xref: /illumos-gate/usr/src/lib/libc/port/sys/readlink.c (revision 55d6cb5d63bcf69dfa47b8c41c770a2d34f169b0)
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 (c) 2010, Oracle and/or its affiliates. All rights reserved.
24  */
25 
26 #include "lint.h"
27 #include <sys/syscall.h>
28 #include <sys/unistd.h>
29 #include <sys/fcntl.h>
30 
31 ssize_t
32 readlinkat(int fd, const char *path, char *buf, size_t bufsize)
33 {
34 	sysret_t rval;
35 	int error;
36 
37 	error = __systemcall(&rval, SYS_readlinkat, fd, path, buf, bufsize);
38 	if (error)
39 		(void) __set_errno(error);
40 	return ((ssize_t)rval.sys_rval1);
41 }
42 
43 #pragma weak _readlink = readlink
44 ssize_t
45 readlink(const char *path, char *buf, size_t bufsize)
46 {
47 #if defined(_RETAIN_OLD_SYSCALLS)
48 	sysret_t rval;
49 	int error;
50 
51 	error = __systemcall(&rval, SYS_readlink, path, buf, bufsize);
52 	if (error)
53 		(void) __set_errno(error);
54 	return ((ssize_t)rval.sys_rval1);
55 #else
56 	return (readlinkat(AT_FDCWD, path, buf, bufsize));
57 #endif
58 }
59