xref: /illumos-gate/usr/src/lib/libc/port/gen/getcwd.c (revision defc4c8acfa01dba1ef3c13ca0cafccfcede51c0)
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 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 /*
30  * getcwd() returns the pathname of the current working directory.
31  * On error, a NULL pointer is returned and errno is set.
32  */
33 
34 #pragma weak _getcwd = getcwd
35 
36 #include "lint.h"
37 #include <sys/syscall.h>
38 #include <sys/types.h>
39 #include <errno.h>
40 #include <stdlib.h>
41 
42 char *
43 getcwd(char *pathname, size_t size)
44 {
45 	int alloc = 0;
46 
47 	if (size == 0) {
48 		errno = EINVAL;
49 		return (NULL);
50 	}
51 
52 	if (pathname == NULL)  {
53 		if ((pathname = malloc(size)) == NULL) {
54 			errno = ENOMEM;
55 			return (NULL);
56 		}
57 		alloc = 1;
58 	}
59 
60 	if (syscall(SYS_getcwd, pathname, size) == 0)
61 		return (pathname);
62 
63 	if (alloc)
64 		free(pathname);
65 
66 	return (NULL);
67 }
68