xref: /csrg-svn/old/gettable/gettable.c (revision 15167)
1 
2 #ifndef lint
3 static char sccsid[] = "@(#)gettable.c	4.3 (Berkeley) 10/05/83";
4 #endif
5 
6 #include <sys/types.h>
7 #include <sys/socket.h>
8 
9 #include <netinet/in.h>
10 
11 #include <stdio.h>
12 #include <netdb.h>
13 
14 #define	OUTFILE		"hosts.txt"	/* default output file */
15 #define	QUERY		"ALL\r\n"	/* query to hostname server */
16 
17 #define	equaln(s1, s2, n)	(!strncmp(s1, s2, n))
18 
19 struct	sockaddr_in sin;
20 char	buf[BUFSIZ];
21 char	*outfile = OUTFILE;
22 
23 main(argc, argv)
24 	int argc;
25 	char *argv[];
26 {
27 	int s;
28 	register len;
29 	register FILE *sfi, *sfo, *hf;
30 	register char *p;
31 	char *host;
32 	register struct hostent *hp;
33 	struct servent *sp;
34 
35 	argv++, argc--;
36 	if (argc < 1 || argc > 2) {
37 		fprintf(stderr, "usage: gettable host [ file ]\n");
38 		exit(1);
39 	}
40 	sp = getservbyname("hostnames", "tcp");
41 	if (sp == NULL) {
42 		fprintf(stderr, "gettable: hostnames/tcp: unknown service\n");
43 		exit(3);
44 	}
45 	host = *argv;
46 	argv++, argc--;
47 	hp = gethostbyname(host);
48 	if (hp == NULL) {
49 		fprintf(stderr, "gettable: %s: host unknown\n", host);
50 		exit(2);
51 	}
52 	host = hp->h_name;
53 	if (argc > 0)
54 		outfile = *argv;
55 	sin.sin_family = hp->h_addrtype;
56 	s = socket(hp->h_addrtype, SOCK_STREAM, 0, 0);
57 	if (s < 0) {
58 		perror("gettable: socket");
59 		exit(4);
60 	}
61 	if (bind(s, &sin, sizeof (sin), 0) < 0) {
62 		perror("gettable: bind");
63 		exit(5);
64 	}
65 	bcopy(hp->h_addr, &sin.sin_addr, hp->h_length);
66 	sin.sin_port = sp->s_port;
67 	if (connect(s, &sin, sizeof (sin), 0) < 0) {
68 		perror("gettable: connect");
69 		exit(6);
70 	}
71 	fprintf(stderr, "Connection to %s opened.\n", host);
72 	sfi = fdopen(s, "r");
73 	sfo = fdopen(s, "w");
74 	if (sfi == NULL || sfo == NULL) {
75 		perror("gettable: fdopen");
76 		close(s);
77 		exit(1);
78 	}
79 	hf = fopen(outfile, "w");
80 	if (hf == NULL) {
81 		fprintf(stderr, "gettable: "); perror(outfile);
82 		close(s);
83 		exit(1);
84 	}
85 	fprintf(sfo, QUERY);
86 	fflush(sfo);
87 	while (fgets(buf, sizeof(buf), sfi) != NULL) {
88 		len = strlen(buf);
89 		buf[len-2] = '\0';
90 		if (equaln(buf, "BEGIN", 5) || equaln(buf, "END", 3)) {
91 			continue;
92 		}
93 		if (equaln(buf, "ERR", 3)) {
94 			fprintf(stderr, "gettable: hostnames error: %s", buf);
95 			continue;
96 		}
97 		fprintf(hf, "%s\n", buf);
98 	}
99 	fclose(hf);
100 	fprintf(stderr, "Host table received.\n");
101 	close(s);
102 	fprintf(stderr, "Connection to %s closed\n", host);
103 }
104