1/***********************************************************************
2*                                                                      *
3*               This software is part of the ast package               *
4*          Copyright (c) 1985-2011 AT&T Intellectual Property          *
5*                      and is licensed under the                       *
6*                  Common Public License, Version 1.0                  *
7*                    by AT&T Intellectual Property                     *
8*                                                                      *
9*                A copy of the License is available at                 *
10*            http://www.opensource.org/licenses/cpl1.0.txt             *
11*         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
12*                                                                      *
13*              Information and Software Systems Research               *
14*                            AT&T Research                             *
15*                           Florham Park NJ                            *
16*                                                                      *
17*                 Glenn Fowler <gsf@research.att.com>                  *
18*                  David Korn <dgk@research.att.com>                   *
19*                   Phong Vo <kpv@research.att.com>                    *
20*                                                                      *
21***********************************************************************/
22#pragma prototyped
23
24#include <ast.h>
25
26#if _lib_readlink
27
28NoN(readlink)
29
30#else
31
32#include "fakelink.h"
33
34#include <error.h>
35
36#ifndef ENOSYS
37#define ENOSYS	EINVAL
38#endif
39
40int
41readlink(const char* path, char* buf, int siz)
42{
43	int	fd;
44	int	n;
45
46	if (siz > sizeof(FAKELINK_MAGIC))
47	{
48		if ((fd = open(path, O_RDONLY)) < 0)
49			return -1;
50		if (read(fd, buf, sizeof(FAKELINK_MAGIC)) == sizeof(FAKELINK_MAGIC) && !strcmp(buf, FAKELINK_MAGIC) && (n = read(fd, buf, siz)) > 0 && !buf[n - 1])
51		{
52			close(fd);
53			return n;
54		}
55		close(fd);
56	}
57	errno = ENOSYS;
58	return -1;
59}
60
61#endif
62