1 /*	gethostent.c	4.10	85/01/21	*/
2 
3 #include <stdio.h>
4 #include <sys/types.h>
5 #include <sys/socket.h>
6 #include <netdb.h>
7 #include <ctype.h>
8 #include <ndbm.h>
9 
10 /*
11  * Internet version.
12  */
13 #define	MAXALIASES	35
14 #define	MAXADDRSIZE	14
15 
16 static FILE *hostf = NULL;
17 static char line[BUFSIZ+1];
18 static char hostaddr[MAXADDRSIZE];
19 static struct hostent host;
20 static char *host_aliases[MAXALIASES];
21 
22 /*
23  * The following is shared with gethostnamadr.c
24  */
25 char	*_host_file = "/etc/hosts";
26 int	_host_stayopen;
27 DBM	*_host_db;	/* set by gethostbyname(), gethostbyaddr() */
28 
29 static char *any();
30 
31 sethostent(f)
32 	int f;
33 {
34 	if (hostf != NULL)
35 		rewind(hostf);
36 	_host_stayopen |= f;
37 }
38 
39 endhostent()
40 {
41 	if (hostf) {
42 		fclose(hostf);
43 		hostf = NULL;
44 	}
45 	if (_host_db) {
46 		dbm_close(_host_db);
47 		_host_db = (DBM *)NULL;
48 	}
49 	_host_stayopen = 0;
50 }
51 
52 struct hostent *
53 gethostent()
54 {
55 	char *p;
56 	register char *cp, **q;
57 
58 	if (hostf == NULL && (hostf = fopen(_host_file, "r" )) == NULL)
59 		return (NULL);
60 again:
61 	if ((p = fgets(line, BUFSIZ, hostf)) == NULL)
62 		return (NULL);
63 	if (*p == '#')
64 		goto again;
65 	cp = any(p, "#\n");
66 	if (cp == NULL)
67 		goto again;
68 	*cp = '\0';
69 	cp = any(p, " \t");
70 	if (cp == NULL)
71 		goto again;
72 	*cp++ = '\0';
73 	/* THIS STUFF IS INTERNET SPECIFIC */
74 	host.h_addr = hostaddr;
75 	*((u_long *)host.h_addr) = inet_addr(p);
76 	host.h_length = sizeof (u_long);
77 	host.h_addrtype = AF_INET;
78 	while (*cp == ' ' || *cp == '\t')
79 		cp++;
80 	host.h_name = cp;
81 	q = host.h_aliases = host_aliases;
82 	cp = any(cp, " \t");
83 	if (cp != NULL)
84 		*cp++ = '\0';
85 	while (cp && *cp) {
86 		if (*cp == ' ' || *cp == '\t') {
87 			cp++;
88 			continue;
89 		}
90 		if (q < &host_aliases[MAXALIASES - 1])
91 			*q++ = cp;
92 		cp = any(cp, " \t");
93 		if (cp != NULL)
94 			*cp++ = '\0';
95 	}
96 	*q = NULL;
97 	return (&host);
98 }
99 
100 sethostfile(file)
101 	char *file;
102 {
103 	_host_file = file;
104 }
105 
106 static char *
107 any(cp, match)
108 	register char *cp;
109 	char *match;
110 {
111 	register char *mp, c;
112 
113 	while (c = *cp) {
114 		for (mp = match; *mp; mp++)
115 			if (*mp == c)
116 				return (cp);
117 		cp++;
118 	}
119 	return ((char *)0);
120 }
121