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
38 static 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 */
63 char *
m_pathcat(dir,file)64 m_pathcat(dir, file)
65 const char *dir;
66 const 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) {
100 err:
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