < eom) {
0e9a6a67	116	if ((n = dn_expand((char *)answer->buf, eom, cp, bp, buflen)) < 0)
412fa3e3	117	break;
f784656b	118	cp += n;
b1772b2c	119	type = _getshort(cp);
f784656b	120	cp += sizeof(u_short);
b1772b2c	121	class = _getshort(cp);
f784656b	122	cp += sizeof(u_short) + sizeof(u_long);
b1772b2c	123	n = _getshort(cp);
f784656b RC	124	cp += sizeof(u_short);
	125	if (type == T_CNAME) {
	126	cp += n;
	127	if (ap >= &host_aliases[MAXALIASES-1])
	128	continue;
	129	*ap++ = bp;
	130	n = strlen(bp) + 1;
	131	bp += n;
	132	buflen -= n;
	133	continue;
	134	}
0e9a6a67 KB	135	if (iquery && type == T_PTR) {
0e9a6a67 KB	136	if ((n = dn_expand((char *)answer->buf, eom,
2795c575	137	cp, bp, buflen)) < 0) {
4682c40f JB	138	cp += n;
	139	continue;
	140	}
	141	cp += n;
	142	host.h_name = bp;
	143	return(&host);
	144	}
0e9a6a67	145	if (iquery \|\| type != T_A) {
d1c1ab68	146	#ifdef DEBUG
f784656b RC	147	if (_res.options & RES_DEBUG)
	148	printf("unexpected answer type %d, size %d\n",
	149	type, n);
d1c1ab68	150	#endif
412fa3e3	151	cp += n;
f784656b RC	152	continue;
f784656b RC	153	}
412fa3e3 JB	154	if (haveanswer) {
	155	if (n != host.h_length) {
	156	cp += n;
	157	continue;
	158	}
	159	if (class != getclass) {
	160	cp += n;
	161	continue;
	162	}
	163	} else {
	164	host.h_length = n;
	165	getclass = class;
82a65531	166	host.h_addrtype = (class == C_IN) ? AF_INET : AF_UNSPEC;
412fa3e3 JB	167	if (!iquery) {
	168	host.h_name = bp;
	169	bp += strlen(bp) + 1;
	170	}
f784656b	171	}
c675dcaa	172
8ad123ce	173	bp += sizeof(align) - ((u_long)bp % sizeof(align));
c675dcaa	174
f784656b	175	if (bp + n >= &hostbuf[sizeof(hostbuf)]) {
d1c1ab68	176	#ifdef DEBUG
f784656b RC	177	if (_res.options & RES_DEBUG)
f784656b RC	178	printf("size (%d) too big\n", n);
d1c1ab68	179	#endif
412fa3e3	180	break;
f784656b	181	}
412fa3e3 JB	182	bcopy(cp, *hap++ = bp, n);
	183	bp +=n;
	184	cp += n;
	185	haveanswer++;
f784656b	186	}
412fa3e3 JB	187	if (haveanswer) {
412fa3e3 JB	188	*ap = NULL;
15eda464	189	#if BSD >= 43 \|\| defined(h_addr) /* new-style hostent structure */
412fa3e3	190	*hap = NULL;
8ad123ce MK	191	#else
	192	host.h_addr = h_addr_ptrs[0];
	193	#endif
412fa3e3	194	return (&host);
fe8457be KD	195	} else {
fe8457be KD	196	h_errno = TRY_AGAIN;
e0313454	197	return ((struct hostent *) NULL);
fe8457be	198	}
337257b2 RC	199	}
	200
	201	struct hostent *
f784656b RC	202	gethostbyname(name)
f784656b RC	203	char *name;
337257b2	204	{
0e9a6a67 KB	205	querybuf buf;
0e9a6a67 KB	206	register char *cp;
f784656b	207	int n;
12379d92	208	extern struct hostent *_gethtbyname();
337257b2	209
693999f7 KB	210	/*
	211	* disallow names consisting only of digits/dots, unless
	212	* they end in a dot.
	213	*/
	214	if (isdigit(name[0]))
	215	for (cp = name;; ++cp) {
	216	if (!*cp) {
	217	if (*--cp == '.')
	218	break;
7468ba44 JB	219	/*
	220	* All-numeric, no dot at the end.
	221	* Fake up a hostent as if we'd actually
	222	* done a lookup. What if someone types
	223	* 255.255.255.255? The test below will
	224	* succeed spuriously... ???
	225	*/
	226	if ((host_addr.s_addr = inet_addr(name)) == -1) {
	227	h_errno = HOST_NOT_FOUND;
	228	return((struct hostent *) NULL);
	229	}
	230	host.h_name = name;
	231	host.h_aliases = host_aliases;
	232	host_aliases[0] = NULL;
	233	host.h_addrtype = AF_INET;
	234	host.h_length = sizeof(u_long);
	235	h_addr_ptrs[0] = (char *)&host_addr;
	236	h_addr_ptrs[1] = (char *)0;
	237	#if BSD >= 43 \|\| defined(h_addr) /* new-style hostent structure */
	238	host.h_addr_list = h_addr_ptrs;
	239	#else
	240	host.h_addr = h_addr_ptrs[0];
	241	#endif
	242	return (&host);
693999f7 KB	243	}
	244	if (!isdigit(cp) && cp != '.')
	245	break;
	246	}
216ea7e1	247
0e9a6a67	248	if ((n = res_search(name, C_IN, T_A, buf.buf, sizeof(buf))) < 0) {
d1c1ab68	249	#ifdef DEBUG
f784656b	250	if (_res.options & RES_DEBUG)
0e9a6a67	251	printf("res_search failed\n");
d1c1ab68	252	#endif
0e9a6a67 KB	253	if (errno == ECONNREFUSED)
	254	return (_gethtbyname(name));
	255	else
	256	return ((struct hostent *) NULL);
3a87f357	257	}
0e9a6a67	258	return (getanswer(&buf, n, 0));
337257b2 RC	259	}
	260
	261	struct hostent *
f784656b	262	gethostbyaddr(addr, len, type)
337257b2	263	char *addr;
f784656b	264	int len, type;
337257b2	265	{
f784656b	266	int n;
c675dcaa	267	querybuf buf;
4682c40f JB	268	register struct hostent *hp;
4682c40f JB	269	char qbuf[MAXDNAME];
12379d92 KD	270	extern struct hostent *_gethtbyaddr();
12379d92 KD	271
f784656b	272	if (type != AF_INET)
e0313454	273	return ((struct hostent *) NULL);
0d7830cc	274	(void)sprintf(qbuf, "%u.%u.%u.%u.in-addr.arpa",
fe8457be KD	275	((unsigned)addr[3] & 0xff),
	276	((unsigned)addr[2] & 0xff),
	277	((unsigned)addr[1] & 0xff),
	278	((unsigned)addr[0] & 0xff));
0e9a6a67	279	n = res_query(qbuf, C_IN, T_PTR, (char *)&buf, sizeof(buf));
f784656b	280	if (n < 0) {
d1c1ab68	281	#ifdef DEBUG
f784656b	282	if (_res.options & RES_DEBUG)
0e9a6a67	283	printf("res_query failed\n");
d1c1ab68	284	#endif
0e9a6a67	285	if (errno == ECONNREFUSED)
6d1927cd	286	return (_gethtbyaddr(addr, len, type));
e0313454	287	return ((struct hostent *) NULL);
f268b9fa	288	}
0e9a6a67	289	hp = getanswer(&buf, n, 1);
12379d92	290	if (hp == NULL)
e0313454	291	return ((struct hostent *) NULL);
4682c40f JB	292	hp->h_addrtype = type;
4682c40f JB	293	hp->h_length = len;
c7683dcd	294	h_addr_ptrs[0] = (char *)&host_addr;
4682c40f JB	295	h_addr_ptrs[1] = (char *)0;
4682c40f JB	296	host_addr = (struct in_addr )addr;
7468ba44 JB	297	#if BSD < 43 && !defined(h_addr) /* new-style hostent structure */
	298	hp->h_addr = h_addr_ptrs[0];
	299	#endif
4682c40f	300	return(hp);
337257b2	301	}
c675dcaa	302
12379d92 KD	303	_sethtent(f)
	304	int f;
	305	{
	306	if (hostf == NULL)
29eb0a7d	307	hostf = fopen(_PATH_HOSTS, "r" );
12379d92 KD	308	else
	309	rewind(hostf);
	310	stayopen \|= f;
	311	}
	312
	313	_endhtent()
	314	{
	315	if (hostf && !stayopen) {
2795c575	316	(void) fclose(hostf);
12379d92 KD	317	hostf = NULL;
	318	}
	319	}
	320
	321	struct hostent *
	322	_gethtent()
	323	{
	324	char *p;
	325	register char cp, *q;
	326
29eb0a7d	327	if (hostf == NULL && (hostf = fopen(_PATH_HOSTS, "r" )) == NULL)
12379d92 KD	328	return (NULL);
12379d92 KD	329	again:
0e9a6a67	330	if ((p = fgets(hostbuf, BUFSIZ, hostf)) == NULL)
12379d92 KD	331	return (NULL);
	332	if (*p == '#')
	333	goto again;
81f99a97	334	cp = strpbrk(p, "#\n");
12379d92 KD	335	if (cp == NULL)
	336	goto again;
	337	*cp = '\0';
81f99a97	338	cp = strpbrk(p, " \t");
12379d92 KD	339	if (cp == NULL)
	340	goto again;
	341	*cp++ = '\0';
	342	/* THIS STUFF IS INTERNET SPECIFIC */
15eda464	343	#if BSD >= 43 \|\| defined(h_addr) /* new-style hostent structure */
12379d92	344	host.h_addr_list = host_addrs;
da75bcd9	345	#endif
12379d92 KD	346	host.h_addr = hostaddr;
	347	((u_long )host.h_addr) = inet_addr(p);
	348	host.h_length = sizeof (u_long);
	349	host.h_addrtype = AF_INET;
	350	while (cp == ' ' \|\| cp == '\t')
	351	cp++;
	352	host.h_name = cp;
	353	q = host.h_aliases = host_aliases;
81f99a97	354	cp = strpbrk(cp, " \t");
12379d92 KD	355	if (cp != NULL)
	356	*cp++ = '\0';
	357	while (cp && *cp) {
	358	if (cp == ' ' \|\| cp == '\t') {
	359	cp++;
	360	continue;
	361	}
	362	if (q < &host_aliases[MAXALIASES - 1])
	363	*q++ = cp;
81f99a97	364	cp = strpbrk(cp, " \t");
12379d92 KD	365	if (cp != NULL)
	366	*cp++ = '\0';
	367	}
	368	*q = NULL;
	369	return (&host);
	370	}
	371
12379d92 KD	372	struct hostent *
	373	_gethtbyname(name)
	374	char *name;
	375	{
	376	register struct hostent *p;
	377	register char **cp;
1e26987f	378
12379d92 KD	379	_sethtent(0);
12379d92 KD	380	while (p = _gethtent()) {
46d92023	381	if (strcasecmp(p->h_name, name) == 0)
12379d92 KD	382	break;
12379d92 KD	383	for (cp = p->h_aliases; *cp != 0; cp++)
46d92023	384	if (strcasecmp(*cp, name) == 0)
12379d92 KD	385	goto found;
	386	}
	387	found:
	388	_endhtent();
	389	return (p);
	390	}
	391
	392	struct hostent *
	393	_gethtbyaddr(addr, len, type)
	394	char *addr;
	395	int len, type;
	396	{
	397	register struct hostent *p;
	398
	399	_sethtent(0);
	400	while (p = _gethtent())
3f2cac51	401	if (p->h_addrtype == type && !bcmp(p->h_addr, addr, len))
12379d92 KD	402	break;
	403	_endhtent();
	404	return (p);
	405	}