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, Version 1.0 only
6 * (the "License").  You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22/*
23 * Copyright (c) 1996, by Sun Microsystems, Inc.
24 * All rights reserved.
25 */
26
27#pragma ident	"%Z%%M%	%I%	%E% SMI"
28
29/*
30 * m_pathcat: mks specific library routine.
31 *
32 * Copyright 1992 by Mortice Kern Systems Inc.  All rights reserved.
33 *
34 */
35
36#ifdef M_RCSID
37#ifndef lint
38static char rcsID[] = "$Header: /rd/src/libc/mks/rcs/m_pathca.c 1.11 1995/04/12 14:14:19 miked Exp $";
39#endif
40#endif
41
42#include <mks.h>
43#include <errno.h>
44#include <limits.h>
45#include <stdlib.h>
46#include <string.h>
47
48/*f
49 * Concatenate a directory and filename, inserting / if necessary.
50 * Return dynamically allocated pointer to result string.
51 * On error: return NULL and set errno.
52 *
53 * Errors can occur if:
54 *    dir == NULL
55 *    file == NULL
56 *    dir is an invalid pathname
57 *    strlen(dir) + strlen(file) +2 > maximum allowable pathlength
58 *
59 * note: if PATH_MAX has to be retrieved by m_pathmax(dir),
60 * we may return error if the dir name has problems,
61 * which the caller had best expect.
62 */
63char *
64m_pathcat(dir, file)
65const char *dir;
66const char *file;
67{
68	char *dest;
69	int dir_len;
70	int file_len;
71	int m;
72	int l;
73
74	if ((dir == NULL) || (file == NULL))
75		goto err;
76
77#ifdef	PATH_MAX
78	l = PATH_MAX;
79#else
80	l = m_pathmax(dir);
81	if (l < 0)
82		return (NULL);	/* Errno is set by m_pathmax() */
83#endif
84
85	dir_len = strlen(dir);
86	/*
87	 * add one for seperator eg. '/'
88	 */
89	m = dir_len+1;
90
91	file_len = strlen(file);
92	if (file_len > 0) {
93		/*
94		 * add one null termination char
95		 */
96		m += file_len+1;
97	}
98
99	if (m > l) {
100err:
101#ifdef	ENAMETOOLONG
102		errno = ENAMETOOLONG;
103#else
104		/*
105		 * we need to return an errno. So pick EINVAL.
106		 * This should be common on all systems.
107		 */
108		errno = EINVAL;
109#endif
110		return (NULL);
111	}
112
113	/*
114	 * use m_malloc() - this guarantees a valid errno return on error
115	 */
116	if ((dest = m_malloc(m)) == NULL) {
117		return (NULL);
118	}
119
120	strcpy(dest, dir);
121	if (file_len > 0) {
122		if (dir_len > 0
123		    && !M_FSDELIM(dest[dir_len-1])
124		    && !M_DRDELIM(dest[dir_len-1])) {
125			dest[dir_len++] = '/';
126		}
127		strcpy(dest+dir_len, file);
128	}
129	return (dest);
130}
131