1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22/*
23 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27/*	Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T	*/
28/*	  All Rights Reserved  	*/
29
30#pragma ident	"%Z%%M%	%I%	%E% SMI"
31
32#include "libmail.h"
33#include <sys/types.h>
34#include <ctype.h>
35#ifdef SVR4
36#include <sys/utsname.h>
37#include <sys/systeminfo.h>
38#endif
39
40#define	NMLN 512
41#ifdef SVR4
42#if SYS_NMLN > NMLN
43#undef NMLN
44#define	NMLN SYS_NMLN
45#endif
46#endif
47
48static char *look4domain(char *, char *, int);
49static char *readdomain(char *, int);
50
51/*
52 *  NAME
53 *	maildomain() - retrieve the domain name
54 *
55 *  SYNOPSIS
56 *	char *maildomain()
57 *
58 *  DESCRIPTION
59 *	Retrieve the domain name from xgetenv("DOMAIN").
60 *	If that is not set, look in /etc/resolv.conf, /etc/inet/named.boot
61 *	and /etc/named.boot for "^domain[ ]+<domain>".
62 *	If that is not set, use sysinfo(SI_SRPC_DOMAIN) from
63 *	-lnsl. Otherwise, return an empty string.
64 */
65
66/* read a file for the domain */
67static char *look4domain(char *file, char *buf, int size)
68{
69	char *ret = 0;
70	FILE *fp = fopen(file, "r");
71
72	if (!fp)
73		return (0);
74
75	while (fgets(buf, size, fp))
76		if (strncmp(buf, "domain", 6) == 0)
77	if (isspace(buf[6])) {
78		char *x = skipspace(buf + 6);
79		if (isgraph(*x)) {
80			trimnl(x);
81			strmove(buf, x);
82			ret = buf;
83			break;
84		}
85	}
86
87	(void) fclose(fp);
88	return (ret);
89}
90
91/* read the domain from the xenvironment or one of the files */
92static char *readdomain(char *buf, int size)
93{
94	char *ret;
95
96	if ((ret = xgetenv("DOMAIN")) != 0) {
97		(void) strncpy(buf, ret, size);
98		return (buf);
99	}
100
101	if (((ret = look4domain("/etc/resolv.conf", buf, size)) != 0) ||
102	    ((ret = look4domain("/etc/inet/named.boot", buf, size)) != 0) ||
103	    ((ret = look4domain("/etc/named.boot", buf, size)) != 0))
104		return (ret);
105
106#ifdef SVR4
107	if (sysinfo(SI_SRPC_DOMAIN, buf, size) >= 0)
108		return (buf);
109#endif
110
111	return (0);
112}
113
114char *
115maildomain(void)
116{
117	static char *domain = 0;
118	static char dombuf[NMLN+1] = ".";
119
120	/* if we've already been here, return the info */
121	if (domain != 0)
122		return (domain);
123
124	domain = readdomain(dombuf+1, NMLN);
125
126	/* Make certain that the domain begins with a single dot */
127	/* and does not have one at the end. */
128	if (domain) {
129		size_t len;
130		domain = dombuf;
131		while (*domain && *domain == '.')
132			domain++;
133		domain--;
134		len = strlen(domain);
135		while ((len > 0) && (domain[len-1] == '.'))
136			domain[--len] = '\0';
137	}
138	/* no domain information */
139	else
140		domain = "";
141
142	return (domain);
143}
144