![[BACK]](/cvsweb/icons/back.gif){kind=icon}
Return to gethostnamadr.c CVS log ![[TXT]](/cvsweb/icons/text.gif){kind=icon}
![[DIR]](/cvsweb/icons/dir.gif){kind=icon}
Up to [CSRG BSD Unix] / 43BSDTahoe / lib / libc / net / hosttable|
Return to gethostnamadr.c CVS log | Up to [CSRG BSD Unix] / 43BSDTahoe / lib / libc / net / hosttable |
1.1 root 1: /*
2: * Copyright (c) 1983 Regents of the University of California.
3: * All rights reserved.
4: *
5: * Redistribution and use in source and binary forms are permitted
6: * provided that the above copyright notice and this paragraph are
7: * duplicated in all such forms and that any documentation,
8: * advertising materials, and other materials related to such
9: * distribution and use acknowledge that the software was developed
10: * by the University of California, Berkeley. The name of the
11: * University may not be used to endorse or promote products derived
12: * from this software without specific prior written permission.
13: * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
14: * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
15: * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.
16: */
17:
18: #if defined(LIBC_SCCS) && !defined(lint)
19: static char sccsid[] = "@(#)gethostnamadr.c 5.7 (Berkeley) 6/27/88";
20: #endif /* LIBC_SCCS and not lint */
21:
22: #include <stdio.h>
23: #include <netdb.h>
24: #include <sys/file.h>
25: #include <ndbm.h>
26: #include <ctype.h>
27:
28: #define MAXALIASES 35
29:
30: static struct hostent host;
31: static char *host_aliases[MAXALIASES];
32: static char hostbuf[BUFSIZ+1];
33: static char *host_addrs[2];
34:
35: int h_errno;
36:
37: /*
38: * The following is shared with gethostent.c
39: */
40: extern char *_host_file;
41: DBM *_host_db = (DBM *)NULL;
42: int _host_stayopen; /* set by sethostent(), cleared by endhostent() */
43:
44: static struct hostent *
45: fetchhost(key)
46: datum key;
47: {
48: register char *cp, *tp, **ap;
49: int naliases;
50:
51: if (key.dptr == 0)
52: return ((struct hostent *)NULL);
53: key = dbm_fetch(_host_db, key);
54: if (key.dptr == 0)
55: return ((struct hostent *)NULL);
56: cp = key.dptr;
57: tp = hostbuf;
58: host.h_name = tp;
59: while (*tp++ = *cp++)
60: ;
61: bcopy(cp, (char *)&naliases, sizeof(int)); cp += sizeof (int);
62: for (ap = host_aliases; naliases > 0; naliases--) {
63: *ap++ = tp;
64: while (*tp++ = *cp++)
65: ;
66: }
67: *ap = (char *)NULL;
68: host.h_aliases = host_aliases;
69: bcopy(cp, (char *)&host.h_addrtype, sizeof (int));
70: cp += sizeof (int);
71: bcopy(cp, (char *)&host.h_length, sizeof (int));
72: cp += sizeof (int);
73: host.h_addr_list = host_addrs;
74: host.h_addr = tp;
75: bcopy(cp, tp, host.h_length);
76: return (&host);
77: }
78:
79: struct hostent *
80: gethostbyname(nam)
81: register char *nam;
82: {
83: register struct hostent *hp;
84: register char **cp;
85: datum key;
86: char lowname[128];
87: register char *lp = lowname;
88:
89: while (*nam)
90: if (isupper(*nam))
91: *lp++ = tolower(*nam++);
92: else
93: *lp++ = *nam++;
94: *lp = '\0';
95:
96: if ((_host_db == (DBM *)NULL)
97: && ((_host_db = dbm_open(_host_file, O_RDONLY)) == (DBM *)NULL)) {
98: sethostent(_host_stayopen);
99: while (hp = gethostent()) {
100: if (strcmp(hp->h_name, lowname) == 0)
101: break;
102: for (cp = hp->h_aliases; cp != 0 && *cp != 0; cp++)
103: if (strcmp(*cp, lowname) == 0)
104: goto found;
105: }
106: found:
107: if (!_host_stayopen)
108: endhostent();
109: return (hp);
110: }
111: key.dptr = lowname;
112: key.dsize = strlen(lowname);
113: hp = fetchhost(key);
114: if (!_host_stayopen) {
115: dbm_close(_host_db);
116: _host_db = (DBM *)NULL;
117: }
118: if ( hp == NULL)
119: h_errno = HOST_NOT_FOUND;
120: return (hp);
121: }
122:
123: struct hostent *
124: gethostbyaddr(addr, length, type)
125: char *addr;
126: register int length;
127: register int type;
128: {
129: register struct hostent *hp;
130: datum key;
131:
132: if ((_host_db == (DBM *)NULL)
133: && ((_host_db = dbm_open(_host_file, O_RDONLY)) == (DBM *)NULL)) {
134: sethostent(_host_stayopen);
135: while (hp = gethostent()) {
136: if (hp->h_addrtype == type && hp->h_length == length
137: && bcmp(hp->h_addr, addr, length) == 0)
138: break;
139: }
140: if (!_host_stayopen)
141: endhostent();
142: if ( hp == NULL)
143: h_errno = HOST_NOT_FOUND;
144: return (hp);
145: }
146: key.dptr = addr;
147: key.dsize = length;
148: hp = fetchhost(key);
149: if (!_host_stayopen) {
150: dbm_close(_host_db);
151: _host_db = (DBM *)NULL;
152: }
153: if ( hp == NULL)
154: h_errno = HOST_NOT_FOUND;
155: return (hp);
156: }
This archive runs on limited infrastructure. Preserving old code on modern bandwidth. Automated agents are requested to crawl responsibly.