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 /*
28 * m_pathcat: mks specific library routine.
29 *
30 * Copyright 1992 by Mortice Kern Systems Inc. All rights reserved.
31 *
32 */
33
34 #ifdef M_RCSID
35 #ifndef lint
36 static char rcsID[] = "$Header: /rd/src/libc/mks/rcs/m_pathca.c 1.11 1995/04/12 14:14:19 miked Exp $";
37 #endif
38 #endif
39
40 #include <mks.h>
41 #include <errno.h>
42 #include <limits.h>
43 #include <stdlib.h>
44 #include <string.h>
45
46 /*f
47 * Concatenate a directory and filename, inserting / if necessary.
48 * Return dynamically allocated pointer to result string.
49 * On error: return NULL and set errno.
50 *
51 * Errors can occur if:
52 * dir == NULL
53 * file == NULL
54 * dir is an invalid pathname
55 * strlen(dir) + strlen(file) +2 > maximum allowable pathlength
56 *
57 * note: if PATH_MAX has to be retrieved by m_pathmax(dir),
58 * we may return error if the dir name has problems,
59 * which the caller had best expect.
60 */
61 char *
m_pathcat(dir,file)62 m_pathcat(dir, file)
63 const char *dir;
64 const char *file;
65 {
66 char *dest;
67 int dir_len;
68 int file_len;
69 int m;
70 int l;
71
72 if ((dir == NULL) || (file == NULL))
73 goto err;
74
75 #ifdef PATH_MAX
76 l = PATH_MAX;
77 #else
78 l = m_pathmax(dir);
79 if (l < 0)
80 return (NULL); /* Errno is set by m_pathmax() */
81 #endif
82
83 dir_len = strlen(dir);
84 /*
85 * add one for seperator eg. '/'
86 */
87 m = dir_len+1;
88
89 file_len = strlen(file);
90 if (file_len > 0) {
91 /*
92 * add one null termination char
93 */
94 m += file_len+1;
95 }
96
97 if (m > l) {
98 err:
99 #ifdef ENAMETOOLONG
100 errno = ENAMETOOLONG;
101 #else
102 /*
103 * we need to return an errno. So pick EINVAL.
104 * This should be common on all systems.
105 */
106 errno = EINVAL;
107 #endif
108 return (NULL);
109 }
110
111 /*
112 * use m_malloc() - this guarantees a valid errno return on error
113 */
114 if ((dest = m_malloc(m)) == NULL) {
115 return (NULL);
116 }
117
118 strcpy(dest, dir);
119 if (file_len > 0) {
120 if (dir_len > 0
121 && !M_FSDELIM(dest[dir_len-1])
122 && !M_DRDELIM(dest[dir_len-1])) {
123 dest[dir_len++] = '/';
124 }
125 strcpy(dest+dir_len, file);
126 }
127 return (dest);
128 }
129